ORCID Profile
0000-0002-5350-6852
Current Organisations
University of Sydney
,
University of Adelaide
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Publisher: Elsevier BV
Date: 12-2018
DOI: 10.1016/J.SCITOTENV.2018.07.168
Abstract: Niche segregation allows competing species to capture resources in contrasting ways so they can co-exist and maintain ersity, yet global change is simplifying ecosystems and associated niche ersity. Whether climate perturbations alter niche occupancy among co-occurring species and affect species ersity is a key, but unanswered question. Using CO
Publisher: Elsevier BV
Date: 05-1999
Publisher: Wiley
Date: 29-09-2022
DOI: 10.1111/GCB.16410
Abstract: The paradigm that climate change will alter global marine bio ersity is one of the most widely accepted. Yet, its predictions remain difficult to test because laboratory systems are inadequate at incorporating ecological complexity, and common bio ersity metrics have varying sensitivity to detect change. Here, we test for the prevalence of global responses in bio ersity and community‐level change to future climate (acidification and warming) from studies at volcanic CO 2 vents across four major global coastal ecosystems and studies in laboratory mesocosms. We detected globally replicable patterns of species replacements and community reshuffling under ocean acidification in major natural ecosystems, yet species ersity and other common bio ersity metrics were often insensitive to detect such community change, even under significant habitat loss. Where there was a lack of consistent patterns of bio ersity change, these were a function of similar numbers of studies observing negative versus positive species responses to climate stress. Laboratory studies showed weaker sensitivity to detect species replacements and community reshuffling in general. We conclude that common bio ersity metrics can be insensitive in revealing the anticipated effects of climate stress on bio ersity—even under significant biogenic habitat loss—and can mask widespread reshuffling of ecological communities in a future ocean. Although the influence of ocean acidification on community restructuring can be less evident than species loss, such changes can drive the dynamics of ecosystem stability or their functional change. Importantly, species identity matters, representing a substantial influence of future oceans.
Publisher: Wiley
Date: 07-06-2014
DOI: 10.1111/JBI.12359
Publisher: Inter-Research Science Center
Date: 26-03-2009
DOI: 10.3354/AB00146
Publisher: Springer Science and Business Media LLC
Date: 09-07-2018
DOI: 10.1038/S41559-018-0607-2
Abstract: Farming is a technique employed by both humans and animals to enhance crop yields, allowing their populations to increase beyond the natural carrying capacity of the environment. Using volcanic CO
Publisher: Elsevier BV
Date: 02-2015
Publisher: Elsevier BV
Date: 06-1997
Publisher: Public Library of Science (PLoS)
Date: 29-03-2011
Publisher: Springer Netherlands
Date: 2014
Publisher: The Royal Society
Date: 31-01-2019
Abstract: Increasing carbon emissions not only enrich oceans with CO 2 but also make them more acidic. This acidifying process has caused considerable concern because laboratory studies show that ocean acidification impairs calcification (or shell building) and survival of calcifiers by the end of this century. Whether this impairment in shell building also occurs in natural communities remains largely unexplored, but requires re-examination because of the recent counterintuitive finding that populations of calcifiers can be boosted by CO 2 enrichment. Using natural CO 2 vents, we found that ocean acidification resulted in the production of thicker, more crystalline and more mechanically resilient shells of a herbivorous gastropod, which was associated with the consumption of energy-enriched food (i.e. algae). This discovery suggests that boosted energy transfer may not only compensate for the energetic burden of ocean acidification but also enable calcifiers to build energetically costly shells that are robust to acidified conditions. We unlock a possible mechanism underlying the persistence of calcifiers in acidifying oceans.
Publisher: Elsevier BV
Date: 10-2009
Publisher: Springer Science and Business Media LLC
Date: 24-02-2006
DOI: 10.1007/S00442-006-0389-0
Abstract: Assembly rules provide a useful framework for predicting patterns of community assembly under defined environmental conditions. Habitat created by canopy-forming algae (such as kelps) provides a promising system for identifying assembly rules because canopies typically have a large and predictable influence on understorey communities. Across >1,000 km of subtidal South Australian coastline, we identified natural associations between assemblages of understorey algae and (1) monospecific canopies of Ecklonia radiata, (2) canopies comprised of E. radiata mixed with Fucales (Cystophora spp. and Sargassum spp.), and (3) gaps among canopies of algae. We were able to recreate these associations with experimental tests that quantified the assembly of understorey algae among these three habitat types. We propose the assembly rule that understorey communities on subtidal rocky coast in South Australia will be (1) monopolised by encrusting coralline algae beneath monospecific canopies of E. radiata, (2) comprised of encrusting corallines, encrusting non-corallines, and sparse covers of articulated corallines, beneath mixed E. radiata-Fucales canopies, and (3) comprised of extensive covers of articulated corallines and filamentous turfs, as well as sparse covers of foliose algae and juvenile canopy-formers, within gaps. Consistencies between natural patterns and experimental effects demonstrate how algal canopies can act as a filter to limit the subsets of species from the locally available pool that are able to assemble beneath them. Moreover, the subsets of species that assemble to subtidal rocky substrata in South Australia appear to be predictable, given knowledge of the presence and composition of canopies incorporating E. radiata.
Publisher: The Royal Society
Date: 07-07-2021
Abstract: Negative interactions among species are a major force shaping natural communities and are predicted to strengthen as climate change intensifies. Similarly, positive interactions are anticipated to intensify and could buffer the consequences of climate-driven disturbances. We used in situ experiments at volcanic CO 2 vents within a temperate rocky reef to show that ocean acidification can drive community reorganization through indirect and direct positive pathways. A keystone species, the algal-farming damselfish Parma alboscapularis, enhanced primary productivity through its weeding of algae whose productivity was also boosted by elevated CO 2 . The accelerated primary productivity was associated with increased densities of primary consumers (herbivorous invertebrates), which indirectly supported increased secondary consumers densities (predatory fish) (i.e. strengthening of bottom-up fuelling). However, this keystone species also reduced predatory fish densities through behavioural interference, releasing invertebrate prey from predation pressure and enabling a further boost in prey densities (i.e. weakening of top-down control). We uncover a novel mechanism where a keystone herbivore mediates bottom-up and top-down processes simultaneously to boost populations of a coexisting herbivore, resulting in altered food web interactions and predator populations under future ocean acidification.
Publisher: Inter-Research Science Center
Date: 1999
DOI: 10.3354/MEPS187203
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/MF04270
Abstract: This study compares the cost (time and funds) and benefits (precision and accuracy) of methods commonly used to estimate percentage cover of sessile marine organisms. We applied nine methods to morphological groups of benthic algae and broad taxonomic groups of sessile invertebrates including varying the intensity of s ling (25 v. 50 v. 100 point-intercepts), random v. regular arrays, in situ v. laboratory v. photographic s ling v. computer digitising. We detected little to no difference in estimates of percentage cover among methods, indicating that accuracy is unlikely to be an important issue that distinguishes methods. Precision was generally unaffected by the intensity of s ling within quadrats (25 v. 50 v. 100 point-intercepts) or between environments (in situ v. on photographs v. within the laboratory) and appeared to be of secondary concern to decisions about replication. Computer digitising (estimates of surface area of each taxon) provided the least precise estimates and did not justify the additional laboratory time required to process them. Depending on whether field expenses or laboratory expenses are of the greatest concern, the techniques that permit the greatest coverage of area (greatest replication) are likely to produce the most representative (accurate) and reliable (precise) estimates.
Publisher: Wiley
Date: 17-03-2011
Publisher: Inter-Research Science Center
Date: 05-02-2014
DOI: 10.3354/MEPS10557
Publisher: Springer Science and Business Media LLC
Date: 09-07-2005
Publisher: Informa UK Limited
Date: 04-2014
DOI: 10.2216/13-197.1
Publisher: Elsevier BV
Date: 05-2001
DOI: 10.1016/S0022-0981(01)00246-5
Abstract: Foraging by predatory fish is thought to be one of the primary ecological processes affecting the abundances of plants and animals in subtidal habitats. The importance of this process was assessed on the subtidal surfaces of urban structures (pontoons and pilings) that represent major coastal habitats for marine organisms. Fish feed with greater intensity on epibiota attached to pilings than pontoons and it was hypothesised that greater predation on pilings explained why the structure of epibiotic assemblages differs between these habitats. I predicted that the structure of epibiotic assemblages would develop differently between pilings and pontoons in the presence of fish (plates open to predation) but not in the absence of fish (plates inside exclusion cages). Results revealed large differences in abundance between pilings and pontoons that were largely independent of the caged and uncaged plates. Predation may be intense (as it appeared on pilings) but unimportant because it does not explain observed abundances of prey (epibiota between pilings and pontoons).
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/MF06216
Abstract: It is remarkable that although the importance of depth is firmly rooted in the discipline of marine ecology, so little is understood about depth-related patterns of invertebrates in kelp forests, particularly in temperate Australia. We tested for the existence of broad scale patterns in depth-related ersity and abundance of mobile invertebrates in kelp holdfasts (Ecklonia radiata) across several spatial scales along 500 km of coastline. There was a greater abundance and richness of common taxa in holdfasts from shallow relative to deep waters. Strikingly, a disproportionately large percentage (60%) of species was unique to holdfasts from shallow reefs, suggesting that shallow environments create conditions that facilitate a rich bio ersity of invertebrate fauna. We conclude that depth-related variation in kelp forests may not be completely idiosyncratic, and coherent research programs of a broader scale and scope may unify subsets of fragmented knowledge that previously provided little insight into general depth-related patterns of invertebrate assemblages.
Publisher: Proceedings of the National Academy of Sciences
Date: 08-01-2019
Publisher: The Royal Society
Date: 07-09-2012
Abstract: Most studies that forecast the ecological consequences of climate change target a single species and a single life stage. Depending on climatic impacts on other life stages and on interacting species, however, the results from simple experiments may not translate into accurate predictions of future ecological change. Research needs to move beyond simple experimental studies and environmental envelope projections for single species towards identifying where ecosystem change is likely to occur and the drivers for this change. For this to happen, we advocate research directions that (i) identify the critical species within the target ecosystem, and the life stage(s) most susceptible to changing conditions and (ii) the key interactions between these species and components of their broader ecosystem. A combined approach using macroecology, experimentally derived data and modelling that incorporates energy budgets in life cycle models may identify critical abiotic conditions that disproportionately alter important ecological processes under forecasted climates.
Publisher: Springer Science and Business Media LLC
Date: 09-2003
DOI: 10.1007/S00442-003-1312-6
Abstract: Marine macroalgal forests are one of the most widespread and studied habitats on subtidal coasts, but there remain challenges in understanding why many sessile invertebrates are anomalously absent from understorey communities. In a series of experiments on recruitment of invertebrates, I partitioned the habitat-modifying effects of kelp into their positive and negative effects. Experiments revealed that a reduction of light intensity and removal of sediment by canopies acted to facilitate recruitment, but physical abrasion by the canopy acted as a negative force to overpower these positive effects. Understorey assemblages, therefore, represent biased subsets of taxa from a local pool capable of colonization. On balance, negative effects acted to exclude invertebrates from the understorey community. The asymmetric strength of negative effects not only explains the enigma of exclusion but also indicates that, when it exists, understorey coexistence with canopy plants must reflect a more even match between positive and negative effects.
Publisher: American Chemical Society (ACS)
Date: 15-02-2017
Abstract: Calcifying organisms are considered particularly susceptible to the future impacts of ocean acidification (OA), but recent evidence suggests that they may be able to maintain calcification and overall fitness. The underlying mechanism remains unclear but may be attributed to mineralogical plasticity, which modifies the energetic cost of calcification. To test the hypothesis that mineralogical plasticity enables the maintenance of shell growth and functionality under OA conditions, we assessed the biological performance of a gastropod (respiration rate, feeding rate, somatic growth, and shell growth of Austrocochlea constricta) and analyzed its shell mechanical and geochemical properties (shell hardness, elastic modulus, amorphous calcium carbonate, calcite to aragonite ratio, and magnesium to calcium ratio). Despite minor metabolic depression and no increase in feeding rate, shell growth was faster under OA conditions, probably due to increased precipitation of calcite and trade-offs against inner shell density. In addition, the resulting shell was functionally suitable for increasingly "corrosive" oceans, i.e., harder and less soluble shells. We conclude that mineralogical plasticity may act as a compensatory mechanism to maintain overall performance of calcifying organisms under OA conditions and could be a cornerstone of calcifying organisms to acclimate to and maintain their ecological functions in acidifying oceans.
Publisher: Wiley
Date: 11-01-2015
DOI: 10.1111/ELE.12405
Abstract: Disturbance often results in small changes in community structure, but the probability of transitioning to contrasting states increases when multiple disturbances combine. Nevertheless, we have limited insights into the mechanisms that stabilise communities, particularly how perturbations can be absorbed without restructuring (i.e. resistance). Here, we expand the concept of compensatory dynamics to include countervailing mechanisms that absorb disturbances through trophic interactions. By definition, 'compensation' occurs if a specific disturbance stimulates a proportional countervailing response that eliminates its otherwise unchecked effect. We show that the compounding effects of disturbances from local to global scales (i.e. local canopy-loss, eutrophication, ocean acidification) increasingly promote the expansion of weedy species, but that this response is countered by a proportional increase in grazing. Finally, we explore the relatively unrecognised role of compensatory effects, which are likely to maintain the resistance of communities to disturbance more deeply than current thinking allows.
Publisher: Elsevier BV
Date: 10-2004
Publisher: Wiley
Date: 2015
DOI: 10.1890/14-0802.1
Abstract: Ocean acidification, chemical changes to the carbonate system of seawater, is emerging as a key environmental challenge accompanying global warming and other human-induced perturbations. Considerable research seeks to define the scope and character of potential outcomes from this phenomenon, but a crucial impediment persists. Ecological theory, despite its power and utility, has been only peripherally applied to the problem. Here we sketch in broad strokes several areas where fundamental principles of ecology have the capacity to generate insight into ocean acidification's consequences. We focus on conceptual models that, when considered in the context of acidification, yield explicit predictions regarding a spectrum of population- and community-level effects, from narrowing of species ranges and shifts in patterns of demographic connectivity, to modified consumer-resource relationships, to ascendance of weedy taxa and loss of species ersity. Although our coverage represents only a small fraction of the breadth of possible insights achievable from the application of theory, our hope is that this initial foray will spur expanded efforts to blend experiments with theoretical approaches. The result promises to be a deeper and more nuanced understanding of ocean acidification'and the ecological changes it portends.
Publisher: Wiley
Date: 02-2001
Publisher: Elsevier BV
Date: 07-2015
Publisher: Wiley
Date: 09-08-2020
Abstract: A multi‐species approach to habitat restoration may boost the key processes (e.g. recruitment) that enable foundation species to overcome barriers to recovery. Natural systems tend to be formed by co‐occurring foundation species whose synergy drives ecological productivity and resilience beyond that of single foundation species. Yet, restoration remains primarily a single‐species focus enterprise where positive interactions are seldom incorporated into planning. A multi‐species approach that prioritizes species combinations that create emergent properties for their persistence may accelerate habitat recovery and the success of restoration programmes. On the largest oyster reef restoration project in the Southern Hemisphere, we experimentally established canopy‐forming kelp to test whether they could accelerate the natural recruitment of oysters to substrata monopolized by turf‐forming algae. To understand whether facilitation of oysters was a function of the kelp themselves (biological facilitation) or the physical environment they create (physical facilitation), we compared recruitment to the understorey of living kelp and synthetic kelp mimics. Despite observing high density oyster recruitment to the turf‐free underside of reef boulders (8,300 oysters/m 2 ), turf algae appeared to inhibit oyster recruitment to the exposed surfaces of the reef, limiting their capacity to grow and form complex, three‐dimensional habitat. Transplanted kelp, whether living or synthetic kelp mimics, effectively reduced the biomass of turf and enhanced oyster recruitment, creating turf‐free substrata on the upper reef surfaces with up to 26 times the oyster recruitment than turf‐covered substrata. Synthesis and applications . Our results provide proof‐of‐concept that incorporating the transplant of canopy‐forming kelp to reefs constructed to restore oysters is not only achievable, but may be imperative to successfully restore oyster reefs in turf‐dominated systems. Kelp transplants suppressed the turf algae that otherwise excluded oysters from the reef surface, effectively shifting the competitive advantage toward oyster recovery by maintaining bare substrata for oyster recruitment. By demonstrating that a multi‐species approach to restoration accelerates the recovery of a restored habitat, we emphasize the value of incorporating the multi‐species concept into restoration planning.
Publisher: Informa UK Limited
Date: 04-07-2021
Publisher: Inter-Research Science Center
Date: 21-06-2017
DOI: 10.3354/MEPS12165
Publisher: Springer Science and Business Media LLC
Date: 08-02-2021
Publisher: Elsevier BV
Date: 02-2015
Publisher: Elsevier BV
Date: 11-2011
DOI: 10.1016/J.CUB.2011.09.028
Abstract: In recent decades, global climate change [1] has caused profound biological changes across the planet [2-6]. However, there is a great disparity in the strength of evidence among different ecosystems and between hemispheres: changes on land have been well documented through long-term studies, but similar direct evidence for impacts of warming is virtually absent from the oceans [3, 7], where only a few studies on in idual species of intertidal invertebrates, plankton, and commercially important fish in the North Atlantic and North Pacific exist. This disparity of evidence is precarious for biological conservation because of the critical role of the marine realm in regulating the Earth's environmental and ecological functions, and the associated socioeconomic well-being of humans [8]. We interrogated a database of >20,000 herbarium records of macroalgae collected in Australia since the 1940s and documented changes in communities and geographical distribution limits in both the Indian and Pacific Oceans, consistent with rapid warming over the past five decades [9, 10]. We show that continued warming might drive potentially hundreds of species toward and beyond the edge of the Australian continent where sustained retreat is impossible. The potential for global extinctions is profound considering the many endemic seaweeds and seaweed-dependent marine organisms in temperate Australia.
Publisher: Springer Science and Business Media LLC
Date: 18-10-2006
Publisher: Wiley
Date: 03-09-2013
DOI: 10.1111/GCB.12289
Abstract: Evidence is accumulating that species' responses to climate changes are best predicted by modelling the interaction of physiological limits, biotic processes and the effects of dispersal-limitation. Using commercially harvested blacklip (Haliotis rubra) and greenlip abalone (Haliotis laevigata) as case studies, we determine the relative importance of accounting for interactions among physiology, metapopulation dynamics and exploitation in predictions of range (geographical occupancy) and abundance (spatially explicit density) under various climate change scenarios. Traditional correlative ecological niche models (ENM) predict that climate change will benefit the commercial exploitation of abalone by promoting increased abundances without any reduction in range size. However, models that account simultaneously for demographic processes and physiological responses to climate-related factors result in future (and present) estimates of area of occupancy (AOO) and abundance that differ from those generated by ENMs alone. Range expansion and population growth are unlikely for blacklip abalone because of important interactions between climate-dependent mortality and metapopulation processes in contrast, greenlip abalone should increase in abundance despite a contraction in AOO. The strongly non-linear relationship between abalone population size and AOO has important ramifications for the use of ENM predictions that rely on metrics describing change in habitat area as proxies for extinction risk. These results show that predicting species' responses to climate change often require physiological information to understand climatic range determinants, and a metapopulation model that can make full use of this data to more realistically account for processes such as local extirpation, demographic rescue, source-sink dynamics and dispersal-limitation.
Publisher: Proceedings of the National Academy of Sciences
Date: 12-10-2015
Abstract: People are not only concerned about climate change and its effects on plant and animal ersity but also about how humans are fundamentally changing the globe’s largest ecosystem that sustains economic revenue and food for many countries. We show that many species communities and ocean habitats will change from their current states. Ocean acidification and warming increase the potential for an overall simplification of ecosystem structure and function with reduced energy flow among trophic levels and little scope for species to acclimate. The future simplification of our oceans has profound consequences for our current way of life, particularly for coastal populations and those that rely on oceans for food and trade.
Publisher: Wiley
Date: 03-07-2023
DOI: 10.1111/REC.13975
Abstract: Techniques that enhance the recruitment of foundation species to restoration sites can inform the ecological development of the restored habitat. However, techniques are often considered in isolation, potentially overlooking synergies from combining them. Native oyster reefs have been lost worldwide, resulting in restoration efforts in systems that are often recruitment limited, or where recruiting oysters must spatially compete with opportunistic species. Here, we present a field‐based study that combines ecological knowledge on positive species interactions with novel acoustic technology, both of which are demonstrated to boost oyster recruitment in isolation, to test whether their interaction synergistically enhances the early larval recruitment that drives oyster reef development. At three sites across a 20 ha oyster reef restoration in southern Australia, we used self‐made speakers to broadcast healthy reef soundscapes that attract oysters and combine this with artificial kelp that facilitates oyster recruitment by suppressing competitive species (turfing algae). The combination of acoustic enrichment and artificial kelp increased oyster recruitment to the topside of substrate (326.98% increase), whereas only acoustic enrichment increased recruitment to the underside of substrate (126.95% increase). Our findings suggest that the combination of multiple techniques and their interactive effects might boost the early stages of reef development, providing proof‐of‐concept that these approaches can help oysters to build and bind reefs (i.e. recruit to the topside and underside, respectively). By combining ecology with technology during the first stages of a developing reef restoration, we show the potential value of these novel approaches to kick‐start the recovery of lost oyster reefs.
Publisher: Springer Science and Business Media LLC
Date: 23-01-2013
Publisher: Inter-Research Science Center
Date: 08-11-2007
DOI: 10.3354/MEPS07097
Publisher: Wiley
Date: 06-08-2017
DOI: 10.1111/GCB.13414
Abstract: The combination of ocean warming and acidification brings an uncertain future to kelp forests that occupy the warmest parts of their range. These forests are not only subject to the direct negative effects of ocean climate change, but also to a combination of unknown indirect effects associated with changing ecological landscapes. Here, we used mesocosm experiments to test the direct effects of ocean warming and acidification on kelp biomass and photosynthetic health, as well as climate-driven disparities in indirect effects involving key consumers (urchins and rock lobsters) and competitors (algal turf). Elevated water temperature directly reduced kelp biomass, while their turf-forming competitors expanded in response to ocean acidification and declining kelp canopy. Elevated temperatures also increased growth of urchins and, concurrently, the rate at which they thinned kelp canopy. Rock lobsters, which are renowned for keeping urchin populations in check, indirectly intensified negative pressures on kelp by reducing their consumption of urchins in response to elevated temperature. Overall, these results suggest that kelp forests situated towards the low-latitude margins of their distribution will need to adapt to ocean warming in order to persist in the future. What is less certain is how such adaptation in kelps can occur in the face of intensifying consumptive (via ocean warming) and competitive (via ocean acidification) pressures that affect key ecological interactions associated with their persistence. If such indirect effects counter adaptation to changing climate, they may erode the stability of kelp forests and increase the probability of regime shifts from complex habitat-forming species to more simple habitats dominated by algal turfs.
Publisher: Elsevier BV
Date: 04-1999
Publisher: The Royal Society
Date: 05-10-2013
Abstract: Predictions concerning the consequences of the oceanic uptake of increasing atmospheric carbon dioxide (CO 2 ) have been primarily occupied with the effects of ocean acidification on calcifying organisms, particularly those critical to the formation of habitats (e.g. coral reefs) or their maintenance (e.g. grazing echinoderms). This focus overlooks direct and indirect effects of CO 2 on non-calcareous taxa that play critical roles in ecosystem shifts (e.g. competitors). We present the model that future atmospheric [CO 2 ] may act as a resource for mat-forming algae, a erse and widespread group known to reduce the resilience of kelp forests and coral reefs. We test this hypothesis by combining laboratory and field CO 2 experiments and data from ‘natural’ volcanic CO 2 vents. We show that mats have enhanced productivity in experiments and more expansive covers in situ under projected near-future CO 2 conditions both in temperate and tropical conditions. The benefits of CO 2 are likely to vary among species of producers, potentially leading to shifts in species dominance in a high CO 2 world. We explore how ocean acidification combines with other environmental changes across a number of scales, and raise awareness of CO 2 as a resource whose change in availability could have wide-ranging community consequences beyond its direct effects.
Publisher: Elsevier BV
Date: 10-2018
DOI: 10.1016/J.SCITOTENV.2018.05.161
Abstract: The CO
Publisher: No publisher found
Date: 2000
Publisher: Springer Science and Business Media LLC
Date: 25-03-2004
Publisher: Wiley
Date: 23-06-2005
Publisher: Public Library of Science (PLoS)
Date: 16-03-2012
Publisher: American Society of Civil Engineers (ASCE)
Date: 12-2017
Publisher: Springer Science and Business Media LLC
Date: 15-12-2017
DOI: 10.1038/S41598-017-16341-1
Abstract: Extreme climatic events, such as heatwaves, are predicted to be more prevalent in future due to global climate change. The devastating impacts of heatwaves on the survival of marine organisms may be further intensified by ocean acidification. Here, we tested the hypothesis that prolonged exposure to heatwave temperatures (24 °C, +3 °C summer seawater temperature) would diminish energy budget, body condition and ultimately survival of a subtidal gastropod ( Thalotia conica ) by pushing close to its critical thermal maximum (CT max ). We also tested whether ocean acidification ( p CO 2 : 1000 ppm) affects energy budget, CT max and hence survival of this gastropod. Following the 8-week experimental period, mortality was markedly higher at 24 °C irrespective of p CO 2 level, probably attributed to energy deficit (negative scope for growth) and concomitant depletion of energy reserves (reduced organ weight to flesh weight ratio). CT max of T . conica appeared at 27 °C and was unaffected by ocean acidification. Our findings imply that prolonged exposure to heatwaves can compromise the survival of marine organisms below CT max via disruption in energy homeostasis, which possibly explains their mass mortality in the past heatwave events. Therefore, heatwaves would have more profound effects than ocean acidification on future marine ecosystems.
Publisher: Elsevier BV
Date: 02-2012
Publisher: The Royal Society
Date: 06-01-2010
Abstract: Predictions about the ecological consequences of oceanic uptake of CO 2 have been preoccupied with the effects of ocean acidification on calcifying organisms, particularly those critical to the formation of habitats (e.g. coral reefs) or their maintenance (e.g. grazing echinoderms). This focus overlooks the direct effects of CO 2 on non-calcareous taxa, particularly those that play critical roles in ecosystem shifts. We used two experiments to investigate whether increased CO 2 could exacerbate kelp loss by facilitating non-calcareous algae that, we hypothesized, (i) inhibit the recovery of kelp forests on an urbanized coast, and (ii) form more extensive covers and greater biomass under moderate future CO 2 and associated temperature increases. Our experimental removal of turfs from a phase-shifted system (i.e. kelp- to turf-dominated) revealed that the number of kelp recruits increased, thereby indicating that turfs can inhibit kelp recruitment. Future CO 2 and temperature interacted synergistically to have a positive effect on the abundance of algal turfs, whereby they had twice the biomass and occupied over four times more available space than under current conditions. We suggest that the current preoccupation with the negative effects of ocean acidification on marine calcifiers overlooks potentially profound effects of increasing CO 2 and temperature on non-calcifying organisms.
Publisher: Elsevier BV
Date: 08-2019
Publisher: Elsevier BV
Date: 10-2017
DOI: 10.1016/J.CUB.2017.08.057
Abstract: Rising levels of carbon dioxide (CO
Publisher: Springer Science and Business Media LLC
Date: 19-12-2006
Publisher: Wiley
Date: 07-08-2022
DOI: 10.1111/COBI.13958
Abstract: Achieving a sustainable socioecological future now requires large‐scale environmental repair across legislative borders. Yet, enabling large‐scale conservation is complicated by policy‐making processes that are disconnected from socioeconomic interests, multiple sources of knowledge, and differing applications of policy. We considered how a multidisciplinary approach to marine habitat restoration generated the scientific evidence base, community support, and funding needed to begin the restoration of a forgotten, functionally extinct shellfish reef ecosystem. The key actors came together as a multidisciplinary community of researchers, conservation practitioners, recreational fisher communities, and government bodies that collaborated across sectors to rediscover Australia's lost shellfish reefs and communicate the value of its restoration. Actions undertaken to build a case for large‐scale marine restoration included synthesizing current knowledge on Australian shellfish reefs and their historical decline, using this history to tell a compelling story to spark public and political interest, integrating restoration into government policy, and rallying local support through community engagement. Clearly articulating the social, economic, and environmental business case for restoration led to state and national funding for reef restoration to meet erse sustainability goals (e.g., enhanced bio ersity and fisheries productivity) and socioeconomic goals (e.g., job creation and recreational opportunities). A key lesson learned was the importance of aligning project goals with public and industry interests so that projects could address multiple political obligations. This process culminated in Australia's largest marine restoration initiative and shows that solutions for large‐scale ecosystem repair can rapidly occur when socially valued science acts on political opportunities.
Publisher: Wiley
Date: 04-08-2009
Publisher: Wiley
Date: 21-01-2019
DOI: 10.1111/GCB.14536
Abstract: The pervasive enrichment of CO 2 in our oceans is a well‐documented stressor to marine life. Yet, there is little understanding about how CO 2 affects species indirectly in naturally complex communities. Using natural CO 2 vents, we investigated the indirect effects of CO 2 enrichment through a marine food chain. We show how CO 2 boosted the biomass of three trophic levels: from the primary producers (algae), through to their grazers (gastropods), and finally through to their predators (fish). We also found that consumption by both grazers and predators intensified under CO 2 enrichment, but, ultimately, this top‐down control failed to compensate for the boosted biomass of both primary producers and herbivores (bottom‐up control). Our study suggests that indirect effects can buffer the ubiquitous and direct, negative effects of CO 2 enrichment by allowing the upward propagation of resources through the food chain. Maintaining the natural complexity of food webs in our ocean communities could, therefore, help minimize the future impacts of CO 2 enrichment.
Publisher: The Royal Society
Date: 2016
Abstract: The dispersal of larvae and their settlement to suitable habitat is fundamental to the replenishment of marine populations and the communities in which they live. Sound plays an important role in this process because for larvae of various species, it acts as an orientational cue towards suitable settlement habitat. Because marine sounds are largely of biological origin, they not only carry information about the location of potential habitat, but also information about the quality of habitat. While ocean acidification is known to affect a wide range of marine organisms and processes, its effect on marine soundscapes and its reception by navigating oceanic larvae remains unknown. Here, we show that ocean acidification causes a switch in role of present-day soundscapes from attractor to repellent in the auditory preferences in a temperate larval fish. Using natural CO 2 vents as analogues of future ocean conditions, we further reveal that ocean acidification can impact marine soundscapes by profoundly diminishing their biological sound production. An altered soundscape poorer in biological cues indirectly penalizes oceanic larvae at settlement stage because both control and CO 2 -treated fish larvae showed lack of any response to such future soundscapes. These indirect and direct effects of ocean acidification put at risk the complex processes of larval dispersal and settlement.
Publisher: Wiley
Date: 09-08-2020
Publisher: Inter-Research Science Center
Date: 22-05-2008
DOI: 10.3354/MEPS07526
Publisher: Inter-Research Science Center
Date: 2002
DOI: 10.3354/MEPS245083
Publisher: Springer Science and Business Media LLC
Date: 11-05-2005
Publisher: Oxford University Press (OUP)
Date: 11-2001
Publisher: Springer Science and Business Media LLC
Date: 22-06-2017
DOI: 10.1038/S41598-017-03802-W
Abstract: Increasing oceanic uptake of CO 2 is predicted to drive ecological change as both a resource (i.e. CO 2 enrichment on primary producers) and stressor (i.e. lower pH on consumers). We use the natural ecological complexity of a CO 2 vent (i.e. a seagrass system) to assess the potential validity of conceptual models developed from laboratory and mesocosm research. Our observations suggest that the stressor-effect of CO 2 enrichment combined with its resource-effect drives simplified food web structure of lower trophic ersity and shorter length. The transfer of CO 2 enrichment from plants to herbivores through consumption (apparent resource-effect) was not compensated by predation, because carnivores failed to contain herbivore outbreaks. Instead, these higher-order consumers collapsed (apparent stressor-effect on carnivores) suggesting limited trophic propagation to predator populations. The dominance of primary producers and their lower-order consumers along with the loss of carnivores reflects the duality of intensifying ocean acidification acting both as resource-effect (i.e. bottom-up control) and stressor-effect (i.e. top-down control) to simplify community and trophic structure and function. This shifting balance between the propagation of resource enrichment and its consumption across trophic levels provides new insights into how the trophic dynamics might stabilize against or propagate future environmental change.
Publisher: The Royal Society
Date: 2016
Abstract: The antiquity of human impact on ecosystems is increasingly understood, though the arrival of settlers to new lands remains a defining period. Colonization of the ‘neo-Europes’, a reference from the discipline of history, precipitated changes in aquatic ecosystems through modification of waterways and introductions of non-native species. We considered historical fisheries and fish market records from South Australia (1900–1946) against contemporary production statistics (1987–2011). Native inland species historically contributed large quantities to the market but have deteriorated such that fishing is now limited, and conservation regulations exist. This pattern mirrors the demand-driven transition from freshwater to marine fisheries in Europe hence, we propose that this pattern was predicated on societal expectations and that European settlement and introduction of non-native fishes led to systematic overexploitation and degradation of native inland fisheries species in Australia, representing a further consequence of neo-European colonization to ecology. Accurate interpretation of ecological change can ensure more appropriate management intervention. Concepts, such as neo-Europe, from alternative disciplines can inform the recognition and evaluation of patterns at regional and global scales.
Publisher: Springer Science and Business Media LLC
Date: 12-2020
DOI: 10.1007/S00442-015-3438-8
Abstract: Ocean warming is anticipated to strengthen the persistence of turf-forming habitat, yet the concomitant elevation of grazer metabolic rates may accelerate per capita rates of consumption to counter turf predominance. Whilst this possibility of strong top-down control is supported by the metabolic theory of ecology (MTE), it assumes that consumer metabolism and consumption keep pace with increasing production. This assumption was tested by quantifying the metabolic rates of turfs and herbivorous gastropods under a series of elevated temperatures in which the ensuing production and consumption were observed. We discovered that as temperature increases towards near-future levels (year 2100), consumption rates of gastropods peak earlier than the rate of growth of producers. Hence, turfs have greater capacity to persist under near-future temperatures than the capacity for herbivores to counter their growth. These results suggest that whilst MTE predicts stronger top-down control, understanding whether consumer-producer responses are synchronous is key to assessing the future strength of top-down control.
Publisher: Elsevier BV
Date: 10-2015
Publisher: Public Library of Science (PLoS)
Date: 08-11-2013
Publisher: The Royal Society
Date: 05-10-2013
Abstract: Climate change may cause ecosystems to become trophically restructured as a result of primary producers and consumers responding differently to increasing CO 2 and temperature. This study used an integrative approach using a controlled microcosm experiment to investigate the combined effects of CO 2 and temperature on key components of the intertidal system in the UK, biofilms and their consumers ( Littorina littorea ). In addition, to identify whether pre-exposure to experimental conditions can alter experimental outcomes we explicitly tested for differential effects on L. littorea pre-exposed to experimental conditions for two weeks and five months. In contrast to predictions based on metabolic theory, the combination of elevated temperature and CO 2 over a five-week period caused a decrease in the amount of primary productivity consumed by grazers, while the abundance of biofilms increased. However, long-term pre-exposure to experimental conditions (five months) altered this effect, with grazing rates in these animals being greater than in animals exposed only for two weeks. We suggest that the structure of future ecosystems may not be predictable using short-term laboratory experiments alone owing to potentially confounding effects of exposure time and effects of being held in an artificial environment over prolonged time periods. A combination of laboratory (physiology responses) and large, long-term experiments (ecosystem responses) may therefore be necessary to adequately predict the complex and interactive effects of climate change as organisms may acclimate to conditions over the longer term.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 13-08-2020
Abstract: As human activities intensify, the structures of ecosystems and their food webs often reorganize. Through the study of mesocosms harboring a erse benthic coastal community, we reveal that food web architecture can be inflexible under ocean warming and acidification and unable to compensate for the decline or proliferation of taxa. Key stabilizing processes, including functional redundancy, trophic compensation, and species substitution, were largely absent under future climate conditions. A trophic pyramid emerged in which biomass expanded at the base and top but contracted in the center. This structure may characterize a transitionary state before collapse into shortened, bottom-heavy food webs that characterize ecosystems subject to persistent abiotic stress. We show that where food web architecture lacks adjustability, the adaptive capacity of ecosystems to global change is weak and ecosystem degradation likely.
Publisher: Inter-Research Science Center
Date: 31-10-2013
DOI: 10.3354/MEPS10491
Publisher: Oxford University Press (OUP)
Date: 02-11-2016
Abstract: Marine historical research has made progress in bridging the gap between science and policy, but ex les in which it has been effectively applied remain few. In particular, its application to aquaculture remains unexplored. Using actual ex les of natural resource management in the state of South Australia, we illustrate how historical data of varying resolution can be incorporated into aquaculture planning. Historical fisheries records were reviewed to identify data on the now extinct native oyster Ostrea angasi fishery throughout the 1800 and early-1900s. Records of catch, number of boats fishing, and catch per unit effort (cpue) were used to test fishing rates and estimate the total quantity of oysters taken from select locations across periods of time. Catch quantities enabled calculation of the minimum number of oysters per hectare for two locations. These data were presented to government scientists, managers, and industry. As a result, interest in growing O. angasi increased and new areas for oyster aquaculture were included in regulatory zoning (spatial planning). Records of introductions of the non-native oyster Saccostrea glomerata, Sydney rock oysters, from 1866 through 1959, were also identified and used to evaluate the biosecurity risk of aquaculture for this species through semi-quantitative risk assessment. Although applications to culture S. glomerata in South Australia had previously been declined, the inclusion of historical data in risk assessment led to the conclusion that applications to culture this species would be accepted. The ex les presented here have been effectively incorporated into management processes and represent an important opportunity for the aquaculture industry in South Australia to ersify. This demonstrates that historical data can be used to inform planning and support industry, government, and societies in addressing challenges associated with aquaculture, as well as natural resource management more broadly.
Publisher: American Chemical Society (ACS)
Date: 24-10-2017
Abstract: Many marine organisms produce calcareous shells as the key structure for defense, but the functionality of shells may be compromised by ocean acidification and warming. Nevertheless, calcifying organisms may adaptively modify their shell properties in response to these impacts. Here, we examined how reduced pH and elevated temperature affect shell mechanical and geochemical properties of common grazing gastropods from intertidal to subtidal zones. Given the greater environmental fluctuations in the intertidal zone, we hypothesized that intertidal gastropods would exhibit more plastic responses in shell properties than subtidal gastropods. Overall, three out of five subtidal gastropods produced softer shells at elevated temperature, while intertidal gastropods maintained their shell hardness at both elevated pCO
Publisher: Elsevier BV
Date: 02-1997
Publisher: Springer Science and Business Media LLC
Date: 11-03-2009
Publisher: Springer Netherlands
Date: 2014
Publisher: Springer Science and Business Media LLC
Date: 19-03-2003
Publisher: Elsevier BV
Date: 08-2015
Publisher: Informa UK Limited
Date: 05-2005
Publisher: Inter-Research Science Center
Date: 22-10-2014
DOI: 10.3354/MEPS10916
Publisher: Elsevier BV
Date: 08-2013
DOI: 10.1016/J.MARPOLBUL.2013.01.031
Abstract: While carbon capture and storage (CCS) is increasingly recognised as technologically possible, recent evidence from deep-sea CCS activities suggests that leakage from reservoirs may result in highly CO2 impacted biological communities. In contrast, shallow marine waters have higher primary productivity which may partially mitigate this leakage. We used natural CO2 seeps in shallow marine waters to assess if increased benthic primary productivity could capture and store CO2 leakage in areas targeted for CCS. We found that the productivity of seagrass communities (in situ, using natural CO2 seeps) and two in idual species (ex situ, Cymodocea serrulata and Halophila ovalis) increased with CO2 concentration, but only species with dense belowground biomass increased in abundance (e.g. C. serrulata). Importantly, the ratio of below:above ground biomass of seagrass communities increased fivefold, making seagrass good candidates to partially mitigate CO2 leakage from sub-seabed reservoirs, since they form carbon sinks that can be buried for millennia.
Publisher: Wiley
Date: 15-06-2011
DOI: 10.1111/J.1529-8817.2011.01002.X
Abstract: Some abiotic conditions are well known to play disproportionately large roles in shaping contemporary assemblages, yet their roles may not continue to have similar magnitudes of effect into the future. We tested whether forecasted levels of CO2 could alter the strength of influence of an abiotic factor (i.e., light intensity) well known for its strength of influence on the subtidal ecology of photosynthetic organisms. We investigated these dynamics in two subtidal algal species that form contrasting associations with kelp forests, one negatively associated with kelp canopies (turf-forming brown algae, Feldmannia spp.) and the other positively associated with kelp as understory (calcifying red crustose algae, Lithophyllum sp.). Using an experimental approach, we assessed the independent and combined effects of [CO2 ] (control and elevated) and light (shade, low ultraviolet B [UVB], full light) on growth, recruitment, and relative electron transport rate (rETR). Under control [CO2 ], the effects of light corresponded to the relative light environments of the two groups of algae. The influence of light on the percentage cover and biomass of understory crusts was substantially reduced under elevated [CO2 ], which caused crusts to grow less. While elevated [CO2 ] had the opposite effect of positively influencing turf cover and biomass, it had the same effect of reducing the structuring effects of light and UVB. Hence, if we are to predict the ecological consequences of future CO2 conditions, the role of contemporary processes cannot be assumed to produce similar effects relative to other processes, which will change with a changing climate.
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.TREE.2017.06.011
Abstract: Good writing takes time, but in a research environment where speed is master, is it a superfluous pursuit? Scientists spend most of their working life writing, yet our writing style obstructs its key purpose: communication. We advocate more accessible prose that boosts the influence of our publications. For those who change, the proof of their success will be science that is read, understood, and remembered.
Publisher: Springer Science and Business Media LLC
Date: 27-03-1998
Publisher: Springer Science and Business Media LLC
Date: 19-03-2018
Publisher: Springer Science and Business Media LLC
Date: 14-01-2012
Publisher: Wiley
Date: 05-05-2021
DOI: 10.1111/EVA.13239
Abstract: Volcanic CO 2 seeps are natural laboratories that can provide insights into the adaptation of species to ocean acidification. While many species are challenged by reduced‐pH levels, some species benefit from the altered environment and thrive. Here, we explore the molecular mechanisms of adaptation to ocean acidification in a population of a temperate fish species that experiences increased population sizes under elevated CO 2 . Fish from CO 2 seeps exhibited an overall increased gene expression in gonad tissue compared with those from ambient CO 2 sites. Up‐regulated genes at CO 2 seeps are possible targets of adaptive selection as they can directly influence the physiological performance of fishes exposed to ocean acidification. Most of the up‐regulated genes at seeps were functionally involved in the maintenance of pH homeostasis and increased metabolism, and presented a deviation from neutral evolution expectations in their patterns of DNA polymorphisms, providing evidence for adaptive selection to ocean acidification. The targets of this adaptive selection are likely regulatory sequences responsible for the increased expression of these genes, which would allow a fine‐tuned physiological regulation to maintain homeostasis and thrive at CO 2 seeps. Our findings reveal that standing genetic variation in DNA sequences regulating the expression of genes in response to a reduced‐pH environment could provide for adaptive potential to near‐future ocean acidification in fishes. Moreover, with this study we provide a forthright methodology combining transcriptomics and genomics, which can be applied to infer the adaptive potential to different environmental conditions in wild marine populations.
Publisher: Wiley
Date: 10-05-2022
Abstract: Marine soundscapes provide navigational information for dispersing organisms, but with wide‐scale habitat loss, these soundscapes are becoming muted. Consequently, dispersing larvae that use soundscapes for navigation may be lost at sea, limiting the success of restoration efforts that rely upon the recruitment of dispersing organisms to restore habitat. Where limited larval supply constrains restoration efforts, using speakers to create gradients in healthy soundscapes could provide the navigational cue that attract larvae and enhances recruitment. Combining laboratory and field studies, we test whether broadcasting soundscapes might act as a directional cue for oysters targeted for national‐scale reef restoration the Australian flat oyster Ostrea angasi . In the laboratory, we tested whether settlement of larvae increases along a gradient of increasing sound intensity (8 m laboratory tank) versus a no sound control, and whether settlement increases with soundscapes that approximate healthy reefs. In the field, we tested the context dependency and magnitude of using boosted soundscapes for restoration practice in areas of low, medium and high background noise, by observing the settlement rates of naturally recruiting oysters at three restoration sites when exposed to boosted reef sound relative to ambient conditions. In the laboratory, we showed that 83% of larvae swim horizontally towards reef sound to settle in greater densities closer to its source, a near doubling of the larvae (44%) that dispersed in the no sound controls. Larval settlement increased by 300% in the presence of reef sound relative to controls in the laboratory. In the field, speakers increased larval settlement in localities of lower background noise. To our knowledge, this is the first evidence that oyster larvae can swim horizontally and choose to move towards a sound source. Synthesis and applications . We discovered that oyster larvae can swim horizontally towards reef sound and then settle in higher densities, relative to controls. Importantly, this effect of sound on recruitment is enhanced in localities of lower background noise. We propose that where recruitment is limited, restoration practitioners best use acoustic technology in localities of lower background noise to guide larvae to boost recovery.
Publisher: Springer Science and Business Media LLC
Date: 15-02-2005
Publisher: Springer Science and Business Media LLC
Date: 02-2004
Publisher: MDPI AG
Date: 10-10-2013
DOI: 10.3390/W5041653
Publisher: CSIRO Publishing
Date: 1998
DOI: 10.1071/MF97034
Abstract: Patterns of piscivory were investigated among five abundant species of predatory fish at One Tree Reef, Great Barrier Reef, Australia. The guts of two lutjanids Lutjanus carponotatus and Lutjanus fulviflamma, two labrids Cheilinus diagrammus and Thalassoma lunare, and a serranid Epinephelus quoyanus were examined for type, length, number and volume of prey at two times of the day: sunrise and sunset. Each of these species consumed fish, but only T. lunare and the two lutjanids consumed recruit-sized fish. This information is important because there is often scepticism as to whether large predators ( mm TL) such as lutjanids consume new recruits. Only in the lutjanids were there differences in the number and volume of prey present in the gut at sunrise and at sunset at sunset, few lutjanid specimens contained prey, whereas at sunrise 98% of specimens contained prey. This result, in conjunction with studies of nocturnal activity, suggest that patterns of predation pressure inferred from daylight observations of predator abundance may have little relevance to actual patterns of predation at local scales.
Publisher: Informa UK Limited
Date: 11-2005
Publisher: Springer Science and Business Media LLC
Date: 31-10-2013
DOI: 10.1007/S00442-012-2507-5
Abstract: Primary producers rarely exist under their ideal conditions, with key processes often limited by resource availability. As human activities modify environmental conditions, and therefore resource availability, some species may be released from these limitations while others are not, potentially disrupting community structure. In order to examine the limitations experienced by algal functional groups that characterise alternate community structures (i.e. turf-forming algae and canopy-forming kelp), we exposed these groups to contemporary and enriched levels of carbon dioxide (CO2) and nutrients. Turfs responded to the in idual enrichment of both CO2 and nutrients, with the greatest shift in the biomass and carbon:nitrogen (C:N) ratios observed under their combined enrichment. In contrast, kelp responded to enriched nutrients, but not enriched CO2. We hypothesise that the differing limitations reflect the contrasting physiologies of these functional groups, specifically their methods of C acquisition, such as the possession and/or efficiency of a carbon concentrating mechanism (CCM). Importantly, our results reveal that these functional groups, whose interactions structure entire communities, experience distinct resource limitations, with some potentially limited by a single type of resource (i.e. kelp by nutrients), while others may be co-limited (i.e. turf by CO2 and nutrients). Consequently, the identification of how alternate conditions modify resource availability and limitations may facilitate anticipation of the future sustainability of major ecosystem components and the communities they support.
Publisher: Inter-Research Science Center
Date: 23-10-2006
DOI: 10.3354/MEPS324127
Publisher: Public Library of Science (PLoS)
Date: 23-03-2012
Publisher: Wiley
Date: 30-10-2008
Publisher: Elsevier BV
Date: 08-2018
DOI: 10.1016/J.MARPOLBUL.2018.06.004
Abstract: Long-term species responses to ocean acidification depend on their sensitivity during different life stages. We tested for sensitivity of juvenile fish behaviour to ocean acidification by exposing eggs to control and elevated CO
Publisher: Wiley
Date: 07-08-2022
Abstract: Ocean acidification is considered detrimental to marine calcifiers, but mounting contradictory evidence suggests a need to revisit this concept. This systematic review and meta‐analysis aim to critically re‐evaluate the prevailing paradigm of negative effects of ocean acidification on calcifiers. Based on 5153 observations from 985 studies, many calcifiers (e.g., echinoderms, crustaceans, and cephalopods) are found to be tolerant to near‐future ocean acidification (pH ≈ 7.8 by the year 2100), but coccolithophores, calcifying algae, and corals appear to be sensitive. Calcifiers are generally more sensitive at the larval stage than adult stage. Over 70% of the observations in growth and calcification are non‐negative, implying the acclimation capacity of many calcifiers to ocean acidification. This capacity can be mediated by phenotypic plasticity (e.g., physiological, mineralogical, structural, and molecular adjustments), transgenerational plasticity, increased food availability, or species interactions. The results suggest that the impacts of ocean acidification on calcifiers are less deleterious than initially thought as their adaptability has been underestimated. Therefore, in the forthcoming era of ocean acidification research, it is advocated that studying how marine organisms persist is as important as studying how they perish, and that future hypotheses and experimental designs are not constrained within the paradigm of negative effects.
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/MF05042
Abstract: Intraspecific variation in morphology is common among marine algae and may allow plants to exist across a wide geography and range of environmental conditions. Morphological variation of Ecklonia radiata has been described over thousands of kilometres of the temperate Australian coastline however, the degree to which this morphological variability is related to geographic and environmental variation is unknown. We tested the hypotheses that: (1) variation in the morphology of Ecklonia radiata, growing in both monospecific and mixed stands, is related to variation in latitude, longitude, wave exposure, temperature, depth and plant density (collectively referred to as ‘physical variables’) and (2) measures of morphological dissimilarity in E. radiata are greatest among locations that are separated by the largest geographic distances. The combined effect of the physical variables accounted for 74% of the variation in both monospecific and mixed stands. The majority of this variation was related to longitude and the remainder to wave exposure, water temperature and plant density. In monospecific stands, measures of morphological dissimilarity were consistently large between locations that were separated by the greatest geographical distances ( km). The existence of such relationships may not indicate causality, but do contribute to a broad based understanding of major ecological patterns across temperate Australia’s coastline.
Publisher: Elsevier BV
Date: 06-2016
Publisher: Wiley
Date: 13-01-2022
DOI: 10.1111/GCB.16052
Abstract: Ocean acidification can cause dissolution of calcium carbonate minerals in biological structures of many marine organisms, which can be exacerbated by warming. However, it is still unclear whether this also affects organisms that have body parts made of calcium phosphate minerals (e.g. shark teeth), which may also be impacted by the ‘corrosive’ effect of acidified seawater. Thus, we examined the effect of ocean acidification and warming on the mechanical properties of shark teeth (Port Jackson shark, Heterodontus portusjacksoni ), and assessed whether their mineralogical properties can be modified in response to predicted near‐future seawater pH (–0.3 units) and temperature (+3°C) changes. We found that warming resulted in the production of more brittle teeth (higher elastic modulus and lower mechanical resilience) that were more vulnerable to physical damage. Yet, when combined with ocean acidification, the durability of teeth increased (i.e. less prone to physical damage due to the production of more elastic teeth) so that they did not differ from those raised under ambient conditions. The teeth were chiefly made of fluorapatite (Ca 5 (PO 4 ) 3 F), with increased fluoride content under ocean acidification that was associated with increased crystallinity. The increased precipitation of this highly insoluble mineral under ocean acidification suggests that the sharks could modulate and enhance biomineralization to produce teeth which are more resistant to corrosion. This adaptive mineralogical adjustment could allow some shark species to maintain durability and functionality of their teeth, which underpins a fundamental component of predation and sustenance of the trophic dynamics of future oceans.
Publisher: Springer Science and Business Media LLC
Date: 10-08-2016
DOI: 10.1038/NCLIMATE2757
Publisher: Springer Science and Business Media LLC
Date: 25-09-2023
Publisher: Elsevier BV
Date: 08-2008
Publisher: Wiley
Date: 11-08-2008
Publisher: Elsevier BV
Date: 05-2000
DOI: 10.1016/S0022-0981(00)00147-7
Abstract: Urban structures in the form of pontoons and pilings represent major coastal habitats for marine organisms and understanding the factors causing abundances of organisms to differ between these and natural habitat has been neglected in the study of coastal ecology. It has been proposed that composition of substrata explain differences previously described between subtidal assemblages of epibiota on rocky reef (sandstone) and pontoons (concrete) in Sydney Harbour, Australia. This study tested the hypothesis that differences in the composition of substratum (sandstone vs. concrete) independent of type of habitat (rocky reef vs. pontoon) affects the development of epibiotic assemblages. This was tested by experimentally providing substratum of the two types in both habitats. Epibiotic assemblages were unaffected by the composition of substratum but strongly affected by the type of habitat demonstrating that pontoons constitute novel habitats for epibiota. This result highlights a need for determining how current ecological understanding of subtidal epibiota, which is heavily based on studies of urban structures (pilings and pontoons), relates to natural reef. Future tests of hypotheses about the nature of these differences will not only contribute to better ecological understanding of epibiota and their use of urban structures as habitats, but also to better predictions of future changes to the ecology of coastal habitats.
Publisher: Elsevier BV
Date: 04-2011
Publisher: Elsevier BV
Date: 07-2002
Publisher: Springer Science and Business Media LLC
Date: 05-01-2012
Publisher: Elsevier BV
Date: 10-2013
Publisher: Inter-Research Science Center
Date: 09-01-2014
DOI: 10.3354/MEPS10513
Publisher: Springer Science and Business Media LLC
Date: 21-11-2017
DOI: 10.1038/NCLIMATE3161
Publisher: SAGE Publications
Date: 08-1996
Abstract: A s le of 630 Victorian university students, aged between 17 and 24, completed a questionnaire on knowledge of sexually transmitted diseases (STDs). Overall students demonstrated moderate levels of knowledge about the names of diseases which are transmitted by sexual contact, symptoms and medical facts and transmission modes of common STDs. However, they had more knowledge about the labels than they did about symptoms and transmission modes and were misinformed about certain clinical aspects of STDs. It was found that the different levels of knowledge varied with the type of STD. Knowledge about symptoms or transmission did not correlate with a disease's incidence or clinical aspects. Sexual experience and having an Australian born mother correlated with higher scores. This study suggests that young people do not have high levels of knowledge about common STDs they may encounter. Identification of a label is of limited personal value if there is no concurrent knowledge about disease transmission and prognosis.
Publisher: Elsevier BV
Date: 08-2011
Publisher: Informa UK Limited
Date: 12-1999
Publisher: Wiley
Date: 02-2001
Publisher: Informa UK Limited
Date: 2010
DOI: 10.1080/08927010903174599
Abstract: This study experimentally determined the effect of different vessel voyage speeds (5, 10 and 18 knots = 2.6, 5.1 and 9.3 ms(-1), respectively) and morphological characteristics including growth form (solitary or colonial), profile (erect or encrusting) and structure (soft, hard or flexible) on the survival of a range of common biofouling organisms. A custom built hydrodynamic keel attached to the bottom of a 6 m aluminium powerboat was used to subject pre-fouled settlement plates for this purpose. Vessel speeds of 5 and 10 knots had little effect on the species richness of biofouling assemblages tested, however richness decreased by 50% following 18 knots treatments. Species percentage cover decreased with increasing speed across all speed treatments and this decrease was most pronounced at 10 and 18 knots, with cover reduced by 24 and 85% respectively. Survival was greatest for organisms with colonial, encrusting, hard and/or flexible morphological characteristics, and this effect increased with increasing speed. This study suggests that there is predictive power in forecasting future introductions if we can understand the extent to which such traits explain the world-wide distributions of non-indigenous species. Future introductions are a certainty and can only provide an increasing source of new information on which to test the validity of these predications.
Publisher: Wiley
Date: 07-2009
DOI: 10.1890/08-0831.1
Abstract: Spatial subsidies are considered strong where differences in resource availability between donor and recipient systems are greatest. We tested whether human activities on land can increase subsidies of terrigenous nitrogen to open rocky coasts and whether these differences can predict apparent deforestation of kelp forests. We first identified landscape-scale variation in the human-mediated transfer of dissolved inorganic nitrogen (DIN) from natural, agricultural, and urban catchments to temperate coasts after episodes of rainfall. Compared to natural catchments, subsidies of DIN were on average 8-407 times greater in urban catchments, and 1-63 times greater in agricultural catchments. Urban derived nitrogen was attributed to the release of sewage effluent, as delineated by delta15N isotopic values of transplanted algae. Having made this link, we then assessed whether this catchment-scale variation may account for variation in structure of subtidal habitats, particularly as related to theory of nutrient-driven shifts of habitat from perennial (i.e., canopy-forming algae) to opportunistic species (i.e., turf-forming algae). We not only detected patterns consistent with this theory, but also established that the size and total proportion of patches of turf-forming algae were greater where the ratio of donor: recipient nitrogen loads was greater (i.e., size of subsidy). An important realization was that deforestation may be more strongly related to variation in the size of subsidy rather than size of human populations, particularly among urban catchments. These data directly link the type of human activity within catchments to the modification of land-to-sea subsidies and indirectly support theory that predicts terrestrial inputs to have greater ecological effects where the disparity in resource availability between donor and recipient is exacerbated. Our evidence has been used by coastal managers to reconsider their management of coastal systems and has subsequently contributed to new water-recycling policy and initiatives.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 08-01-2010
Publisher: Wiley
Date: 14-01-2015
DOI: 10.1111/COBI.12452
Abstract: Oyster reefs form over extensive areas and the ersity and productivity of sheltered coasts depend on them. Due to the relatively recent population growth of coastal settlements in Australia, we were able to evaluate the collapse and extirpation of native oyster reefs (Ostrea angasi) over the course of a commercial fishery. We used historical records to quantify commercial catch of O. angasi in southern Australia from early colonization, around 1836, to some of the last recorded catches in 1944 and used our estimates of catch and effort to map their past distribution and assess oyster abundance over 180 years. Significant declines in catch and effort occurred from 1886 to 1946 and no native oyster reefs occur today, but historically oyster reefs extended across more than 1,500 km of coastline. That oyster reefs were characteristic of much of the coastline of South Australia from 1836 to 1910 appears not to be known because there is no contemporary consideration of their ecological and economic value. Based on the concept of a shifted baseline, we consider this contemporary state to reflect a collective, intergenerational amnesia. Our model of generational amnesia accounts for differences in intergenerational expectations of food, economic value, and ecosystem services of nearshore areas. An ecological system that once surrounded much of the coast and possibly the past presence of oyster reefs altogether may be forgotten and could not only undermine progress towards their recovery, but also reduce our expectations of these coastal ecosystems.
Publisher: Elsevier BV
Date: 11-2018
Publisher: Springer Science and Business Media LLC
Date: 21-05-2012
DOI: 10.1038/SREP00413
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/MF08268
Abstract: Characterising patterns of dispersal and gene flow in habitat-forming organisms is becoming a focal concern for conservation and management strategies as anthropogenic impacts drive change in coastal ecosystems. Here, we use six microsatellite markers to characterise dispersal and gene flow across the South Australian distribution of the habitat-forming kelp Ecklonia radiata. Populations of E. radiata on subtidal reefs in South Australia were highly genetically structured on large (100s of km, FST = 0.211) and small (10s of km, FST = 0.042) spatial scales with the extent of differentiation positively correlated with geographic distances among populations. Neither the presence of oceanic currents nor intervening rocky reef habitats appeared to facilitate widespread gene flow. There was a trend for island populations to be more genetically differentiated from those on the mainland and to have slightly greater levels of heterozygosity than mainland populations. Our results show relatively low dispersal and gene flow suggesting that recovery following kelp loss may be slow. Such information not only provides insights into relative rates of recovery, but may also identify which populations may be best used for propagation and restoration efforts.
Publisher: Elsevier BV
Date: 04-2007
Publisher: University of Chicago Press
Date: 06-2008
DOI: 10.1086/590641
Publisher: Wiley
Date: 12-1998
Publisher: Elsevier BV
Date: 04-2005
Publisher: Elsevier BV
Date: 2012
Publisher: Inter-Research Science Center
Date: 2005
DOI: 10.3354/MEPS299079
Publisher: The Royal Society
Date: 05-01-2015
Abstract: A pronounced, widespread and persistent regime shift among marine ecosystems is observable on temperate rocky reefs as a result of sea urchin overgrazing. Here, we empirically define regime-shift dynamics for this grazing system which transitions between productive macroalgal beds and impoverished urchin barrens. Catastrophic in nature, urchin overgrazing in a well-studied Australian system demonstrates a discontinuous regime shift, which is of particular management concern as recovery of desirable macroalgal beds requires reducing grazers to well below the initial threshold of overgrazing. Generality of this regime-shift dynamic is explored across 13 rocky reef systems (spanning 11 different regions from both hemispheres) by compiling available survey data (totalling 10 901 quadrats surveyed in situ ) plus experimental regime-shift responses (observed during a total of 57 in situ manipulations). The emergent and globally coherent pattern shows urchin grazing to cause a discontinuous ‘catastrophic’ regime shift, with hysteresis effect of approximately one order of magnitude in urchin biomass between critical thresholds of overgrazing and recovery. Different life-history traits appear to create asymmetry in the pace of overgrazing versus recovery. Once shifted, strong feedback mechanisms provide resilience for each alternative state thus defining the catastrophic nature of this regime shift. Importantly, human-derived stressors can act to erode resilience of desirable macroalgal beds while strengthening resilience of urchin barrens, thus exacerbating the risk, spatial extent and irreversibility of an unwanted regime shift for marine ecosystems.
Publisher: Wiley
Date: 27-04-2017
DOI: 10.1111/GCB.13699
Abstract: Future climate is forecast to drive bottom-up (resource driven) and top-down (consumer driven) change to food web dynamics and community structure. Yet, our predictive understanding of these changes is h ered by an over-reliance on simplified laboratory systems centred on single trophic levels. Using a large mesocosm experiment, we reveal how future ocean acidification and warming modify trophic linkages across a three-level food web: that is, primary (algae), secondary (herbivorous invertebrates) and tertiary (predatory fish) producers. Both elevated CO
Publisher: Wiley
Date: 04-03-2020
DOI: 10.1111/REC.13134
Publisher: MDPI AG
Date: 16-08-2010
DOI: 10.3390/SU2082593
Publisher: Wiley
Date: 05-2018
DOI: 10.1002/ECY.2209
Abstract: Ecologically dominant species often define ecosystem states, but as human disturbances intensify, their subordinate counterparts increasingly displace them. We consider the duality of disturbance by examining how environmental drivers can simultaneously act as a stressor to dominant species and as a resource to subordinates. Using a model ecosystem, we demonstrate that CO
Publisher: Wiley
Date: 26-09-2018
DOI: 10.1111/DDI.12767
Publisher: Elsevier BV
Date: 04-2011
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/MF15232
Abstract: Kelp forests define km of temperate coastline across southern Australia, where ~70% of Australians live, work and recreate. Despite this, public and political awareness of the scale and significance of this marine ecosystem is low, and research investment miniscule ( %), relative to comparable ecosystems. The absence of an identity for Australia’s temperate reefs as an entity has probably contributed to the current lack of appreciation of this system, which is at odds with its profound ecological, social and economic importance. We define the ‘Great Southern Reef’ (GSR) as Australia’s spatially connected temperate reef system. The GSR covers ~71000km2 and represents a global bio ersity hotspot across at least nine phyla. GSR-related fishing and tourism generates at least AU$10 billion year–1, and in this context the GSR is a significant natural asset for Australia and globally. Maintaining the health and ecological functioning of the GSR is critical to the continued sustainability of human livelihoods and wellbeing derived from it. By recognising the GSR as an entity we seek to boost awareness, and take steps towards negotiating the difficult challenges the GSR faces in a future of unprecedented coastal population growth and global change.
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/MF14266
Abstract: The capacity of natural systems to resist environmental change underpins ecosystem stability, e.g. the persistence of kelp-dominated states which are sometimes displaced by subordinates or weedy species (i.e. algal turfs). Perturbation by resource enhancement at global (e.g. CO2 emissions) through local scales (e.g. nutrient pollution) increases the probability of turf domination, yet these same resources stimulate an increase in per capita consumption of turfs by herbivores. We test whether such resource perturbation can stimulate herbivores to absorb the additional productivity of turfs that cause kelp displacement. We tested the hypotheses that (1) elevated nitrogen (N) and carbon dioxide (CO2) not only stimulate an increase in consumptive rates, but also stimulate an increase in underlying metabolic rates of gastropod herbivores, so that (2) enhanced primary productivity is countered by herbivory. We reveal that elevated nitrogen and CO2 stimulated an elevation in rates of consumption in proportion to an increase in metabolic rate of grazers. Subsequently, grazers consumed proportionately greater cover of turfs to counter turf expansion. Resource enrichment, therefore, can stimulate metabolic and consumptive activity of herbivores to absorb the additional productivity of opportunistic species. Hence, the competitive potential of subordinates to displace community dominants may be checked by the very resources that otherwise drive instability.
Publisher: Elsevier BV
Date: 07-2000
DOI: 10.1016/S0022-0981(00)00181-7
Abstract: Coastal marine ecology is, quite properly, increasingly focussed on experimental tests of hypotheses about processes. These are, however, done to explain observations and patterns. It is therefore appropriate to be able to publish quantitative observations to provide the context and basis for studying mechanisms and processes. Ecologists are concerned about very different types of observations. Some areas of study are still totally dependent on observational, descriptive evidence some depend on mensurative tests of hypotheses about patterns. Tests of hypotheses about patterns are also needed to validate casual or qualitative observations. Guide-lines for what constitutes appropriate or publishable ecological descriptions are discussed here. These recognize the experimental, hypothesis-testing nature of many descriptive studies and consider the relevance of sound logic and experimental design in the planning, collection and interpretation of observations.
Publisher: Springer Science and Business Media LLC
Date: 11-04-2018
DOI: 10.1038/S41598-018-24026-6
Abstract: Population replenishment of marine life largely depends on successful dispersal of larvae to suitable adult habitat. Ocean acidification alters behavioural responses to physical and chemical cues in marine animals, including the maladaptive deterrence of settlement-stage larval fish to odours of preferred habitat and attraction to odours of non-preferred habitat. However, sensory compensation may allow fish to use alternative settlement cues such as sound. We show that future ocean acidification reverses the attraction of larval fish (barramundi) to their preferred settlement sounds (tropical estuarine mangroves). Instead, acidification instigates an attraction to unfamiliar sounds (temperate rocky reefs) as well as artificially generated sounds (white noise), both of which were ignored by fish living in current day conditions. This finding suggests that by the end of the century, following a business as usual CO 2 emission scenario, these animals might avoid functional environmental cues and become attracted to cues that provide no adaptive advantage or are potentially deleterious. This maladaptation could disrupt population replenishment of this and other economically important species if animals fail to adapt to elevated CO 2 conditions.
Publisher: Wiley
Date: 07-07-2021
DOI: 10.1002/EAP.2386
Abstract: Humanity’s ambitions to revive ecosystems at large scales require solutions to move restoration efforts beyond the small scale. There are increasing calls for technological solutions to reduce costs and facilitate large‐scale restoration through the use of emerging technologies using an adaptive process of research and development. We show how technological enrichment of marine soundscapes may provide a solution that repairs the recruitment process to accelerate the recovery of lost marine habitats. This solution would solve the problems of current practice that largely relies upon natural recruitment processes, which carries considerable risk where recruitment is variable or eroded. By combining the literature with laboratory experiments, we describe evidence for “highways of sound” that convey navigable information for dispersing life stages in search for adult habitat. We show that these navigational cues tend to be silenced as their habitat is lost, creating negative feedbacks that hinders restoration. We suggest that reprovisioning soundscapes using underwater technology offers the potential to reverse this feedback and entice target organisms to recruit in greater densities. Collective evidence indicates that the application of soundscape theory and technology may unlock the recruitment potential needed to trigger the recruitment of target organisms and the natural soundscapes they create at large scales.
Publisher: Springer Science and Business Media LLC
Date: 06-09-2014
DOI: 10.1007/S00442-014-3054-Z
Abstract: Increased availability of dissolved CO2 in the ocean can enhance the productivity and growth of marine plants such as seagrasses and algae, but realised benefits may be contingent on additional conditions (e.g. light) that modify biotic interactions between these plant groups. The combined effects of future CO2 and differing light on the growth of seagrass and their algal epiphytes were tested by maintaining juvenile seagrasses Amphibolis antarctica under three different CO2 concentrations representing ambient, moderate future and high future forecasts (i.e. 390, 650 vs. 900 µl l(-1)) and two light levels representing low and high PAR (i.e. 43 vs. 167 µmol m(-2) s(-1)). Aboveground and belowground biomass, leaf growth, epiphyte cover, tissue chemistry and photosynthetic parameters of seagrasses were measured. At low light, there was a neutral to positive effect of elevated CO2 on seagrass biomass and growth at high light, this effect of CO2 switched toward negative, as growth and biomass decreased at the highest CO2 level. These opposing responses to CO2 appeared to be closely linked to the overgrowth of seagrass by filamentous algal epiphytes when high light and CO2 were combined. Importantly, all seagrass plants maintained positive leaf growth throughout the experiment, indicating that growth was inhibited by some experimental conditions but not arrested entirely. Therefore, while greater light or elevated CO2 provided direct physiological benefits for seagrasses, such benefits were likely negated by overgrowth of epiphytic algae when greater light and CO2 were combined. This result demonstrates how indirect ecological effects from epiphytes can modify independent physiological predictions for seagrass associated with global change.
Publisher: Wiley
Date: 08-2012
Publisher: Public Library of Science (PLoS)
Date: 12-12-2012
Publisher: Wiley
Date: 26-05-2004
Publisher: Wiley
Date: 05-12-2013
DOI: 10.1002/ECE3.893
Publisher: CSIRO Publishing
Date: 2014
DOI: 10.1071/MF13246
Abstract: Decreases in the mean trophic level (MTL) of fishery catches have been used to infer reductions in the abundance of high trophic level species caused by fishing pressure. Previous assessments of southern Australian fisheries have been inconclusive. The objectives of the present study were to provide more accurate estimates of MTL using disaggregated taxonomic and spatial data. We applied the model of MTL to fisheries catch statistics for the state of South Australia from 1951 to 2010 and a novel set of historical market data from 1936 to 1946. Results show that from 1951 to 2010, MTL declined by 0.16 of a trophic level per decade a rate greater than the global average of 0.10 but equivalent to similar regional investigations in other areas. This change is mainly attributable to large increases in catches of sardine, rather than reductions in the catches of high trophic level species. The pattern is maintained when the historical data is included, providing a time line from 1936 to 2010. Our results show a broadening of the catch of lower trophic levels and suggest care in interpretation of MTL of catches because reductions do not necessarily reflect change in high trophic level species by fishing pressure.
Publisher: Wiley
Date: 28-06-2017
DOI: 10.1002/ECE3.3164
Publisher: Elsevier BV
Date: 10-2017
DOI: 10.1016/J.MARENVRES.2017.09.011
Abstract: Artificial structures will be increasingly utilized to protect coastal infrastructure from sea-level rise and storms associated with climate change. Although it is well documented that the materials comprising artificial structures influence the composition of organisms that use them as habitat, little is known about how these materials may chemically react with changing seawater conditions, and what effects this will have on associated biota. We investigated the effects of ocean warming, acidification, and type of coastal infrastructure material on algal turfs. Seawater acidification resulted in greater covers of turf, though this effect was counteracted by elevated temperatures. Concrete supported a greater cover of turf than granite or high-density polyethylene (HDPE) under all temperature and pH treatments, with the greatest covers occurring under simulated ocean acidification. Furthermore, photosynthetic efficiency under acidification was greater on concrete substratum compared to all other materials and treatment combinations. These results demonstrate the capacity to maximise ecological benefits whilst still meeting local management objectives when engineering coastal defense structures by selecting materials that are appropriate in an ocean change context. Therefore, mitigation efforts to offset impacts from sea-level rise and storms can also be engineered to alter, or even reduce, the effects of climatic change on biological assemblages.
Publisher: Wiley
Date: 20-12-2013
Publisher: Elsevier BV
Date: 03-2016
Publisher: Wiley
Date: 26-11-2009
DOI: 10.1111/J.1365-2664.2009.01711.X
Abstract: 1. Policy initiatives that seek to recover lost habitats require the capacity to anticipate and suppress the mechanisms that drive loss. The replacement of forested landscapes by simple landscapes comprising of opportunistic or ‘weedy’ species represents an increasingly common phenomenon across human‐dominated systems. The failure of subtidal forests to recover from natural and human disturbance and their ultimate replacement by degraded habitats is recognized globally. The current lack of knowledge on whether such shifts can be reversed jeopardizes considerations of restoration policy within increasingly human‐dominated landscapes. 2. We critically assessed the model that recovery of canopies within remnant kelp forests in degraded landscapes (i.e. turf‐forming algae that carpet space) is slower than in adjacent forested landscapes, but may be increased by removing turfs. 3. After generating experimental disturbance, canopies recovered to their former state within forested landscapes, but not in remnant forests in degraded landscapes. Removal of turfs from spaces between remnant forests, however, enabled canopies to recruit and subsequently develop covers that matched those in remnant forests. 4. Whilst the supply of canopy‐forming propagules to degraded landscapes is likely to decline with gap expansion, we show that improvements to forest resilience and restoration are possible via policies that result in a reduction of turf covers. These results also support the model that regime‐shifts need not be a product of synchronized loss, but can occur as a result of reduced rates of canopy‐recruitment over broad areas and many years. Indeed, patterns of canopy‐loss over several decades redouble attention to the human‐mediated conditions that enable turfs to retain space (i.e. elevated nutrient and sediment loads via coastal runoff). 5. Synthesis and applications . We demonstrate that future restoration is a possible outcome of polices that promote ecosystem recovery. In doing so, we reduce uncertainty about policy initiatives that aim to upgrade the recycling potential of wastewater treatment plants (e.g. nearly 45% of South Australia’s metropolitan wastewater) to improve the quality of water needed to restore subtidal forests. Uncertainty about resilience‐building and restoration management are redressed by demonstrating that the feedbacks maintaining regime‐shifted landscapes are not necessarily permanent.
Publisher: Inter-Research Science Center
Date: 21-04-2008
DOI: 10.3354/MEPS07329
Publisher: Elsevier BV
Date: 08-2001
DOI: 10.1016/S0141-1136(00)00266-X
Abstract: There remains little understanding of the relationship between the ecologies of urban habitats (pilings and pontoons) and natural habitats (rocky reef) for sessile plants and animals (epibiota) living on urbanised coasts. This study describes the structure of subtidal assemblages of epibiota among pilings, pontoons and adjacent rocky reef in Sydney Harbour, Australia. I tested the prediction that the experimental provision of substrata of the same age and composition in all three habitats would produce assemblages that: (1) differed among all three habitats and (2) differed most on floating pontoons relative to the two fixed habitats (pilings and reef). As predicted, the results suggested that both pilings and pontoons, particularly the latter, create novel habitats for epibiotic assemblages independent of age and composition of substratum. It is not fully understood why these urban structures act as such different habitats from natural rocky reefs. The important point is that they are different and we are yet to understand the implications of this for the ecology of coastal areas subject to urbanisation.
Publisher: Springer Science and Business Media LLC
Date: 14-09-2016
DOI: 10.1038/SREP33383
Abstract: When conditions are stressful, reproduction and population growth are reduced, but when favourable, reproduction and population size can boom. Theory suggests climate change is an increasingly stressful environment, predicting extinctions or decreased abundances. However, if favourable conditions align, such as an increase in resources or release from competition and predation, future climate can fuel population growth. Tests of such population growth models and the mechanisms by which they are enabled are rare. We tested whether intergenerational increases in population size might be facilitated by adjustments in reproductive success to favourable environmental conditions in a large-scale mesocosm experiment. Herbivorous hipod populations responded to future climate by increasing 20 fold, suggesting that future climate might relax environmental constraints on fecundity. We then assessed whether future climate reduces variation in mating success, boosting population fecundity and size. The proportion of gravid females doubled, and variance in phenotypic variation of male secondary sexual characters (i.e. gnathopods) was significantly reduced. While future climate can enhance in idual growth and survival, it may also reduce constraints on mechanisms of reproduction such that enhanced intra-generational productivity and reproductive success transfers to subsequent generations. Where both intra and intergenerational production is enhanced, population sizes might boom.
Publisher: Elsevier BV
Date: 10-1991
Publisher: Springer Science and Business Media LLC
Date: 15-01-2008
Publisher: Oxford University Press (OUP)
Date: 27-11-2014
Publisher: Elsevier BV
Date: 12-2017
Publisher: Wiley
Date: 09-2016
DOI: 10.1002/ECY.1488
Abstract: The problem of linking fine-scale processes to broad-scale patterns remains a central challenge of ecology. As rates of abiotic change intensify, there is a critical need to understand how in idual responses aggregate to generate compensatory dynamics that stabilize community processes. Notably, while local and global resource enhancement (e.g., nutrient and CO
Publisher: MDPI AG
Date: 24-06-2020
Abstract: The ocean provides resources key to human health and well-being, including food, oxygen, livelihoods, blue spaces, and medicines. The global threat to these resources posed by accelerating ocean acidification is becoming increasingly evident as the world’s oceans absorb carbon dioxide emissions. While ocean acidification was initially perceived as a threat only to the marine realm, here we argue that it is also an emerging human health issue. Specifically, we explore how ocean acidification affects the quantity and quality of resources key to human health and well-being in the context of: (1) malnutrition and poisoning, (2) respiratory issues, (3) mental health impacts, and (4) development of medical resources. We explore mitigation and adaptation management strategies that can be implemented to strengthen the capacity of acidifying oceans to continue providing human health benefits. Importantly, we emphasize that the cost of such actions will be dependent upon the socioeconomic context specifically, costs will likely be greater for socioeconomically disadvantaged populations, exacerbating the current inequitable distribution of environmental and human health challenges. Given the scale of ocean acidification impacts on human health and well-being, recognizing and researching these complexities may allow the adaptation of management such that not only are the harms to human health reduced but the benefits enhanced.
Publisher: Informa UK Limited
Date: 09-2002
Publisher: Elsevier BV
Date: 11-2019
Publisher: Elsevier BV
Date: 08-1999
Publisher: Elsevier BV
Date: 02-2017
DOI: 10.1016/J.CUB.2016.12.004
Abstract: Reduction in seawater pH due to rising levels of anthropogenic carbon dioxide (CO
Publisher: Wiley
Date: 25-10-2022
Abstract: Marine soundscapes provide important navigational cues to dispersing larvae in search of suitable habitat. Yet, widespread habitat loss has degraded marine soundscapes and their functional role in recruitment. Habitat restoration efforts can provide suitable substrate for habitat regeneration, such as constructing reefs to facilitate recruitment and habitat growth by oysters, but typically occur where soundscapes are degraded and recruitment is limited. Enhancing marine soundscapes on newly constructed reefs using speaker technology may ensure sufficient recruitment to establish a trajectory of recovery for the desired habitat. Across two of the largest oyster reef restorations in Australia, we deployed low‐cost marine speakers at four sites and at three times throughout the recruitment season to test whether soundscape enrichment could boost recruitment and habitat formation by oysters. In the presence and absence of soundscape playback, we compared oyster recruitment rates to settlement panels across space and time, and oyster habitat cover and three‐dimensional habitat building on newly constructed boulder reefs. On the settlement panels deployed across the two reef restorations, soundscape playback significantly increased oyster recruitment at 8 of the 10 sites by an average (±1 SE) 5.1 ± 1.9 times (5281 ± 1384 more larvae per m 2 ), and by as much as 18 times. On boulders atop newly constructed reefs, where the restoration goal is for oysters to form three‐dimensional habitat, the surface area covered by oysters after 5 months did not differ between speaker and control treatments. However, soundscape playback appeared to influence the earlier recruitment of oysters, resulting in significantly more large oysters per boulder that formed significantly more three‐dimensional habitat building by an average 4.3 ± 1.2 times relative to nonspeaker controls. Synthesis and applications . Our results show that using speakers to enrich marine soundscapes at new restoration sites can boost oyster recruitment, resulting in more larger oysters that form more three‐dimensional habitat atop reef restorations. In accelerating the formation of these vertical growth forms, which provide the ecological functions that motivate restoration efforts, the early application of speaker technology on new reef restorations may help steer ecological succession on a trajectory of desired habitat recovery, potentially reducing the substantial cost of ongoing intervention.
Publisher: Informa UK Limited
Date: 1995
Publisher: Wiley
Date: 28-07-2017
DOI: 10.1111/COBI.12951
Abstract: Although the public desire for healthy environments is clear-cut, the science and management of ecosystem health has not been as simple. Ecological systems can be dynamic and can shift abruptly from one ecosystem state to another. Such unpredictable shifts result when ecological thresholds are crossed that is, small cumulative increases in an environmental stressor drive a much greater change than could be predicted from linear effects, suggesting an unforeseen tipping point is crossed. In coastal waters, broad-scale seagrass loss often occurs as a sudden event associated with human-driven nutrient enrichment (eutrophication). We tested whether the response of seagrass ecosystems to coastal nutrient enrichment is subject to a threshold effect. We exposed seagrass plots to different levels of nutrient enrichment (dissolved inorganic nitrogen) for 10 months and measured net production. Seagrass response exhibited a threshold pattern when nutrient enrichment exceeded moderate levels: there was an abrupt and large shift from positive to negative net leaf production (from approximately 0.04 leaf production to 0.02 leaf loss per day). Epiphyte load also increased as nutrient enrichment increased, which may have driven the shift in leaf production. Inadvertently crossing such thresholds, as can occur through ineffective management of land-derived inputs such as wastewater and stormwater runoff along urbanized coasts, may account for the widely observed sudden loss of seagrass meadows. Identification of tipping points may improve not only adaptive-management monitoring that seeks to avoid threshold effects, but also restoration approaches in systems that have crossed them.
Publisher: Wiley
Date: 25-11-2010
Publisher: Elsevier BV
Date: 09-2015
DOI: 10.1016/J.TREE.2015.06.014
Abstract: Ecologists seem predisposed to studying change because we are intuitively interested in dynamic systems, including their vulnerability to human disturbance. We contrast this disposition with the value of studying processes that work against change. Although powerful, processes that counter disturbance often go unexplored because they yield no observable community change. This stability results from compensatory processes which are initiated by disturbance these adjust in proportion to the strength of the disturbance to prevent community change. By recognising such buffering processes, we might also learn to recognise the early warning signals of community shifts which are notoriously difficult to predict because communities often show little to no change before their tipping point is reached.
Publisher: Wiley
Date: 16-09-2019
DOI: 10.1111/COBI.13403
Abstract: Environmental solutions require a decision‐making process that is ultimately political, in that they involve decisions with uncertain outcomes and stakeholders with conflicting viewpoints. If this process seeks broad alignment between the government and public, then reconciling conflicting viewpoints is a key to the legitimacy of these decisions. We show that ecological baselines can be particularly powerful tools for creating a common understanding for public support (legitimacy) and conformity to new rules or regulations (legality) that enable the solution. They are powerful because they move the discussion of solutions from the abstract to the concrete by providing a conceptual model for a common expectation (e.g., restoring habitat). They provide narratives of the past (ecological histories) that readjust the future expectations of in iduals on how to perceive and respond to new policy. While ecological baselines offer scientists benchmarks for reinstating ecological functions, they also normalize public and government discussion of solutions. This social normalization of public issues may assist government policy and influence social views, practices, and behaviors that adopt the policy. For science to more effectively inform conservation, we encourage interdisciplinary thinking (science‐ and human‐centered) because it can provide public support and government legitimacy for investing in environmental solutions.
Publisher: Springer Science and Business Media LLC
Date: 26-02-2018
Publisher: Elsevier BV
Date: 07-2017
DOI: 10.1016/J.CUB.2017.06.023
Abstract: Accelerating climate change is eroding the functioning and stability of ecosystems by weakening the interactions among species that stabilize biological communities against change [1]. A key challenge to forecasting the future of ecosystems centers on how to extrapolate results from short-term, single-species studies to community-level responses that are mediated by key mechanisms such as competition, resource availability (bottom-up control), and predation (top-down control) [2]. We used CO
Publisher: Springer Science and Business Media LLC
Date: 07-2001
Publisher: Inter-Research Science Center
Date: 27-06-2013
DOI: 10.3354/MEPS10323
Publisher: Wiley
Date: 11-02-2016
DOI: 10.1002/LOM3.10088
Publisher: Springer Science and Business Media LLC
Date: 30-11-2006
Publisher: Elsevier BV
Date: 12-2017
Publisher: Wiley
Date: 13-11-2018
DOI: 10.1002/FEE.1973
No related grants have been discovered for Sean Connell.