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0000-0003-2763-2692
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Human Geography | Landscape Ecology | Environmental Science and Management | Ecological Applications | Social and Cultural Geography | Conservation and Biodiversity | Marine And Estuarine Ecology (Incl. Marine Ichthyology) | Environment Policy | Conservation And Biodiversity | Natural Resource Management | Urban And Regional Studies
Remnant vegetation and protected conservation areas | Understanding legal processes | Institutional Arrangements for Environmental Protection | Land Stewardship | Living resources (incl. impacts of fishing on non-target species) | Integrated (ecosystem) assessment and management | Remnant Vegetation and Protected Conservation Areas in Farmland, Arable Cropland and Permanent Cropland Environments | Native vegetation | Marine protected areas | Integrated (ecosystem) assessment and management | Environmental and resource evaluation not elsewhere classified |
Publisher: Wiley
Date: 30-10-2008
Publisher: Springer Science and Business Media LLC
Date: 06-1986
DOI: 10.1007/BF00039906
Publisher: Elsevier BV
Date: 05-2006
Publisher: Wiley
Date: 27-12-2022
DOI: 10.1111/EMR.12541
Abstract: The role of recreational fishers forming paths (routes of concentrated passage characterised by short vegetation or ground indentation) as they gain access to wilderness waterbodies has not been well documented in Australia. Recreational use for trout and tournament fly fishing has increased in the Central Plateau of Tasmania therefore, it is important to determine the human contribution to path formation and its potential consequences for bio ersity conservation in this area of high conservation value. We predicted that paths parallel to waterbodies experienced more human traffic than orthogonal paths. Across 36 sites at different distances from roads, a parallel and orthogonal path to lakeshore were s led using eight, 1 × 1 m quadrats randomly located along each path within a 10 × 10‐m plot. Recorded for each quadrat were the path widths, height difference between centre of paths and adjacent vegetation (path depth), vegetation types on and adjacent to paths, Bennetts Wallaby ( Notamacropus rufogriseus ) and Wombat ( Vombatus ursinus ) faecal numbers. General linear models indicated that path width was greater on parallel than orthogonal paths and declined with distance from roads. Path depth, however, was not affected by distance from roads but was shallower than orthogonal paths. Separate models used to test the potential effects of edge vegetation type, or the covariates Wallaby and Wombat scats did not have significant effects on‐path variables. Paths encircling or orthogonal to Central Plateau lakes appear different floristically to adjacent vegetation communities, nonetheless. Heath and tussock grassland were largely absent from paths, whereas grassland and herbfield communities were infrequently observed off paths. Herbfield and grassland are rarer communities than heath and tussock grassland, which, in the context of a lack of exposure to erosion, suggests a conservation benefit of paths at present usage levels. The human contribution to parallel path conditions is likely to be high, given the results from the study, so monitoring of change is desirable, especially if predicted increasing human activity eventuates in this area.
Publisher: Elsevier BV
Date: 09-2015
DOI: 10.1016/J.MARPOLBUL.2015.06.049
Abstract: Intensive fish culture in open sea pens delivers large amounts of nutrients to coastal environments. Relative to particulate waste impacts, the ecological impacts of dissolved wastes are poorly known despite their potential to substantially affect nutrient-assimilating components of surrounding ecosystems. Broad-scale enrichment effects of salmonid farms on Tasmanian reef communities were assessed by comparing macroalgal cover at four fixed distances from active fish farm leases across 44 sites. Macroalgal assemblages differed significantly between sites immediately adjacent (100m) to fish farms and reference sites at 5km distance, while sites at 400m and 1km exhibited intermediate characteristics. Epiphyte cover varied consistently with fish farm impacts in both sheltered and exposed locations. The green algae Chaetomorpha spp. predominated near fish farms at swell-exposed sites, whereas filamentous green algae showed elevated densities near sheltered farms. Cover of canopy-forming perennial algae appeared unaffected by fish farm impacts.
Publisher: Elsevier BV
Date: 2015
Publisher: Wiley
Date: 17-01-2023
Abstract: Large wild areas are important for both nature conservation and nature‐based recreation. Information on the reciprocal relationships between recreators and the environments in which they recreate can help both conservation and recreation management. We considered motivations, perceptions, environmental concerns, and social concerns among flyfishers who recreate within the Tasmanian Wilderness World Heritage Area on the Central Plateau of Tasmania, Australia. Using semi‐structured interviews with 27 participants, we established that they were motivated by a love of nature, desire for experience, escapism, connection, and challenge. On the basis of motivations and attitudes, we discriminated four groups of flyfishers: “social” (those who fish with friends), “trophy” (lone fishers who are goal‐oriented), “outdoor enthusiast” (those who enjoy the outdoor experience, fishing optional), and “hunter‐gatherer” (those prepared to travel long distances for catch). Nonetheless, all groups perceived environmental and social problems related to fishing and visitation behaviours, from littering to climate change. Fishers perceived environmental problems included identifying exotic weeds and pests but did not specifically include trout as a pest, despite their exotic status and adverse effects on native ecosystems. However, flyfishers were aware of most of their impacts and were willing to help mitigate them. Such insight is significant for geographers and those in associated disciplines and professions seeking to manage wild protected areas.
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/BT09131
Abstract: Little is known of the interactive effects of fire and grazing on cryptogam species and assemblages. These effects were observed for bryophyte and lichen species in Tasmanian tussock grassland and hummock sedgeland several months after experimental burning and fencing. A factorial design was used on 40 randomly located and treated pairs of 1 m × 1 m quadrats in each of the vegetation types. In total, 24 cryptogam taxa were found, with grassland having a greater taxon richness, as well as higher total cryptogam cover and a different species composition, to the hummock sedgeland. There was greater cryptogam cover in the burned quadrats than the unburned quadrats in the grassland. However, only bryophytes had different species composition between burned and unburned quadrats. There was a small but significant difference in richness in hummock sedgeland, with burned being richer than unburned. Three species were more abundant in the burned than in the unburned treatments in the grassland, whereas no species responded to treatment in the sedgeland and no species responded to grazing. The fact that no species or assemblage of species was significantly reduced in cover by the burns testifies to a high degree of cryptogam resilience to this disturbance. The total lack of negative grazing effects suggests cryptogams are not a major source of sustenance for the local vertebrate herbivores. These conclusions differ from those made elsewhere in the world.
Publisher: Wiley
Date: 10-1986
Publisher: Wiley
Date: 24-11-2010
DOI: 10.1111/J.1523-1739.2009.01378.X
Abstract: Our knowledge of cryptogam taxonomy and species distributions is currently too poor to directly plan for their conservation. We used inventory data from four distinct vegetation types, near Hobart Tasmania, to address the proposition that vegetation type, vascular plant taxon composition, and environmental variables can act as surrogates for mosses and macrofungi in reservation planning. The four vegetation types proved distinct in their taxon composition for all macrofungi, mosses, and vascular plants. We tested the strength of the relationships between the composition of cryptogam taxonomic groups and vascular plant composition and between the environmental variables and canopy cover. Taxon composition of woody vascular plants and vascular plants was the best predictor of the taxon composition of mosses and macrofungi. Combinations of environmental variables and canopy cover were also strong predictors of the taxon composition of mosses and macrofungi. We used an optimization routine for vascular plant taxa and woody plant species and determined the representation of cryptogam taxa in these selections. We identified sites with approximately 10% and 30% of the greatest proportions of vascular plants and woody vascular plants and calculated representation of mosses and macrofungi at these sites. We compared the results of these site selections with random site selections and random selections stratified by vegetation type. Random selection of sites by vegetation type generally captured more cryptogams than site selection by vascular plants at the 10% level. Vascular plant and woody plant taxon composition, vegetation type, and environmental and structural characteristics, all showed promise as surrogates for capturing common cryptogams in reserve systems.
Publisher: Wiley
Date: 19-08-2010
Publisher: Informa UK Limited
Date: 2012
Publisher: Elsevier BV
Date: 10-2014
Publisher: CSIRO Publishing
Date: 1986
DOI: 10.1071/BT9860081
Abstract: Field and pot experiments were designed to test the relative roles of allelopathy, competition for moisture and competition for nutrients in the suppression and growth of Eucalyptus delegatensis. In pot experiments litter cover was associated with slightly slower growth rates than in other treatments. A fertilization treatment was associated with increased growth rates in both trenched and untrenched situations in a field experiment, but the effect of fertilization was subdued in comparison with the effects of trenching or of total tree removal in the clear-felling treatment. Saplings and seedlings in the forest were under significantly greater moisture stress, as indicated by xylem pressure potential and stomata1 resistance, than those growing in the adjacent clear-felled areas. Surface soils in clear-felled areas had moisture contents above the level which caused seedling stress while surface soils within the forest were often below this level. These findings suggest that adult trees suppress seedling and sapling regrowth largely through their effect on soil moisture. However, another form of seedling growth suppression also occurs in the open as a result of frost damage.
Publisher: Elsevier BV
Date: 06-2008
Publisher: University of Chicago Press
Date: 02-2011
DOI: 10.1086/657280
Publisher: Wiley
Date: 26-05-2004
Publisher: Wiley
Date: 09-2014
Publisher: Wiley
Date: 30-03-2016
DOI: 10.1111/EMR.12204
Publisher: CSIRO Publishing
Date: 1992
DOI: 10.1071/BT9920311
Abstract: In the savannah of Melville Island, Northern Temtory floristic variation relates strongly to both soil moisture regimes at different depths in the profile and chemical edaphic conditions. While some elements of variation in vegetation structure and overstorey species composition have clear edaphic relationships, many common tree species could be found as important overstorey components in a range of edaphic situations. The interaction of stochastic disturbance events and phenological condition may explain this deviation from environmental determinism.
Publisher: Elsevier BV
Date: 12-2011
Publisher: CSIRO Publishing
Date: 1986
DOI: 10.1071/BT9860063
Abstract: In the dry uneven-aged eucalypt forests of central Tasmania the establishment of seedlings of Eucalyptus delegatensis requires a mitigation of the competition provided by the understorey, regeneration being observed to follow both fire and cultivation. Most of the adult trees of E. delegatensis survive even severe fires, although there can be considerable later mortality associated with mechanical failure of the base of the trunk. E. delegatensis dry forest usually has a distinctive sapling layer. Fire kills most of these saplings, the mortality rate being inversely related to their height and bark thickness.
Publisher: Wiley
Date: 28-09-2005
Publisher: Wiley
Date: 05-2019
DOI: 10.1002/AQC.3085
Publisher: Wiley
Date: 11-12-2009
DOI: 10.1111/J.1365-2656.2009.01609.X
Abstract: 1. The general importance of metacommunity and metapopulation theories is poorly understood because few studies have examined responses of the suite of species that occupy the same fragmented landscape. In this study, we examined the importance of spatial ecological theories using a large-scale, naturally fragmented landscape. 2. We measured the occurrence and abundance of 44 common beetle species in 31 natural rainforest fragments in Tasmania, Australia. We tested for an effect on beetle distribution of geographic variables (patch area, patch isolation and amount of surrounding habitat) and of environmental variables based on plant species, after first accounting for spatial autocorrelation using principal coordinates of neighbour matrices. The environmental variables described a productivity gradient and a post-fire succession from eucalypt-dominated forest to late-successional rainforest. 3. Few species had distributions consistent with a metapopulation. However, the amount of surrounding habitat and patch isolation influenced the occurrence or abundance of 30% of beetle species, implying that dispersal into or out of patches was an important process. 4. Three species showed a distribution that could arise by interactions with dominant competitors or predators with higher occurrence in small patches. 5. Environmental effects were more commonly observed than spatial effects. Twenty-three per cent of species showed evidence of habitat-driven, deterministic metapopulations. Furthermore, almost half of the species were influenced by the plant succession or productivity gradient, including effects at the within-patch, patch and regional scales. The beetle succession involved an increase in the frequency of many species, and the addition of new species, with little evidence of species turnover. Niche-related ecological theory such as the species-sorting metacommunity theory was therefore the most broadly applicable concept. 6. We conclude that classic and source-sink metapopulations are probably rare in this large-scale, naturally fragmented system, although dispersal processes like those occurring in metapopulations may have a substantial influence on community composition. However, deterministic processes (niche specialisation, species-sorting metacommunities and deterministic metapopulations) drive the occurrence or frequency of the majority of species. We urge further research into the prevalence of spatial ecological processes in large-scale natural ecosystems to expand our understanding of the processes that may be important in nature.
Publisher: Informa UK Limited
Date: 06-08-2010
Publisher: Elsevier BV
Date: 06-2017
Publisher: American Bryological and Lichenological Society
Date: 12-2011
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/BT11206
Abstract: Coastal saltmarshes are reputed to be one of the most vulnerable communities to global warming, with widespread evidence of retreat and movement of lower marsh vegetation into areas previously occupied by upper marsh vegetation in response to rising sea levels, and potential changes in community composition from changes in rainfall, temperature and wind. We undertook an investigation of decades scale change in the distributions of saltmarsh communities defined by dominant species, using historic vegetation maps, remote sensing imagery and extensive field data collection. Our study area in south-eastern Tasmania has suffered a marked increase in temperatures and wind speeds and a marked decrease in rainfall since 1975, with sea level rising at a rate of 0.8 mm per annum. We therefore tested the hypothesis that these changes would result in a shift in saltmarsh community composition towards more salt- and inundation-tolerant communities and salt scalds. Eighteen percent of the 1975 marsh was lost to direct human modification and a net 4% was lost to coastal retreat. One large marsh was cut off from the sea then burned, then reconnected with the sea. The vegetation change between 1975 and 2009 in other parts of the saltmarshes occurred in 21% of their 1975 area. Most of the community transitions were consistent with increasing aridity. Thus, our results indicate that global warming has already caused marked changes in community composition in saltmarsh in Tasmania.
Publisher: CSIRO Publishing
Date: 2010
DOI: 10.1071/BT10138
Abstract: Fire appears to be a rare event in alpine vegetation, suggesting that its effects might be more persistent than in most lowland vegetation types. However, it has been suggested that the Australian alpine biota is resilient to infrequent large fires. This paper describes decades-scale vegetation and soil change after fire in paired plots over fire boundaries in Tasmanian alpine coniferous heath. The effect of fire on soils persisted for decades. Recovery of vegetation was extremely slow by global standards, with delayed reinvasion of previously dominant species. There was low cover of the most fire-sensitive species 43–69 years after fire and much bare ground still evident, with the rate of revegetation declining through time. Gymnosperm shrubs increased at the expense of angiosperms in the unburned plots in the same period and cryptogams declined in both burned and unburned plots. These results suggest that the Tasmanian alpine flora cannot be characterised as resilient to infrequent large fire, although most species survive its incidence. The many centuries that it appears are necessary for coniferous heath to recover to its pre-burn state suggest that fires caused by increased ignitions from lightning and arsonists are the major issue for conservation of the vegetation type.
Publisher: University of Chicago Press
Date: 02-2010
DOI: 10.1086/648990
Publisher: Wiley
Date: 12-1987
Publisher: CSIRO Publishing
Date: 1984
DOI: 10.1071/BT9840613
Abstract: Observations were made across 11-40-year-old fire boundaries in Tasmanian alpine areas of varying macroenvironment and flora. Organic matter and total nitrogen in the surface soil were significantly less where the vegetation had been recently burned. There were no significant differences between recently burned and recently unburned plots in contents of phosphorus, potassium, calcium or sodium or in pH. The burned plots contained few or no gymnosperms or deciduous shrubs, the most frequent dominants of the unburned vegetation. Most other shrubs were markedly less important in the burned than in the unburned plots, although most species of bolster form were little affected by fire, and some composite shrubs were most abundant on the burned plots. Most herbaceous species had equal or greater cover on the burned plots than on the unburned plots. The burned vegetation of the eastern mountains appeared to regenerate more quickly than that of the more oligotrophic western mountains.
Publisher: Wiley
Date: 10-11-2015
DOI: 10.1111/GEB.12389
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/BT16179
Abstract: Alpine plant species are considered to have a precarious near future in a warming world, especially where endemic on mountains without a nival zone. We investigated how and why snow patch vegetation and snow incidence varied over recent decades in Tasmania, Australia. Landsat images between 1983 and 2013 were used to calculate the proportion of clear days with snow visible on Mt Field. We compared average annual snow incidence on 74 Tasmanian alpine mountains for 1983–1996 with that for 1997–2013 using the small subset of Landsat runs in which most of Tasmania was clear of cloud. We related the temporal data from Mt Field to Tasmanian climatic data and climate indices to determine the predictors of change. We recorded plant species and life form cover from quadrats in transects through a snow patch on Mt Field in 1983, 2001 and 2014, and mapped decadal scale changes in boundaries and shrub cover at five other snow patches across the extent of the Tasmanian alpine areas from aerial photographs. The incidence of snow fluctuated between 1983 and 2013 at Mt Field with no overall trend. Snow incidence was less on lower elevation alpine mountains in the period 1997–2013 than in the period 1983–1996, but showed a weak opposite trend on mountains higher than 1350 m. The contrast in trends may be a consequence of the effect on lapse rates of stronger frontal winds associated with a steepening of latitudinal pressure gradients. At Mt Field, bare ground decreased, cover of cushion plants and tall shrubs increased and obligate snow patch species were persistent. The trends we observed in both vegetation and snow incidence differ markedly from those observed on mainland Australia. The increase in shrub cover and decrease in bare ground on Mt Field were unexpected, given the constancy in incidence of snow. These results may relate to ongoing recovery from a fire in the 1960s, as the shrub species that have increased are fire-sensitive, obligate seeders and there has been no indication of warming since 1983 in the climatic record for western Tasmania. There is a possibility that some Tasmanian alpine areas might act as long-term refugia from general warming.
Publisher: CSIRO Publishing
Date: 2006
DOI: 10.1071/BT04138
Abstract: The species richness and species composition of bryophytes (mosses and liverworts) was recorded at 33 sites in Tasmanian old growth mixed eucalypt forest. A total of 202 bryophyte taxa were recorded, consisting of 115 liverworts and 87 mosses. This constitutes approximately one third of the total bryophyte flora for Tasmania. Mean liverwort species richness per site was higher than moss species richness. Latitude was found to be a positive predictor in all multiple regression models of bryophyte, moss and liverwort species richness. Mean annual temperature and rainfall of the driest month were positive predictors for bryophyte and liverwort species richness. Basal area of the treefern Dicksonia antarctica Labill. was a negative predictor of liverwort species richness. Latitude, variables relating to moisture, mean annual temperature, rainfall of the driest month and basal area of Dicksonia antarctica were the most significant components in predicting variation in bryophyte, moss and liverwort species composition. There were few relationships between the variables of canopy cover and soil nutrients and bryophyte species richness and composition. Substrate variables were found to be important components in predicting variation in moss and bryophyte species composition.
Publisher: Elsevier BV
Date: 06-2018
DOI: 10.1016/J.ENVPOL.2018.02.061
Abstract: Macroalgal beds provide important habitat structure and support primary production for rocky reef communities, but are increasingly degraded as a result of human pressures. Various sources of pollution can have both direct and interactive effects on stressed ecosystems. In particular, interactions involving invertebrate grazers could potentially weaken or strengthen the overall impact of pollution on macroalgal beds. Using a paired impact-control experimental design, we tested the effects of multiple pollution sources (fish farms, marinas, sewerage, and stormwater) on translocated and locally established algal assemblages, while also considering the influence of invertebrate grazers. Marinas directly affected algal assemblages and also reduced densities of hipods and other invertebrate mesograzers. Fish farms and sewerage outfalls tended to directly increase local establishment of foliose and leathery algae without any indication of changes in herbivory. Overall, pollution impacts on algae did not appear to be strongly mediated by changes in grazer abundance. Instead, mesograzer abundance was closely linked to availability of more complex algal forms, with populations likely to decline concurrently with loss of complex algal habitats. Macrograzers, such as sea urchins, showed no signs of a negative impact from any pollution source hence, the influence of this group on algal dynamics is probably persistent and independent of moderate pollution levels, potentially adding to the direct impacts of pollution on algal beds in urbanised environments.
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/BT16094
Abstract: The term ‘snow patch’ indicates an area in an alpine zone with distinct vegetation because snow persists there longer than in the surrounding areas. Snow patches are a well known rare and threatened ecosystem on mainland Australia, but little is known of their distribution and vegetation in Tasmania. We describe, and determine the environmental relationships of, snow patches and their vegetation in Tasmania. There are 119 snow patches in Tasmania, covering 86 ha in toto, 43 of which have some fjaeldmark vegetation and the rest of which have a complete vegetation cover. Snow patches are confined to the taller, more continental mountains where they occur on north-east- to east-facing slopes, with the surrounding alpine vegetation usually being free of persistent snow. Their considerable floristic and structural variability relates to substrate and climate. Within Tasmania, several species are largely restricted to snow patches. The high degree of Tasmanian endemism in the snow-patch vegetation makes it distinct from the snow-patch vegetation of mainland Australia. The Tasmanian snow patches are also distinct in their environmental conditions. In Tasmania, snow does not usually persist over the winter outside the 119 snow patches. There are five floristic communities in these patches, all being distinct from those in mainland Australian snow patches. The Tasmanian snow patches merit listing as a threatened ecosystem on the basis of their distinctiveness and restricted extent.
Publisher: CSIRO Publishing
Date: 1987
DOI: 10.1071/BT9870601
Abstract: The relative impacts of clearfelling followed by slash-burning, clearfelling, and no treatment were monitored for 2 years in two major types of eucalypt forest in south-eastern Tasmania. Rates of change in species cover were significantly greater in the burned area than in both the clearfell and control areas. More than half the species for which suitable data were available increased most in the burned area and least in the control. More higher plant taxa were present in the permanent burned plots 4 months after the burn than before the burn. By the last 8 months of recording, new taxa were invading at a rate of only 0.1 per month. Composites and shrubs constituted most of the late invaders. The behaviour of ersity measures was largely a function of the behaviour of a few of the taxa. Fire intensity, as measured by degree of soil baking, had a pronounced influence on species composition and cover. The species composition of aerially sown seed had little influence on the species composition of the eucalypt regeneration, with species not sown by the Forestry Commission recovering vegetatively, and much of the sown seed not resulting in seedling establishment. The clearfelling and burning, and clearfelling treatments did not result in the loss of any native species but there was substantial invasion by introduced herbs. However, lack of substantial impact in the short term does not guarantee the same in the long term.
Publisher: Informa UK Limited
Date: 2008
Publisher: Springer Science and Business Media LLC
Date: 30-11-2014
Publisher: CSIRO Publishing
Date: 1992
DOI: 10.1071/BT9920123
Abstract: Downslope boundaries of forest with grassland and grassy woodland occur over a wide altitudinal range in central Tasmania. Three sites were selected for study of the causes of these boundaries at low, medium and high elevations. The open vegetation was generally associated with moister and less rocky soils and more subdued topography than the adjacent forest. Frost incidence and intensity, soil moisture and waterlogging varied markedly among the three open areas. Planted tree seedlings survived 4 years in the open at all sites, and seedlings established in the open both naturally, and after sowing, where grass competition was reduced by herbicide application, digging or root competition from adult eucalypts. Grazing had no detectable effect on seedling establishment. A pot experiment demonstrated a suppressive effect of native grass swards on both seedling establishment and growth, this effect being largely independent of available moisture and nutrients. While frost, waterlogging, fire and drought may play a role in inhibiting eucalypt establishment and increasing eucalypt mortality at some or all of the sites, the dense grass swards found in all the open areas are considered to be the most likely primary agent of tree exclusion.
Publisher: Springer Science and Business Media LLC
Date: 14-02-2022
Publisher: Springer Science and Business Media LLC
Date: 13-11-2013
DOI: 10.1038/SREP03188
Publisher: Oxford University Press (OUP)
Date: 02-2013
DOI: 10.1603/EN12322
Publisher: CSIRO Publishing
Date: 1986
DOI: 10.1071/BT9860073
Abstract: Seedling and sapling regrowth occupies gaps and includes part of the understorey in the multiaged Eucalyptus delegatensis dry forests of central Tasmania. This regrowth is even-aged for any particular area. Variation in sapling height is symmetrical across east to west sections of gaps, 20-50 m diam., but asymmetrical in the north to south sections, where the tallest seedlings are found to the south. Density, height, diameter and wet weight of E. delegatensis regrowth are highly positively correlated with the distance to the nearest tree but are only related to solar radiation in the gaps. Concentrations of most major plant nutrients in the surface soil, and soil moisture-holding capacity, have no strong relationship with the various growth measures. Thus, adult trees suppress sapling growth independent of incident solar radiation, while sapling growth outside the influence of adult trees increases with increasing incident solar radiation.
Publisher: MDPI AG
Date: 16-09-2020
DOI: 10.3390/RS12183017
Abstract: Urban trees provide social, economic, environmental and ecosystem services benefits that improve the liveability of cities and contribute to in idual and community wellbeing. There is thus a need for effective mapping, monitoring and maintenance of urban trees. Remote sensing technologies can effectively map and monitor urban tree coverage and changes over time as an efficient and low-cost alternative to field-based measurements, which are time consuming and costly. Automatic extraction of urban land cover features with high accuracy is a challenging task, and it demands object based artificial intelligence workflows for efficiency and thematic accuracy. The aim of this research is to effectively map urban tree cover changes and model the relationship of such changes with socioeconomic variables. The object-based convolutional neural network (CNN) method is illustrated by mapping urban tree cover changes between 2005 and 2015/16 using satellite, Google Earth imageries and Light Detection and Ranging (LiDAR) datasets. The training s le for CNN model was generated by Object Based Image Analysis (OBIA) using thresholds in a Canopy Height Model (CHM) and the Normalised Difference Vegetation Index (NDVI). The tree heatmap produced from the CNN model was further refined using OBIA. Tree cover loss, gain and persistence was extracted, and multiple regression analysis was applied to model the relationship with socioeconomic variables. The overall accuracy and kappa coefficient of tree cover extraction was 96% and 0.77 for 2005 images and 98% and 0.93 for 2015/16 images, indicating that the object-based CNN technique can be effectively implemented for urban tree coverage mapping and monitoring. There was a decline in tree coverage in all suburbs. Mean parcel size and median household income were significantly related to tree cover loss (R2 = 58.5%). Tree cover gain and persistence had positive relationship with tertiary education, parcel size and ownership change (gain: R2 = 67.8% and persistence: R2 = 75.3%). The research findings demonstrated that remote sensing data with intelligent processing can contribute to the development of policy input for management of tree coverage in cities.
No related organisations have been discovered for James Kirkpatrick.
Start Date: 03-2006
End Date: 12-2009
Amount: $276,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 05-2018
End Date: 12-2023
Amount: $338,609.00
Funder: Australian Research Council
View Funded ActivityStart Date: 05-2007
End Date: 06-2010
Amount: $345,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 01-2009
End Date: 01-2012
Amount: $130,000.00
Funder: Australian Research Council
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