ORCID Profile
0000-0002-6558-7477
Current Organisation
University of Zurich
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Publisher: Elsevier BV
Date: 11-2008
Publisher: Springer Science and Business Media LLC
Date: 22-02-2021
DOI: 10.1038/S43247-021-00112-Y
Abstract: As planetary boundaries loom, there is an urgent need to develop sustainable equilibriums between societies and the resources they consume, thereby avoiding regime shifts to undesired states. Transient system trajectories to a stable state may differ substantially, posing significant challenges to distinguishing sustainable from unsustainable trajectories. We use stylized models to show how feedbacks between anthropogenic harvest regimes and resource availability drive transient dynamics. We show how substantial time lags may occur between interventions and social-ecological outcomes, and that sudden system collapses need not be linked to recent environmental changes. Historical reconstructions of island state populations show a variety of transient dynamics that closely corresponds to model expectations based on island differences in productivity and harvesting regime. We conclude that vulnerable social-ecological systems may persist when the population:resource ratio remains within a viable range of intermediate (rather than small) values, which implies that averting environmental crises may require counter-intuitive measures.
Publisher: Elsevier BV
Date: 02-2011
Publisher: Cambridge University Press (CUP)
Date: 07-2009
Abstract: Invasive aquatic weeds negatively affect bio ersity, fluvial dynamics, water quality, and water storage and conveyance for a variety of human resource demands. In California's Sacramento–San Joaquin River Delta, one submersed species—Brazilian egeria—and one floating species—waterhyacinth—are actively managed to maintain navigable waterways. We monitored the spatial and temporal dynamics of these species and their communities in the Sacramento-San Joaquin River Delta using airborne hyperspectral data and assessed the effect of herbicide treatments used to manage these species from 2003 to 2007. Each year, submersed aquatic plant species occupied about 12% of the surface area of the Delta in early summer and floating invasive plant species occupied 2 to 3%. Since 2003, the coverage of submersed aquatic plants expanded about 500 ha, whereas the coverage of waterhyacinth was reduced. Although local treatments have reduced the coverage of submersed aquatic plants, Delta-wide cover has not been significantly reduced. Locally, multiyear treatments could decrease submersed aquatic plants spread, given that no residual plants outside the treated area were present. In contrast, the spread of waterhyacinth either has been constant or has decreased over time. These results show that (1) the objectives of the Egeria densa Control Program (EDCP) have been hindered until 2007 by restrictions imposed on the timing of herbicide applications (2) submersed aquatic plants appeared to function as ecosystem engineers by enabling spread to adjacent areas typically subject to scouring action (3) repeated herbicide treatment of waterhyacinth has resulted in control of the spread of this species, which also appears to have facilitated the spread of waterprimrose and floating pennywort. These results suggest that management of the Delta aquatic macrophytes may benefit by an ecosystem-level implementation of an Integrated Delta Vegetation Management and Monitoring Program, rather than targeting only two problematic species.
Publisher: Wiley
Date: 03-05-2021
Abstract: Ecosystem heterogeneity has been widely recognized as a key ecological indicator of several ecological functions, ersity patterns and change, metapopulation dynamics, population connectivity or gene flow. In this paper, we present a new R package— raster —to calculate heterogeneity indices based on remotely sensed data. We also provide an ecological application at the landscape scale and demonstrate its power in revealing potentially hidden heterogeneity patterns. The raster package allows calculating multiple indices, robustly rooted in Information Theory, and based on reproducible open‐source algorithms.
Publisher: Wiley
Date: 09-2016
DOI: 10.1890/15-0615
Abstract: Processes of spread and patterns of persistence of invasive species affect species and communities in the new environment. Predicting future rates of spread is of great interest for timely management decisions, but this depends on models that rely on understanding the processes of invasion and historic observations of spread and persistence. Unfortunately, the rates of spread and patterns of persistence are difficult to model or directly observe, especially when multiple rates of spread and erse persistence patterns may be co-occurring over the geographic distribution of the invaded ecosystem. Remote sensing systematically acquires data over large areas at fine spatial and spectral resolutions over multiple time periods that can be used to quantify spread processes and persistence patterns. We used airborne imaging spectroscopy data acquired once a year for 5 years from 2004 to 2008 to map an invaded submerged aquatic vegetation (SAV) community across 2220 km
Publisher: Frontiers Media SA
Date: 11-08-2022
DOI: 10.3389/FENVS.2022.918085
Abstract: Water, energy, and food are all essential components of human societies. Collectively, their respective resource systems are interconnected in what is called the “nexus”. There is growing consensus that a holistic understanding of the interdependencies and trade-offs between these sectors and other related systems is critical to solving many of the global challenges they present. While nexus research has grown exponentially since 2011, there is no unified, overarching approach, and the implementation of concepts remains h ered by the lack of clear case studies. Here, we present the results of a collaborative thought exercise involving 75 scientists and summarize them into 10 key recommendations covering: the most critical nexus issues of today, emerging themes, and where future efforts should be directed. We conclude that a nexus community of practice to promote open communication among researchers, to maintain and share standardized datasets, and to develop applied case studies will facilitate transparent comparisons of models and encourage the adoption of nexus approaches in practice.
Publisher: Wiley
Date: 29-11-2011
DOI: 10.1111/J.1469-8137.2011.03955.X
Abstract: • Nonnative species may change ecosystem functionality at the expense of native species. Here, we examine the similarity of functional traits of native and nonnative submersed aquatic plants (SAP) in an aquatic ecosystem. • We used field and airborne imaging spectroscopy and isotope ratios of SAP species in the Sacramento-San Joaquin Delta, California (USA) to assess species identification, chlorophyll (Chl) concentration, and differences in photosynthetic efficiency. • Spectral separability between species occurs primarily in the visible and near-infrared spectral regions, which is associated with morphological and physiological differences. Nonnatives had significantly higher Chl, carotene, and anthocyanin concentrations than natives and had significantly higher photochemical reflectance index (PRI) and δ(13) C values. • Results show nonnative SAPs are functionally dissimilar to native SAPs, having wider leaf blades and greater leaf area, dense and evenly distributed vertical canopies, and higher pigment concentrations. Results suggest that nonnatives also use a facultative C(4) -like photosynthetic pathway, allowing efficient photosynthesis in high-light and low-light environments. Differences in plant functionality indicate that nonnative SAPs have a competitive advantage over native SAPs as a result of growth form and greater light-use efficiency that promotes growth under different light conditions, traits affecting system-wide species distributions and community composition.
Publisher: Springer International Publishing
Date: 2020
DOI: 10.1007/978-3-030-33157-3_12
Abstract: The spread of invasive alien species (IAS) is recognized as the most severe threat to bio ersity outside of climate change and anthropogenic habitat destruction. IAS negatively impact ecosystems, local economies, and residents. They are especially problematic because once established, they give rise to positive feedbacks, increasing the likelihood of further invasions and spread. The integration of remote sensing (RS) to the study of invasion, in addition to contributing to our understanding of invasion processes and impacts to bio ersity, has enabled managers to monitor invasions and predict the spread of IAS, thus supporting bio ersity conservation and management action. This chapter focuses on RS capabilities to detect and monitor invasive plant species across terrestrial, riparian, aquatic, and human-modified ecosystems. All of these environments have unique species assemblages and their own optimal methodology for effective detection and mapping, which we discuss in detail.
Publisher: Wiley
Date: 04-03-2013
Publisher: Oekom Publishers GmbH
Date: 20-10-2022
DOI: 10.14512/GAIA.31.3.3
Abstract: Games as a didactic tool (e. g., puzzles) are gaining recognition in environmental education to promote skill development, but also to develop a specific understanding of the natural world. However, a children’s puzzle containing representations of nature may unwillingly lead to “misconceptions” of bio ersity themes and processes, and an over-simplification of the relationship between people and nature. To solve this problem, positive connotations of bio ersity may prompt a conceptual change to a more nuanced, multifaceted conception of bio ersity.
Publisher: Wiley
Date: 26-02-2016
Publisher: Springer Science and Business Media LLC
Date: 05-10-2011
Location: United States of America
No related grants have been discovered for Maria Joao Santos.