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Shuangcheng Li - One of the best experts on this subject based on the ideXlab platform.
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evaluating regional water security through a Freshwater Ecosystem service flow model a case study in beijing tianjian hebei region china
Ecological Indicators, 2017Co-Authors: Delong Li, Shuyao Wu, Ze Liang, Shuangcheng LiAbstract:Abstract Freshwater Ecosystem service is essential to human’s survival and development. Many studies have documented the spatial differences in the supply and demand of Ecosystem services and proposed the concept of Ecosystem services flows. However, few studies characterize Freshwater Ecosystem service flow quantitatively. Therefore, our paper aims to quantify the effects of Freshwater Ecosystem service flow on downstream areas. We developed a Freshwater Ecosystem service flow model and applied it in the Beijing–Tianjin–Hebei (BTH) region, China, for the year of 2000, 2005, and 2010. We assessed the regional water security with an improved Freshwater security index by integrating Freshwater service provision, consumption and flow; and found that most areas of the BTH region (69.2%) were affected by upstream Freshwater flows. The areas achieving water security in the region also expanded to 66.9%, 66.1%, and 71.3%, which were 6.4%, 6.8% and 5.7% increments compared to no-flow situation, in 2000, 2005 and 2010, respectively. Setting quota for human water consumption is suggested to further improve water security. These results highlight the need to fully understand the connections between distant Freshwater Ecosystem service provision and local Freshwater Ecosystem service consumption. This approach may also help managers to choose more sustainable strategies for critical Freshwater resource management across different regions.
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Freshwater Ecosystem service footprint model a model to evaluate regional Freshwater sustainable development a case study in beijing tianjin hebei china
Ecological Indicators, 2014Co-Authors: Zhe Feng, Yan Li, Shuangcheng LiAbstract:Abstract Freshwater is the essential resource element to support and ensure human life and regional sustainable development. On the basis of the concept of Ecosystem service footprint proposed by Burkhard, in this paper, we introduce a new methodological approach that addresses the sustainability and capability of regional Freshwater provision and consumption, which we have coined Freshwater Ecosystem service footprint model (FESF model). The FESF model enhances the accuracy of water provision and consumption calculations and reveals a spatial-pattern of Freshwater Ecosystem service footprint at the watershed scale, overcoming the shortcomings of the traditional water footprint model, which was first introduced by Rees and Wackernagel in 1992. The proposed model is tested in the Beijing–Tianjin–Hebei (BTH) Freshwater supply area in China, where water use restrictions are regularly imposed on the population and economic activities. The results of the physical process and theoretical analysis reveal that FESF model is a reliable and helpful model for researchers to understand the regional Freshwater situation. The average FESF is 0.94 hectare per capita in BTH, with a maximum of 2.52 hectare per capita and a minimum of 0.36 hectare per capita. Approximately 16.8% of the considered region, primarily parts of the mid-northern region and the surrounding eastern and southern low-lying regions, is under high Freshwater resource pressure. In conclusion, this model can be used by researchers and policymakers for promoting sustainable human–ecology interactions.
Alba Esmeralda Zarcoarista - One of the best experts on this subject based on the ideXlab platform.
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spatial heterogeneity of water quality in a highly degraded tropical Freshwater Ecosystem
Environmental Management, 2009Co-Authors: Luis Zambrano, Victoria Contreras, Marisa Mazarihiriart, Alba Esmeralda ZarcoaristaAbstract:Awareness of environmental heterogeneity in Ecosystems is critical for management and conservation. We used the Xochimilco Freshwater system to describe the relationship between heterogeneity and human activities. This tropical aquatic Ecosystem south of Mexico City is comprised of a network of interconnected canals and lakes that are influenced by agricultural and urban activities. Environmental heterogeneity was characterized by spatially extensive surveys within four regions of Xochimilco during rainy and dry seasons over 2 years. These surveys revealed a heterogeneous system that was shallow (1.1 m, SD = 0.4 ), warm (17°C, SD = 2.9), well oxygenated (5.0 mg l−1, SD = 3), turbid (45.7 NTU SD = 26.96), and extremely nutrient-rich (NO3–N = 15.9 mg l−1, SD=13.7; NH4–N = 2.88 mg l−1, SD = 4.24; and PO4–P = 8.3 mg l−1, SD = 2.4). Most of the variables were not significantly different between years, but did differ between seasons, suggesting a dynamic system within a span of a year but with a high resilience over longer periods of time. Maps were produced using interpolations to describe distributions of all variables. There was no correlation between individual variables and land use. Consequently, we searched for relationships using all variables together by generating a combined water quality index. Significant differences in the index were apparent among the four regions. Index values also differed within individual region and individual water bodies (e.g., within canals), indicating that Xochimilco has high local heterogeneity. Using this index on a map helped to relate water quality to human activities and provides a simple and clear tool for managers and policymakers.
Julian D Olden - One of the best experts on this subject based on the ideXlab platform.
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response diversity nonnative species and disassembly rules buffer Freshwater Ecosystem processes from anthropogenic change
Global Change Biology, 2017Co-Authors: Jonathan W Moore, Julian D OldenAbstract:Integrating knowledge of environmental degradation, biodiversity change, and Ecosystem processes across large spatial scales remains a key challenge to illuminating the resilience of Earth's systems. There is now a growing realization that the manner in which communities will respond to anthropogenic impacts will ultimately control the Ecosystem consequences. Here we examine the response of Freshwater fishes and their nutrient excretion - a key Ecosystem process that can control aquatic productivity - to human land development across the contiguous United States. By linking a continental-scale dataset of 533 fish species from 8,100 stream locations with species functional traits, nutrient excretion, and land remote sensing, we present four key findings. First, we provide the first geographic footprint of nutrient excretion by Freshwater fishes across the United States and reveal distinct local- and continental-scale heterogeneity in community excretion rates. Second, fish species exhibited substantial response diversity in their sensitivity to land development; for native species, the more tolerant species were also the species contributing greater Ecosystem function in terms of nutrient excretion. Third, by modeling increased land-use change and resultant shifts in fish community composition, land development is estimated to decrease fish nutrient excretion in the majority (63%) of ecoregions. Fourth, the loss of nutrient excretion would be 28% greater if biodiversity loss was random or 84% greater if there were no non-native species. Thus, Ecosystem processes are sensitive to increased anthropogenic degradation but biotic communities provide multiple pathways for resistance and this resistance varies across space. This article is protected by copyright. All rights reserved.
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Incorporating thermal regimes into environmental flows assessments: modifying dam operations to restore Freshwater Ecosystem integrity
Freshwater Biology, 2010Co-Authors: Julian D Olden, Robert J. NaimanAbstract:SUMMARY 1. Despite escalating conflict over fresh water, recent years have witnessed a growing realisation that human society must modify its behaviour to ensure long-term ecological vitality of riverine Ecosystems. In response, ecologists have been increasingly asked to guide instream flow management by providing ‘environmental flow’ prescriptions for sustaining the ecological integrity of riverine systems. 2. Environmental flows are typically discussed in the context of water releases from dams and water allocation for extraction (such as for urban use or irrigation), where there is general agreement that rivers need to exhibit some resemblance of natural flow variability necessary to support a functioning Ecosystem. Although productive dialogue continues on how best to define environmental flows, these discussions have been focused primarily on water quantity without explicit consideration of many components of water quality, including water temperature – a fundamental ecological variable. 3. Many human activities on the landscape have modified riverine thermal regimes. In particular, many dams have modified thermal regimes by selectively releasing hypolimnetic (cold) or epilimnetic (warm) water from thermally stratified reservoirs to the detriment of entire assemblages of native organisms. Despite the global scope of thermal alteration by dams, the prevention or mitigation of thermal degradation has not entered the conversation when environmental flows are discussed. 4. Here, we propose that a river’s thermal regime is a key, yet poorly acknowledged, component of environmental flows. This study explores the concept of the natural thermal regime, reviews how dam operations modify thermal regimes, and discusses the ecological implications of thermal alteration for Freshwater Ecosystems. We identify five major challenges for incorporating water temperatures into environmental flow assessments, and describe future research opportunities and some alternative approaches for confronting those challenges. 5. We encourage ecologists and water managers to broaden their perspective on environmental flows to include both water quantity and quality with respect to restoring natural thermal regimes. We suggest that scientific research should focus on the comprehensive characterisation of seasonality and variability in stream temperatures, quantification of the temporal and spatial impacts of dam operations on thermal regimes and clearer elucidation of the relative roles of altered flow and temperature in shaping ecological patterns and processes in riverine Ecosystems. Future investigations should also concentrate on using this acquired knowledge to identify the ‘manageable’ components of the thermal regime, and develop optimisation models that evaluate management
Miguel Clavero - One of the best experts on this subject based on the ideXlab platform.
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revisiting ecological integrity 30 years later non native species and the misdiagnosis of Freshwater Ecosystem health
Fish and Fisheries, 2013Co-Authors: Virgilio Hermoso, Miguel ClaveroAbstract:Assessing the ecological integrity of Freshwater Ecosystems has become a priority to protect the threatened biodiversity they hold and secure future accessibility to the services they provide. Some of the most widespread applications of biological indicators are fish-based indices. These have mostly mirrored the approach proposed by Karr 30 years ago (Index of Biotic Integrity; IBI), based on the comparison of observed and expected composition and structure of local fish assemblages in the absence of major perturbations, using the so-called reference condition approach. Despite the notable success of the implementation of fish-based indices, most of them overlook non-native species as a source of Ecosystem degradation, and evaluations are focused on the physico-chemical condition of Freshwater Ecosystems and their effects on Freshwater biodiversity. Almost 90% of 83 reviewed IBIs did not consider non-native species when defining reference conditions. Most IBIs used non-native species in conjunction with native ones to construct the metrics that conform to the index. The response of the IBI to the effect of non-native species has hardly ever been tested. When developing and evaluating IBIs, attention was mostly directed to ensuring the correct response of the index to physico-chemical parameters, which could otherwise be characterized more effectively using alternative methods. Current application of IBIs entails a misuse of biological indicators by overlooking some types of degradation that cannot be otherwise evaluated by traditional methods. This constrains the capacity to adequately respond to one of the most challenging and common threats to the conservation of Freshwater fish diversity.
M M Fisher - One of the best experts on this subject based on the ideXlab platform.
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modeling of the spatial variability of biogeochemical soil properties in a Freshwater Ecosystem
Ecological Modelling, 2007Co-Authors: Sabine Grunwald, Krishna R Reddy, J P Prenger, M M FisherAbstract:Ecosystem services are dependent on the geospatial composition, structure, and function of an Ecosystem. Our goal was to gain a better understanding of the variability of biogeochemical soil properties along gradients of impacted and unimpacted zones within a subtropical wetland in Florida. Our objectives were to (i) characterize the spatial variability and distribution of soil total phosphorus (TP), (ii) identify the magnitude and scale at which multiple biogeochemical soil properties account for variability within the Ecosystem, and (iii) map the distribution of this variability. We collected soil samples (0–10 cm) at 266 sites within the Blue Cypress Marsh Conservation Area (4900 ha) in Florida that were analyzed for 18 different biogeochemical properties. Conditional sequential Gaussian simulation and principal component analysis was used to identify three major groups of behavior: (i) labile, fast response properties with fine-scale spatial autocorrelation; (ii) stable, slow response properties with regional spatial autocorrelation; (iii) properties showing intermediate response. The uncertainty of the spatial variability measures was described using small and large realizations as well as standard deviation maps. The first principal component (PC) [group (i)] contributed with 33.91%, the second PC [group (ii)] with 15.93%, and the third PC [group (iii)] with 11.32% to the total variance. Properties that explain much of the underlying variability in a wetland are expected to be more sensitive to change than others that show more homogeneous patterns. More research is needed to reveal geospatial interrelationships of biogeochemical properties and their underlying spatial structure in aquatic Ecosystems.
