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731.
A supportive attitude of residents towards protected areas is crucial for successful implementation and management, particularly in densely populated regions such as Central Europe. While previous studies have revealed that emotional and cultural drivers, as well as information level and group membership, can influence attitudes towards protected areas, the effect of place-attachment dimensions remains unclear. A postal survey among local residents (N = 460) explored factors influencing attitudes towards the Lungau (-Nockberge) Biosphere Reserve in Austria before its official recognition. Results indicated societal support throughout all socio-demographic strata. A logistic regression showed that, besides socio-demographics and information level, place attachment had a significant influence on the acceptance of the biosphere reserve. Supporters and opponents showed both high place identity and dependence, while waverers scored low on these dimensions. Results indicate that place attachment is relevant for the design of participatory processes as well as for developing management policies for biosphere reserves. 相似文献
732.
Bison and cattle grazing management,bare ground coverage,and links to suspended sediment concentrations in grassland streams
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Bartosz P. Grudzinski Melinda D. Daniels Kyle Anibas David Spencer 《Journal of the American Water Resources Association》2016,52(1):16-30
This study quantified the impact of bison and cattle grazing management practices on bare ground coverage at the watershed, riparian, and forested riparian scales within the Flint Hills ecoregion in Kansas. We tested for correlations between bare ground coverage and fluvial suspended sediment concentrations during base‐flow and storm‐flow events. We used remotely sensed imagery combined with field surveys to classify ground cover and quantify the presence of bare ground. Base‐flow water samples were collected bi‐monthly during rain‐free periods and 24 h following precipitation events. Storm‐flow water samples were collected on the rising limb of the hydrograph, using single‐stage automatic samplers. Ungrazed treatments contained the lowest coverage of bare ground at the watershed, riparian, and forested riparian scales. Bison treatments contained the highest coverage of bare ground at the watershed scale, while high‐density cattle treatments contained the highest coverage of bare ground at the riparian and forested riparian scales. In bison and cattle‐grazed treatments, a majority of bare ground was located near fence lines, watershed boundaries, and third‐ and fourth‐order stream segments. Inorganic sediment concentrations at base flow were best predicted by riparian bare ground coverage, while storm‐flow sediment concentrations were best predicted by watershed scale bare ground coverage. 相似文献
733.
Augmenting Watershed Model Calibration with Incorporation of Ancillary Data Sources and Qualitative Soft Data Sources
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Haw Yen Michael J. White James C. Ascough II Douglas R. Smith Jeffrey G. Arnold 《Journal of the American Water Resources Association》2016,52(3):788-798
Watershed simulation models such as the Soil & Water Assessment Tool (SWAT) can be calibrated using “hard data” such as temporal streamflow observations; however, users may find upon examination of model outputs, that the calibrated models may not reflect actual watershed behavior. Thus, it is often advantageous to use “soft data” (i.e., qualitative knowledge such as expected denitrification rates that observed time series do not typically exist) to ensure that the calibrated model is representative of the real world. The primary objective of this study is to evaluate the efficacy of coupling SWAT‐Check (a post‐evaluation framework for SWAT outputs) and IPEAT‐SD (Integrated Parameter Estimation and Uncertainty Analysis Tool‐Soft & hard Data evaluation) to constrain the bounds of soft data during SWAT auto‐calibration. IPEAT‐SD integrates 59 soft data variables to ensure SWAT does not violate physical processes known to occur in watersheds. IPEAT‐SD was evaluated for two case studies where soft data such as denitrification rate, nitrate attributed from subsurface flow to total discharge ratio, and total sediment loading were used to conduct model calibration. Results indicated that SWAT model outputs may not satisfy reasonable soft data responses without providing pre‐defined bounds. IPEAT‐SD provides an efficient and rigorous framework for users to conduct future studies while considering both soft data and traditional hard information measures in watershed modeling. 相似文献
734.
Temporal Trends in the Spatial Distribution of Impervious Cover Relative to Stream Location
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J. Wickham A. Neale M. Mehaffey T. Jarnagin D. Norton 《Journal of the American Water Resources Association》2016,52(2):409-419
Use of impervious cover is transitioning from an indicator of surface water condition to one that also guides and informs watershed planning and management, including Clean Water Act (33 U.S.C. §1251 et seq.) reporting. Whether it is for understanding surface water condition or planning and management, impervious cover is most commonly expressed as summary measurement (e.g., percentage watershed in impervious cover). We use the National Land Cover Database to estimate impervious cover in the vicinity of surface waters for three time periods (2001, 2006, 2011). We also compare impervious cover in the vicinity of surface waters to watershed summary estimates of impervious cover for classifying the spatial pattern of impervious cover. Between 2001 and 2011, surface water shorelines (streams and water bodies) in the vicinity of impervious cover increased nearly 10,000 km. Across all time periods, approximately 27% of the watersheds in the continental United States had proximally distributed impervious cover, i.e., the percentage of impervious cover in the vicinity of surface waters was higher than its watershed summary expression. We discuss how impervious cover spatial pattern can be used to inform watershed planning and management, including reporting under the Clean Water Act. 相似文献
735.
The Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) have recently launched themselves as the UN-sanctioned instrument for conserving nature. They seek to establish themselves as the authority in this field alongside the well-known Intergovernmental Panel on Climate Change in climate science. Quickly following or even before recent publication of their conceptual framework in two biology journals, they were already underway building upon it. This headlong push, we believe, is ill advised. We show how the framework is unsound as a foundation for further work—in a number of ways and perhaps even by its authors’ own lights. It is therefore urgent that the IPBES thoroughly and thoughtfully reconsider their framework before too much effort is wasted. 相似文献
736.
Institutional Constraints on Cost‐Effective Water Management: Selenium Contamination in Colorado's Lower Arkansas River Valley
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Misti D. Sharp Dana L.K. Hoag Ryan T. Bailey Erica C. Romero Timothy K. Gates 《Journal of the American Water Resources Association》2016,52(6):1420-1432
Ground and surface water selenium (Se) contamination is problematic throughout the world, leading to harmful impacts on aquatic life, wildlife, livestock, and humans. A groundwater reactive transport model was applied to a regional‐scale irrigated groundwater system in the Lower Arkansas River Basin in southeastern Colorado to identify management practices that remediate Se contamination. The system has levels of surface water and groundwater Se concentrations exceeding the respective chronic standard and guidelines. We evaluate potential solutions by combining the transport model with an assessment of the cost to employ those practices. We use a framework common in economics and engineering fields alike, the Pareto frontier, to show the impact of four different best management practices on the tradeoffs between Se and cost objectives. We then extend that analysis to include institutional constraints that affect the economic feasibility associated with each practice. Results indicate that although water‐reducing strategies have the greatest impact on Se, they are the hardest for farmers to implement given constraints common to western water rights institutions. Therefore, our analysis shows that estimating economic and environmental tradeoffs, as is typically done with a Pareto frontier, will not provide an accurate picture of choices available to farmers where institutional constraints should also be considered. 相似文献
737.
Mitigating urban sprawl effects: a collaborative tree and shade intervention in Phoenix,Arizona, USA
Michael J. Bernstein Arnim Wiek Katja Brundiers Kimberly Pearson Amy Minowitz Braden Kay 《Local Environment》2016,21(4):414-431
Communities in Phoenix are confronted with numerous challenges that adversely affect human health and safety, with disproportionate impacts on low-income communities. While some challenges are being addressed at the city level, new alliances at the neighbourhood level are initiating community development programmes and projects. This article reports on an intervention study carried out in collaboration with community representatives, city staff, and non-profit organisations to mitigate adverse effects of urban sprawl in the Sky Harbour Neighbourhood in Phoenix. Participatory research was conducted to design and test a tree and shade intervention. Challenges associated with navigating community desires and broader principles of sustainable development are discussed. The study offers a replicable and adaptable intervention research design aimed at empowering communities to meet urban challenges. 相似文献
738.
Eric D. Carter 《Local Environment》2016,21(1):3-23
This paper presents the results of ethnographic research conducted with several environmental justice (EJ) organisations in Latino communities of Los Angeles, California. Traditional EJ politics revolves around research and advocacy to reduce discriminatory environmental exposures, risks, and impacts. However, I argue that in recent years there has been a qualitative change in EJ politics, characterised by four main elements: (1) a move away from the reaction to urban environmental “bads” (e.g. polluting industries) in the city towards a focus on the production of nature in the city; (2) strategies that are less dependent on the legal, bureaucratic, and technical “regulatory route”; (3) the formation of a distinctive “Latino environmental ethic” that offers a more complex consideration of the place of race in EJ organising; and (4) a spatial organisation of EJ politics that moves away from hyperlocal, vertical organisation towards diversified city-wide networks that include EJ organisations, mainstream environmental groups, nonprofits, foundations, and entrepreneurs. This shift in EJ movement politics is shaped by broader political-economic changes, including the shift from post-Fordist to neoliberal and now green economy models of urban development; the influence of neoliberal multiculturalism in urban politics; and the increasingly prominent role of Latinos in city, state, and national politics. New spaces of Latino EJ also reflect the ambitions of Los Angeles as a global city, with urban growth increasingly framed in an international discourse of sustainability that combines quality of life, environmental, and economic development rationales. 相似文献
739.
David M. Oliver Nick D. Hanley Melanie van Niekerk David Kay A. Louise Heathwaite Sharyl J. M. Rabinovici Julie L. Kinzelman Lora E. Fleming Jonathan Porter Sabina Shaikh Rob Fish Sue Chilton Julie Hewitt Elaine Connolly Andy Cummins Klaus Glenk Calum McPhail Eric McRory Alistair McVittie Amanna Giles Suzanne Roberts Katherine Simpson Dugald Tinch Ted Thairs Lisa M. Avery Andy J. A. Vinten Bill D. Watts Richard S. Quilliam 《Ambio》2016,45(1):52-62
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations. 相似文献
740.
Ryan A. Sponseller Michael J. Gundale Martyn Futter Eva Ring Annika Nordin Torgny Näsholm Hjalmar Laudon 《Ambio》2016,45(2):175-187
Nitrogen (N) availability plays multiple roles in the boreal landscape, as a limiting nutrient to forest growth, determinant of terrestrial biodiversity, and agent of eutrophication in aquatic ecosystems. We review existing research on forest N dynamics in northern landscapes and address the effects of management and environmental change on internal cycling and export. Current research foci include resolving the nutritional importance of different N forms to trees and establishing how tree–mycorrhizal relationships influence N limitation. In addition, understanding how forest responses to external N inputs are mediated by above- and belowground ecosystem compartments remains an important challenge. Finally, forestry generates a mosaic of successional patches in managed forest landscapes, with differing levels of N input, biological demand, and hydrological loss. The balance among these processes influences the temporal patterns of stream water chemistry and the long-term viability of forest growth. Ultimately, managing forests to keep pace with increasing demands for biomass production, while minimizing environmental degradation, will require multi-scale and interdisciplinary perspectives on landscape N dynamics. 相似文献