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941.
D.M. Nover M.S. Dogan R. Ragatz L. Booth J. Medellín‐Azuara J.R. Lund J.H. Viers 《Journal of the American Water Resources Association》2019,55(3):759-771
Increasing reservoir storage is commonly proposed to mitigate increasing water demand and provide drought reserves, especially in semiarid regions such as California. This paper examines the value of expanding surface reservoir capacity in California using hydroeconomic modeling for historical conditions, a future warm‐dry climate, and California's recently adopted policy to end groundwater overdraft. Results show expanding surface storage capacity rarely provides sizable economic value in most of California. On average, expanding facilities north of California's Delta provides some benefit in 92% of 82 years modeled under historical conditions and in 61% of years modeled in a warm‐dry climate. South of California's Delta, expanding storage capacity provides no benefits in 14% of years modeled under historical conditions and 99% of years modeled with a warm‐dry climate. Results vary across facilities between and within regions. The limited benefit of surface storage capacity expansion to statewide water supply should be considered in planning California's water infrastructure. 相似文献
942.
Dinuke Munasinghe Sagy Cohen Yu‐Fen Huang Yin‐Phan Tsang Jiaqi Zhang Zheng Fang 《Journal of the American Water Resources Association》2018,54(4):834-846
The objective of this study was to determine the accuracy of five different digital image processing techniques to map flood inundation extent with Landsat 8–Operational Land Imager satellite imagery. The May 2016 flooding event in the Hempstead region of the Brazos River, Texas is used as a case study for this first comprehensive comparison of classification techniques of its kind. Five flood water classification techniques (i.e., supervised classification, unsupervised classification, delta‐cue change detection, Normalized Difference Water Index [NDWI], modified NDWI [MNDWI]) were implemented to characterize flooded regions. To identify flood water obscured by cloud cover, a digital elevation model (DEM)–based approach was employed. Classified floods were compared using an Advanced Fitness Index to a “reference flood map” created based on manual digitization, as well as other data sources, using the same satellite image. Supervised classification yielded the highest accuracy of 86.4%, while unsupervised, MNDWI, and NDWI closely followed at 79.6%, 77.3%, and 77.1%, respectively. Delta‐cue change detection yielded the lowest accuracy with 70.1%. Thus, supervised classification is recommended for flood water classification and inundation map generation under these settings. The DEM‐based approach used to identify cloud‐obscured flood water pixels was found reliable and easy to apply. It is therefore recommended for regions with relatively flat topography. 相似文献
943.
Projecting Canadian Prairie Runoff for 2041–2070 with North American Regional Climate Change Assessment Program (NARCCAP) Data 下载免费PDF全文
Jeannine‐Marie St‐Jacques Yuliya Andreichuk David J. Sauchyn Elaine Barrow 《Journal of the American Water Resources Association》2018,54(3):660-675
The South Saskatchewan River Basin (SSRB) of Alberta, Canada, is semiarid and under severe water stress due to increasing human demands. We present the first examination of projected changes in SSRB runoff from a large set of North American Regional Climate Change Assessment Program regional climate models (RCMs) plus one Coordinated Regional Climate Downscaling Experiment RCM. We used six different runoff estimation methods: total surface and subsurface runoff (total runoff), surface runoff, and four estimations based on Budyko functions. Most RCM estimations showed substantial biases and distribution differences when compared to observed data; thus bias correction was necessary. Total runoff was the best of the six variables in modeling observed runoff for each of the four SSRB subbasins. Projected total runoff for 2041–2070 shows a geographic gradient in the SSRB, with possible drying in the southern Oldman River subbasin and possible increased runoff in the northernmost Red Deer River subbasin. A shift to an earlier spring peak in runoff and drier late summer, with a need for increased irrigation, should be expected. In a first examination of the important question of projected changes in interannual variability, we show increasing magnitude. This result further adds to adaptation challenges over the course of this century in this basin, which is already largely closed to further allocation. 相似文献
944.
D. Marchal‐Ségault G. Laugé 《Journal of environmental science and health. Part. B》2013,48(3):411-428
Abstract Two types of reactions were observed on the alteration of Drosophila vitellogenesis by the four fungicides used in this study. Dithane®M45 resulted in stimulation associated with egg retention. However, the other three fungicides (Benlate®, Bouillie bordelaise® and Euparène®) resulted in inhibition to a varying degree. Although the inhibition was comparatively limited due to Benlate® it induced an egg retention. The inhibition was very high due to Bouillie bordelaise® and Euparène®. With Bouillie bordelaise® an egg retention occured together with the reduction of vitellogenesis and caused an increase in the rate of the follicle resorption. The latter depended on the duration of treatment. With Euparène®, no egg retention was observed and the toxicity was only noticed on vitellogenesis. 相似文献
945.
DIANA M. PIETRI GEORGINA G. GURNEY NANCY BENITEZ‐VINA AUDREY KUKLOK SARA M. MAXWELL LIBBY WHITING MICHAEL A. VINA LEKELIA D. JENKINS 《Conservation biology》2013,27(5):958-967
Seasoned conservation researchers often struggle to bridge the research–implementation gap and promote the translation of their work into meaningful conservation actions. Graduate students face the same problems and must contend with obstacles such as limited opportunities for relevant interdisciplinary training and a lack of institutional support for application of research results. However, students also have a crucial set of opportunities (e.g., access to academic resources outside their degree programs and opportunities to design research projects promoting collaboration with stakeholders) at their disposal to address these problems. On the basis of results of breakout discussions at a symposium on the human dimensions of the ocean, a review of the literature, and our own experiences, we devised recommendations on how graduate students can create resources within their academic institutions, institutionalize resources, and engage with stakeholders to promote real‐world conservation outcomes. Within their academic institutions, graduate students should foster links to practitioners and promote knowledge and skill sharing among students. To institutionalize resources, students should cultivate student leaders and faculty sponsors, systematically document their program activities, and engage in strategic planning to promote the sustainability of their efforts. While conducting research, students should create connections to and engage actively with stakeholders in their relevant study areas and disseminate research results both to stakeholders and the broader public. Our recommendations can serve as a template for graduate students wishing to bridge the research–implementation gap, both during their current studies and in their future careers as conservation researchers and practitioners. Recomendaciones Prácticas para Ayudar a Estudiantes a Vencer la Brecha entre Investigación e Implementación y Promover la Conservación 相似文献
946.
This paper reports on an examination of data on how local residents in Tuscaloosa, a mid‐sized city in the state of Alabama, United States, responded to Hurricane Ivan of September 2004. The evaluation revealed that an integrated connection to community‐level communication resources—comprising local media, community organisations and interpersonal networks—has a direct impact on the likelihood of engaging in pre‐hurricane preparedness activities and an indirect effect on during‐hurricane preparedness activities. Neighbourhood belonging mediated the relation between an integrated connection to community‐level communication resources and during‐hurricane preparedness activities. Neighbourhood belonging was determined to increase the likelihood of taking preparedness actions during Hurricane Ivan, but not prior to it. In addition, we discovered an interesting pattern for two different types of risk perceptions: social and personal risk perceptions. Social risk perceptions increase the likelihood of taking preventative steps before a hurricane while personal risk perceptions are positively related to engaging in preventative action during a hurricane. 相似文献
947.
Jeng-Chung Chen Wei-Hsin Chen Eric Davila Cheng-Hsien Tsai 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1356-1366
Abstract Conflicting goals affecting solid waste management are explored in this paper to find the best implementation of resource recovery with a small-scale waste-to-energy process. Recycling paper and plastic material often leaves a shortage of thermal energy to support incineration that forces operators to supplement the process with auxiliary fuels. Although there are considerable profits to be made from material recovery, the increase of fuel usage causes conflict given that it is cost prohibitive. A series of trials performed on a small-scale 1.5-t/day incineration plant with a cyclone heat recovery system found that material recycling can impede performance. Experimental results are expressed as empirical regression formulas with regard to combustion temperature, energy transfer, and heat recovery. Process optimization is possible if the waste moisture content remains <30%. To test the robustness of the optimization analysis, a series of sensitivity analyses clarify the extent of material recycling needed with regard to plastic, paper, and metal. The experiments also test whether the moisture in the waste would decrease when recycling paper because of its exceptional capacity to absorb moisture. Results show that recycling paper is strongly recommended when the moisture content is >20%, whereas plastic recycling is not necessary at that moisture condition. Notably, plastic recovery reduces the heat needed to vaporize the water content of the solid waste, thus it is recommended only when the moisture content is <10%. For above-normal incineration temperatures, plastic recycling is encouraged, because it removes excess energy. Metal is confirmed as an overall priority in material recycling regardless of the moisture content of the incoming waste. 相似文献
948.
949.
Gretchen Lebuhn Sam Droege Edward F. Connor Barbara Gemmill‐Herren Simon G. Potts Robert L. Minckley Terry Griswold Robert Jean Emanuel Kula David W. Roubik Jim Cane Karen W. Wright Gordon Frankie Frank Parker 《Conservation biology》2013,27(1):113-120
Recently there has been considerable concern about declines in bee communities in agricultural and natural habitats. The value of pollination to agriculture, provided primarily by bees, is >$200 billion/year worldwide, and in natural ecosystems it is thought to be even greater. However, no monitoring program exists to accurately detect declines in abundance of insect pollinators; thus, it is difficult to quantify the status of bee communities or estimate the extent of declines. We used data from 11 multiyear studies of bee communities to devise a program to monitor pollinators at regional, national, or international scales. In these studies, 7 different methods for sampling bees were used and bees were sampled on 3 different continents. We estimated that a monitoring program with 200–250 sampling locations each sampled twice over 5 years would provide sufficient power to detect small (2–5%) annual declines in the number of species and in total abundance and would cost U.S.$2,000,000. To detect declines as small as 1% annually over the same period would require >300 sampling locations. Given the role of pollinators in food security and ecosystem function, we recommend establishment of integrated regional and international monitoring programs to detect changes in pollinator communities. Detección de Declinaciones de Insectos Polinizadores a Escalas Regional y Global 相似文献
950.
GILBERT BAASE ADUM MARKUS PETER EICHHORN WILLIAM ODURO CALEB OFORI‐BOATENG MARK‐OLIVER RÖDEL 《Conservation biology》2013,27(2):354-363
There is a lack of quantitative information on the effectiveness of selective‐logging practices in ameliorating effects of logging on faunal communities. We conducted a large‐scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest‐dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance‐tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance‐tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low‐intensity logging (≤3 trees/ha) a minimum 20‐year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages. Recuperación de Ensambles de Anfibios en Dos Etapas Después de la Tala Selectiva de Bosques Tropicales 相似文献