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Ikechukwu C. Ahams Willa Paterson Susana Garcia Richard Rushforth Benjamin L. Ruddell Alfonso Mejia 《Journal of the American Water Resources Association》2017,53(5):1147-1163
Conventional indicators of water use for urban areas account primarily for direct water use. In contrast, our objective here is to employ the water footprint (WF) concept and methodology to include the virtual or indirect water use to assess the production‐side and consumption‐side WF of 65 United States (U.S.) cities. The 65 cities include the largest metropolitan areas and some of the major mid‐sized cities in the U.S. We use metropolitan areas to define our city boundaries as this is the native spatial resolution of the main datasets used. To estimate the urban WFs, we integrated large and disparate datasets, including commodity flow (agricultural, livestock, and industrial commodities), water use, and socioeconomic data. By analyzing the estimated WF values, we found indirect water use accounts on average for 66% of the WF of consumption. We found some cities are net virtual water exporters (11 of 65) because they rely heavily on direct water uses or are heavy producers of industrial commodities. Also, WF patterns vary widely across the U.S. but regional patterns seem to emerge. For example, the dense cities of the U.S. northeast megaregion have a significantly low per capita WF relative to the other cities, while cities in the Gulf Coast megaregion have a significantly higher industrial WF of production and consumption. Furthermore, there is inequality in the WF of consumption where a few cities account for a disproportionate share of the total U.S. urban water uses. 相似文献
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Survival of Escherichia coli in zero-degree centigrade sea water 总被引:1,自引:0,他引:1
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Prioritizing Pacific Salmon Stocks for Conservation 总被引:3,自引:1,他引:2
Fred W. Allendorf David Bayles Daniel L. Bottom Kenneth P. Currens Christopher A. Frissell David Hankin James A. Lichatowich Willa Nehlsen Patrick C. Trotter & Thomas H. Williams 《Conservation biology》1997,11(1):140-152
Over 300 native stocks of Pacific salmon, steelhead, and coastal cutthroat trout (Oncorhynchus spp.) are at risk of extinction in the Pacific Northwest. With only limited resources available for conservation and recovery, prioritization of these stocks may become necessary if meaningful measures are to be implemented. We propose criteria by which prioritization may be guided. First, we rank stocks for risk of extinction, either by population viability analysis or by a set of surrogate measures. Then we rank stocks for biological consequences of extinction, using sets of questions designed to establish the genetic and evolutionary consequences and the ecological consequences if a stock were to become extinct. Together, these rankings allow stocks to be prioritized for a range of possible actions, with those stocks at highest risk and bearing the greatest biological consequences of extinction receiving attention first. Application of the prioritization process to 20 Pacific anadromous salmonid stocks worked as intended, although data limitations are considerable. The process is most likely to work successfully when applied to many stocks on which data exist, when several experts carry out the prioritization, and when the results are peer reviewed. 相似文献
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