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201.
Ensuring the persistence of at-risk species depends on implementing conservation actions that ameliorate threats. We developed and implemented a method to quantify the relative importance of threats and to prioritize recovery actions based on their potential to affect risk to Mojave desert tortoises (Gopherus agassizii). We used assessments of threat importance and elasticities of demographic rates from population matrix models to estimate the relative contributions of threats to overall increase in risk to the population. We found that urbanization, human access, military operations, disease, and illegal use of off highway vehicles are the most serious threats to the desert tortoise range-wide. These results suggest that, overall, recovery actions that decrease habitat loss, predation, and crushing will be most effective for recovery; specifically, we found that habitat restoration, topic-specific environmental education, and land acquisition are most likely to result in the greatest decrease in risk to the desert tortoise across its range. In addition, we have developed an application that manages the conceptual model and all supporting information and calculates threat severity and potential effectiveness of recovery actions. Our analytical approach provides an objective process for quantifying threats, prioritizing recovery actions, and developing monitoring metrics for those actions for adaptive management of any at-risk species.  相似文献   
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To evaluate the long term sustainability of water withdrawals in the United States, a county level analysis of the availability of renewable water resources was conducted, and the magnitudes of human withdrawals from surface water and ground water sources and the stored water requirements during the warmest months of the year were evaluated. Estimates of growth in population and electricity generation were then used to estimate the change in withdrawals assuming that the rates of water use either remain at their current levels (the business as usual scenario) or that they exhibit improvements in efficiency at the same rate as observed over 1975 to 1995 (the improved efficiency scenario). The estimates show several areas, notably the Southwest and major metropolitan areas throughout the United States, as being likely to have significant new storage requirements with the business‐as‐usual scenario, under the condition of average water availability. These new requirements could be substantially eliminated under the improved efficiency scenario, thus indicating the importance of water use efficiency in meeting future requirements. The national assessment identified regions of potential water sustainability concern; these regions can be the subject of more targeted data collection and analyses in the future.  相似文献   
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In a closed aerated laboratory soil test, volatilization and mineralization of 2,6-dichlorobenzonitrile-14C is negligible within 61 days. The major soil residues are parent compound, 2,6-dichlorobenzamide and unextractable residues.  相似文献   
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In the area of end-of-life vehicle (ELV) recycling, Japan passed the Automobile Recycling Law in January 2005, the first in Asia. Korea followed suit with the passage of the resource circulation method in 2009. China is expected make a new recycling law in 2011. In contribution to these initiatives, Tohoku University made a comparative analysis of ELV recycling laws, advance dismantling experiments and scenario analysis to promote international cooperation. This is envisioned to introduce ELV recycling system in Japan, China and Korea and in developing countries as well.  相似文献   
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Environmental Science and Pollution Research - The COVID-19 pandemic has created unprecedented human health crisis in recent global history with rippling social and economic effects. The outbreak...  相似文献   
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Environmental Science and Pollution Research - A solid polymer, poly[(sodium methacrylate)-co-2-(methacryloyloxy)ethyl acetoacetate], p(MAA-co-MEAA) was synthesized and then grafted onto carbon...  相似文献   
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