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711.
Freshwater ecosystems provide irreplaceable services for both nature and society. The quality and quantity of freshwater affect biogeochemical processes and ecological dynamics that determine biodiversity, ecosystem productivity, and human health and welfare at local, regional and global scales. Freshwater ecosystems and their associated riparian habitats are amongst the most biologically diverse on Earth, and have inestimable economic, health, cultural, scientific and educational values. Yet human impacts to lakes, rivers, streams, wetlands and groundwater are dramatically reducing biodiversity and robbing critical natural resources and services from current and future generations. Freshwater biodiversity is declining rapidly on every continent and in every major river basin on Earth, and this degradation is occurring more rapidly than in terrestrial ecosystems. Currently, about one third of all global freshwater discharges pass through human agricultural, industrial or urban infrastructure. About one fifth of the Earth’s arable land is now already equipped for irrigation, including all the most productive lands, and this proportion is projected to surpass one third by midcentury to feed the rapidly expanding populations of humans and commensal species, especially poultry and ruminant livestock. Less than one fifth of the world’s preindustrial freshwater wetlands remain, and this proportion is projected to decline to under one tenth by midcentury, with imminent threats from water transfer megaprojects in Brazil and India, and coastal wetland drainage megaprojects in China. The Living Planet Index for freshwater vertebrate populations has declined to just one third that of 1970, and is projected to sink below one fifth by midcentury. A linear model of global economic expansion yields the chilling prediction that human utilization of critical freshwater resources will approach one half of the Earth’s total capacity by midcentury. Although the magnitude and growth of the human freshwater footprint are greater than is generally understood by policy makers, the news media, or the general public, slowing and reversing dramatic losses of freshwater species and ecosystems is still possible. We recommend a set of urgent policy actions that promote clean water, conserve watershed services, and restore freshwater ecosystems and their vital services. Effective management of freshwater resources and ecosystems must be ranked amongst humanity’s highest priorities.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01318-8) contains supplementary material, which is available to authorized users.  相似文献   
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Environment Systems and Decisions - Rural areas face well known and distinctive health care challenges that can limit their resilience in the face of health emergencies such as the COVID-19...  相似文献   
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Mixed findings emerge from this ex post Cost-Benefit Analysis of a major water investment programme in Ireland. Water supply and conservation investments, where most benefits were internal, generally proved worthwhile. Wastewater investments could not be analysed fully due to lack of environmental data. Here the authors estimated the level of ‘willingness-to-pay’ that would have been required to ‘justify’ the investments. In some cases the required level seemed implausibly high, raising questions as to prioritisation of projects. The authors recommend a more systematic approach to recording environmental benefits in future investment programmes, the next likely wave being in new EU member states seeking to meet environmental standards. The EU, as likely co-funder of these investments, should require systematic recording of environmental benefits.  相似文献   
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在脱贫攻坚的大背景下,社会工作专业力量积极参与农村精准扶贫,资源整合是其中的一个重要议题。当前农村贫困对象的资源呈现总体匮乏、资源无联动、资源流失的状态。在农村精准扶贫中,社会工作资源整合需要使贫困对象碎片化的资源状态能够系统化。开展社会工作资源整合,首先需要评估贫困对象的资源需求,然后盘点贫困对象现有资源,并优化资源输送机制,再次需要对整合的资源进行管理与评估。在农村精准扶贫中,也需要反思社会工作资源整合的本土化问题,以及思考后扶贫时代如何针对农村相对贫困群体开展社会工作资源整合服务。  相似文献   
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ABSTRACT: Granular matrix soil moisture sensors were used to control urban landscape irrigation in Boulder, Colorado, during 1997. The purpose of the study was to evaluate the effectiveness and reliability of the technology for water conservation. The 23 test sites included a traffic median, a small city park, and 21 residential sites. The results were very good. The system limited actual applications to an average of 73 percent of the theoretical requirement. This resulted in an average saving of $331 per installed sensor. The sensors were highly reliable. All 23 sensors were placed in service at least three years prior to the 1997 study during earlier studies. Of these, only two had failed by the beginning of the 1997 study, both due to external factors. Including replacement of these failed sensors, the total repair cost for the 1997 irrigation season was less than $270. The effort required to maintain each system was small, only about 6–7 minutes per visit. Each site was visited weekly for this study, but less frequent visits could be made in practice. The sensors observed in this study performed well, significantly reduced water consumption, and were easy to monitor and maintain. Soil moisture sensors appear to be a useful and economical tool for urban water conservation.  相似文献   
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Two of the most frequently heard questions from environmental managers are “What should my company do about ISO 14000?” and “How can I use computer systems to reduce my staff's paperwork burden?” There are experts available to answer each of these questions, but thus far there has been little attention paid to how the two intersect and reinforce each other. This article explores this intersection and helps environmental managers implement information systems that have lasting value and, at the same time, support the ISO 14000 effort.  相似文献   
720.
OBJECTIVE: Impaired drivers and other high-risk road users are less likely to use their safety belts, thus increasing the risk of fatal injury in the event of a crash. Although safety belt laws have been shown to increase wearing rates for daytime non-crash-involved drivers and their front-seat passengers, little evidence is available on the effect these laws have on belt usage by crash-involved drinking drivers and their passengers. METHODS: This study evaluated the influence of primary safety belt law upgrades from secondary laws on front-seat occupants of passenger cars driven by drinking drivers in fatal crashes in five states: California, Illinois, Maryland, Michigan, and Washington. The outcome measures used to evaluate these law upgrades were (1) the change in safety belt usage rates of front-seat occupants in passenger cars driven by drinking drivers in fatal crashes and (2) the change in alcohol-related front-seat occupant fatalities in passenger cars driven by drinking drivers. RESULTS: Four of the five states demonstrated increases in safety belt use by front-seat occupants of passenger cars of drinking drivers in fatal crashes following the upgrade to primary safety belt laws. Three states (California, Michigan, and Washington) experienced significant reductions in the number of front-seat occupant fatalities in vehicles driven by drinking drivers. CONCLUSIONS: The adoption of primary law upgrades was associated with significant increases in safety belt use (four of five states) and significant reductions in fatalities among high-risk occupants (i.e., front-seat occupants involved in fatal crashes in vehicles driven by drinking drivers) in three of the five states studied.  相似文献   
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