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491.
Australian governments have sought to invest in irrigation infrastructure to improve the efficiency of water delivery to rural properties and improve water supply and on-farm efficiency. A programme of rationalising irrigation infrastructure has attracted criticism and doubts about its likely success. Attitude theory in the form of the Reasoned Action Model was applied to understand the intentions of landowners to connect to a ‘modernised’ irrigation system. Attitudes towards connecting to the system, social norms and perceptions of control over the behaviour provided an explanation of intentions to connect. Actual financial capability and other variables were important in discriminating a group of landowners who had already connected to the modernised system from farmers who had not.  相似文献   
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Despite the largely theoretical risks for human morbidity from exposure to DDT (p, p′-dichlorodiphenyltrichloroethane), the reality that it is inexpensive and highly effective in reducing morbidity and mortality from malaria vectors has encouraged its continued use. Here we present data indicating that domestic fowl are potentially excellent sentinel species for detecting possible human exposures to DDT. In addition to measuring residues of DDT in chicken blood or eggs, a potential alternate analyte indicative of recent DDT exposure is the definitive metabolic product DDA (2,2-bis(4-chlorophenyl)acetic acid) in feces.  相似文献   
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Ten ways remote sensing can contribute to conservation   总被引:1,自引:0,他引:1       下载免费PDF全文
In an effort to increase conservation effectiveness through the use of Earth observation technologies, a group of remote sensing scientists affiliated with government and academic institutions and conservation organizations identified 10 questions in conservation for which the potential to be answered would be greatly increased by use of remotely sensed data and analyses of those data. Our goals were to increase conservation practitioners’ use of remote sensing to support their work, increase collaboration between the conservation science and remote sensing communities, identify and develop new and innovative uses of remote sensing for advancing conservation science, provide guidance to space agencies on how future satellite missions can support conservation science, and generate support from the public and private sector in the use of remote sensing data to address the 10 conservation questions. We identified a broad initial list of questions on the basis of an email chain‐referral survey. We then used a workshop‐based iterative and collaborative approach to whittle the list down to these final questions (which represent 10 major themes in conservation): How can global Earth observation data be used to model species distributions and abundances? How can remote sensing improve the understanding of animal movements? How can remotely sensed ecosystem variables be used to understand, monitor, and predict ecosystem response and resilience to multiple stressors? How can remote sensing be used to monitor the effects of climate on ecosystems? How can near real‐time ecosystem monitoring catalyze threat reduction, governance and regulation compliance, and resource management decisions? How can remote sensing inform configuration of protected area networks at spatial extents relevant to populations of target species and ecosystem services? How can remote sensing‐derived products be used to value and monitor changes in ecosystem services? How can remote sensing be used to monitor and evaluate the effectiveness of conservation efforts? How does the expansion and intensification of agriculture and aquaculture alter ecosystems and the services they provide? How can remote sensing be used to determine the degree to which ecosystems are being disturbed or degraded and the effects of these changes on species and ecosystem functions?  相似文献   
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