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The development of an environmental information system necessitates a phased implementation approach. Phase 1 includes the elements that are traditionally viewed as comprising monitoring and assessment activities. Analysis tools for interpretive work are identified including statistics, modelling, and GIS. Phase 2 follows the information flow beyond project reporting to examine the process of decision making. The inclusion of other forms of knowledge beyond the strictly scientific is necessary where the development of multi-sectoral decisions must be made. Phase 3 extends the decision-making process to the policy development and implementation field. This is accomplished by the inclusion of expert systems as advanced decision support systems which enable the manager to test various hypotheses and policy options prior to commitment. In addressing water resource issues, the importance of setting achievable and enforceable sectoral criteria and standards for industrial, agricultural, and drinking water supplies is discussed with reference to both usage and effluent criteria. Quality assurance and control is an area which must be critically addressed in any water resource project. The implementation of quality control programs must extend from the field sampling procedures and laboratory standard methods to both inter- and intra-laboratory tests and the development and maintenance of databases.  相似文献   
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This study investigated the disease suppression abilities of a compost amendment that was added to the conventional growing medium, yellow cedar sawdust, used in most British Columbia vegetable greenhouses. The compost amendment was produced in a controlled, in-vessel process primarily from greenhouse crop waste materials. The pathogen and cultivar under study were Fusarium oxysporum f. sp. radicis-lycopersici (FORL) on Dombito (FORL-susceptible) beefsteak greenhouse tomatoes. Significant reduction of Fusarium crown and root rot was also realized in tomato seedlings by applying compost amendment from several different batches, as a seed cover or plug substitute. In a greenhouse trial, disease suppression using a mixture of 2:1 sawdust to amendment by volume was shown to be most effective. As a result, the tomato yield over a nine-month growing season was improved by 74% where the medium was deliberately infested with FORL.  相似文献   
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城市二级污水灌溉对几种园林植物生长的影响   总被引:5,自引:1,他引:5  
以新疆乌鲁木齐市东郊七道弯污水处理厂二级出水为研究对象.开展了二级污水对几种园林植物(万寿菊、紫穗槐、高羊茅、早熟禾)生理、生态的影响研究。与对照组相比,结果表明,草坪草、紫穗槐叶绿素含量、净光合速率、地上部分生物量增加。  相似文献   
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The Sendai Framework for Disaster Risk Reduction 2015–2030 and the United Nations’ Sustainable Development Goals call for action to build back better in ways that leave no one behind. At the same time, ensuring a local voice is increasingly central to humanitarian engagement. These aims contrast with limited analysis of how local actors might be supported in these respects during response and recovery, and how far recommendations are specific or generalisable across richer and poorer national contexts. The paper begins by comparing lessons learnt by survivors and community organisations in Sint Maarten, Dutch Caribbean, following a high‐income state‐led response to Hurricane Irma in 2017 with the priorities of lower income, humanitarian‐led endeavours. The differences reveal the importance of economic resources as the basis for individual self‐reliance and a fragmented civil society with limited leadership ambitions in Sint Maarten. Strong cross‐cultural alignment nevertheless allows for a globally‐relevant and yet contextually‐sensitive framework for survivor‐led action and reconstruction.  相似文献   
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建立了加速溶剂萃取-固相萃取净化-高效液相色谱测定玉米作物中15种多环芳烃的方法,优化了试验条件.方法线性关系良好,15种多环芳烃的检出限在0.003 8~0.079μg/kg之间,空白加标试验的相对标准偏差在3.9%~11.7%之间,基质加标回收率在69.3%~115.3%之间.实际样品的测定结果表明,该方法分离效果...  相似文献   
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为了解可吸入颗粒物污染水平与气象因素之间的关系,从2008年9月—2010年2月采集乌鲁木齐市可吸入颗粒物样品,并对其随时间的变化特征及其与气象因素之间的相关性进行了统计分析。结果表明,采样时间内可吸入颗粒物中PM2.5和PM2.5-10的质量浓度的范围分别为38.2~468.7μg/m3和20.8~243.1μg/m3,平均浓度分别为134.2μg/m3和69.2μg/m3。可吸入颗粒物同时受几种气象因素的影响,其浓度与温度、能见度、风速呈负相关,与湿度呈正相关。  相似文献   
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新疆农业生态环境现状与绿洲生态农业建设探讨   总被引:3,自引:1,他引:2  
新疆是以农业生产为支柱产业地处半干旱半荒漠、生态环境比较脆弱的内陆地区。随着农业生产技术的不断更新、农资产品、化学物质的大量使用的工业生产中产生的污染物日益增加,新疆农业生态环境(局部)出现了许多新的问题。本文就新疆农业生态环境现状、发展趋势,及新疆绿洲生态农业建设与农业可持续发展等方面进行了分析探讨。  相似文献   
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