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951.
952.
水分管理与秸秆施用对稻田CH4和N2O排放的影响 总被引:30,自引:0,他引:30
2000年6~10月在南京近郊江宁区实施大田试验.主要研究了水稻生长季常规灌溉和连续淹水条件下有机质(小麦秸杆)不同施用量(0,2.25,4.5t/hm2)对稻田CH4和N2O排放的影响.结果表明,在连续淹水条件下,CH4排放量与秸杆施用量成正比,N2O排放与秸杆施用量成反比.烤田的N2O的排放量在施用2.25t/hm2秸杆与对照之间无明显差异,但施用4.5t/hm2秸杆处理其N2O的排放量仅为对照或施用2.25t/hm2秸杆处理下的13%左右.综合考虑水稻生长季CH4和N2O排放的全球增温潜势(GWP),在增加有机质的施用量(如按4.5t/hm2施用量秸杆还田)的情况下,烤田的GWP只占连续淹水处理的60%,是减少稻田CH4和N2O综合温室效应的一种有效措施. 相似文献
953.
我国核能利用与能源可持续发展探讨 总被引:1,自引:0,他引:1
阐述了我国目前的能源利用状况,火电与核电对环境影响的比较,核废物的处理技术及核电的安全性等,指出大力发展高效清洁的核电是我国实施可持续发展战略的必然要求。 相似文献
954.
吐鲁番盆地的生态灾害具有种类多、危害面广、危害程度深等特征,并严重制约着该区绿洲经济的持续稳定发展。本文分析了每种生态灾害发生的原因、危害程度及地区分布,并提出了生态灾害调控的基本原则;综合整体性、区域分异性、持续性.最后探讨了该地生态灾害调控的一些具体措施。 相似文献
955.
Nabil G. Shafike Lucien Duckstein Thomas Maddock 《Journal of the American Water Resources Association》1992,28(1):33-43
ABSTRACT: Multicriterion decision making (MCDM) techniques were used to analyze a groundwater contamination management problem from the viewpoint of conflicting multiple objectives. The groundwater management model was used to find a compromise strategy for trading off fresh water supply, containment of the waste, and total pumping cost in a hypothetical confined aquifer affected by previous waste disposal action. A groundwater flow model was used to formulate the hydraulic constraints. A linear system model was used to describe drawdown and velocity as functions of the decision variables which were pumping rates. The model determines the pumping location and rates. A modified c-constraint method was used to generate the set of nondominated solutions which were the alternative compromise strategies. Three different MCDM techniques, Compromise programming (CP), ELECTRA II and MCQA II, were used to select a “satisficing” alternative. Analysis of the results showed that, although these techniques follow different principles, the same preferred strategies were reached. Also, it was noticed that maintaining high groundwater velocities is expensive and difficult. In order to meet a two year target date, large amounts of water had to be pumped. Therefore, rapid restoration results in large pumping volumes and high costs. 相似文献
956.
滇东南地区自然旅游资源丰富多彩,以喀斯特山水风光为其主体特色;人文旅游资源绚丽灿烂,以少数民族风情为其鲜明特征。本区区位条件优越,交通运输形成网络,潜在客源市场广阔,为该区旅游资源的进一步开发奠定了基础。根据该区旅游资源的分布、交通条件、经济承受能力和接待条件,笔者认为近期开发的重点是:①开发喀斯特景观系列旅游产品;②建设建水、罗平、邱北3个旅游集散中心;③开辟4条旅游主干线;④开发8大旅游商品系列。 相似文献
957.
The huge migration of rural workers has new characteristics such as the bad order, high degree of concentration, low level of collective action, marginality in social status, unfair treatment, difficult integration of the new generation, and the new return trend of rural migrants, which causes 'urban diseases' in China. Countermeasures should be taken to develop medium-sized and small cities, integrate the labor market of the city and countryside, provide necessary public services, social security and vocational training, guide the rural migrant workers to return rationally, and help the new generation live in harmony with urban residents. 相似文献
958.
To improve quality of life as well as the adaptive capacity in the city of Rotterdam over the past 15 years there has been a lot of focus on improving green infrastructure and finding new ways for integrated planning. As many cities face similar challenges they are looking for novel approaches in urban ecosystem governance. The Rotterdam case can be an interesting example but can also reveal new questions to be researched.Before local policies and projects where developed a regional and urban green blue vision of how to improve overall quality of life using green infrastructure were developed. This provided policy frameworks for politicians, policymakers and other actors. Later on the same was done with Urban Waterplan 2, using the Rotterdam Watercity 2030 vision document as a basis. This vision was the result of a stakeholder based planning process which was made for the International Architecture Biennale 2005. Within these frameworks many interesting projects have been built and tested in the city and city region; ranging from a) a roof park over a railway yard to connect neighbourhoods to the waterfront, to b) water squares and c) digging new waterways with connected walking and biking routes. To go from projects to an overall implementation at city level required tools and approaches for better decision making. For the ‘Dakpark’ project as well as for the Zomerhofkwartier, the first climate proof neighbourhood in the city, stakeholder sessions were held and plans were drawn together with urban planners and landscape architects. To feed these processes even better and to know what would be an optimal solution for certain challenges, city data were studied and linked to scalable GIS mapping in the ‘smart city planner’. This tool gives the decision maker the possibility to quickly have an overview of an area and can be used in a stakeholder process to provide relevant additional information and to define joint projects. The tool makes it possible to do this for all 90 neighbourhoods in the city.Overall the urban ecosystem governance in the city of Rotterdam has – with trial and error- lead to a series of innovative projects. The next steps are acceleration and scaling up to city and regional level. Valuing the crucial role of green blue infrastructure for several aspects of the quality of life in cities are paramount. 相似文献
959.
以基于风险的QHSE管理策略和专业化管理方法为切入点,从专业化策划要求、专业化模块建设、专业化审核应用等方面对专业化审核技术进行探讨。 相似文献
960.
贫困山区名牌战略初探:以渝鄂湘黔接壤区为例 总被引:3,自引:0,他引:3
陈国阶 《长江流域资源与环境》1999,8(2):147-152
渝鄂湘黔接壤区是全国闻名的贫困山区。在这里,开发名牌产品,实行名牌战略,不仅是必要的,而且是可能的。有可能发展成为名牌的产品包括:历史上已有一定知名度的传统产品;山区无污染的绿色产品;拥有较强的科技含量又已有质量优势的工业产品;以天然植物为开发对象的现代生物化工产品;精美的少数民族工艺产品等。推行名牌战略,应提高认识,坚定信心,搞好计划;应巩固和扩大已有的名牌产品;对有潜力的产品应分层次、顺序,先 相似文献