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381.
This study presents an integrated framework for the analysis of options of agricultural development and natural resource management at the ecosystem level. Pujiang County in Zhejiang Province, China, is used as a case-study area. The IMGLP model is applied to maximize regional agricultural economic surplus and labor market conditions in Pujiang. The consequences of four poverty reduction strategies (intensification of production, diversification toward livestock production, land expansion, and exit from agriculture) are determined for a set of regional poverty and biodiversity indicators. Diversification seems to be the most promising poverty reduction strategy, but requires an efficient use of animal manure in cropping systems to avoid environmental problems. Improved nutrient management in cropping systems is effective in reducing the regional nitrogen surplus, but less effective in increasing per capita income. The exit strategy is beneficial for reducing poverty and achieving biodiversity, but may have important social consequences that are not addressed in this study. Further reduction of rural poverty is hampered by labor constraints during the harvesting period for high-value crops such as vegetables and fruits. These constraints can be overcome by intensive research and development in the field of agricultural mechanization.  相似文献   
382.
给出了清洁生产的定义:论述了开发和推广清洁产品的意义和为此所作的努力:归纳了产品生态设计的基本概念及其实施的主要途径。这些途径不是相互孤立的。而是相互关联与补充的,其中最主要的是要满足产品设计的环境准则,即要在产品的生命周期中体现污染预防的思想。  相似文献   
383.
Scenario study for a regional low-carbon society   总被引:1,自引:0,他引:1  
Japan should undertake drastic greenhouse gas (GHG) emission reductions by the middle of this century in order to mitigate climate change problems. Municipalities should design and execute scenarios toward a low-carbon society suited to their respective regions. This study describes long-term future visions developed for Shiga Prefecture targeting CO2 emission reductions of 30–50% by 2030, and presents scenarios to attain these targets, which are achievable with mild economic growth. For targets over a 30% reduction, region-specific measures including land-use reform and citizen behavioral changes are necessary. Compared with other regions in Japan, Shiga should give priority to a modal shift in transport, efficiency improvements in industry, and photovoltaic energy generation.  相似文献   
384.
Development of plans to restore degraded areas in the Great Lakes   总被引:3,自引:0,他引:3  
The International Joint Commission's Water Quality Board has identified 42 Areas of Concern in the Great Lakes ecosystem where Great Lakes Water Quality Agreement objectives or jurisdictional standards, criteria or guidelines, established to protect uses, have been exceeded and remedial actions are necessary to restore beneficial uses. As a result of the 1985 report of the Water Quality Board, the eight Great Lakes states and the Province of Ontario committed themselves to developing a remedial action plan (RAP) to restore all uses in each Area of Concern within their political boundaries. Each RAP must identify the specific measures necessary to control existing sources of pollution, abate existing contamination (e.g., contaminated sediments), and restore all beneficial uses. Points which must be explicitly addressed in each RAP include: geographic extent of problem, beneficial uses impaired, causes of problems, remedial measures and a schedule for implementation, responsible agencies, and surveillance and monitoring activities that will be used to track effectiveness of remedial actions. The jurisdictions are responsible for developing RAPs, and the International Joint Commission is responsible for evaluating the adequacy of each RAP and tracking progress in restoring beneficial uses.  相似文献   
385.
药物是环境介质中一类新型污染物,多数药物具有手性对映体特性,药物对映体的分离分析是研究对映体水平药物环境行为和效应的前提.采用商品手性柱Chirobiotic#x00AE;V,在反相条件下,对马来酸扑尔敏进行了手性分离,考察了不同流速、柱温、pH值和流动相组成对分离的影响,并优化了色谱条件.结果表明:以含0.1%(体积分数)冰醋酸和0.1%(体积分数)三乙胺的水溶液(TEAA)与四氢呋喃(THF)混合为流动相,在所研究范围内,随着流动相中THF含量的增加、pH值增大和流速增大,马来酸扑尔敏对映体的分离效果降低;柱温影响存在峰值现象,即分离效果随温度的升高先增大后减小.优化得到的拆分条件为:流动相TEAA∶THF为95∶5(V/V),pH值为3,流速为0.3 mL·min~(-1),柱温为15℃.利用分子对接技术模拟万古霉素不同区域与扑尔敏对映体间的相互作用,计算得到了最稳定结合能,据此预测对映体的出峰顺序与实验结果完全一致.初步手性识别机理研究结果表明,引起手性识别的主要作用力为氢键作用.  相似文献   
386.
灾害经济损失概念及产业关联型间接经济损失计量   总被引:19,自引:0,他引:19  
从三个方面拓展了对自然灾害经济的理解,它们是:承灾体,经济损失中的价格与价值,间接经济损失类型。评述了国内迄今提出的关于自然灾害产业关联型间接经济损失的计算方法,同时提出了作者对这一问题的处理,并以中国90年代的水旱灾害为例,计算了这一期间的平均年度产业关联型间接经济损失及经济损失总值。  相似文献   
387.
运用行政法学理论,结合环境管理的特点,对环境行政执法的概念、主体、内容等进行了探讨,并提出了较为全面、系统的执法程序。  相似文献   
388.
A systems approach has been applied to the examination of sustainable development in the coastal zone. This complex system is envisaged as comprising three sub-systems: environment and resources, economic development and society. A sustainability indicator system based on these three sub-systems has been set up to evaluate the nature of development in the coastal zone. The administrative regions of the Municipality of Shanghai and Chong Ming Island (in the Yangtze Estuary) have been selected as two coastal zones in which to demonstrate the feasibility and effectiveness of the approach. The approach indicated that the development process in Shanghai is one of weak sustainability with relatively rapid social and economic development at the cost of environment and resource degradation. In contrast, social and economic development in Chong Ming County has been limited to protect the regional environment and resources indicating a more sustainable approach to development.  相似文献   
389.
This article deals with the development and application of a cartographic database for a synoptic Geographic Information System (GIS). Its purpose is the storage and evaluation of the heterogeneous datasets of the interdisciplinary scientific research program MADAM (Mangrove Dynamics and Management), which aims to develop recommendations for a tailored integrated coastal management scheme for the mangrove ecosystem at Bragança (North Brazil). The article describes the integration of remote sensing data, aerial photographs, as well as point data provided by fieldwork from different scientific fields. Using various innovative processing techniques and different scale-resolution levels, an assessment of temporal–spatial changes of the mangrove peninsula and the adjacent rural socioeconomic impact area, the type of mangrove structure, as well as a land-use cover analyses was undertaken. The definition of the spatial level of detail was found to be a major issue in the development of the GIS, as well as during the processing and analysis procedures. A division between strong and weak patterns in the mangrove ecosystem could be made, which implies different management measures and sets of specific interdisciplinary studies and monitoring at hierarchical scales.  相似文献   
390.
安全伦理学是伦理学的重要基础。安全伦理命题始终存在着道德反省与不反省两种哲学态度,后者长期以来一直占主流,使得安全伦理学的研究滞后,导致其在安全科学学科体系中“空缺”。应当看到,在处理“安全获得与财富获得”的价值关系上,需要建构安全伦理理论,树立科学的安全价值观理论,因而需要制定一套能指导和判断安全活动或行为的道德规范标准。建构安全伦理学,首先要把安全道德作为研究对象;其次根据其特殊的规范性、明显的实践性和具体的专业性等性质特点,提出一种区分安全活动的道德与不道德的原则,并决定安全伦理学的基本问题,为了保存、尊重生命,维护个体的安全权益和增进个体的自由与安全地位平等的社会正义,安全活动应该遵循那些伦理规范;最后确定出该学科的研究方法。  相似文献   
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