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611.
Sustainable development and the definition of indicators to assess progress towards sustainability have become a high priority in scientific research and on policy agendas. In this paper, we propose a consistent and comprehensive framework of principles, criteria and indicators (PC&I) for sustainability assessment of agricultural systems, referred to as the Sustainability Assessment of Farming and the Environment (SAFE) framework. In addition we formulate consistent and objective approaches for indicator identification and selection. The framework is designed for three spatial levels: the parcel level, the farm level and a higher spatial level that can be the landscape, the region or the state. The SAFE framework is hierarchical as it is composed of principles, criteria, indicators and reference values in a structured way. Principles are related to the multiple functions of the agro-ecosystem, which go clearly beyond the production function alone. The multifunctional character of the agro-ecosystem encompasses the three pillars of sustainability: the environmental, economic and social pillars. Indicators and reference values are the end-products of the framework. They are the operational tools that are used for evaluating the sustainability of the agro-ecosystems. The proposed analytical framework is not intended to find a common solution for sustainability in agriculture as a whole, but to serve as an assessment tool for the identification, the development and the evaluation of agricultural production systems, techniques and policies.  相似文献   
612.
海洋生态调控智能决策支持系统(IDSSMER)是建立在海洋生态系统动力学原理与控制论方法基础上,以计算机科学技术为主,综合系统科学、管理科学以及海洋生态学的理论和方法的人机交互系统,旨在为决策者在协调资源与环境的生态关系、探索海洋生物资源可持续发展的生态调控对策与可行途径等方面提供一个良好的支持工具。给出IDSSMER的数据库系统、模型库系统、方法库系统及知识库系统,具有信息服务、科学计算和决策咨询的功能,这种四库三功能结构,以实规定量计算与定性推理有机地结合。最后构迄了基于数据库的知识库以及采用双向推理策略的海洋生态知识库系统结构。  相似文献   
613.
Predicting the logarithm of hexadecane/air partition coefficient (L) for organic compounds is crucial for understanding the environmental behavior and fate of organic compounds and developing prediction models with polyparameter linear free energy relationships. Herein, two quantitative structure activity relationship (QSAR) models were developed with 1272 L values for the organic compounds by using multiple linear regression (MLR) and support vector machine (SVM) algorithms. On the basis of the OECD principles, the goodness of fit, robustness and predictive ability for the developed models were evaluated. The SVM model was first developed, and the predictive capability for the SVM model is slightly better than that for the MLR model. The applicability domain (AD) of these two models has been extended to include more kinds of emerging pollutants, i.e., oraganosilicon compounds. The developed QSAR models can be used for predicting L values of various organic compounds. The van der Waals interactions between the organic compound and the hexadecane have a significant effect on the L value of the compound. These in silico models developed in current study can provide an alternative to experimental method for high-throughput obtaining L values of organic compounds.  相似文献   
614.
江苏省突发性环境污染事故应急监测支持系统的建立   总被引:4,自引:0,他引:4  
张涛  钱江  严刚 《云南环境科学》2005,24(Z1):231-232
介绍了江苏省突发性环境污染事故应急监测支持系统,以及该系统的风险源管理子系统、组织保障子系统和技术支持子系统模块的功能意义,为省级应急监测支持系统的建立提供参考和帮助。  相似文献   
615.
OntheecologyofvectorsFernandoDiasdeAvilaPiresDepartmentofTropicalMedicine,InstitutoOswaldoCruz,21045900RiodeJaneir,BrazilAb...  相似文献   
616.
煤炭资源型城市循环经济发展研究   总被引:1,自引:0,他引:1  
黑龙江省的鹤岗﹑双鸭山﹑七台河﹑鸡西是全国著名的资源型城市,这些城市为全国提供了大量的煤炭资源,为经济的发展做出了很大的贡献,当前在大力发展循环经济方面,这些城市作了许多探索和实践,取得了许多宝贵的经验,煤炭资源型城市发展循环经济大有可为,但从其发展情况来看,现在仍存在着一些问题阻碍和制约了循环经济的发展,我们通过对这四个煤炭资源型城市发展循环经济的现状和存在问题的调研,提出了资源型城市循环经济发展的对策和建议.  相似文献   
617.
针对临海航天发射场设施设备金属结构腐蚀严重的问题,基于金属腐蚀机理,对发射场设施设备的差异性腐蚀损伤进行了统计和梳理,得出腐蚀成因,并提出腐蚀控制策略和研究方向的建议,为进一步提升我国航天发射场维修保障能力提供理论和技术支撑.  相似文献   
618.
On the basis of a statistical analysis of the papers published in Ecological Modelling from 1975 to 1996, it has been attempted to examine the development of the field of ecological modelling and systems ecology. It was found that while models of aquatic ecosystems and management issues were more in focus in the 1970s, terresterial ecosystems and ecological theory have gained attention during the 1990s. Interest in ecotoxicological models seems to have increased only slightly during the entire period. It is interesting that financial support for the area of ecological modelling and systems ecology is closely related to the number of publications, which can be seen from the number of papers published by various countries in the journal. Hopefully, this clear message can be used to show to politicians that these relationships are real.  相似文献   
619.
抗砷载体的构建及在氧化亚铁硫杆菌中的表达   总被引:5,自引:2,他引:5  
利用DNA体外重组技术,将抗砷质粒pUM3经HindⅢ酶切后得到的4.3kb抗砷片段克隆到有广泛寄主的IncQ质粒pJRD215的HindⅢ位点上,构建了一个新的抗砷质粒pSDX3。砷抗性研究表明,在大肠杆菌中,pSDX3的抗砷水平与pUM3相近。将pSDX3通过接合的方式引入氧化亚铁硫杆菌Tf-59中并得到了表达,与对照相比,含质粒pSDX3的Tf-59抗砷水平有了很大的提高。  相似文献   
620.
Abstract:  Conservation management is becoming increasingly resource intensive as threats to biodiversity grow through habitat destruction, habitat disturbance, and overexploitation. To achieve successful conservation and sustainable use of natural resources, we need to scientifically evaluate the effectiveness of conservation interventions and provide an efficient framework through which scientific evidence can be used to support decision making in policy and practice. We conducted the first formal assessment of the extent to which scientific evidence is used in conservation management through a questionnaire survey and follow-up interviews of compilers of protected-area management plans from major conservation organizations within the United Kingdom and Australia. Our survey results show that scientific information is not being used systematically to support decision making largely because it is not easily accessible to decision makers. This, in combination with limited monitoring and evaluation of effectiveness of management interventions, results in the majority of decisions being based on experience rather than on evidence. To address this problem we propose using an evidence-based framework adapted from that used in the health services and explain how we are currently putting an equivalent framework into practice by establishing review and dissemination units to serve the conservation sector.  相似文献   
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