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21.
Weather variability poses numerous risks to agricultural communities, yet farmers may be able to reduce some of these risks by adapting their cropping practices to better suit changes in weather. However, not all farmers respond to weather variability in the same way. To better identify the causes and consequences of this heterogeneous decision-making, we develop a framework that identifies (1) which socio-economic and biophysical factors are associated with heterogeneous cropping decisions in response to weather variability and (2) which cropping strategies are the most adaptive, considering economic outcomes (e.g., yields and profits). This framework aims to understand how, why, and how effectively farmers adapt to current weather variability; these findings, in turn, may contribute to a more mechanistic and predictive understanding of individual-level adaptation to future climate variability and change. To illustrate this framework, we assessed how 779 farmers responded to delayed monsoon onset in fifteen villages in Gujarat, India during the 2011 growing season, when the monsoon onset was delayed by three weeks. We found that farmers adopted a variety of strategies to cope with delayed monsoon onset, including increasing irrigation use, switching to more drought-tolerant crops, and/or delaying sowing. We found that farmers’ access to and choice of strategies varied with their assets, irrigation access, perceptions of weather, and risk aversion. Richer farmers with more irrigation access used high levels of irrigation, and this strategy was associated with the highest yields in our survey sample. Poorer farmers with less secure access to irrigation were more likely to push back planting dates or switch crop type, and economic data suggest that these strategies were beneficial for those who did not have secure access to irrigation. Interestingly, after controlling for assets and irrigation access, we found that cognitive factors, such as beliefs that the monsoon onset date had changed over the last 20 years or risk aversion, were associated with increased adaptation. Our framework illustrates the importance of considering the complexity and heterogeneity of individual decision-making when conducting climate impact assessments or when developing policies to enhance the adaptive capacity of local communities to future climate variability and change.  相似文献   
22.
本文深入分析了上海规划和国土资源管理工作中决策权、执行权、监督权相互分离的重大意义,从理论基础、实践基础、技术条件三个方面论述了上海规划和国土资源行业实施决策权、执行权、监督权相互分离的可行性,重点介绍了上海决策权、执行权、监督权合理配置及运用的初步实践,同时也展望了行政三权分离的发展态势和前景。  相似文献   
23.
Coastal zones are characterized by large concentrations of population, unique and vital ecosystems, and many industrial and other economic activities on land and at sea. The many and diverse activities result in different types of conflicts of use and access to resources in coastal areas. This calls for integrated management of coastal zones. However, successful integrated coastal management must be supported by reliable data and information that will lead to informed decision-making and planning. The International Oceanographic Data and Information Exchange (IODE) network which is a project of the Intergovernmental Oceanographic Commission (IOC) of UNESCO is playing a key role in capacity building for ocean and coastal data and information management in Africa. Currently, about 25 data and information centers have been established in coastal African countries through these efforts. These data and information centers should support effective management of coastal zones.  相似文献   
24.
Zarina Patel 《Geoforum》2006,37(5):682-694
The reshaping of South African cities is being guided by policies aiming to build socially and environmentally just communities. Despite widespread commitment to this goal, there is little consensus on what it means and how it should and could translate into practice. The paper shows that despite the emphasis on environmental justice and building sustainable communities in policy, the institutional context for implementation (including expert driven and deliberative approaches) do not always deliver on this mandate. Consequently, policy outcomes do not reflect those of the communities and households it is meant to serve, raising challenging moral and ethical questions for institutions involved in environmental governance. This paper shows how the institutional context of environmental assessment combined with the role played by the values held by environmental practitioners charged with influencing decision-making result in the perpetuation of environmental injustices. The lack of a clearly defined profession and professional body, reflecting a diversity of values, debating, regulating, defining and defending a set of principles to guide decision-making in cities is identified as a possible reason for the lack of congruence between the values reflected in policy with those held by the communities these interventions are intended to serve. The resulting value added by sustainable cities interventions in the light of this mismatch is therefore questionable, raising challenges regarding international calls for local action as well as an increasing policy focus in South Africa on the local level as the agent of political and spatial transformation of cities.  相似文献   
25.
Abidemi R. Asiyanbola   《Geoforum》2006,37(6):1059-1065
The paper examines women’s involvement in residential location/relocation decision-making among tenants in Ibadan, Nigeria. The data used in the paper is from a larger cross-sectional survey of 721 households on gender and housing in Ibadan, Nigeria. The analysis in the paper focused on 365 subgroup of households that are tenants in the sample survey. Analysis of variance (ANOVA), correlation and simple statistical techniques such as frequencies and percentages were used to analyse the data. The result shows that generally there is low involvement of women in residential location/relocation decision-making. There is significant intra-urban variation in the involvement of women in residential location/relocation decision-making. Significant relationships are found between the level of women involvement in residential location/relocation decision-making and their educational level, occupation, and marital status. In addition, significant relationships are found between cultural and social support variables and involvement of women in residential location/relocation decisions. These results suggest that female empowerment and greater involvement in decision-making could be greatly enhanced by improved access of women to education, employment, the provision of good and reliable social support facilities and a reorientation of women’s view about responsibility for household housing provision.  相似文献   
26.
A grey fuzzy optimization model is developed for water quality management of river system to address uncertainty involved in fixing the membership functions for different goals of Pollution Control Agency (PCA) and dischargers. The present model, Grey Fuzzy Waste Load Allocation Model (GFWLAM), has the capability to incorporate the conflicting goals of PCA and dischargers in a deterministic framework. The imprecision associated with specifying the water quality criteria and fractional removal levels are modeled in a fuzzy mathematical framework. To address the imprecision in fixing the lower and upper bounds of membership functions, the membership functions themselves are treated as fuzzy in the model and the membership parameters are expressed as interval grey numbers, a closed and bounded interval with known lower and upper bounds but unknown distribution information. The model provides flexibility for PCA and dischargers to specify their aspirations independently, as the membership parameters for different membership functions, specified for different imprecise goals are interval grey numbers in place of a deterministic real number. In the final solution optimal fractional removal levels of the pollutants are obtained in the form of interval grey numbers. This enhances the flexibility and applicability in decision-making, as the decision-maker gets a range of optimal solutions for fixing the final decision scheme considering technical and economic feasibility of the pollutant treatment levels. Application of the GFWLAM is illustrated with case study of the Tunga–Bhadra river system in India.  相似文献   
27.
This paper develops a new method for decision-making under uncertainty. The method, Bayesian Programming (BP), addresses a class of two-stage decision problems with features that are common in environmental and water resources. BP is applicable to two-stage combinatorial problems characterized by uncertainty in unobservable parameters, only some of which is resolved upon observation of the outcome of the first-stage decision. The framework also naturally accommodates stochastic behavior, which has the effect of impeding uncertainty resolution. With the incorporation of systematic methods for decision search and Monte Carlo methods for Bayesian analysis, BP addresses limitations of other decision-analytic approaches for this class of problems, including conventional decision tree analysis and stochastic programming. The methodology is demonstrated with an illustrative problem of water quality pollution control. Its effectiveness for this problem is compared to alternative approaches, including a single-stage model in which expected costs are minimized and a deterministic model in which uncertain parameters are replaced by their mean values. A new term, the expected value of including uncertainty resolution, or EVIUR, is introduced and evaluated for the illustrative problem. It is a measure of the worth of incorporating the experimental value of decisions into an optimal decision-making framework. For the illustrative problem, the two-stage adaptive management framework extracted up to approximately 50% of the gains of perfect information. The strength and limitations of the method are discussed and conclusions are presented.  相似文献   
28.
A disaster risk management performance index   总被引:2,自引:4,他引:2  
The Risk Management Index, RMI, proposed in this paper, brings together a group of indicators that measure risk management performance and effectiveness. These indicators reflect the organizational, development, capacity and institutional actions taken to reduce vulnerability and losses in a given area, to prepare for crisis and to recover efficiently from disasters. This index is designed to assess risk management performance. It provides a quantitative measure of management based on predefined qualitative targets or benchmarks that risk management efforts should aim to achieve. The design of the RMI involved establishing a scale of achievement levels or determining the distance between current conditions and an objective threshold or conditions in a reference country, sub-national region, or city. The proposed RMI is constructed by quantifying four public policies, each of which is described by six indicators. The mentioned policies include the identification of risk, risk reduction, disaster management, and governance and financial protection. Risk identification comprises the individual perception, social representation and objective assessment; risk reduction involves the prevention and mitigation; disaster management comprises response and recovery; and, governance and financial protection policy is related to institutionalization and risk transfer. Results at the urban, national and sub-national levels, which illustrate the application of the RMI in those scales, are finally given.  相似文献   
29.
程少华 《极地研究》1992,4(3):58-72
现代南极研究需要现代信息技术的支持。开发利用信息资源 ,强化信息导向的作用 ,是南极领域自身建设的科学思想基础。本文以现代信息技术为经 ,以现代南极研究为纬 ,从软科学和系统科学的角度 ,宏观地俯瞰了南极研究的现在与未来 ,从不同侧面阐述了信息技术对南极研究的支持作用 ,强调了全方位、大科学化的重要性。南极研究作为最能体现国际合作的特殊领域 ,在开拓南极的科学独特性和南极的全球作用两大核心课题时 ,势必从各个层次上系统地应用现代信息技术 ,为参与全球计划的各大尺度问题的研究提供必要的支持。在我国的南极事业中 ,如何造就一个与国际南极研究同步的开放环境 ,加速信息资源的开发利用并能以有效、系统、经济、合理的方式进行 ,是时代赋予的机会 ,也是面临的新挑战 ,更是发展的必然。建立计算机化的南极信息系统是实现决策和管理科学化 ;增强南极活动中的运营能力 ;提高科研水平、加快科研进程的必要途径 ,是加入国际南极信息网络的前提与基础 ,也是全面促进和积极推动现代南极研究深入发展的重要环节。这项综合性的社会技术系统工程的实现 ,需要一个不断深化完善和动态发展的持续过程。  相似文献   
30.
During the last decade, devolution of responsibilities of fisheries management has increasingly become an issue in the political debate. The CEC and national governments have expressed an interest in sharing responsibilities for fisheries management with stakeholders. This article investigates the dynamics and constraints of the devolution process in general and in relation to Danish demersal fisheries by answering the following questions: What are the important factors to consider with respect to sharing responsibilities in fisheries management; how can this delegation and/or devolution of responsibilities be institutionalised? And what kind of decisions should be delegated to stakeholders and to whom?  相似文献   
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