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991.
长江三角洲及其附近地区两千年来水灾的研究 总被引:6,自引:1,他引:5
通过对长江三角洲及其附近地区两千年来水灾生成频率和强度的分析。认为两晋、南北朝时期和南宋、元、明、清时期是两千年来本区的主要水灾期。对照两千年来中国东部气候变化、海面升降与长江口河道变迁关系,认为在本区水灾生成事件中,气候因素起着主导控制作用。当然,人类活动对本区水灾生成的影响也不容忽视。本地区近百年来的旱涝灾害规律可用非线性科学的方法进行研究,旱涝灾害的准60年、准35年和准11年的长周期变化与地球自转速度、地极移动和太阳黑子活动的3个周期变化基本一致。本地区气候系统的行为具有混沌特征。这是线性逼近和周期叠加预报方法难以得出灾害预报正确结果的原因,但气候系统半个月的确定性预测可以实现。 相似文献
992.
This paper describes an application of multiple criteria analysis (MCA) in assessing criteria and indicators adapted for a
particular forest management unit. The methods include: ranking, rating, and pairwise comparisons. These methods were used
in a participatory decision-making environment where a team representing various stakeholders and professionals used their
expert opinions and judgements in assessing different criteria and indicators (C&I) on the one hand, and how suitable and
applicable they are to a forest management unit on the other. A forest concession located in Kalimantan, Indonesia, was used
as the site for the case study. Results from the study show that the multicriteria methods are effective tools that can be
used as structured decision aids to evaluate, prioritize, and select sets of C&I for a particular forest management unit.
Ranking and rating approaches can be used as a screening tool to develop an initial list of C&I. Pairwise comparison, on the
other hand, can be used as a finer filter to further reduce the list. In addition to using these three MCA methods, the study
also examines two commonly used group decision-making techniques, the Delphi method and the nominal group technique. Feedback
received from the participants indicates that the methods are transparent, easy to implement, and provide a convenient environment
for participatory decision-making. 相似文献
993.
Integrated Resource Management: Moving from Rhetoric to Practice in Australian Agriculture 总被引:1,自引:0,他引:1
/ Implementing the concept of sustainability through integrated approaches to natural resource management poses enormous challenges for both the rural communities and government agencies concerned. This paper reviews the underlying rhetoric of sustainable agricultural systems and the integrated resource management paradigm and identifies some of the challenges being experienced in translating this rhetoric into practice. A relatively recently implemented community-based integrated catchment management (ICM) process in a rural community in northeast Australia is examined in terms of some of the lessons learned that may be relevant to other similar integrated resource management (IRM) processes. It reveals a pragmatic, opportunistic, and evolving implementation process based on adaptive learning rather than a more traditional "rational" planning approach. Some essential characteristics of a community-based IRM process are identified, including fostering communication; providing a structure that fosters cooperation and facilities coordination among community, industry, and government agencies; the integration of IRM principles into local government planning schemes; and an emergent strategic approach to IRM program implementation. We conclude by identifying some essential characteristics of an IRM process that can assist a community to adapt to, and manage change for, sustainable resource use. 相似文献
994.
This paper looks at the rainfall and streamflow patterns over two distinct time periods, i.e., 1950–1970 and 1971–1991 within the two most prominent catchments in the Volta river system – White Volta and the Oti basins. The first period (1950–1970) represents relatively vegetated catchments and low population whilst the latter (1971–1990) represents intense land use practices resulting from increased population that have severely degraded the environment. These two catchments are among the most significant contributors to the Volta lake. The Volta lake, which was formed between 1962 and 1966 in Ghana and created primarily for hydroelectric power generation, will probably be one of the greatest man-made lakes for a long time. It produces 912MW of electricity at its maximum operating capacity. Recently, there have been declines in the lake levels resulting most probably from inadequate rainfall and/or runoff from the river catchments that feed the lake. Comparisons of runoffs for the two time periods show reductions in mean streamflows of 32.5% at Saboba on the Oti and 23.1% at Nawuni on the White Volta. 相似文献
995.
It is now part of received wisdom that humanitarian assistance in conflict and post-conflict situations may be ineffective or even counterproductive in the absence of an informed understanding of the broader political context in which so-called 'complex political emergencies' (CPEs) occur. Though recognising that specific cases have to be understood in their own terms, this article offers a framework for incorporating political analysis in policy design. It is based on a programme of research on a number of countries in Africa and Asia over the last four years. It argues that the starting-point should be an analysis of crises of authority within contemporary nation-states which convert conflict (a feature of all political systems) into violent conflict; of how such conflict may in turn generate more problems for, or even destroy, the state; of the deep-rooted political, institutional and developmental legacies of political violence; and of the difficulties that complicate the restoration of legitimate and effective systems of governance after the 'termination' of conflict. It then lists a series of questions which such an analysis would need to ask--less in order to provide a comprehensive check-list than to uncover underlying political processes and links. It is hoped these may be used not only to understand the political dynamics of emergencies, but also to identify what kinds of policy action should and should not be given priority by practitioners. 相似文献
996.
农村污染防治工作已迫在眉睫 总被引:1,自引:0,他引:1
针对目前农村经济发展过程中出现的主要环境问题,结合农村的实际情况,提出了解决农村环境污染问题的几项措施。并着重分析了规模化畜禽养殖业中的环境污染问题,提出了综合防治对策。 相似文献
997.
刘少宁 《中国环境管理干部学院学报》2007,17(1):4-6
最近美国离境外包经济发展很快,并引发继第一次产业革命(即工业革命)和第二次产业革命(即服务业超过制造业)之后的第三次产业革命,进而美国大批制造业向国外转移。这对我国承接制造业的产业转移是重大机遇,但同时也会遇到污染、能源转移的问题。建议我国抓住机遇,保持和发挥人力资源优势,迅速发展制造业,同时积极应对环境影响,分类管理,严格执法。 相似文献
998.
岳卫峰 《中国环境管理干部学院学报》2007,17(2):41-42,46
经营者的安全保障义务无论在理论界还是在实践中都受到大家的关注。本文对经营者之所以承担安全保障义务的法理基础进行论述,陈述了传统民法理论和我国目前学界对此的看法,探讨了经营者的安全保障义务的性质和具体内容。 相似文献
999.
1000.
金沙江流域是我国13大水电基地中水能资源蕴涵量最大的地区,但开发率相对较低。在介绍金沙江流域丰富的水电资源及其开发现状的基础上,分析了加快金沙江水电开发的可能条件和重要意义;针对开发中存在的主要问题,根据市场经济原则和具体情况提出了对策和建议。 相似文献