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911.
912.
913.
Uta Berger Marion Glaser Boris Koch Gesche Krause Rubén Lara Ulrich Saint-Paul Dirk Schories Matthias Wolff 《Journal of Coastal Conservation》1999,5(2):125-134
The main objective of the MADAM project (Mangrove Dynamics and Management) is to generate the scientific basis enabling the
sustainable stewardship of the resources of the Caeté mangrove estuary in Northeast Brazil in the sense of integrated coastal
(zone) management. To achieve this, it is necessary to acquire in-depth knowledge of natural processes as well as of the relevant
institutional, cultural, economic, social and political dynamics. Causal linkages within the ecosystem, as well as between
ecosystem, economy and society, are analysed and explained via dynamic and trophic modelling. Scenario construction is intended
to forecast the effects of acute or chronic interference on utilized resources, and to answer wider, management-related questions
(e.g. restoration of destroyed areas, utilization potential for aquaculture). This paper describes the project strategy as
developed and modified in the context of research results from the initial 2-yr project phase. It is argued that a continuous
discussion process is essential to assess the validity of the strategies formulated at the beginning of a medium-time project,
particularly if the project is of interdisciplinary nature. 相似文献
914.
常德市土地利用结构优化研究 总被引:7,自引:1,他引:6
通过对常德市土地资源的基本特征,土地利用结构现状特点及存在的主要问题的分析,提出了优化常德市土地利用结构的对策。 相似文献
915.
The excessive application of fertilizer and pesticides in grain production in China has posed a threat to the environrnental sustainability of agricultural production. One of the major reasons of the increasing usage of chemical inputs by farmers is their trying to reach higher yields, especially in absence of adequate public inputs, such as development and extension of appropriate technology and necessary production infrastructure, etc. Based on the cropspecific data of the past 20 years, this paper examines how the public investments in agricultural researches could impact on the reduction of farmers' private material inputs of major grain crops in China. It manifests that the increased investments in public sector, especially in agricultural researches, is a favorable and effective way to reduce farmers' private material inputs and should be given a priority consideration in the policy emendation to increase yields and improve production sustainability. 相似文献
916.
Evelyn B. Pluhar 《Journal of Agricultural and Environmental Ethics》1988,1(3):211-224
Professor Hugh Lehman has recently argued that the rights view, according to which nonhuman animals have a prima facie right to life, is compatible with the killing of animals in many circumstances, including killing for food, research, or product-testing purposes. His principle argument is an appeal to life-boat cases, in which certain lives should be sacrificed rather than others because the latter would allegedly be made worse-off by death than the former. I argue that this reasoning would apply to so-called inferior humans just as much as to animals, and that this appeal is unsuccessful in any case. I distinguish two versions of the rights view: the equal and the unequal rights views. Although the unequal rights view, unlike the equal rights view, would sanction the killing of animals (and some humans) for food under severely restricted circumstances, neither rights view sanctions the raising of animals for their meat. Moreover, neither rights view would sanction the killing of animals for research or product-testing purposes. I conclude with a brief discussion of the merits of phasing out the meat production industry. 相似文献
917.
为完善安全科学原理体系,指导安全科学原理研究工作的开展,从方法论角度探讨安全科学原理的研究。结合安全科学、安全科学方法论与方法学,给出安全科学原理及安全科学原理研究方法论的定义,并从方法的角度对安全科学原理进行分类,阐明不同存在状态的安全原理的研究取向,确定安全科学原理的结构三要素。提出以安全现象-安全规律-安全原理为发展主线的第1类未知安全科学原理的一般构建步骤,以及以并列-比较-假设-检验为主线的第2类未知安全科学原理构建步骤,并建立安全科学原理动态研究的范式体系。研究结果使安全科学原理研究的层次思路系统化,并有益于指导安全原理研究工作的进行。 相似文献
918.
919.
David Gibbon 《Disasters》1987,11(1):53-58
It is the principal proposition of this paper that formal agricultural research, and its supporting policies and planning, has not responded adequately to the special situation that exists in semi-arid Africa. In many cases the transfer of research approaches based on temperate and more humid tropical experience has contributed to greater instability and the growing environmental crisis. Radically different research structures, objectives, methods and expectations are necessary to contribute to the redevelopment of long term regenerative systems of production that will provide the short and long term needs of the people who live in the semi-arid regions and at the same time protect these environments. 相似文献
920.
Farmers attempting to subsist in tropical uplands often rely upon unsustainable resource use practices that lead to soil erosion, declining crop yields, and a loss of soil productivity capacity. Other uses of tropical uplands, including logging and conversion of forest to rangelands, have similar results. The undesirable effects of these actions are felt on-site, at the watershed level, and even nationally. Ecological cause-effect relationships are poorly understood, and few examples exist of the successful integration of ecological knowledge with upland development. It is hypothesized that recent results of ecological research could be applied to uplands management so that stable sustainable systems of human use may be established. A second hypothesis is that statistically reliable data can be obtained from experiments in upland situations, although natural variations of soils, weather, and vegetation are great. To test these hypotheses, research involving multinational collaboration among American and Southeast Asian scientists has begun. The objective of the work is to provide credible quantitative information to help policy and decision makers and resident farmers to plan and implement improved practices based on ecological principles.Some findings to date include:
相似文献
1. | Ecological principles are difficult to relate to the practical context of upland agroecosystems. Indeed, the null hypothesis is necessary for planning experiments and demonstrations. |
2. | The signal-to-noise ratio in these field experiments is low, and the detection of changes due to human intervention in soil erosion, nutrient movement, and plant productivity is difficult. |
3. | Obstacles to field research in developing countries include logistic, cultural, political, and institutional factors. It is essential that local land managers participate from the start with scientific researchers in designing experiments. |
4. | Planned collaboration among academic and government scientists facilitates design of relevant research and the implementation of results. |
5. | The idea of ecologically based management has been well received by researchers and government officials in Asia. There is little argument with the logic of the approach. |
6. | Pressures for quick responses to urgent problems in the uplands conflict with the need for careful, long-term, statistically valid scientific research. |
7. | Ecological principles are vaguely understood and poorly articulated in the scientific literature. The transfer and application of ecological science to the developing world would be enhanced by clearer statements of principles. |