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1.
农业生态系统能流和能量分析研究的某些新进展 总被引:8,自引:0,他引:8
对近年来农业生态系统能流和能量分析研究的某些新进展进行了介绍了介绍和评述,重点介绍了H T Odum所创立的能值概念和Giampietro等人提出的生物物理资本概念。对这些新概念在农业生态系统分析中的应用进行了讨论。 相似文献
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本文论述了由我国杰出生态学家马世骏教授首先提出的农业生态工程的概念;综述中国农业生态工程的特征和发展趋势。文中把农业生态工程的概念与一些国家的持续农业的概念进行了比较,提出我国目前发展农业生态工程存在的问题和研究任务,以及一些具体建议。 相似文献
3.
谈谈生态农业的生态设计 总被引:2,自引:0,他引:2
唐德富 《生态与农村环境学报》1988,(3)
生态农业是一种新型农业。生态农业在我国发展很快,生态农业建设已成为我国农业发展的一条希望之路。目前,我国生态农业建设已经进入了生态设计阶段。本文根据生态学和生态经济学原理比较系统地介绍了生态农业生态设计的概念及一些基本内容。 相似文献
4.
吴佐礼 《生态与农村环境学报》1994,(3)
本文就目前广泛应用的农业生态系统能流分析方法及有关概念作了分析,提出了辅助能替代率的概念。建议用辅助能替代率代替能量产投比对农业生态系统进行能流分析。文中还讨论了工业辅助能的计算及其在不同系统间或同一系统不同时段的可比性。 相似文献
5.
人工影响天气对甘肃农业可持续发展的影响 总被引:1,自引:0,他引:1
谢金南 《资源生态环境网络研究动态》1998,9(1):27-30
介绍了人工影响天气的概念、原理和作业方法。在论述了人工影响天气在甘肃省农业可持续发展的作用的基础上,提出以下建议:(1)进一步重视空中水资源的开发;(2)进一步增强人工影响天气作业的有效性;(3)进一步加强对人工影响天气作业的管理。 相似文献
6.
《湖南环境生物职业技术学院学报》2015,(4)
在介绍了目前我国农业污水的来源,主要特征和排放现状的基础上,简述我国农业污水处理技术研究动态,重点对近几年我国农业污水处理技术的研究及应用进展进行阐述,同时对处理技术及工艺优缺点进行了分析.探讨了农业污水处理的难点,处理所面临的问题,提出了在设计和选择农业污水处理技术时应注意的问题,对今后农业污水治理的政策,法规及技术发展的方向提出了建议.表3,参21. 相似文献
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Gerhard Lammel 《Environmental Sciences Europe》2002,14(4):245-253
With the aim of providing results for precautionary environmental politics at an early point in time, a strategy is being sought to optimize the identification of research objects in substance-related environmental research. Both, proven as well as potential substance risks are considered as such. This approach is meant to support pro-active elements in environmental chemistry (as opposited to re-active elements associated with environmental damage). In the atmosphere, substance risks are created by perturbations of functions of the atmosphere and of other natural spheres, as far as atmospheric functions are part of the cause-effect relationships. A complete risk assessment includes exposure and effects analyses, a prerequisite for the latter is the identification of critical effect thresholds (in general: criticalities). However, the state of knowledge in many cases does not allow for a quantitative analysis of the cause-effect relationships. Exposure analysis can be significant for the identification of relevant research objects, because the quantification of the spatial and temporal extent of the potential damage constitutes an important risk category which can be addressed by exposure analysis. Examples for priority issues of substance-related environmental research are given based on combined exposure and effect analyses, as well as on exposure analyses alone. References for the knowledge production process in substance-related environmental science are provided in the field of risk assessment and using the syndrome concept. 相似文献
13.
Interactions between water and land in The Netherlands 总被引:1,自引:0,他引:1
The Netherlands are one of the most densely populated coastal countries in the world and there is only limited space for living,
working, transport and recreation, while there is also the need to preserve and expand valuable natural habitats. In order
to solve many existing and future conflicts of interest, and in order to create ‘added value’, strategies are developed to
optimize the use of water-land systems.
The principle of ‘building with nature’ is applied in order to integrate land in sea and water in land in such a way that
future generations will be able to use coastal resources in a sustainable way, including a minimal effort to maintain the
coastline and the promotion of a multiple-use system.
The concept of Integrated multifunctional sustainable coastal zone development is introduced. This concept deals with a balanced
approach to the lack of space for present and future coastal uses in relation to each other, to the hinterland, and to the
sea. Flexible master plans are developed, taking into account many functions of the coastal zone, and facilitating adaptation
to future developments—e.g. impacts of climate change and relative sea level rise. In this regard increasing the flexibility
of the coastal zone is of vital importance.
Large-scale coastal land reclamations in The Netherlands are dealt with, based on two different principles: (1) polder systems
(low lying land reclamations surrounded and protected by dikes), (2) systems of ‘building with nature’—land reclamation protected
by man-made foreshores, beaches and dunes. In the latter type new flexible dynamic-equilibrium coasts are created for many
functions, while coastal vulnerability is reduced and a flexible coast is developed. 相似文献
14.
Framing the ecosystem concept through a longitudinal study of developments in science and policy 下载免费PDF全文
Filip Aggestam 《Conservation biology》2015,29(4):1052-1064
This paper examines how scientific literature and policy documents frame the ecosystem concept and how these frames have shaped scientific dialogue and policy making over time. This was achieved by developing a frame typology, as a basis for organizing relevant value expressions, to assess how different frames have altered perspectives of the ecosystem concept. The frame typology and analysis is based on a semi‐grounded and longitudinal document analysis of scientific literature and policy documents using the ecosystem concept. Despite changing discourses and public priorities (e.g., cultural constructs of biodiversity) both science and policy documents are characterized by stable value systems that have not changed substantially since the 1930s. These value systems were defined based on ethical principles that delineate 6 core frames: humans first, dual systems, eco‐science, eco‐holism, animals first, and multicentrism. Specific crises (e.g., climate change) and cross‐disciplinary uptake and re‐uptake of, for example, the ecosystem services concept, have brought new perspectives to the forefront of public discourse. These developments triggered changes in the core frames that, rather than being value based, are based on how the ecosystem is conceptualized under fixed value systems and over time. Fourteen subframes were developed to reflect these longitudinal changes. There are as such clear framing effects in both scientific literature and in policy. Ecosystem research is for instance often characterized by unstated value judgments even though the scientific community does not make these explicit. In contrast, policy documents are characterized by clear value expressions but are principally management driven and human centered. 相似文献
15.
孙有成 《生态与农村环境学报》1994,(2)
农业产品因投入劳动和消耗自然界的资源形成价值。农业产品在生产和流通过程中,伴随其本身的价值,还会产生其经济效益。利用生态循环中可以再生的资源,可产生生态经济效益,运用先进的农业技术可产生技术经济效益,流通领域中的供求优势可产生社会经济效益。 相似文献
16.
《Ecological modelling》2005,185(1):65-75
As economic and ecological support systems become more interdependent, new disciplines are needed to “bridge the gap” between human and nature. “Emergy” created by H.T. Odum is a new method for evaluating natural capital and ecosystem services. The “ecological footprint” created by Wackernagel and Rees has been promoted as a policy and planning tool for sustainability. The aim of this paper is to show a modified form of ecological footprint calculation by combining emergy analysis with conventional ecological footprint form of calculations. Our new method starts from the energy flows of a system in calculating ecological footprint and carrying capacity. Through a study of the energy flows, and using the method of emergy analysis, the energy flows of a system are translated into corresponding biological productive units. To demonstrate the mechanics of this new method, we compared our calculations with that of an original calculation of ecological footprint of a regional case. We select Gansu province in western China, as an example for application of our study. In this case the same conclusions were drawn using both methods: that Gansu province runs an ecological deficit. 相似文献
17.
丛枝菌根真菌对内蒙古草原大针茅群落的影响 总被引:2,自引:0,他引:2
使用真菌抑制剂在内蒙古草原开展原位试验,人为创造菌根受抑制和正常两种环境,通过分析菌根侵染率,测定大针茅群落的物种组成、丰富度和多样性等结构指标,分析丛枝菌根真菌对群落结构和净初级生产力的影响。试验结果表明,两种处理群落的菌根侵染率不同,苯菌灵有效地降低了植株的菌根侵染率。丛枝菌根真菌短期内未能对植物群落的物种丰富度、多样性产生影响,未能改变植物群落的结构和净初级生产力。但丛枝菌根真菌的存在,会对植物群落内不同植物种的地上部生物量实现再分配,降低了优势种垄断资源的能力,使群落内物种的生物量和营养元素含量趋于均匀,有利于保护关键种,有利于植被的恢复与重建。因此,研究结论为内蒙古退化草原生态系统的恢复和重建提供了重要的理论依据和参考价值。 相似文献
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Milan Stra
kraba 《Ecological modelling》2001,140(3)
Based on cybernetic categories of natural control mechanisms, four generations of ecosystem models are distinguished: feed-forward, feedback, self-adaptation and self-organization models. The analysis of the natural control mechanisms in aquatic ecosystems suggests that different processes are controlled in different ways, and, although the four mechanisms were identified in historical sequence, they all operate simultaneously. The concept of self-organization of an ecosystem is introduced and specified for a model of an aquatic pelagic ecosystem. The concept of the ecosystem as a multilayer, multigoal and multiechelon hierarchical system with hierarchy of the levels of biological organization is also introduced. 相似文献
19.
Milan Straškraba 《Ecological modelling》1979,6(4):305-321
Based on cybernetic categories of natural control mechanisms, four generations of ecosystem models are distinguished: feed-forward, feedback, self-adaptation and self-organization models. The analysis of the natural control mechanisms in aquatic ecosystems suggests that different processes are controlled in different ways, and, although the four mechanisms were identified in historical sequence, they all operate simultaneously. The concept of self-organization of an ecosystem is introduced and specified for a model of an aquatic pelagic ecosystem. The concept of the ecosystem as a multilayer, multigoal and multiechelon hierarchical system with hierarchy of the levels of biological organization is also introduced. 相似文献
20.
Alexandria M. Frawley 《国际发展与全球生态学杂志》2013,20(3):196-204
The application of capitalist theory and the perception of an autonomous economy have created a range of environmental and social ramifications not addressed via traditional economic reasoning. In order to effectively and efficiently abate sustainability issues, the sustainable development discourse developed evaluation methods such as sustainable development indicators to gauge progress towards sustainability in communities without using traditional cost–benefit methods of analysis. The indicators created in this work are intended to be applied as a method of project evaluation in local community development departments. Using local growth management policy as a basis, these indicators have been designed to show how a development project contributes to policy goals that relate to all three dimensions of sustainability: environmental, economic, and socio-economic. 相似文献