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781.
In revegetation trials on disturbed riverbank sites in the Montréal region (Québec, Canada), an analysis of their structure by means of their biotic and abiotic components was undertaken. Vegetation sampling and physical surveys, together with soil analyses of 62 stands, grouped in 20 sectors, were carried out in the summer of 1986. The statistical analyses of biotic and abiotic data were executed in parallel by a hierarchical agglomerative cluster analysis (arithmetic average clustering) and by an ordination in reduced space (principal coordinate analysis). The species colonizing these riverbanks are, for the most part, ruderals from the Montréal region, of which more than 50% are introduced species. The pioneering communities characterizing these artificial habitats have had very little impact on the physical conditions of their environment; therefore, the ordination on the plant communities proves to be strongly correlated to the ordination stemming from the abiotic components. The statistical analysis retains the original sectors, underlining the fact that each human intervention generally results in the creation of a particular ecological situation. 相似文献
782.
王如松 《中国人口.资源与环境》1997,7(3):11-14
本文提出了社会发展综合实验区建设的实质就是协调好人口、资源与环境间的生态关系,为了促进社会—经济—自然复合生态系统的持续发展,探讨了科技引导实验区生态建设的途径。 相似文献
783.
In order to develop small islands, not only must a vital agricultural system be maintained, but the range of opportunities
for tourism must be increased with respect to both the seaside and the environmental features of the rural landscape. As an
alternative to the traditional and economically declining ones, many innovative production processes can be identified, but
their success depends on their interaction with the physical, biological, economic and social environment. In order to identify
the main nodes and the most critical interactions, so as to increase the probability of success of a new productive process,
a methodological approach based on the science of complexity is proposed for the cultivation of capers (Capparis spinosa L.) on the island of Pantelleria. The methodology encompasses the identification of actors and factors involved. the quantitative
evaluation of their interactions with the different stages of the productive process, and a quasiquantitative evaluation of
the probability that the particular action will be performed successfully.
The study of “traditional,” “modernized,” and “modernized-sustainable” processes, shows that the modernized-sustainable process
offers mutually reinforcing opportunities in terms of an integrated development of high-quality agricultural products and
the enhancement of environmental features, in conjunction with high-efficiency production techniques, in conjunction with
high-efficiency production techniques, in a way that suits the development of Pantelleria. There is a high probability of
failure, however, as a result of the large number of critical factors. Nevertheless, the present study indicates which activities
will enhance the probability of successful innovation in the production process. 相似文献
784.
Stephen R. Gliessman 《Environmental management》1992,16(6):681-689
Agroecology is the application of ecological concepts and principles to the design and management of sustainable agricultural
systems. An agroecological approach to agriculture has special importance in the humid tropics where agricultural development
and the preservation of tropical forests are most often in direct conflict. It is proposed that a more sustainable approach
to development is needed, where agroecosystems depend on low external inputs, function more on the use of locally available
and renewable resources, have benign impacts on the environment, and are based on the knowledge and culture of the local inhabitants.
Examples of traditional agroecosystem management in Mesoamerica that can provide this basis are presented. The preservation
of both biological and cultural diversity are integral to the long-term sustainable management of natural resources in the
tropics. 相似文献
785.
The ecological systems of Earth are subjected to a wide array of environmental stresses resulting from human activities. The
development of appropriate environmental protection and management policies and the appropriate allocation of resources across
environmental stresses require a systematic evaluation of relative risks. The data and methodologies for comprehensive ecological
risk assessment do not exist, yet we do have considerable understanding of econological stress-response relationships. A methodology
is presented to utilize present knowledge for assignment of relative risks to ecological systems and human welfare from anthropogenic
stresses. The resultant priorities, developed for the US Environmental Protection Agency's (EPA) relative risk reduction project,
highlight global climate change, habitat alteration, stratospheric ozone depletion, and species depletion as the highest environmental
risks, significantly diverging from the present emphasis by EPA and the public on toxic chemical issues. Enhanced attention
to ecological issues by EPA and development of ecological risk assessment methodologies that value ecological and economic
issues equitably are key recommendations. 相似文献
786.
Arthropod communities in pear are conceptualized as hierarchically organized systems in which several levels of organization
or subsystems can be recognized between the population level and the community as a whole. An individual pear tree is taken
to be the community habitat with arthropod subcommunities developing on leaf, fruit, and wood subcommunity habitats. Each
subcommunity is composed of trophically organized systems of populations. Each system of populations is comprised of a functional
group or guild of phytophagous arthropods that use the habitat primarily for feeding but also for overwintering or egg deposition,
and associated groups of specialized predators, parasitoids, and hyperparasitoids. Several species move from one subcommunity
to another during the course of community development and thus integrate community subsystems.
Community development or change in organization through time is conceptualized as being jointly determined by the development
of the habitat and the organization of the species pool. The influence of habitat development on community development within
a species pool is emphasized in this research. Seasonal habitat development is expressed as change in the kinds and biomasses
of developmental states of wood, leaf, and fruit subcommunity habitats. These changes are accompanied by changes in the kinds,
biomasses, and distributions of associated community subsystems. 相似文献
787.
Stephen R. Dovers 《Environmental management》1990,14(3):297-305
This article examines the concept of sustainability (sustainable development, sustainable societies) with a view to providing
a means of considering the idea in such a way as to be more useful to concerns of policy. A brief background is given, covering
the historical development of the concept, the constituent ecological and social concerns that lie behind it, and some aspects
of the sustainability debate in Australia. Some attributes of a sustainable future, as evident from the literature, are listed.
The value base of the concept is recognized, and the correct place for sustainability concerns is identified within a simple
policy-making model. The complexity of such a model in the real world is explored using a list of thecontexts of sustainability, illustrated with examples from Australian natural resource management.
Finally, the more dynamic and flexible nature of patterns of production and consumption in more sustainable societies is recognized
and explained, as are two guiding directives to be applied in the search for models which display characteristics of sustainability. 相似文献
788.
Stanley A. Temple 《Environmental management》1996,20(6):873-878
The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) Everything is interconnected (and should usually stay that way), and (2) We can never do merely one thing. The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones. 相似文献
789.
重庆高新区可持续发展水平评价与对策研究 总被引:2,自引:0,他引:2
提出了建立重庆高新区可持续发展评价指标体系的6项基本原则,从经济高效、社会文明、环境舒适(ESE)3方面设计了包括3个高层指标、8个中层指标、45个单项指标的指标体系。采用特尔斐法、层次分析法和线性加权法,对评价指数进行了量化计算和整合,据此评价重庆高新区的可持续发展水平,并对照发展性质相似的苏州高新区、深圳高新区,指出重庆高新区在发展中存在的问题,并提出可持续发展的若干对策。 相似文献
790.
自然保护区生态旅游开发及保护规划探讨——以武夷山自然保护区为例 总被引:3,自引:0,他引:3
对自然保护区生态旅游开发意义和特点进行阐述,并以武夷山自然保护区为例,探讨如何制订自然保护区生态旅游保护规划,提出管理监控的内容和方法。 相似文献