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621.
A. S. Tret’yakova 《Russian Journal of Ecology》2006,37(2):97-102
The data on the biological diversity, bioecological features, and geographic variations of segetal plants in the Middle Urals are presented for the first time. It has been shown that apophytic and anthropophytic groups are equally represented among them. Each group is characterized, and the phytocoenotic activity of segetal plants is considered. 相似文献
622.
Industrial ecology: engineered representation of sustainability 总被引:1,自引:0,他引:1
Industrial ecology is a relatively new field of research and academic study and is well established in North America and in
several Asian countries. However, it has not yet received the attention it deserves in some other important parts of the industrialized
world, including Germany. This paper may contribute to a better appreciation of industrial ecology as a tool in the process
of sustainable development of economies, social systems, and of aquatic and terrestrial biotopes under the pressure of rapidly
changing conditions triggered by global warming and urban growth. For this reason, methods are needed to quantify the successful
application of industrial ecology measures. The “Integrated Sustainability Triangle” is introduced as a promising new possibility
of quantification and monitoring. It enables justification of the contributions industrial ecology can make to sustainable
development. The aggregation of individual economic contributions is assumed to create an overall impetus to the entire industrial
sector including the sector of environmental engineering. Thus, the potential of industrial ecology is discussed from the
macro-economic and the engineering perspective using the concept of sustainable development as a guiding principle. But the
authors come to the conclusion that finding solutions to the pressing problems of our time requires more than collaboration
of economy and engineering. It requires joint efforts of the whole spectrum of scientific disciplines in close collaboration
with industrial and political stakeholders. 相似文献
623.
Tara K. Watson Dorothy Q. Kellogg Kelly Addy Arthur J. Gold Mark H. Stolt Sean W. Donohue Peter M. Groffman 《Journal of the American Water Resources Association》2010,46(2):237-245
Watson, Tara K., Dorothy Q. Kellogg, Kelly Addy, Arthur J. Gold, Mark H. Stolt, Sean W. Donohue, and Peter M. Groffman, 2010. Groundwater Denitrification Capacity of Riparian Zones in Suburban and Agricultural Watersheds. Journal of the American Water Resources Association (JAWRA) 46(2):237-245. DOI: 10.1111/j.1752-1688.2010.00418.x Abstract: We evaluated the relationship of dominant watershed land use to the structure and nitrogen (N) sink function of riparian zones. We focused on groundwater denitrification capacity, water table dynamics, and the presence and pattern of organically enriched deposits. We used the push-pull method (measurement of 15N-enriched denitrification gases derived from an introduced groundwater plume of 15N-enriched nitrate) to evaluate groundwater denitrification capacity on nine forested wetland riparian sites developed in alluvial or outwash parent materials in southern New England. Three replicate sites were located in each of the three watershed types, those with substantial (1) irrigated agriculture, (2) suburban development, and (3) forest. Soil morphology and water table dynamics were assessed at each site. We found significantly lower mean annual water tables at sites within watersheds with substantial irrigated agriculture or suburban development than forested watersheds. Water table dynamics were more variable at sites within suburban watersheds, especially during the summer. Groundwater denitrification capacity was significantly greater at sites within forested watersheds than in watersheds with substantial irrigated agriculture. Because of the high degree of variability observed in riparian sites within suburban watersheds, groundwater denitrification capacity was not significantly different from either forested or agricultural watersheds. The highly variable patterns of organically enriched deposits and water tables at sites within suburban watersheds suggests that depositional events are irregular, limiting the predictability of groundwater N dynamics in these riparian zones. The variability of riparian N removal in watersheds with extensive suburbia or irrigated agriculture argues for N management strategies emphasizing effective N source controls in these settings. 相似文献
624.
森林公园旅游开发是区域开发的一种常见类型,其环境影响评价蕴含着丰富、复杂和值得深入研究的内容。本文着重探讨了评价指导思想、技术路线选择、评价指标体系、评价技术方法等几个关键问题,并以山东药乡国家森林公园旅游开发环境影响评价为例,进一步探讨了有关问题的具体解决办法。 相似文献
625.
Biodiversity and Saving the Earth 总被引:1,自引:0,他引:1
D. J. Rapport 《Environmental monitoring and assessment》1998,49(2-3):169-175
The challenges for reversing course in our stewardship of the earth's ecosystems has never been greater. Biodiversity is in decline on an unprecedented scale and it is tempting to use this as an indicator of the health of the earth's ecosystems. In fact it is one of a number of indicators that collectively provides information on trends in the condition of ecosystems. But the larger problem is the lack of integration between the social and natural sciences. Mainstream scientists continue to reject the notion that solving environmental problems requires an integration of values and processes. A conceptual model shows how these facets may be brought together. A holistic vision requires the integration of natural, social and health sciences. From this perspective the linkage between biodiversity, ecosystem resilience and management options is more clearly articulated. 相似文献
626.
环境库兹涅茨曲线的虚幻性及其对可持续发展的现实影响 总被引:11,自引:1,他引:10
钟茂初 《中国人口.资源与环境》2005,15(5):1-6
生态环境质量真的能够随着经济发展而改善吗?“先污染、后治理”真的是普遍的发展规律吗?既有的理论一般认为.随着经济的发展.生态环境的质量在经过一个时期的恶化之后,将在一定的发展阶段出现好转.其变化过程呈“倒U曲线”状态.这就是环境Kuznets曲线。作者认为这是一个貌似真实的虚幻.生态环境随着经济发展而好转只可能是局部的、而不可能是整体性的.经济发展与生态维护的双赢目标也同样是难以企及的,经济发展与生态维护只能是基于各种利益关系的权衡。文章还对中国长期推行的几种宏观经济政策的生态环境影响进行了分析,并提出了经济利益与生态利益相权衡的现实主张。 相似文献
627.
POST‐HARVEST RIPARIAN BUFFER RESPONSE: IMPLICATIONS FOR WOOD RECRUITMENT MODELING AND BUFFER DESIGN1
Michael K. Liquori 《Journal of the American Water Resources Association》2006,42(1):177-189
Despite the importance of riparian buffers in providing aquatic functions to forested streams, few studies have sought to capture key differences in ecological and geomorphic processes between buffered sites and forested conditions. This study examines post‐harvest buffer conditions from 20 randomly selected harvest sites within a managed tree farm in the Cascade Mountains of western Washington. Post‐harvest wind derived treefall rates in buffers up to three years post‐harvest averaged 268 trees/km/year, 26 times greater than competition‐induced mortality rate estimates. Treefall rates and stem breakage were strongly tied to tree species and relatively unaffected by stream direction. Observed treefall direction is strongly biased toward the channel, irrespective of channel or buffer orientation. Fall direction bias can deliver significantly more wood recruitment relative to randomly directed treefall, suggesting that models that utilize the random fall assumption will significantly underpredict recruitment. A simple estimate of post‐harvest wood recruitment from buffers can be obtained from species specific treefall and breakage rates, combined with bias corrected recruitment probability as a function of source distance from the channel. Post‐harvest wind effects may reduce the standing density of trees enough to significantly reduce or eliminate competition mortality and thus indirectly alter bank erosion rates, resulting in substantially different wood recruitment dynamics from buffers as compared to unmanaged forests. 相似文献
628.
Photosynthetically fixed energy from the sun, in the form of net primary production, ultimately supports the majority of life
on earth. Given the importance of this energy source, we calculate the human appropriation of net primary production (HANPP)
for the province of Nova Scotia, Canada. We find that over 25% of potentially available production is appropriated by humans
through harvest (forestry and agriculture) and land cover change. The level of appropriation in Nova Scotia is close to the
global average, when methodological differences between studies are taken into account, but substantially less than in Austria
and India where detailed surveys have also been conducted. Furthermore, HANPP is not distributed evenly throughout the province,
but is instead concentrated in the north-central counties, where appropriation reaches 50%. We discuss the implications of
these results, and the novel method used to obtain them, in the context of biophysical assessment and the species-energy hypothesis. 相似文献
629.
文章论述了城市生态化及其发展对策 ,提出可持续城市发展的概念及其生态原则 ,以期推动我国城市生态化和可持续城市建设工作的开展 相似文献
630.
--A region
surrounding Qinghai Lake was chosen as thestudy area and nine ecological landscape types
that were recognizedbased on Landsat TM image classification of land cover/use typesalong
with the ancillary data, and their ecological features andthe measures dealing with the
eco-environmental problems arepresented in this paper. The study has shown that using
thisapproach the ecological landscape types in a region like the studyarea can be readily
recognized and their ecological features can berather accurately derived. Moreover, the
deterioration in near alllandscape ecological types in the area is quite serious.
Therefore,effective and proper measures have to be taken in order to realizea sustainable
development of the region. 相似文献