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131.
Jürgen Bennewitz 《Environment, Development and Sustainability》2009,11(1):127-136
The IPCC Working Groups I–III 2007 publications does not consider the question of the influence of the entropy increase in
the atmosphere on current climate development. An investigation into this question, both in general terms as well as by two
quantitative approaches, reveals we must consider the entropy produced by man in connection with climate development, especially
with regard to the temperature increase of the atmosphere. The IPCC report also fails to mention the production of CO2 by humans and livestock, but calculations show we must also consider such greenhouse gas CO2 production. For solving the mitigating processes, we therefore have to take into account both the human induced entropy production
and the direct human and livestock CO2 output. In consideration of these findings, it seems necessary to introduce an “entropy identity” to people who wish to be
able to continue to live on the planet. The introduction of an entropy tax might also help in solving the most urgent fundamental
problem humanity has ever had to face.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
132.
Ecological impacts of water-quality problems have developed in the western United States resulting from the disposal of seleniferous
agricultural wastewater in wetland areas. Overt effects of selenium toxicosis occurred at five areas where deformities of
wild aquatic birds were similar to those first observed at Kesterson National Wildlife Refuge in the west-central San Joaquin
Valley of California. These areas are: Tulare Lake Bed Area, California, Middle Green River Basin, Utah, Kendrick Reclamation
Project Area, Wyoming, Sun River Basin, Montana, and Stillwater Wildlife Management Area, Nevada. Potential for ecological
damage is indicated at six more sites in Oregon, Colorado, the Colorado/Kansas border, and South Dakota out of 16 areas in
11 states where biological tissue data were collected. This conclusion is based on the fact that selenium bioaccumulated in
bird livers to median levels that had exceeded or were in the range associated with adverse reproductive effects. Selenium
concentrations in samples of fish and bird eggs support these conclusions at a majority of these areas. Reason for concern
is also given for the lower Colorado River Valley, although this is not exclusively a conclusion from these reconnaissance
data. Biogeochemical conditions and the extent of selenium contamination of water, bottom sediment, and biota from which this
assessment was made are given here. In a companion paper, the biogeochemical pathway postulated for selenium contamination
to take place from natural geologic sources to aquatic wildlife is defined. 相似文献
133.
Kent RC 《Disasters》2004,28(2):216-233
Changes in the nature of humanitarian crises and in the ways that the international community responds to such crises demand a radically overhauled role for the United Nations system. At a time when the UN and its member states are pursuing reform of some of that institution's most fundamental peace and security functions, this paper suggests that reform, too, is required to meet humanitarian crises of the future. This paper proposes a new type of operational role for the UN, while at the same time arguing that the UN has to place itself in the vanguard of humanitarian assistance as "the standard-bearer". The article draws many of its conclusions and recommendations from a recently completed study, requested by the Inter-Agency Standing Committee, concerning the effect for the UN system of changes in humanitarian financing. 相似文献
134.
Central and Eastern Europe (CEE) is a rapidly changing and developing region which is making the transition to a market based economy. Along with economic reforms, the countries of the region are engaged in substantial environmental reforms, including climate change mitigation activities. Mitigation of, and adaptation to, the consequences of climate change are costly processes. It is therefore of great importance that the national and international mechanisms addressing these problems use methods both environmentally sound and economically efficient. Through two case studies that address the Clean Development Mechanism (CDM) in the Former Yugoslav Republic of Macedonia, and the Green Investment Scheme (GIS) in Romania, this paper explores challenges, related tasks and main problems in the establishment of mechanisms of the Kyoto Protocol in Central and Eastern Europe. 相似文献
135.
Decision Support for Road System Analysis and Modification on the Tahoe National Forest 总被引:1,自引:0,他引:1
The United States Forest Service is required to analyze road systems on each of the national forests for potential environmental impacts. We have developed a novel and inexpensive way to do this using the Ecosystem Management Decision Support program (EMDS). We used EMDS to integrate a user-developed fuzzy logic knowledge base with a grid-based geographic information system to evaluate the degree of truth for assertions about a roads environmental impact. Using spatial data for natural and human processes in the Tahoc National Forest (TNF, California, USA), we evaluated the assertion the road has a high potential for impacting the environment. We found a high level of agreement between the products of this evaluation and ground observations of a TNF transportation engineer, as well as occurrences of road failures. We used the modeled potential environmental impact to negatively weight roads for a least-cost path network analysis to 1573 points of interest in the forest. The network analysis showed that out of 8233 km of road analyzed in the forest, 3483 km (42%) must be kept in a modified road network to ensure access to these points. We found that the modified network had improved patch characteristics, such as significantly fewer cherry stem roads intruding into patches, an improved area-weighted mean shape index, and larger mean patch sizes, as compared to the original network. This analysis system could be used by any public agency to analyze infrastructure for environmental or other risk and included in other mandated analyses such as risks to watersheds. 相似文献
136.
John Dover Tim Sparks Sue Clarke Kay Gobbett Sarah Glossop 《Agriculture, ecosystems & environment》2000,80(3):179
Green lanes are unmetalled tracks between fields of variable width, which may be sunk below or raised above field level, and bounded on both sides by ‘grass’ banks, hedgerows or dry-stone walls. In the UK they have no unique planning status and have been overlooked as discrete landscape elements. Green lanes were surveyed for butterflies in 1997 on lowland arable farmland on the Trafford/north Cheshire border (Warburton) and on upland grassland in the Yorkshire Dales (Ribble Valley). At the lowland site the green lanes were bounded by vegetation and were compared with grass banks and single hedgerow field boundaries; at the upland farm, the green lanes were bounded by dry-stone walls and were compared with grass banks and single dry-stone walls. Data from earlier work on a largely arable farm (Manydown) in Hampshire in 1987 and 1988 were re-analysed to make comparisons between a green lane, the rides and glades of two coppiced woodlands, and the grass banks and single hedgerows surrounding arable fields. Green lanes, whether bounded by vegetation or stone were superior to other common farmland biotopes with the exception of woodland, in terms of both butterfly abundance and species richness.Multiple regression of the Warburton data indicated the importance of green lanes, adjacent habitat type, and nectar sources for species richness and butterfly abundance. The interior of green lanes had lower windspeeds, and more bramble nectar sources than hedgerows or grass banks. By their nature they occupy a larger area of uncropped land, and are subject to a reduced disturbance regime and reduced inputs of agrochemicals and fertilisers. Their value as biodiversity reservoirs in intensively managed land is likely to be high. 相似文献
137.
美国《濒危物种法》对联邦机构的要求--美国《濒危物种法》第七章浅析 总被引:1,自引:0,他引:1
目前,在世界范围内,美国《濒危物种法》可以说是物种保护方面最强有力的国内立法,它规定了两项国家政策,其一就是要求所有的联邦部门和机关都必须努力保护濒危物种并运用其权力促进《濒危物种法》立法宗旨的实现。本文简要介绍美国《濒危物种法》的历史发展和其第七章的主要内容,分析美国《濒危物种法》对联邦机构在物种保护中的要求。 相似文献
138.
Cairns Michael A. Winjum Jack K. Phillips Donald L. Kolchugina Tatyana P. Vinson Ted S. 《Mitigation and Adaptation Strategies for Global Change》1997,1(4):363-383
This research assessed land-use impacts on C flux at a national level in four countries: former Soviet Union, United States,
Mexico and Brazil, including biotic processes in terrestrial ecosystems (closed forests, woodlands, and croplands), harvest
of trees for wood and paper products, and direct C emission from fires. The terrestrial ecosystems of the four countries contain
approximately 40% of the world's terrestrial biosphere C pool, with the FSU alone having 27% of the global total. Average
phytomass C densities decreased from south to north while average soil C densities in all three vegetation types generally
increased from south to north. The C flux from land cover conversion was divided into a biotic component and a land-use component.
We estimate that the total net biotic flux (Tg/yr) was positive (= uptake) in the FSU (631) and the U.S. (332), but negative
in Mexico (−37) and Brazil (−16). In contrast, total flux from land use was negative (= emissions) in all four countries (TgC/yr):
FSU −343; U.S. −243; Mexico −35; and Brazil −235. The total net effect of the biotic and land-use factors was a C sink in
the FSU and the U.S. and a C source in both Brazil and Mexico.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
139.
The U.S. and China are the world's largest and second largest CO2 emitters, respectively, and to what extent the U.S. and China get involved in combating global climate change is extremely important both for lowering compliance costs of climate mitigation and adaptation and for moving international climate negotiations forward. While it is unavoidable that China will take on commitments at some specific point of time in the future, this paper has argued that the proposal for joint accession by the U.S. and China is not a way forward. For various reasons, such a proposal is in the U.S. interest, but is not in the interest of China. Given the U.S. political reality and institutional settings on the one hand and China's over-riding concern about economic growth and poverty reduction on the other, the two countries are unlikely to take on emissions caps under an international regime, at least for the time being. Therefore, we need to explore the area where cooperation between the two countries to address climate change seems best. The research, development and deployment of clean technology is the area that is in the best interests of the two countries. The U.S. has adopted a technology-oriented approach to climate issues, and has launched the four multilateral initiatives on technology cooperation and the Asia Pacific Partnership for Clean Development and Climate (APP). China has participated in all these U.S.-led initiatives, and is a partner to the APP. Strengthened technology cooperation between the two countries through these initiatives and the APP has led some tangible benefits. However, it should be pointed out that while technology is a critical ingredient in a climate policy package, efforts such as the APP can only be part of the solution. They alone cannot ensure that best available technologies are always deployed in the marketplace, and that new technologies will roll out at the pace and on the scale that we need. In order to have such technology-oriented approach to play a full role, we do need a coordinated policy framework agreed via the Kyoto Protocol or a follow-up regime or the parent United Nations Framework Convention. 相似文献
140.
Kiljunen K 《Disasters》1983,7(2):129-141
This paper, abstracted from the final report of the Kampuchea Inquiry Commission, analyses the population losses in Cambodia prior to 1979 and goes on to describe some of the unwanted side effects of the international relief programmes in both Thailand and in Kampuchea. The paper concludes that various opposition movements to the present Vietnamese backed regime in Kampuchea have been strengthened by international aid. 相似文献