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51.
Severe soil erosion in the upper reaches of the Yangtze River and the middle reaches of the Yellow River is a serious environmental problem in western China. In order to control this soil erosion, the national government implemented the Grain for Green Program (GGP) in Sichuan Province (in the upper reaches of the Yangtze River) and Shaanxi Province (in the middle reaches of the Yellow River) in 1999. To evaluate the effects of the GGP on soil erosion, the present study investigated the relationships between annual precipitation and three parameters, annual runoff, sediment concentration, and sediment discharge, for these rivers. As the area covered by the GGP increased, sediment concentration and sediment discharge both decreased, and the correlation with the GGP area was much stronger than the correlation with annual precipitation. Therefore, China's GGP appears to be controlling soil erosion in the upper reaches of the Yangtze River and the middle reaches of the Yellow River.  相似文献   
52.
A two-dimensional numerical model for eutrophication in Baiyangdian Lake   总被引:1,自引:1,他引:0  
Hydrodynamic, physical, and biochemical processes in the Baiyangdian Lake water environment were analyzed comprehensively. An eutrophication ecodynamics model including the effects of reed resistance on flow was coupled with the hydrodynamics governing equations. An improvement on the Water Quality Analysis Simulation Program (WASP, a modeling system introduced by the US Environmental Protection Agency) is established, which uses the zooplankton kinetic equation. The model simulates water quality constituents associated with eutrophication in the lake, including phytoplankton, zooplankton, nitrogen, phosphorus, dissolved oxygen, and others. Various kinetic coefficients were calibrated using measured data or information from relevant literature, to study eutrophication in the lake. The values calculated by the calibrated model agree well with field data, including ammonia nitrogen, total nitrogen, total phosphorus and dissolved oxygen. Changes related to nutrition and dissolved oxygen during the processes were simulated. The present model describes the temporal variation of water quality in Baiyangdian Lake with reasonable accuracy. Deviations between model-simulated and observed values are discussed. As an ideal tool for environmental management of the lake, this model can be used to predict its water quality, and be used in research to examine the eutrophication process.  相似文献   
53.
周斌 《中国环境管理》2017,9(2):101-104
2015年2月,科技部发布国家重点研发计划“水资源高效开发利用”重点专项2016年度指南,历经申报和立项评审,最终有31个项目获得立项支持。本文简述了中国21世纪议程管理中心作为承担本专项过程管理任务的专业机构,在2016年项目申报过程中的工作流程和相关数据分析,对今后开展有关工作提出了建议,为相关领域科研人员申报本专项项目提供一定参考。  相似文献   
54.
Viña A  Chen X  McConnell WJ  Liu W  Xu W  Ouyang Z  Zhang H  Liu J 《Ambio》2011,40(3):274-284
Conservation policies are increasing in response to human-induced ecosystem degradation, but little is known about their interplay with natural disasters. Through an analysis of satellite imagery and field data we evaluated the impacts of a devastating earthquake on forest recovery and avoided forest loss estimated to have been obtained by two of the largest conservation programs in the world. Results show that more than 10% of the forests in Wenchuan County, Sichuan province, China were immediately affected by the 2008 earthquake, offsetting some gains in forest cover observed since the enactment of the conservation programs. But without the enactment of these conservation programs, the combined effects of human disturbance and earthquake-induced landslides could have severely reduced the region’s forest cover. The continuation—and enhancement—of incentives for participation in conservation programs will be important for reducing the environmental impacts of the combined effects of human disturbance and natural hazards not only in the study area but also in many disaster-prone regions around the world.  相似文献   
55.
This paper presents the results of the Environmental Monitoring Program for the Radioactive waste repository of Abadia de Goiás, which was originated from the accident of Goiania, conducted by the Regional Center of Nuclear Sciences (CRCN-CO) of the National Commission on Nuclear Energy (CNEN), from 1998 to 2008.The results are related to the determination of 137Cs activity per unit of mass or volume of samples from surface water, ground water, depth sediments of the river, soil and vegetation, and also the air-kerma rate estimation for gamma exposure in the monitored site.In the phase of operational Environmental Monitoring Program, the values of the geometric mean and standard deviation obtained for 137Cs activity per unit of mass or volume in the analyzed samples were (0.08 ± 1.16) Bq.L−1 for surface and underground water, (0.22 ± 2.79) Bq.kg−1 for soil, and (0.19 ± 2.72) Bq.kg−1 for sediment, and (0.19 ± 2.30) Bq.kg−1 for vegetation. These results were similar to the values of the pre-operational Environmental Monitoring Program.With these data, estimations for effective dose were evaluated for public individuals in the neighborhood of the waste repository, considering the main possible way of exposure of this population group.The annual effective dose obtained from the analysis of these results were lower than 0.3 mSv.y−1, which is the limit established by CNEN for environmental impact in the public individuals indicating that the facility is operating safely, without any radiological impact to the surrounding environment.  相似文献   
56.
The Conversion of Cropland to Forest and Grassland Program (CCFG), which was initiated by the Chinese government in 1999, is a cropland retirement program with integrated objectives for ecological preservation and local development. The purpose of this article was to study the influencing factors of attitude and economic strategies in rural households toward the CCFG. Rural households’ knowledge, attitude and economic strategies toward the CCFG were investigated through a questionnaire survey in Qira, China. Influencing factors of attitude and strategies of households were analyzed using a logit model technique. The analysis indicated that household’s income level, environmental knowledge of the program, and program implementation were significant influencing factors in a household’s attitude toward the CCFG, while major influencing factors of household strategies were their regional background and availability of income generation sources. Meaningful association was not found between attitude and strategy choices. Rich households had more strategy choices, while poor households were usually confined to low input strategies with uncertain income. To sustain their livelihood, the poor need extra assistances in marketing, loan granting, employment training, information, and technical services.  相似文献   
57.
草原生态补偿:生态绩效、收入影响和政策满意度   总被引:2,自引:0,他引:2  
草原生态保护补助奖励机制的第一轮实施期(2011-2015)即将结束,系统地评估草原生态保护补助奖励机制,对于完善下一期补助奖励机制具有重要的借鉴意义。本文利用2014年内蒙古自治区阿拉善左旗、四子王旗、陈巴尔虎旗三个旗县的470户牧户样本数据,从生态绩效、收入影响、政策满意度三个方面对草原生态补偿政策(即草原生态保护补助奖励机制)进行了评估。生态绩效评估结果表明:草原生态环境得到了一定的改善,草原利用方式更趋合理,平均牲畜超载率下降明显,但超载过牧的现状没有得到根本的转变,样本调研旗县2011-2014年减畜任务达成比例为42%,总体减畜任务达成情况一般。收入影响评估结果表明:平均每户理论收入影响为-8 607元,草原生态补偿标准偏低,需要在原有基础上提高35%;平均每户的实际收入影响为16 686元,牧民没有严格按照政策要求进行完全的减畜;草原生态补偿标准不只是单纯标准偏低的问题,同时也有标准差别化问题,需要在不同地区之间做出调整。政策满意度评估结果表明:草原生态补偿政策的满意度为57%,其中陈巴尔虎旗的政策满意度最高,为87%;四子王旗其次,为62-63%;阿拉善左旗最低,为18-32%。政策满意度与实际收入影响之间存在显著的相关关系,实际收入影响正向越大,政策满意度越高。牧民对草原生态补偿政策的政策满意度越高,并不意味着草原生态补偿的政策设计和执行就越好,政策满意度越高,实际收入影响正向越大,但生态效果可能不佳。  相似文献   
58.
Hughes, Robert M., Alan T. Herlihy, and Philip R. Kaufmann, 2010. An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States. Journal of the American Water Resources Association (JAWRA) 46(4): 792-806. DOI: 10.1111/j.1752-1688.2010.00455.x Abstract: Assessment of stream physical habitat condition is important for evaluating stream quality globally. However, the diversity of metrics and methods for assessing physical habitat condition confounds comparisons among practitioners. We surveyed 51 previously sampled stream sites (0.0-6.3 m wide) located in regions of row-crop agriculture in Oregon, California, North Dakota, South Dakota, Nebraska, Iowa, Minnesota, Pennsylvania, Maryland, and West Virginia to evaluate the comparability of four indexes of physical habitat condition relative to each other. We also compared the indexes to previously calculated indexes of fish and macroinvertebrate condition. The physical habitat indexes included the Stream Visual Assessment Protocol Version 2 of the Natural Resources Conservation Service, the qualitative habitat evaluation index of the Ohio Environmental Protection Agency, the rapid bioassessment protocol of the United States Environmental Protection Agency (USEPA), and a qualitative physical habitat index based on USEPA quantitative physical habitat measurements. All four indexes were highly correlated with each other, but low-to-moderately correlated with biotic index scores for fish and macroinvertebrate assemblages. Moderately high correlations occurred between some macroinvertebrate biotic index scores and quantitative metrics. We conclude that additional research is needed to increase the predictive and diagnostic capabilities of qualitative physical habitat indexes.  相似文献   
59.
Environmental Education and Education for Sustainable Development (EE&ESD) have been widely accepted as an effective educational method to contribute to capacity development and processes of change in developing countries. This paper takes SIDA supported EE&ESD in formal educationadvanced international training program, China as an example. By analyzing and reflecting its orientation, implementation, outcomes and evaluation, experiences and lessons learned are expected to help improve the sorts of international cooperation capacity building programs both from international and also Chinese perspectives.  相似文献   
60.
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   
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