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1.
Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin. It is difficult to identify the sources and to quantify the load, especially in modeling nonpoint source. In this study a revised model was established by integrating point and nonpoint sources into one-dimensional Streeter-Phelps (S-P) model on the basis of real-time hydrologic data and surface water quality monitoring data in the Jilin Reach of the Songhua River Basin. Chemical oxygen demand (COD) and ammonia nitrogen (NH_3-N) loads were estimated. Results showed that COD loads of point source and nonpoint source were 134 958 t/yr and 86 209 t/yr, accounting for 61.02% and 38.98% of total loads, respectively. NH_3-N loads of point source and nonpoint source were 16 739 t/yr and 14 272 t/yr, accounting for 53.98% and 46.02%, respectively. Point source pollution was stronger than nonpoint source pollution in the study area at present. The water quality of upstream was better than that of downstream of the rivers and cities. It is indispensable to treat industrial wastewater and municipal sewage out of point sources, to adopt the best management practices to control diffuse pollutants from agricultural land and urban surface runoff in improving water quality of the Songhua River Basin. The revised S-P model can be successfully used to identify pollution source and quantify point source and nonpoint source loads by calibrating and validating.  相似文献   

2.
WATER POLLUTION IN CHINA:CURRENT STATUS, FUTURE TRENDS AND COUNTERMEASURES   总被引:2,自引:0,他引:2  
Based on the statistical data related to water pollution in recent years, this paper firstly describes in detail the current status of water pollution and water quality in rivers, lakes, reservoirs, groundwater and coastal waters in China, then makes a comprehensive analysis on future trends of water pollution in China. The authors hold that the economic power, technology level and management level have determinative influences on the current status and future trends of water pollution. At last, this paper discusses briefly the policies and measures for preventing and controlling water pollution in the light of the national conditions.  相似文献   

3.
China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages’ dilemmas include the nonuniformity of actors’ objectives, finiteness of villagers’ abilities, and the imperfect incentive and restraint mechanism for local government’s activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China’s rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels.  相似文献   

4.
在开放条件的今天,历时50余年的农业合作银行已不适应当前形势的发展,农村合作金融的生存和发展是一个迫切需要解决的问题。通过对我国农村合作金融的变迁进行回顾与分析,总结历史经验和教训,提出应对目前农村合作金融管理体制和相关金融法律法规政策制度进行改革。  相似文献   

5.
农事活动对水文系统的干扰已成为水资源恶化的重要因素。通过大量事例概述了农事活动对水资源的主要影响,分析了农业区受污染地下水的地球化学类型,从保护水资源的角度,提出了防止农业非点源污染的控制和管理对策。  相似文献   

6.
随着南方丘陵区开发利用强度的增大,氮、磷非点源污染和水体富营养化问题日益突出。由于流域尺度非点源污染过程的复杂性,难以建立大范围、重复可控的观测和实验环境,模型模拟成为非点源污染治理辅助决策的必要手段。已有学者对南方丘陵区非点源污染过程模拟开展了相关研究,但缺乏对已有成果及其存在问题的系统总结以及对下一步研究方向的分析探讨。本文首先分析了南方丘陵区非点源污染过程的机理,认为该地区的非点源污染过程模拟应满足多过程耦合、空间全分布式及考虑区域特点等要求;然后,对南方丘陵区非点源污染过程模拟研究现状以及存在问题进行了分析,总结了现有研究在描述非点源污染物迁移路径和反映区域特点等方面的不足;最后,从适合南方丘陵区特点的流域空间离散化方法、全分布式非点源污染物迁移路径的构建、特殊地物和人为活动在全分布式非点源污染模型中的综合表达等方面探讨了下一步研究方向,旨在为南方丘陵区非点源污染过程模拟研究提供参考和借鉴。  相似文献   

7.
Rapid urbanization and growing size of cities will have an increasing impact on the global environment in the 21st century. As an engine of urban development to drive economic growth and technological innovations, industry has moved its focus from controlling environmental hazards to stimulating sustainable industrial development throughout the entire product lifecycle. These process- and technology-driven innovations for industrial production are prerequisites for enhancement of urban environment and sustainable development of cities. In this review, problems of environment and resources scarcity associated with rapid urbanization are demonstrated. And, on the basis of expatiations on the concepts and policies of the cleaner production (CP) and other similar initiatives with the goal of preventing pollution at the source and of managing the raw material more efficiently, two different ways to link the practice of cleaner production in industrial sector with performance of urban environment are discussed in detail. Then, the introduction, practice and legislation of CP strategies in China are outlined, and possibility for China to develop CPC (Cleaner Practices for Cities) approaches in the demonstration cities is discussed. Finally, some suggestions on implementation of CPC strategies are put forward.  相似文献   

8.
区域尺度农田氮磷非点源污染与模型应用分析   总被引:3,自引:0,他引:3  
分析了农田非点源污染对生态环境的危害性,并阐述农田氮、磷非点源污染的机理及其在不同自然条件下的影响因素和监测方法。同时,对农田非点源污染的定量化、应用效应等进行了对比分析。此外,结合农田非点源污染与相关模型作了应用实例分析。  相似文献   

9.
Policy and Practice Progress of Watershed Eco-compensation in China   总被引:2,自引:0,他引:2  
The ecological protection of the watersheds in China is being confronted with a lot of problems such as soil and water erosion, water pollution at present. Therefore watershed eco-compensation is becoming a question of common interest. Based on the analyses of the major problems and their origins in the watershed protection in China, the paper discusses the concerned policies including relative rules and laws, financial policies and water right transaction policies. Simultaneously the paper reviews the practices carried out in China, including the ecological construction project in the western China, the trans-provincial eco-compensation practice and the small watershed eco-compensation practice. According to the present situation of eco-compensation practices and the future policy requirement, this paper finally puts forward four key problems to be solved in the watershed eco-compensation of China in the future.  相似文献   

10.
最佳管理措施(BMP)是治理流域土壤侵蚀、非点源污染等环境问题的有效途径,基于流域过程模拟的情景优化方法可得到综合效益近似最优的BMP空间配置方案集。目前用于配置BMP的空间单元(如子流域、水文响应单元、地块、坡位)均不能有效地综合体现BMP与地形部位间的空间关系以及同一地形部位内不同土地利用斑块上的BMP差异。本文提出将坡位单元与地块单元叠加生成的坡位-地块单元作为BMP空间配置单元,结合分布式流域建模框架SEIMS和多目标优化算法NSGA-II建立一套流域BMP空间优化配置方法。以江苏省溧阳市中田舍流域的非点源污染治理为例,选取减量施肥、退耕还林、封山育林和生态林草4种典型BMP,以最大化总氮削减率、最小化经济成本为优化目标,分别采用坡位单元、地块单元、坡位-地块单元进行情景优化。结果表明:相比坡位单元和地块单元,采用坡位-地块单元可获得最多具有近似最优综合效益的BMP情景,定量评价解集分布性和收敛性的Hypervolume指数分别提升了7%和4%,且BMP在空间上分布更加精细、配置更加灵活。本文方法可有效、合理地优化流域最佳管理措施的空间配置,为流域治理提供决策支持。  相似文献   

11.
The Road to Rio+20 is the journey of countries in the world pursuing the sustainable development.As the first country to release the national Agenda 21,China’s experience and lessons are of great significance for both China itself and other countries.The paper reviews the progress made and problems remained in pursuing the sustainable development in China with regard to policy formulation,institutional arrangements,planning and management.In the past five years,the mandatory targets-driven approach,which focused on energy efficiency and key pollutants reduction,played a very important role and made China comprehensive outcomes for sustainability.In order to achieve the targets,China adopted an integrated policy package including legal,administrative,economic and technology instruments.During the 12th Five-Year Plan period(2011-2015),China will continue and strengthen the approach above and mainstream the transformation of economic development pattern through realizing the idea of green and low-carbon development.By summarizing policy trends in the world,the paper points out two directions,i.e.,integration approach and taking prioritized and concrete actions for a sustainable future beyond 2012.The paper also presents policy approaches and recommendations for sustainable development in the next 10 years in China.  相似文献   

12.
Based on the provincial units evaluation,this paper makes an assessment for sustainable developing capability of the integrated agricultural regionalization in China.At first ,an index system of agricultural sustainable development in China is built up,which includes 5 supporting subsystems of agricultural resources,agricultural develop-ment ,environment and ecosystem,rural society,sciences-esucation and management.We selected 95 factors on provin-cial level as basic indexes.Second,a relative assets/debt assessing method is used to gain relative net assets values (relative superiority) of every provincial unit,which are as supporting data for assessment.We also overlaid the Administra-tive Divisions Map of China and the Map of Integrated Agricultural Regionalization of China by Geography Information Sys-tem(GIS) to gain the area units of assessment.Third,according to the relative coherence principle of regionalization,we transform administration units to natural units through homogenizing all provincial relative net assets values in every agricultural assessing unit.After making order and grade,we complete the sustainable developing capability assessment to integrated agricultural regionalization in China.The assessing outcome shows that the total sustainable agricultural devdelop-ing capability of China is not high.Only about 1/3 in number or in area has reached the level of agricultural sustainable development.The relative net assets values exists a reducing trend from East China to West China.It needs a long period and great efforts to realize sustainable agricultural development over all China.Finally,there is a discussion to the study method.  相似文献   

13.
In this study, an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP) and its spatial convergence at national and provincial levels in China from 1999 to 2017. On this basis, spatial factors affecting ANSP were explored by constructing a spatial econometric model. The results indicate that: 1) The intensity of China's ANSP emission showed an overall upward trend and an obvious spatial difference, with the values being high in the eastern and central regions and relatively low in the western region. 2) Significant spatial agglomeration was shown in China's ANSP intensity, and the agglomeration effect was increasing gradually. 3) In the convergence analysis, a spatial lag model was found applicable for interpretation of the ANSP intensity, with the convergence rate being accelerated after considering the spatial factors but slower than that of regional economic growth.4) The spatial factors affecting the ANSP intensity are shown to be reduced by improving agricultural infrastructure investment, laborforce quality, and crop production ratio, while the expansion of agricultural economy scale and precipitation and runoff have positive impact on ANSP in the study region. However, agricultural research and development(RD) investment showed no direct significant effect on the ANSP intensity. Meanwhile, improving the quality of the labor force would significantly reduce the ANSP intensity in the surrounding areas, while the precipitation and runoff would significantly increase the pollution of neighboring regions. This research has laid a theoretical basis for formulation and optimization of ANSP prevention strategies in China and related regions.  相似文献   

14.
The implementation of pasture contracting policies in the Tibetan Plateau has been of widespread concern in the scientific community and related government departments. Studying the effects of the implementation of pasture contracting policies will help us understand herders' attitudes toward those policies and to amend existing policies effectively. This paper analyzes 135 herder families' grazing management behavior using participatory rural appraisal (PRA), quantitative analysis and a Logistic regression model in three townships of Nagqu County in remote areas of the Tibetan Plateau, China. The results show that the herders have become settled and are no longer nomadic, so the settlement project has basically been completed and the policy of contracting for grazing rights is being gradually implemented in Nagqu County. Since the grazing rights and pastures were under contract, group-based management has been widely accepted in this area, which helps the herders deal with constraints, such as limited pasture area, a small grazing radius, controlled family animal husbandry and an uneven distribution of water. The herders that have more family members available for labor, higher proportion of family members with good health, and higher income from animal husbandry tend to choose household-based management. Herders tend to choose group-based management when higher quality winter pastures are available.  相似文献   

15.
Agricultural village is an important rural type in China. The evolution process and mechanism of its cultural landscape are different from those of the industrialized village. The paper focuses this theme by a case study of Qianzhai Village of Qufu City, Shangdong Province. In the case of Qianzhai Village, the evolution of its settlement has experienced three stages: mechanical expansion, sprawling expansion and hollowing, and recentralization. The land- scape evolution of residents' houses has undergone three phases: traditional quadrangle house, one-storied house and multistoried house. The evolution of its land use has experienced three stages: circled stratification, fragment and intensive use, and concentration and extensive use. We can see that the main driving factors of cultural landscape evolution of agricultural village are the changes of rural population, society, economy and culture, which are influenced by the change of urban-rural relation, the national modernization process and economic development, the reform of family planning and land system, and the changes in governmental policies. In the future, the modernization, ecological trend, and individualization for residents' houses of agricultural villages in China will develop step by step. The recentralization of settlement and the scaled, sustainable, intensive land use are likely to be the trends of agricultural villages in China.  相似文献   

16.
Market-based emission trading schemes (ETSs) are widely used in the developed world to reduce greenhouse gas (GHG) emissions which are perceived as the source of global climate change. China, as the largest GHG emitter in the world, is committed to introducing an ETS to reduce emissions. Here we reviewed existing ETSs and sustainable energy policies worldwide as well as China’s pilot programs. These studies were conducted in order to propose recommendations for national initiatives and strategies to be implemented in China in relation to climate change adaptation and mitigation. It has been shown that setting emission caps in the context of a national emission intensity target is difficult. However, implementing reliable systems for measurement, reporting, and verification of emissions are essential. A two-level management system (by central and provincial governments) for carbon trading is beneficial to ensure uniform standards and compliance while maintaining flexibility. Persistent political support from, and effective coordination of, policies by the government are crucial. In addition, strengthening of institutional innovation, and the establishment of a national GHG emissions information system, are of equal importance. This vital information could provide a great opportunity for China to re-define its economic growth and take global leadership in combatting climate change.  相似文献   

17.
随着我国农业现代化发展,传统农业逐步向现代农业转变,尤其是近年来农村土地承包经营权流转进程加快,农业生产经营规模不断扩大,农业设施快速增加,势必要占用大量的农用地。因此,为适应现代农业发展需求,必须加强和完善设施农用地管理,防止以发展设施农业为名,滥占乱用土地,促进耕地保护和设施农业的健康有序发展。  相似文献   

18.
Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of FEZ in the less developed countries and little attention has been paid to the evolution of FEZ. This paper will improve the above-mentioned studies and put forward the structural and spatial evolutionary model of FEZ by analyzing the development of objectives, preferential policy, governance structure, industrial sectors and location of FEZs based on the international economic and political development. FEZs develop towards: 1) more comprehensive and macro objectives, 2) more industry-oriented and multi-preferential policies, 3) more cross-national and combination zones with administrative areas, 4) more technology-intensive and multi-industries, 5) more flexible location and larger spatial dimensions, 6) more rapid evolution and typologies, and 7) more economic integration to the host economy. Biography: MENG Guang-wen (1960–), male, a native of Tianjin of China, Ph.D., specialized in regional planning and policy, environmental planning, tourist planning and management. E-mail: gwmeng98@hotmail.com  相似文献   

19.
Rural off-farm employment, rapid loss of agricultural land, and advanced technology popularization had led agricultural production in Chinese typical rural areas come at a critical transformation and upgrade stage. Based on sample survey data gathered from 401 households in Yucheng City, Shandong Province, this paper focuses on the characteristics and mechanism of agricultural transformation in typical rural areas of the eastern China. It was found that 74.3% of households surveyed kept at least one member engaging in off-farm employment, and 57.1% looked forward to expanding the operational scale of arable land, while just 13.7% had actually transferred their agricultural land. Since growing off-farm employment does not result in the collapse of traditional subsistence agriculture, therefore, agricultural production in Yucheng City is at an incomplete transformation phase from traditional small-holder farming to modern scale economy. It is caused by both macro environments and family characteristics, while urban-rural dual structure, imperfect rural development policy and agricultural technology popularization make peasant economy strengthen upon maintenance, and small-holder farming becomes peasant’s natural response owing to pluriactivity, local off-farm employment, reverse elimination, etc. In order to achieve smooth agricultural transformation of typical rural areas in the eastern China, it needs to promote professional differentiation among peasants, under clear policies adopted by central government. Providing comprehensive services for agricultural production and improving production skills and knowledge of farmers who are still living in the countryside will effectively stimulate the process of agricultural transformation.  相似文献   

20.
王公芹 《山东国土资源》2011,27(8):42-44,48
耕地总量动态平衡是我国目前耕地保护的重要组成部分,它与我国社会经济发展战略密切相关。该文分析了当前耕地总量动态平衡政策内涵及在现实中存在的若干问题,通过对平邑县耕地总量动态平衡实施情况的调研分析,对目前耕地总量和动态平衡的完善和实施政策提出了若干建议。  相似文献   

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