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ESTIMATION OF ECOLOGICAL SERVICE VALUES OF WETLANDS IN SHANGHAI, CHINA 被引量:24
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作者 LIBo ZHONGYang +1 位作者 NAKAGOSHINobukazu CHENJia-kuan 《Chinese Geographical Science》 SCIE CSCD 2005年第2期151-156,共6页
Shanghai is a coastal metropolitan city with various types of natural wetlands, which account for 23.5% of its total area. According to the definition of wetland in Ramsar Convention on Wetlands, the wetlands of Shang... Shanghai is a coastal metropolitan city with various types of natural wetlands, which account for 23.5% of its total area. According to the definition of wetland in Ramsar Convention on Wetlands, the wetlands of Shanghai were classified into 4 types: coastal, riverine, lacustrine, and reservoir and pond wetlands. In order to examine the roles of wetlands in the life-support system of Shanghai, we calculated the area of each type of the wetlands using GIS technique, and then measured the ecological service values of different ecosystems in Shanghai based on the classification of ecosystem services proposed by COSTANZA et al. (1997). The estimated annual value of ecosystem services in the study area was 7.3×109US$/a for the total area of 1 356 700ha, among which about 97% was provided by the wetlands. Effective conservation and management of wetlands are therefore crucial to Shanghai’s sustainable development. The limitations of the evaluation method for ecosystem service value were also discussed in the present paper. 展开更多
关键词 生态服务价值 地理信息系统 上海 经济评估 自然湿地
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A New Carbon and Oxygen Balance Model Based on Ecological Service of Urban Vegetation 被引量:6
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作者 YIN Kai ZHAO Qianjun +3 位作者 LI Xuanqi CUI Shenghui HUA Lizhong LIN Tao 《Chinese Geographical Science》 SCIE CSCD 2010年第2期144-151,共8页
The application of human induced oxygen consumption and carbon emission theory in urban region was summed up and on this base a new model of urban carbon and oxygen balance (UCOB) was constructed by calculating the ca... The application of human induced oxygen consumption and carbon emission theory in urban region was summed up and on this base a new model of urban carbon and oxygen balance (UCOB) was constructed by calculating the carbon and oxygen fluxes. The purpose was to highlight the role of vegetation in urban ecosystems and evaluate the effects of various human activities on urban annual oxygen consumption and carbon emission. Hopefully,the model would be helpful in theory to keep the regional balance of carbon and oxygen,and provide guidance and support for urban vegetation planning in the future. To test the UCOB model,the Jimei District of Xiamen City,Fujian Province,China,a very typical urban region,was selected as a case study. The results turn out that Jimei′s vegetation service in oxygen emission and carbon sequestration could not meet the demand of the urban population,and more than 31.49 times of vegetation area should be added to meet the whole oxygen consumption in Jimei while 9.60 times of vegetation area are needed to meet the carbon sequestration targets. The results show that the new UCOB model is of a great potential to be applied to quantitative planning of urban vegetation and regional eco-compensation mechanisms. 展开更多
关键词 城市植被 平衡模型 生态服务 碳排放 氧消耗 城市生态系统 生态补偿机制 人类活动
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EVALUATION OF ECOLOGICAL SERVICES OF JILIN PROVINCE, NORTHEAST CHINA 被引量:2
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作者 YUShu-xia SHANGJin-cheng GUOHuai-cheng 《Chinese Geographical Science》 SCIE CSCD 2004年第3期215-220,共6页
The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic... The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic solutions for ecological problems. The evaluation is based on the methods proposed by COSTANZA et al., and some modifications about unit value of forest and cropland system were made according to the real characters of ecosystem, climate, natural conditions etc., in Jilin Province. Total value of ecosystem services is about 554.404×109 yuan(RMB)/a, which is about 4.9 times of GDP of the corresponding period. The results of this study could be used as a fundamental work for the construction of ecological province, which was carried out from 2001, and could provide ecological information for decision-making. Furthermore, the necessities for the further studies on the evaluation of ecological services and natural capital were discussed. 展开更多
关键词 生态环境评价 GDP 国内生产总值 吉林
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Compensation for forest ecological services in China 被引量:1
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作者 Liu Can Wang Sen +1 位作者 Zhang Wei Liang Dan 《Forestry Studies in China》 CAS 2007年第1期68-79,共12页
The paper discusses methods to compensate for the costs incurred in the supply of forest ecological services (FES), i.e. government dominated and market-based instruments as well as progress made so far in China. Fact... The paper discusses methods to compensate for the costs incurred in the supply of forest ecological services (FES), i.e. government dominated and market-based instruments as well as progress made so far in China. Factors which constrain the supply of these services and potential policy improvements are presented. 展开更多
关键词 中国 森林生态服务 补偿机制 森林经济 林业政策
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The Ecological Service Function Development of Urban Modern Agriculture in Tianjin City and Corresponding Countermeasures
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作者 Jing QIN Guoxing SUN Jin LI 《Asian Agricultural Research》 2013年第3期26-29,共4页
Based on the current situation of ecological environment of agriculture in Tianjin City,we divide the ecological service function of urban modern agriculture in Tianjin City into seven types: air regulation,climate re... Based on the current situation of ecological environment of agriculture in Tianjin City,we divide the ecological service function of urban modern agriculture in Tianjin City into seven types: air regulation,climate regulation,water conservation,soil formation and protection, waste disposal,biodiversity conservation,and ecological entertainment. According to the method for assessing the value of natural ecosystem, coupled with the ecological service value equivalency factor table of China's ecosystem formulated by domestic scholars,we estimate the ecological value in Tianjin City. The results show that the actual ecological value of agriculture in Tianjin City was 30. 752 billion yuan in 2010,close to the agricultural economic value ( 31. 733 billion yuan) in 2010. Finally we put forth the following countermeasures for the ecological function development of urban modern agriculture in Tianjin City: strictly protecting arable land,and raising the standards of compensation for agricultural land requisition; actively and prudently developing facility agriculture,and preventing the blind scale expansion of facility agriculture to better give play to its ecological function; strengthening the construction of ecological agriculture,and promoting the market conversion of the ecological service value of agriculture; improving the environment,to form relatively complete agro-ecological system. 展开更多
关键词 TIANJIN City Urban MODERN AGRICULTURE ecological s
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Ecological service! Respect or destroy?
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作者 LI Meng-lin MA Wen-qiu ZHOU Run-ze 《Ecological Economy》 2019年第3期174-179,共6页
The issue on environmental degradation has always been one of very serious ecological and socially economic problems in the world.Economic theory often ignores the impact of its decisions on the environment.However,th... The issue on environmental degradation has always been one of very serious ecological and socially economic problems in the world.Economic theory often ignores the impact of its decisions on the environment.However,the environment often provides ecosystem services to sustain human health and build one sustainable environment.Therefore,it is important to propose an appropriate solution for estimating the environmental costs of land use.According to the research scale,the ecological service value model is divided into two parts,namely the large-and medium-sized land project ecosystem service value model.Then,these two models will be discussed in the medium-sized urbanization development project,and large-scale national high-speed rail project,respectively. 展开更多
关键词 ecological service ECOSYSTEM services land use environmental COST
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Evaluation on Cultivated Land Resource Ecological Service Value in Wuhan Metropolitan Area
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作者 Jinhua TANG Yinghui LI +2 位作者 Gangqiang CHEN Lei YU Sujuan LI 《Agricultural Science & Technology》 CAS 2014年第10期1809-1811,1832,共4页
The land ecosystem service function value contains the gas regulating function value, air purification function value, water conservation value, land conservation value, soil nutrient conservation value and maintain b... The land ecosystem service function value contains the gas regulating function value, air purification function value, water conservation value, land conservation value, soil nutrient conservation value and maintain biodiversity value. Based on the method of market value and the data of Hubei Statistical yearbook, cultivated land resources of ecosystem service function value is 730 038.69 Million in 2007-2009, and 714 774.99 Million in 2010-2012 in Wuhan Metropolitan Area. After three years of development, Wuhan Metropolitan Area of ecological value of cultivated land has increased by about 3.97%. From the point of each composition, the importance of gas regulating function of cultivated land resources and water conservation function is the forefront. From the point of spatial distribution, the highest of annual average value of the cultivated land ecological was Huanggang(1.725 billion yuan), the lowest was Ezhou(217.868 6 million yuan) in 2010-2012. From the point of space changes, the land ecological value increased only in Qianjiang city,while farmland ecological value in other cities was falling The conclusion is of directive significance to the regional land protection policy and the farmland reasonable distribution, for Wuhan Metropolitan Area and other areas. 展开更多
关键词 生态系统服务 武汉城市圈 功能价值 耕地资源 土地资源 评价 生态价值 生物多样性
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A Study on Forest Species Diversity and Its Ecological Service Function in the Plateau Area of Western Sichuan
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作者 Deng Yu-lin, Wang Yu-kuan, Peng Pei-haoInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期975-980,共6页
This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendenc... This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendency to increase and that its ecological service function is to be improved with stand age growing. The species diversity in forest communities is also gradually increased on different succession stage till reaching a climax level. But the species diversity in the climax community is slightly decreased before it reaches a relatively constant status. Ecological service function of diversity is gradually strengthened with the progress of succession. In addition, species diversity in a stand in a similar site and at a same age differs among forest types. Species diversity index within a coniferous and broad-leaved mixed forest is larger than that within a coniferous forest. Meanwhile, species diversity enriches as the tree density increases. 展开更多
关键词 四川 高原地区 森林 生物多样性
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Chinese Policies and Practices regarding Payments for Ecological Services in Watersheds
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作者 Liu Guihuan Zhang Huiyuan Wan Jun 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第1期36-43,共8页
Watersheds provide a variety of ecological services including soil and water conservation, carbon sequestration and biodiversity protection. However, activities in a fast-growing economy significantly impact the suppl... Watersheds provide a variety of ecological services including soil and water conservation, carbon sequestration and biodiversity protection. However, activities in a fast-growing economy significantly impact the supply and demand of these watershed services. To mitigate these impacts, the concept of payment for environmental and ecosystem services from water-sheds has emerged in global academic and policy circles. The governments and academic communities in China have increas-ingly described payments for ecological services from watersheds with the concept of watershed eco-compensation as it is urgent to protect watershed ecosystems. Watershed eco-compensation has proved to be one of the most economically effective means of solving environmental problems of watersheds to be adopted by the Chinese government. This paper presents an objective analysis of the Chinese market for watershed ecosystem services, including supply and demand for the services. It also summarizes Chinese policies on watershed eco-compensation, including relevant laws and regulations and fiscal policies. In addition, it presents a re-view of Chinese practices in watershed eco-compensation, in-cluding the analysis of an ecological construction project in West-ern China, inter-provincial watershed eco-compensation practices and plans, and payment for ecological services at the provincial and small watershed levels. Finally, it summarizes the key com-ponents of the process of payment in Chinese watershed eco-compensation. This discussion forms the basis of concluding suggestions for ecosystem services compensation and ecological protection in the large scale river basin. 展开更多
关键词 中国 生态环境 临界经济补偿 政策 实践 环境经济学
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Ecological service assessment of human-dominated freshwater ecosystem with a case study in Yangzhou Prefecture, China 被引量:5
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作者 YEYa-ping WANGRu-song RENJing-ming HUDan YUANShao-jun WANGMin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期755-761,共7页
Freshwater ecosystems provide a host of services to humanity. These services are now rapidly being lost, not least because of the inability of making the impacts measurable. To overcome this obstacle, assessment frame... Freshwater ecosystems provide a host of services to humanity. These services are now rapidly being lost, not least because of the inability of making the impacts measurable. To overcome this obstacle, assessment frameworks for freshwater ecosystem services are needed. A simple water equivalent framework to assess the ecological services provided by freshwater ecosystems was developed in this study. It translated the occupation of freshwater ecosystem services into biologically freshwater volumes and then compares this consumption to the freshwater throughput, that is, the ecological capacity available in this region. In this way, we use the example of Yangzhou Prefecture, to account the main categories of human occupation of water ecosystem services. The result showed that there is a huge gap between the consumption and the supply of freshwater ecosystem services. This must encourage local government to make land-use and water management decisions both economically rational and environmentally sound. 展开更多
关键词 生态学 生态系统 扬州市 环境保护 水体
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Urban spatial expansion and its impact on ecological service values of Chongqing City Proper in the last 30 years 被引量:3
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作者 涂建军 Xiang Xinyi Yang Le 《High Technology Letters》 EI CAS 2013年第2期162-169,共8页
Based on the remote sensing images of urban land use of Chongqing City Proper in the last 30years(from 1978 to 2011),The paper focuses on the impact of urban spatial expansion on urban ecosystem service.The charactere... Based on the remote sensing images of urban land use of Chongqing City Proper in the last 30years(from 1978 to 2011),The paper focuses on the impact of urban spatial expansion on urban ecosystem service.The charactereristics of urban spatial expansion pattern are expressed by Landscape Expansion Index and Index of Fractal Dimension.Taking advantage of calculation of these two indices,changes of the ecological service values in the main urban area of Chongqing caused by the variation of urban expansion patterns are evaluated and the interrelationship is analyzed.The main conclusions and results are as follows;in Chongqing City Proper,the ecological service value decreased rapidly from 1978 to 2011,especially in the period of 2002-2011.Urban spatial expansion pattern has exerted significant impact on urban ecosystem service value.Edge-expansion pattern broke into a great deal of urban enclaves and caused the disadvantage effect of the function of urban ecological system.At the same time,negative correlation existed between the indices of fractal dimension and the ecosystem service value. 展开更多
关键词 城市空间扩展 生态服务价值 重庆市 生态系统服务价值 城市土地利用 城市生态系统 分形维数 重庆主城区
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The coordinated evolution of ecological environment,public service,and tourism economy along the Silk Road Economic Belt,using the Dual-Carbon Targets
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作者 Shuo Yang Wei Guo +1 位作者 Tianjun Xu Tongtong Liu 《Chinese Journal of Population,Resources and Environment》 2024年第1期34-47,共14页
Carbon peak and carbon neutrality(dual-carbon)are important targets for the international response to climate change.The Silk Road Economic Belt is a strategic resource region and is important for future ecological en... Carbon peak and carbon neutrality(dual-carbon)are important targets for the international response to climate change.The Silk Road Economic Belt is a strategic resource region and is important for future ecological environment and tourism development.Based on the“dual-carbon”targets,the Single index quantification,Multiple index synthesis,and Poly-criteria integration evaluation model were used in this study to measure the coordinated development index of the ecological environment,public service,and tourism economy along the Silk Road Economic Belt and to analyze its spatial and temporal evolution.Further,it explores the dynamic evolution and development trend of the three systems using the Kernel Density and Grey Markov Prediction Model.The results show that the coordinated development index along this region needs to be improved during the study period.Furthermore,the coordinated development index of the Southwest region is relatively higher than that of the Northwest region.From the development trend of the three systems,all of them develop in a stable manner;however,the tourism economy system is easily affected by external disturbances.The coordinated development index of the three systems changes dynamically and tends to be in a good state of coordination.There is a certain spatial and temporal heterogeneity.The gravity center of the coordinated development index has been in the Southwest region.During the forecast period,the coordinated development index along this region will improve significantly,while insufficient and unbalanced development will continue. 展开更多
关键词 Dual-carbon ecological environment Public services Tourist economy Silk Road Economic Belt
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Ecosystem Service Value Assessment of Wutong Mountain Rhododendron moulmainense Ecological Landscape Forest in Shenzhen City in 2021
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作者 Rui CONG Kaiwen ZHANG +1 位作者 Xiaodan CHEN Dingyue WANG 《Agricultural Biotechnology》 CAS 2023年第4期88-92,共5页
Taking Wutong Mountain Rhododendron moulmainense ecological landscape forest in Shenzhen City as an example,the value of the forest was assessed by constructing an ecological service value assessment system and accoun... Taking Wutong Mountain Rhododendron moulmainense ecological landscape forest in Shenzhen City as an example,the value of the forest was assessed by constructing an ecological service value assessment system and accounting method.The assessment results showed that the total ecosystem service value of R.moulmainense ecological landscape forest was 13.195 billion yuan,and the top three services included the value of forestry products,the value of biodiversity maintenance and the value of leisure and recreation,indicating that the ecosystem service of Wutong Mountain R.moulmainense ecological landscape forest in Shenzhen has great ecological and economic value,especially in forestry products,biodiversity maintenance,and leisure and recreation. 展开更多
关键词 Wutong Mountain Rhododendron moulmainense ecological landscape forest Ecosystem services Value assessment
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Ecological problems and ecological restoration zoning of the Aral Sea
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作者 BAO Anming YU Tao +7 位作者 XU Wenqiang LEI Jiaqiang JIAPAER Guli CHEN Xi Tojibaev KOMILJON Shomurodov KHABIBULLO Xabibullaev B SAGIDULLAEVICH Idirisov KAMALATDIN 《Journal of Arid Land》 SCIE CSCD 2024年第3期315-330,共16页
The Aral Sea was the fourth largest lake in the world but it has shrunk dramatically as a result of irrational human activities, triggering the "Aral Sea ecological crisis". The ecological problems of the Ar... The Aral Sea was the fourth largest lake in the world but it has shrunk dramatically as a result of irrational human activities, triggering the "Aral Sea ecological crisis". The ecological problems of the Aral Sea have attracted widespread attention, and the alleviation of the Aral Sea ecological crisis has reached a consensus among the five Central Asian countries(Kazakhstan, Uzbekistan, Tajikistan, Kyrgyzstan, and Turkmenistan). In the past decades, many ecological management measures have been implemented for the ecological restoration of the Aral Sea. However, due to the lack of regional planning and zoning, the results are not ideal. In this study, we mapped the ecological zoning of the Aral Sea from the perspective of ecological restoration based on soil type, soil salinity, surface water, groundwater table, Normalized Difference Vegetation Index(NDVI), land cover, and aerosol optical depth(AOD) data. Soil salinization and salt dust are the most prominent ecological problems in the Aral Sea. We divided the Aral Sea into 7 first-level ecological restoration subregions(North Aral Sea catchment area in the downstream of the Syr Darya River(Subregion Ⅰ);artificial flood overflow area in the downstream of the Aral Sea(Subregion Ⅱ);physical/chemical remediation area of the salt dust source area in the eastern part of the South Aral Sea(Subregion Ⅲ);physical/chemical remediation area of severe salinization in the central part of the South Aral Sea(Subregion Ⅳ);existing water surface and potential restoration area of the South Aral Sea(Subregion Ⅴ);Aral Sea vegetation natural recovery area(Subregion Ⅵ);and vegetation planting area with slight salinization in the South Aral Sea(Subregion Ⅶ)) and 14 second-level ecological restoration subregions according to the ecological zoning principles. Implementable measures are proposed for each ecological restoration subregion. For Subregion Ⅰ and Subregion Ⅱ with lower elevations, artificial flooding should be carried out to restore the surface of the Aral Sea. Subregion Ⅲ and Subregion Ⅳ have severe salinization, making it difficult for vegetation to grow. In these subregions, it is recommended to cover and pave the areas with green biomatrix coverings and environmentally sustainable bonding materials. In Subregion Ⅴ located in the central and western parts of the South Aral Sea, surface water recharge should be increased to ensure that this subregion can maintain normal water levels. In Subregion Ⅵ and Subregion Ⅶ where natural conditions are suitable for vegetation growth, measures such as afforestation and buffer zones should be implemented to protect vegetation. This study could provide a reference basis for future comprehensive ecological management and restoration of the Aral Sea. 展开更多
关键词 ecological restoration zoning salt and dust storms soil salinization ecological crisis Aral Sea Central Asia
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Characterization of Wastewater in School Environments for an Ecological Treatment Solution: A Case Study of Ndiebene Gandiol 1 School
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作者 Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye Deme 《Journal of Water Resource and Protection》 CAS 2024年第1期27-40,共14页
The study conducted at Ndiebene Gandiol 1 school in Senegal has unveiled serious environmental and public health challenges. The wastewater analysis revealed high levels of Biochemical Oxygen Demand (BOD5), Chemical O... The study conducted at Ndiebene Gandiol 1 school in Senegal has unveiled serious environmental and public health challenges. The wastewater analysis revealed high levels of Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and fecal coliforms, signaling potential risks to the well-being of students and staff. This situation mirrors a wider issue in rural educational settings, where inadequate sanitation persists. Intensive wastewater treatment options are known for their effectiveness against high pollutant loads but are resource-intensive in both energy and cost. Conversely, extensive treatment systems, while requiring more land, provide a sustainable alternative by harnessing natural processes for pollutant removal. The research suggests a hybrid treatment approach could serve the school’s needs, balancing the robust capabilities of intensive methods with the ecological benefits of extensive systems. Such a solution would need to be tailored to the specific environmental, financial, and logistical context of the school, based on comprehensive feasibility studies and stakeholder engagement. This study’s findings underscore the urgency of addressing sanitation in schools, as it is intrinsically linked to the health and academic success of students. Quick, effective, and long-term strategies are vital to secure a healthier and more prosperous future for the youth. With proper implementation, the school can transform its sanitation facilities, setting a precedent for rural educational institutions in Senegal and similar contexts globally. 展开更多
关键词 Wastewater Characterization ecological Treatment School Sanitation PHYTOREMEDIATION Rural Infrastructure Environmental Health
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Deep Reinforcement Learning-Based Task Offloading and Service Migrating Policies in Service Caching-Assisted Mobile Edge Computing
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作者 Ke Hongchang Wang Hui +1 位作者 Sun Hongbin Halvin Yang 《China Communications》 SCIE CSCD 2024年第4期88-103,共16页
Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and energy.... Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and energy.Due to the homogeneity of request tasks from one MWE during a longterm time period,it is vital to predeploy the particular service cachings required by the request tasks at the MEC server.In this paper,we model a service caching-assisted MEC framework that takes into account the constraint on the number of service cachings hosted by each edge server and the migration of request tasks from the current edge server to another edge server with service caching required by tasks.Furthermore,we propose a multiagent deep reinforcement learning-based computation offloading and task migrating decision-making scheme(MBOMS)to minimize the long-term average weighted cost.The proposed MBOMS can learn the near-optimal offloading and migrating decision-making policy by centralized training and decentralized execution.Systematic and comprehensive simulation results reveal that our proposed MBOMS can converge well after training and outperforms the other five baseline algorithms. 展开更多
关键词 deep reinforcement learning mobile edge computing service caching service migrating
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Ecological network analysis reveals complex responses of tree species life stage interactions to stand variables
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作者 Hengchao Zou Huayong Zhang Tousheng Huang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期29-43,共15页
Tree interactions are essential for the structure,dynamics,and function of forest ecosystems,but variations in the architecture of life-stage interaction networks(LSINs)across forests is unclear.Here,we constructed 16... Tree interactions are essential for the structure,dynamics,and function of forest ecosystems,but variations in the architecture of life-stage interaction networks(LSINs)across forests is unclear.Here,we constructed 16 LSINs in the mountainous forests of northwest Hebei,China based on crown overlap from four mixed forests with two dominant tree species.Our results show that LSINs decrease the complexity of stand densities and basal areas due to the interaction cluster differentiation.In addition,we found that mature trees and saplings play different roles,the first acting as“hub”life stages with high connectivity and the second,as“bridges”controlling information flow with high centrality.Across the forests,life stages with higher importance showed better parameter stability within LSINs.These results reveal that the structure of tree interactions among life stages is highly related to stand variables.Our efforts contribute to the understanding of LSIN complexity and provide a basis for further research on tree interactions in complex forest communities. 展开更多
关键词 Tree interactions Life stages Interaction networks ecological complexity
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Utilization of recycled solid waste as ecological reclamation materials based on plant growth experiments and soil quality analysis
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作者 QIN Xiaochun NI Anchen +2 位作者 YANG Dongxiao XING Wenhu LIU Shiliang 《Journal of Mountain Science》 SCIE CSCD 2024年第3期820-834,共15页
During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil could not be rationally utilized.Besides,the vegetation recovery is slow in the spoil areas d... During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil could not be rationally utilized.Besides,the vegetation recovery is slow in the spoil areas due to the soil depletion.Aiming at recycling the solid waste,the sieved engineering waste slag with local red clay and corn straw biochar was supplied to solve the problem of insufficient nutrients in engineering waste slag and soil.In addition,planting experiments of alfalfa(Medicago sativa L.)and Amorpha fruticosa L.combined with physical and chemical experiments were carried out to prove the feasibility of the novel improved substrate for the reclamation of spoil areas.The results show that the substrate's improvement effect is mainly affected by the soil to slag ratio and the biochar content.The improvement effect of soil matrix in highway spoil area decreases with the increase of the waste slag content,especially when the soil-slag ratio is less than 3,and the promotion of plants is limited.On the contrary,the improvement effect is proportional to the biochar content(3%-8%).But it is noted that the Cu and Pb in the soil will exceed the clean limit corresponding to the Nemero soil pollution index level when the biochar content is 8%.Therefore,it is recommended that the soil-slag ratio should be≥3,and the biochar content should reach 3%-5%.This research provides experimental basis and technical support for utilizing solid waste resources in the reclamation of highway spoil areas. 展开更多
关键词 HIGHWAY Spoil area Waste slag Modified soil ecological reclamation
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Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China
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作者 HU Bo WEN Qingke +3 位作者 XI Fengjiang LI Mengyao WANG Libing REN Yuejuan 《Chinese Geographical Science》 SCIE CSCD 2024年第1期67-78,共12页
Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local ... Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local governments.However,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration policies.Therefore,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to 2021.The results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland growth.Using the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to 2021.Compared to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 t.The livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in 2015.During the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown steadily.Per capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in 2021.Relying on grassland resources to develop the pastoral ecology also broadens the potential economic development space.Overall,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s development from both an ecological and economic perspective.With the support of scientific evidence,enclosure policy can be extended to more than 110 000 km~2 of grasslands in northern China with similar precipitation and temperature conditions,enhancing the productive and ecological potential of grasslands.The above research results will contribute to the scientific formulation of grassland pasture quality improvement plans in northern China. 展开更多
关键词 ENCLOSURE GRASSLAND ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China
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Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China 被引量:1
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作者 Jin Hu HaiBing Ruan +2 位作者 FuQing Huang ShengYang Gu XianKang Dou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期400-407,共8页
The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of G... The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions. 展开更多
关键词 International GNSS service(IGS)Global Ionosphere Maps(GIM) Crustal Movement Observation Network of China(CMONOC) total electron content(TEC) data assessment
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