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生态地境和状态-转换模型的研究综述 被引量:2
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作者 乌兰 韩国栋 +1 位作者 乔江 袁清 《中国草地学报》 CSCD 北大核心 2014年第3期90-97,共8页
阐述了生态地境与状态-转换模型的理论发展及构建方法,并以实例说明其构建过程以及在国内外不同生态系统的应用情况,探讨了生态地境在我国草原管理应用中存在的问题以及对策,以期为草地资源的科学管理与可持续发展提供参考。
关键词 生态地境 状态-转换模型 构建方法 问题及对策
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生态地境划分对新疆草原生态建设的影响探讨 被引量:1
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作者 双胡尔 魏鹏 顾祥 《安徽农业科学》 CAS 2017年第25期75-76,82,共3页
阐述了国内外生境划分对草原生态建设影响的研究进展,分析了新疆草地资源现状,提出了划分生态地境及合理利用草原的建议。
关键词 生态地境 草地资源 家庭牧场
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Research on Ecological Regionalization of Inland Lake Wetland of Bashang in Hebei Province 被引量:1
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作者 张茹春 阳小兰 +3 位作者 高士平 陈辉 王瑞君 蒋红军 《Agricultural Science & Technology》 CAS 2010年第8期125-128,144,共5页
An ecological regionalization index system was established for Bashang inland lake wetland based on ecological and environmental factors,with landform,geomorphy,vegetation types and climate as primary indices,micro-la... An ecological regionalization index system was established for Bashang inland lake wetland based on ecological and environmental factors,with landform,geomorphy,vegetation types and climate as primary indices,micro-landform,vegetation type,soil type,climate,ecosystem types,wetland features and human activities as secondary indices. Based on these index systems,the area was divided into three eco-environment regions and nine sub eco-environment regions. An eco-regional map of Bashang inland lake wetland was drawn by using GIS. The ecological characteristics,existing problems and control measures of each region were described. This study will supply guidance for the construction of local ecological environment and regulation of industrial structure,promoting sustainable development of Bashang inland lake wetland. 展开更多
关键词 Ecological regionalization ECO-ENVIRONMENT Bashang wetland
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Influence of Soil Geochemistry to the Quality of Winter Jujube in Zhanhua 被引量:1
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作者 高宗军 王敏 +1 位作者 庞绪贵 刘中业 《Agricultural Science & Technology》 CAS 2010年第9期209-212,216,共5页
[Objective] The aim was to investigate the effects of soil geochemistry on the quality of winter jujube.[Method]Based on the data of ecological geochemical survey in lower Yellow River Basin,the relevance of the geoch... [Objective] The aim was to investigate the effects of soil geochemistry on the quality of winter jujube.[Method]Based on the data of ecological geochemical survey in lower Yellow River Basin,the relevance of the geochemistry environment in top soils and the quality of winter jujubes was analyzed.[Result]Cd,Ni and other heavy metals in the soil more obviously affected the nutrition of winter jujubes.[Conclusion]B,Mn,MgO,Cd,Zn,K2O and other elements in the root soil played an important role in the enrichment of Cr and Hg of winter jujube fruit.And the absorption of heavy metals in winter jujube root could be interfered by improving fertilization method,to reduce the enrichment of harmful elements in jujube fruit. 展开更多
关键词 Zhanhua winter jujube Ecological geochemical environment Heavy metal element
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Analysis on Ecological Benefits of Urban Wetlands and Protection Measures with a Case of Nansha Wetland 被引量:1
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作者 林志浩 庞衍松 +6 位作者 许锐聪 刘琪帅 黄李茂 林益嘉 韩西伦 纪楚滨 刘敬勇 《Agricultural Science & Technology》 CAS 2015年第3期587-589,共3页
Nansha wetland plays a crucial role in ecological balance of the Pearl River Delta or even Guangzhou. The research, based on researches available, analyzed ecological benefits of Nansha wetland and proposed protection... Nansha wetland plays a crucial role in ecological balance of the Pearl River Delta or even Guangzhou. The research, based on researches available, analyzed ecological benefits of Nansha wetland and proposed protection measures in order to better protect urban wetlands and achieve sustainable development of ecological resources of Nansha wetland. 展开更多
关键词 Urban wetland Nansha district Ecological benefits Environment protection
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Eco-Environment Status of the Bohai Bay and the Impact of Coastal Exploitation 被引量:3
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作者 聂红涛 陶建华 《Marine Science Bulletin》 CAS 2009年第2期81-96,共16页
With the rapid economic development in the surrounding coastal zone, more and more wastewater has been discharged into the Bohai Bay. And with the scale of coastal exploitation being expanded year by year, the eco-env... With the rapid economic development in the surrounding coastal zone, more and more wastewater has been discharged into the Bohai Bay. And with the scale of coastal exploitation being expanded year by year, the eco-environment of the Bohai Bay has been confronted with great pressure. In this paper, the main problems in the eco-environment of the Bohai Bay were summarized firstly. Red tides occurred more frequently and more seriously; salinity rose in inshore area, the fishery resources degenerated; all the above indicate that the eco-environment of the Bohai Bay is under a severe situation Next, to make a concrete study of the existing status of the Bohai Bay, the eco-environment index system was set up. Then the principal components analytic method and grey relation method were adopted to carry on a comprehensive analysis on the status. The results show that serious pollution of inorganic nitrogen and active phosphate, and poor species diversity are the main presentations of the bad quality of the inshore aquatic eco-environment of the Bohai Bay, which is mainly induced by the massive discharge of pollutant from land and the overexploitation in the surrounding coastal zone. At last, the variations of hydrodynamic characteristics and the pollutant transport caused by coastal exploitations such as reclamation and seawater desalination are analyzed. The results show that reclamation in coastal water not only decreases the tidal prism and weakens the tidal current action, but also influences the pollution distribution in the coastal water. The seawater desalination project would cause tremendous influence to the aquatic eco-environment of the Bohai Bay as the pollutant's pulse impact. Much more attention would be paid to the reasonable use of the coastal zone resources and the control of pollution from land-based sources. 展开更多
关键词 Bohai Bay aquatic Eco-environment indicator system RECLAMATION seawater desalination
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Assessment of Land Comprehensive Carrying Capacity in Lin'an City
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作者 卢必慧 许红卫 《Agricultural Science & Technology》 CAS 2016年第12期2757-2762,共6页
According to regional characteristics and the actual situation in Lin ’an City, an evaluation index system of land comprehensive carrying capacity composed of three support subsystems (eco-environment, social and ec... According to regional characteristics and the actual situation in Lin ’an City, an evaluation index system of land comprehensive carrying capacity composed of three support subsystems (eco-environment, social and economic carrying capaci-ties) containing 22 evaluation indexes was established to evaluate the comprehen-sive carrying capacity of land resource in Lin’an City during 2005-2012. Meanwhile, based on the target data of overal land use plan, the level of land comprehensive carrying capacity was predicted at the end of the plan period (2020) .The results showed that land comprehensive carrying capacity had a significant growth in Lin ’an from 2005 to 2012, and the development trend was basical y sustainable. The sub-systems also had been greatly improved, in which the constant improvement of ec-ological environment carrying capacity made the largest contribution to the constant raising of land comprehensive carrying capacity. The degree of coordination between the systems was poor, in which eco-environment carrying capacity had the maxi-mum growth, far more than the social and economic carrying capacities. According to the land comprehensive carrying capacity in 2020, utilization of land resources in Lin&#39;an city can achieve sustainable development in general. Final y, proposals of im-proving comprehensive carrying capacity were put forward in terms of the enhance-ment of eco-environment protection, accelerating economic development and policy guidance. 展开更多
关键词 Land comprehensive carrying capacity Eco-environment carrying capac-ity Planning goal Lin&#39 an city
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Eco-Environmental Vulnerability Evaluation in the Yellow River Basin,China 被引量:53
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作者 WANG Si-Yuan LIU Jing-Shi YANG Cun-Jian 《Pedosphere》 SCIE CAS CSCD 2008年第2期171-182,共12页
Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,China.The objective of this study was to improve our under... Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,China.The objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be established.An environmental numerical model was developed using spatial principal component analysis(SPCA)model.The model contains twelve factors that include variables of land use,soil erosion,topography,climate,and vegetation.Using this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2000 for the Yellow River Basin.The SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2000 were analyzed and the driving factors of eco-environmental changes were investigated.The results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the whole.However,the eco-environmental quality had become worse over the ten years in some regions.In the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years. 展开更多
关键词 eco-environmental vulnerability geographic information system (GIS) remote sensing (RS) spatial principal component analysis Yellow River Basin
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LAND COVER CHANGES AND LANDSCAPE DYNAMICS ASSESSMENT IN LOWER REACHES OF TARIM RIVER IN CHINA 被引量:9
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作者 WUXiu-qin CAIYun-long 《Chinese Geographical Science》 SCIE CSCD 2004年第1期28-33,共6页
The Tarim River Basin, located in the typical arid region, is one of the key regions of LUCC research in China and plays an important role in maintaining the sustainable development of the western China. In recent yea... The Tarim River Basin, located in the typical arid region, is one of the key regions of LUCC research in China and plays an important role in maintaining the sustainable development of the western China. In recent years,the ecological environment of the Tarim River Basin has degraded greatly. In the lower reaches, in particular, the riverbed has been dried up for more than 20 years, which accelerated the desertification and has been a great threat to people′s lives. Taking the section of the Tarim River between Qiala Lake and Taitema Lake as a typical region, an investigation on land cover changes was carried out with the support of remote sensing information of 1988 and 2000 respectively. The changes of land cover in this region were obtained: 1) Cropland tended to increase. 2) Urban or Built-up Area in 2000 was 324.4ha more than that in 1988. 3) Waters expanded by 3476.51ha. 4) Woodland and Grassland decreased, while Barren Land increased by 3824.9ha. The total amount of land use/land cover change between 1988 and 2000 is small,which is only 0.355% of the total area. It shows that the developmental pace of the lower reaches of the Tarim River is relative slow. Based on these results, the authors assessed the landscape dynamics of this region and pointed out that the degree of desertification was strengthened and the landscape dominated by sand land was further characterized by salt desert. 展开更多
关键词 Tarim River LUCC landscape evaluation landscape ecological indices
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Estimation of Ecological Water Requirements Based on Habitat Response to Water Level in Huanghe River Delta,China 被引量:7
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作者 CUI Baoshan HUA Yanyan +3 位作者 WANG Chongfang LIAO Xiaolin TAN Xuejie TAO Wendong 《Chinese Geographical Science》 SCIE CSCD 2010年第4期318-329,共12页
In recent years,wetland ecological water requirements (EWRs) have been estimated by using hydrological and functional approaches,but those approaches have not yet been integrated for a whole ecosystem.This paper prese... In recent years,wetland ecological water requirements (EWRs) have been estimated by using hydrological and functional approaches,but those approaches have not yet been integrated for a whole ecosystem.This paper presents a new method for calculating wetland EWRs,which is based on the response of habitats to water level,and determines water level threshold through the functional integrity of habitats.Results show that in the Huanghe (Yellow) River Delta water levels between 5.0 m and 5.5 m are required to maintain the functional integrity of the wetland at a value higher than 0.7.One of the dominant plants in the delta,Phragmites australis,tolerates water level fluctuation of about ± 0.25 m without the change in wetland functional integrity.The minimum,optimum and maximum EWRs for the Huanghe River Delta are 9.42×106 m3,15.56×106 m3 and 24.12×106 m3 with water levels of 5.0 m,5.2 m and 5.5 m,corresponding to functional integrity indices of 0.70,0.84 and 0.72,respectively.A wetland restoration program has been performed,which aims to meet these EWRs in attempt to recover from losses of up to 98% in the delta's former wetland area. 展开更多
关键词 water level-habitat response functional integrity ecological water requirements WETLAND Huanghe River Delta
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A review of soil and water conservation in China 被引量:1
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作者 张兴昌 邵明安 +2 位作者 李世清 Peng Keshan 《Journal of Geographical Sciences》 SCIE CSCD 2004年第3期259-274,共16页
The preservation and sustainable development of soil and water resources isone of the basic principles for the development of China. Throughout the course of history, all thesocial improvement and economic development... The preservation and sustainable development of soil and water resources isone of the basic principles for the development of China. Throughout the course of history, all thesocial improvement and economic development are deeply concerned with soil loss and ecologicalenvironmental protection. It is now a common sense that soil and water conservation is the safetyinsurance for national ecology and its development. For the past long period of time, soil and waterloss has been recognized as 'the No.1 killer' to the ecological environment. The nation is on thestags of the critical conditions for its development. China has massive mountain and upland areawith complicated geological conditions and accelerated human destruction and serious soil and waterloss. Based on rich historical documents, renovating experience and detailed analysis of the datacollected in field experiments and field surveys for soil and water conservation, this paper aims toreview the general characteristics of soil and water loss, to explore the relationship between soiland water conservation and sustainable economic development, and to provide relevant strategies forsoil and water conservation in China. 展开更多
关键词 soil and water conservation ecological security ecological construction China
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Design and Applications of Land Resources and Ecological Environment Information System: A Case Study of Zigui County in the Three Gorges Area of China 被引量:25
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作者 ZHOUYONG WANGSHANQIN +1 位作者 DONGYUANHUA YANGLINZHANG 《Pedosphere》 SCIE CAS CSCD 2002年第4期373-381,共9页
The design and applications of a land information system built upon ARC/INFO and ArcView are presented. The proposed system not only maintains all the advantages of the more conventional implementations but also enhan... The design and applications of a land information system built upon ARC/INFO and ArcView are presented. The proposed system not only maintains all the advantages of the more conventional implementations but also enhances them in the following ways: 1) the application program interfaces (API) are used to transmit data and messages among different parts of the system; 2) the integrated system can support studies on land evaluations and ecological analyses by efficient management of attribute and spatial data and 3) correspondingly, spatial records and attributive records are linked by the same identifiers (ID). A case study application in Zigui County of the Three Gorges Area in China demonstrates that the system could employ land-use maps and land property data to predicate and analyze the land utilization changes in the past, present and future. The ecological environment analysis can be carried out with the data of land, economics and terrain map used, showing that the system can be widely applied, especially to survey land and environment resources in the countryside area. 展开更多
关键词 attribute database ecological environment land resources spatial database
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STATUS, CAUSES AND COMBATING SUGGESTIONS OF SANDY DESERTIFICATION IN QINGHAI-TIBET PLATEAU 被引量:4
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作者 LIU Yi-hua DONG Guang-rong +1 位作者 LI Sen DONG Yu-xiang 《Chinese Geographical Science》 SCIE CSCD 2005年第4期289-296,共8页
The Qinghai-Tibet Plateau is one of the major sandy desertification regions of China. Based on the recent investigation on sandy desertification, this paper analyses the status such as the type, area, distribution and... The Qinghai-Tibet Plateau is one of the major sandy desertification regions of China. Based on the recent investigation on sandy desertification, this paper analyses the status such as the type, area, distribution and damage of sandy land desertification in the plateau. Through the analysis on the factors affecting sandy desertification in the region’s natural and socio-economic systems as well as the processes and their interrelations, it can be concluded that sandy desertification in the Qinghai-Tibet Plateau resulted from the combined actions of normal natural sand drift processes, natural sandy desertification processes caused by climatic changes and man-made sandy desertification caused by improper human activities. In addition, it also predicts the possible developmental trend including the increase in desertification area and the enhancement in desertification developmental degree with the exacerbation of the complex processes, and finally puts forward some strategic suggestions to combat sandy desertification in the coming years. 展开更多
关键词 Qinghai-Tibet Plateau sandy desertification desertification control
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Eco-geographic Environment and Regional Development in Xinjiang of China 被引量:2
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作者 XIA Fuqiang DAI Erfu +2 位作者 ZHENG Du WU Shaohong YANG Qinye 《Chinese Geographical Science》 SCIE CSCD 2010年第1期74-83,共10页
The study on relationship between eco-geographic environment (EGE) and regional development (RD) is of theoretical and practical significance to promote the comprehensive study on nature and human factors and regi... The study on relationship between eco-geographic environment (EGE) and regional development (RD) is of theoretical and practical significance to promote the comprehensive study on nature and human factors and regional coordination development. Based on the evaluation index system and models of EGE and RD, Quadrant Analysis Method (QAM) and the Coordination Degree and Coordinated Development Degree Model (CDCDDM) were applied to studying the relationship between EGE and RD in Xinjiang in this paper. The results show that Xinjiang can be divided into four type regions according to the relationship between EGE and RD, namely high coordination region (HCR), overloading development region (ODR), low coordination region (LCR) and potential development region (PDR). Most areas of Xinjiang belong to LCR which can not bear a larger population and support large-scale economic development. HCR, ODR and PDR, which are mainly distributed in piedmont oases and take basin as unit, should be focused on in the development of Xinjiang. The EGE has great influence on RE), and there is serious contradiction between them. Relevant suggestions on development strategies were put forward according to the character of different type regions, and the key regions of macro-layout of RD in Xinjiang were pointed out. 展开更多
关键词 eco-geographic environment regional development harmonious degree XINJIANG
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Changes in Land Use and Agricultural Production Structure Before and After the Implementation of Grain for Green Program in Western China–Taking Two Typical Counties as Examples 被引量:6
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作者 ZHOU Ping WEN An-bang +4 位作者 YAN Dong-chun SHI Zhong-lin GUO Jin JU Zhan-sheng ZHANG Yi-lan 《Journal of Mountain Science》 SCIE CSCD 2014年第2期526-534,共9页
Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program(GGP), which was launched in 1999, aims to reduce soil... Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program(GGP), which was launched in 1999, aims to reduce soil and water loss and alleviate the ecological environment problem in western China. Two typical counties in western China, the Zhongxian(in Chongqing Municipality) and Ansai(in Shaanxi Province) were chosen to evaluate the dynamic changes of land use and agricultural production structure before and after the implementation of the Program in this paper. The results showed that the cultivated land area was reduced by 7.08% from 1989 to 2003. The cultivated land per person was decreased by 8.42% during 1999-2003. Moreover, the stability index of the secondary sector of the economy was increased from 0.91 in the period 1990-1999 to 0.94 in the following ten years. In addition, the stability index of tertiary economic sector increased from 0.88 to 0.92 in Zhongxian county. Meanwhile, the cultivated land area was reduced by 15.48% from 1990 to 1999. The soil erosion modulus was decreased by 33.33% from 1999 to 2006. Also, the stability index of secondary and tertiary economic sectors was 0.86 in the period 1998-2002. However, it decreased by 77% during 2002 to 2007 in Ansai County. These results imply that the Grain for Green Program had different impact on the two regions. Several effective strategies of soil and water conservation have been carried out to ameliorate the sustainable development of ecological environment and economy in these two counties of western China. 展开更多
关键词 Cultivated land Stability index Agricultural production structure Grain for Green Program (GGP) Three Gorges Reservoir region Loess Plateau
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SUSTAINABLE LAND USE PLANNING BASED ON ECOLOGICAL HEALTH——Case Study of Beiwenquan Town, Chongqing, China 被引量:6
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作者 SHAOJing-an WEIChao-fu XIEDe-ti 《Chinese Geographical Science》 SCIE CSCD 2005年第2期137-144,共8页
This paper, taking Beiwenquan Town of Beibei, Chongqing as an example, assessed the impacts of land use on ecological health by comprehensive index method, and discussed methodological system of sustainable land use p... This paper, taking Beiwenquan Town of Beibei, Chongqing as an example, assessed the impacts of land use on ecological health by comprehensive index method, and discussed methodological system of sustainable land use planning based on ecological health. Results indicated that: 1) From 1992 to 2002, land use changes focused on 12 patterns with the total conversion area of 92.11%, which were related to cultivated land, residential and industrial-mining area, and orchard land. Urbanization and economic reconstruction were the leading driving forces. 2) There was obvious difference of the areas of ecotypes driven by land use change in wide valley and mild slope between 1992 and 2002, while there were little or no difference in steep slope and very steep slope. 3) Both of the conditions of ecological health in 1992 and 2002 were sound, and the ecotypes focused on the types of health and sub-health. But, health ecosystem in 1992, with an area of 764.64ha, accounting for 38.51% of the total evaluation area, was better than that in 2002, with an area of 636.10ha, accounting for 34.19% of the total evaluation area. 4) The ecotypes involved into different ranges have already degenerated, due to humankind’s disturbance, while the conditions of ecological health in the same ranges in 1992, regardless of stability and reconstruction, were better than that in 2002. 5) The planning scenario based on ecological health was accorded with the practice condition of Beiwenquan Town: 388.29ha of cultivated land could meet the Beiwenquan demand of food and byproduct; 1045.26ha of forest land area, the Beiwenquan demand of ecological health; and 1004.73ha of the residential and industrial-mining area, the Beiwenquan building demand. 6) Sustainable land use planning based on ecological health had higher useful value, because it not only stood to ecological theory, but also satisfied the developmental demand of society and economy. 展开更多
关键词 ecological health land use ecological evaluation land supply and demand sustainable land use planning
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Preliminary Study on Early-warning System of Ecological Security in Water-Level-Fluctuating Zone (WLFZ) of Three Gorges Reservoir 被引量:2
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作者 郑磊 左太安 李月臣 《Agricultural Science & Technology》 CAS 2010年第5期159-164,共6页
The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological securit... The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological security dynamic monitoring,ecological security appraisal,ecological security forecast and ecological security decision-making management. The synthetic evaluation indicator system of the ecological security quality were initially established,which includes ecological environment pollution,land use and land cover change,geological hazard and epidemic outbreaks. At the same time,29 evaluating indicators were selected,divides into the basic factors,response factors and inducing factors,which need to be Real-time monitored. 展开更多
关键词 Ecological security Early warning system Fuzzy mathematics Three Gorges Reservoir Water-Level-Fluctuating Zone (WLFZ)
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CLOBAL CHARM OF THE CHANGJIANG RIVER DELTA 被引量:2
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作者 CHEN Shu-peng, ZHOU Cheng-hu,CHEN Qiu-xiao(State Key Laboratory of Resources & Environmental Information System, Chinese Academy of Sciences,Beijing 100101,P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2003年第4期289-299,共11页
Based on the theory of geo-economy,under the new situation of global economy,information network and China’s entry into WTO,also with the holding of APEC (in 2001) and the International Exposition in the near future,... Based on the theory of geo-economy,under the new situation of global economy,information network and China’s entry into WTO,also with the holding of APEC (in 2001) and the International Exposition in the near future,the Changjiang (Yangtze) River Delta is striding toward the spectacular international multi-polar situation and becomes one of core regions with high-speed development. Facing the ocean and world all along,leading the progressive tides of the age and scintillating the splendor of the nation,she does advance with time. Through a long period of irrigation projects construction and intensive operation of lands in previous agricultural society,the artificial wetland ecosystem with a positive cycle had ever been formed in this region. At present,environmental pollution and urban expansion resulted from post-industrialization are being rectified. The delta will be the paradigm of industrial and agricultural modernization along the sustainable development road. With the rapid development of urbanization,she has been one of the regions with the highest density population and high urbanization level. Taking the Changjiang River estuary and the Hangzhou Bay as two parts,she is continuously strengthening and adjusting her interior structure,expanding mothball space and constructing the oriental modern "logistics center" to link the whole world. The butterfly-style urban system of the Changjiang River Delta is flying,probably engendering earthshaking "butterfly effect". 展开更多
关键词 delta civilization artificial wetland ecosystem butterfly effect thechangjiang river celta
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Vegetation Change Prediction with Geo-Information Techniques in the Three Gorges Area of China 被引量:16
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作者 M. T. JABBAR SHI Zhi-Hua +1 位作者 WANG Tian-Wei CAI Chong-Fa 《Pedosphere》 SCIE CAS CSCD 2006年第4期457-467,共11页
A computerized parametric methodology was applied to monitor, map, and estimate vegetation change in combination with '3S' (RS-remote sensing, GIS-geographic information systems, and GPS-global positioning sys... A computerized parametric methodology was applied to monitor, map, and estimate vegetation change in combination with '3S' (RS-remote sensing, GIS-geographic information systems, and GPS-global positioning system) technology and change detection techniques at a 1:50000 mapping scale in the Letianxi Watershed of western Hubei Province, China. Satellite images (Landsat TM 1997 and Landsat ETM 2002) and thematic maps were used to provide comprehensive views of surface conditions such as vegetation cover and land use change. With ER Mapper and ERDAS software, the normalized difference vegetation index (NDVI) was computed and then classified into six vegetation density classes. ARC/INFO and ArcView software were used along with field observation data by GPS for analysis. Results obtained using spatial analysis methods showed that NDVI was a valuable first cut indicator for vegetation and land use systems. A regression analysis revealed that NDVI explained 94.5% of the variations for vegetation cover in the largest vegetation area, indicating that the relationship between vegetation and NDVI was not a simple linear process. Vegetation cover increased in four of areas. This meant 60.9% of land area had very slight to slight vegetation change, while 39.1% had moderate to severe vegetation change. Thus, the study area, in general, was exposed to a high risk of vegetation cover change. 展开更多
关键词 geo-information techniques vegetation change vegetation indices
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Ecology of macrozoobenthic communities in two plateau lakes of Southwest China 被引量:5
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作者 崔永德 王洪铸 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第4期345-352,共8页
Ecological studies on macrozoobenthos were conducted in two small plateau lakes in the Yunnan-Guizhou Plateau, Southwest China: Xingyun Lake (XL), a eutrophic lake whose main source of primary production was phytop... Ecological studies on macrozoobenthos were conducted in two small plateau lakes in the Yunnan-Guizhou Plateau, Southwest China: Xingyun Lake (XL), a eutrophic lake whose main source of primary production was phytoplankton (Chl α=99.76±24.01 μg/L), and Yangzong Lake (YL), a mesotrophic lake. Sampling was carried out from October 2002 to May 2004. Altogether 23 benthic taxa were identified in XL and 21 taxa in YL. The density of benthos in XL was much lower than that in YL, but the biomass was about equal in the two lakes, being I 423 ind/m^2 and 8.71 g/m^2 in XL and 4 249 ind/m^2 and 8.60 g/m^2 in YL. The dominant species were Limnodrilus hoffmeisteri, Branchiura sowerbyi, Aulodrilus pluriseta and Chironomus sp. in XL and Limnodrilus hoffrneisteri, Aulodrilus pluriseta and Bellamya sp. in YL. Seasonal fluctuation occurred, showing richer species in summer and winter, but the density and biomass varied in different ways in the two lakes. Analyses on functional feeding groups indicate that collector-gatherers were predominant, but the relative abundances of other groups were different. Stepwise multiple regression analysis demonstrated that the water depth, conductivity and chlorophyll a were the key factors affecting macrozoobenthic abundance in the lakes. 展开更多
关键词 plateau lakes macrozoobenthos taxonomic composition standing crop functional feeding group environmental analysis
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