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Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value 被引量:7
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作者 TIAN Wen-xin, LI Zuo-yong, LIU Wei, YU Chun-xue College of Resources and Environmental Sciences, Chengdu University of Information Technology, Chengdu 610225, China 《Meteorological and Environmental Research》 CAS 2011年第4期65-67,71,共4页
[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey cl... [Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment. 展开更多
关键词 NORMALIZATION Gray clustering method eco-environment quality evaluation Chaohu basin China
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A Study on the Path of Promoting External Dissemination of Regional Culture with Translation Technology under the Background of New Quality Productivity
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作者 Juan Zhou 《Journal of Contemporary Educational Research》 2024年第8期26-31,共6页
With the introduction of the concept of new quality productivity characterized by high technology,efficiency,and quality,various industries in China have ignited a high spirit of innovation and development.Against thi... With the introduction of the concept of new quality productivity characterized by high technology,efficiency,and quality,various industries in China have ignited a high spirit of innovation and development.Against this background,this article analyzes the significance and current situation of the external dissemination of regional culture and combines the application of translation technology empowered by new quality productivity to explore a path suitable for the wider,more effective,and higher-quality external dissemination of regional culture.The aim is to provide practical experience for promoting the effective dissemination of regional culture in China to the world and better build a cultural power. 展开更多
关键词 New quality productivity regional culture External dissemination Translation technology
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Spatial-temporal changes and driving factors of eco-environmental quality in the Three-North region of China 被引量:10
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作者 LONG Yi JIANG Fugen +2 位作者 DENG Muli WANG Tianhong SUN Hua 《Journal of Arid Land》 SCIE CSCD 2023年第3期231-252,共22页
Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-envir... Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-environmental quality is essential for environmental protection and ecological balance.The remote sensing ecological index(RSEI)can quickly and objectively quantify eco-environmental quality and has been extensively utilized in regional ecological environment assessment.In this paper,Moderate Resolution Imaging Spectroradiometer(MODIS)images during the growing period(July-September)from 2000 to 2020 were obtained from the Google Earth Engine(GEE)platform to calculate the RSEI in the three northern regions of China(the Three-North region).The Theil-Sen median trend method combined with the Mann-Kendall test was used to analyze the spatial-temporal variation trend of eco-environmental quality,and the Hurst exponent and the Theil-Sen median trend were superimposed to predict the future evolution trend of eco-environmental quality.In addition,ten variables from two categories of natural and anthropogenic factors were analyzed to determine the drivers of the spatial differentiation of eco-environmental quality by the geographical detector.The results showed that from 2000 to 2020,the RSEI in the Three-North region exhibited obvious regional characteristics:the RSEI values in Northwest China were generally between 0.2 and 0.4;the RSEI values in North China gradually increased from north to south,ranging from 0.2 to 0.8;and the RSEI values in Northeast China were mostly above 0.6.The average RSEI value in the Three-North region increased at an average growth rate of 0.0016/a,showing the spatial distribution characteristics of overall improvement and local degradation in eco-environmental quality,of which the areas with improved,basically stable and degraded eco-environmental quality accounted for 65.39%,26.82%and 7.79%of the total study area,respectively.The Hurst exponent of the RSEI ranged from 0.20 to 0.76 and the future trend of eco-environmental quality was generally consistent with the trend over the past 21 years.However,the areas exhibiting an improvement trend in eco-environmental quality mainly had weak persistence,and there was a possibility of degradation in eco-environmental quality without strengthening ecological protection.Average relative humidity,accumulated precipitation and land use type were the dominant factors driving the spatial distribution of eco-environmental quality in the Three-North region,and two-factor interaction also had a greater influence on eco-environmental quality than single factors.The explanatory power of meteorological factors on the spatial distribution of eco-environmental quality was stronger than that of topographic factors.The effect of anthropogenic factors(such as population density and land use type)on eco-environmental quality gradually increased over time.This study can serve as a reference to protect the ecological environment in arid and semi-arid regions. 展开更多
关键词 eco-environmental quality remote sensing ecological index Google Earth Engine Hurst exponent geographical detector Three-North region of China
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Changes and spatial patterns of eco-environment in the farming-pastoral region of northern China 被引量:2
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作者 JIANG Weiguo LI Jing +2 位作者 LI Jiahong CHEN Yunhao WU Yongfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期329-336,共8页
This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then di... This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then discusses in detail the methods about evaluating eco-environment background condition and analyzing eco-environment change. The eco-environment background conditions of 1989 and 1999 are synthetically appraised. Finally, the paper analyzes the spatial distribution, quantitative change, the trend of change, the areas of change and the dynamic spatial pattern of eco-environment. The results are as follows: (1) The eco-environment background condition becomes worse from southeast to northwest in the fanning-pastoral region of northern China. (2) The eco-environment background condition deteriorates from 1989 to 1999. (3) In the adjacent areas of Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia, Horqin Sandy Land and its peripheries, and eastern Qinghai orovince, eco-environmental deterioration is very serious. 展开更多
关键词 fanning-pastoral region eco-environment spatial pattern northern China
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Investigation of Groundwater Quality with Borehole Depth in the Basin Granitoids of the Ashanti Region of Ghana
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作者 Bernard Ofosu Augustine Kofi Asante +2 位作者 Festus Anane Mensah Umar-Farouk Usman Naa Korkoi Ayeh 《Journal of Water Resource and Protection》 CAS 2024年第5期381-394,共14页
The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study ther... The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study therefore seeks to investigate the relationship between borehole depth and groundwater quality across the granitoid aquifers within the Birimian Supergroup in the Ashanti Region. Physicochemical analysis records of groundwater quality data were collected from 23 boreholes of public and private institutions in the Ashanti Region of Ghana, and the parametric values of iron, fluoride, total hardness, pH, nitrate, and nitrite were used to study the groundwater quality-depth relationship. The results showed that the depth-to-groundwater quality indicated a marginal increase in water quality in the range of 30 to 50 m, which is mathematically represented by the low-value correlation coefficient (r<sup>2</sup> = 0.026). A relatively significant increase occurs in the depth range of 50 to 80 m, which is given by a correlation coefficient of r<sup>2</sup> = 0.298. The mean percent parameter compatibility was 74%, 82%, 89%, and 97% at 50, 60, 70, and 80 m depths, respectively. The variations in groundwater quality per depth ratio ranged from 1.48, 1.37, 1.27, and 1.21 for 50, 60, 70, and 80 m depth, respectively. The recommended minimum borehole depth for excellent groundwater quality is suggested with a compatibility per meter depth ratio of 1.37. This results in a range between 50 and 70 m as the most desirable drilling depth for excellent groundwater quality within the granitoids of the Birimian Supergroup of the Ashanti Region in Ghana. 展开更多
关键词 Groundwater quality Borehole Depth Birimian Supergroup Granitoid Aquifers Ashanti region
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Regional Air Quality of the Nigeria’s Niger Delta 被引量:2
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作者 Precious N. Ede David O. Edokpa 《Open Journal of Air Pollution》 2015年第1期7-15,共9页
There is no systematic attempt to evaluate the air quality of any settlement in the Niger Delta region over a long period. Records of air quality data for this study were generated through secondary sources from impac... There is no systematic attempt to evaluate the air quality of any settlement in the Niger Delta region over a long period. Records of air quality data for this study were generated through secondary sources from impact assessment of facilities aimed at implementing air quality regulations on the environment. Suspended particulate matter in the region’s atmosphere ranged from 40 mg/m3 in Brass to 98 mg/m3 in Port Harcourt. Carbon monoxide concentrations were highest in Mbiama (191 mg/m3). Nitrogen dioxide concentration was highest in Bonny (187 mg/m3), and sulphur dioxide concentrations ranged from 19 mg/m3 in Ukwugba to 90 mg/m3 in Port Harcourt. Total hydrocarbon ranged from 78 mg/m3 in Odukpani to 192 mg/m3 in Nchia. Carbon dioxide ranged from 400 ppm in Buguma to 450 ppm in Port Harcourt. The most abundant of the VOCs is benzene and toluene. Ethylene was detected only in one station at concentration of 0.1 mg/m3 which was negligible. The most abundant of the metals was zinc, which was present at above 2 mg/m3 in most of the study settlements. In remote settlements like Buguma and Emuoha, some of the metals were not detected at all. In some instances, short-term limits for the pollutants exceeded WHO standards. The need for stakeholders in the region to articulate initiatives that support quality environmental practices was emphasized as laws pertaining to air quality regulations which are weak and less enforceable. 展开更多
关键词 NIGER DELTA regional AIR quality EMISSIONS from PETROLEUM
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Regional Distribution of Cotton Fiber Quality in China 被引量:2
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作者 TANG Shu-rong,YANG Wei-hua(Cotton Research Institute,Chinese Academy of Agricultural Sciences Key Laboratory of Cotton Genetic Improvement,Ministry of Agriculture,Anyang,Henan 455000,China) 《棉花学报》 CSCD 北大核心 2008年第S1期125-,共1页
The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major ... The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major cotton production provinces between 2001 to 2005 were analyzed.Eight quality 展开更多
关键词 regional Distribution of Cotton Fiber quality in China
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REFORM AND TEACHING QUALITY—EXEMPLIFICATION OF REGIONAL PHYSICAL GEOGRAPHY
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作者 李春芬 《Chinese Geographical Science》 SCIE CSCD 1992年第3期83-89,共7页
There are a number of factors involved in teaching quality. Among them teaching materials or textbooks are of primary importance, the presentation of which relies first of all on the viewpoint to structure the content... There are a number of factors involved in teaching quality. Among them teaching materials or textbooks are of primary importance, the presentation of which relies first of all on the viewpoint to structure the contents geographically. Whatever branch of geography you are teaching or in pursuit, geographical viewpoint is vitally important. This paper in discussing innovation of geographical education about these institutions with the course of regional physical geography as an example. The higher education of our discipline is in pressing need of innovation and thereby upgrading quality. 展开更多
关键词 TEACHING REFORM TEACHING quality regional physical GEOGRAPHY
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Study on Rear-end Real-time Data Quality Control Method of Regional Automatic Weather Station
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作者 WANG Chao-qiu 《Meteorological and Environmental Research》 CAS 2011年第9期6-8,12,共4页
[Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional au... [Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional automatic weather station were introduced. Each element was treated with systematic quality control procedure. The existence of rear-end real time data of regional meteorological station in Guangxi was expounded. Combining with relevant elements and linear changes, improvement based on traditional quality control method was made. By dint of evaluation and relevant check of element, the quality of temperature and pressure was controlled. [Result] The method was optimized based on traditional quality control method, and it narrowed the effectiveness of real-time data quality control. The quality check of hourly precipitation applied relevant check of hourly minimum temperature, vertical consistency check of radar data, which can effectively improve the accuracy and credibility of hourly precipitation quality control. [Conclusion] The method was on trial for one year in the quality control of real-time data in the regional automatic meteorological station in Guangxi and had gained good outcome. 展开更多
关键词 regional automatic stations Real-time data quality control Method research China
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Regional difference and dynamic evolution of development quality of power industry in China
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作者 Sha Yu Yongjian Pu +2 位作者 Lefeng Shi Hao Yu Yixiang Huang 《Chinese Journal of Population,Resources and Environment》 2023年第1期1-12,共12页
To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the... To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the regional differences and evolutionary trends in the development quality of China’power sector has a high value to inspire the next improvement direction toward how to integrate regional power recourses to an overall optimization level.Motived by this purpose,this paper uses the entropy method to evaluate the com‐prehensive and subsystem indices of the development quality of the power industry,and reveals their re‐gional differences and evolutionary trends with the help of the Dagum Gini coefficient and Kernel density es‐timation methods.The findings show that:There are obvious regional differences in the development quality of China’s power industry,and the differences are steadily declining in all regions except the West.Regional differences are mainly derived from inter-regional differences,with the largest inter-regional differences in the East-Northeast region.Intra-regional differences show a distribution pattern of East>West>North‐east>Center. 展开更多
关键词 Development quality of power industry regional difference The Dagum Gini Dynamic evolution Kernel density
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Research on Dynamic Change of Regional Cultivated Land Quality and Its Influence Factors
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作者 Ziwei WANG Lingchao WANG +1 位作者 Yanhua SONG Yan TIAN 《Meteorological and Environmental Research》 CAS 2021年第5期77-83,共7页
According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quali... According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value. 展开更多
关键词 regional cultivated land quality Driving mechanism Mutation area Gradient area Zhengzhou City
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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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Thoughts on Establishment of the Agricultural Products Quality and Safety(Standards) Cooperation Center in Asia-Pacific Region
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作者 章力建 陈天金 李鹏 《China Standardization》 2012年第2期45-49,共5页
The establishment of agricultural products quality and safety cooperation mechanism and the research demonstration center in the Asia-Pacific reg coordinating each other, is not only of great ening cooperation with co... The establishment of agricultural products quality and safety cooperation mechanism and the research demonstration center in the Asia-Pacific reg coordinating each other, is not only of great ening cooperation with countries in Asia-Pacific region and for agricultural production safety of those countries in Asia- Pacific region, but also very necessary for our country to build a responsible image in the quality and safety of agricultural products, protection of the benefit of agriculture-related enterprises, increasing exports, ensuring imported food safety and China's national food security, as Well as nice exploration of establishing the global agricultural' products quality and safety cooperation center. 展开更多
关键词 the Asia-Pacific region the quality and safety &agricultural products STANDARDIZATION cooperation mechanisms
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Groundwater quality and land use change in a typical karst agricultural region:a case study of Xiaojiang watershed,Yunnan 被引量:15
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作者 JIANG Yongjun YUAN Daoxian +3 位作者 XIE Shiyou LI Linli ZHANG Gui HE Raosheng 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期405-414,共10页
Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004... Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004, supported by the GIS, we probe into the law and the reason of its space-time change of the groundwater quality over the past 22 years in the paper. The results show: (1) There were obvious temporal and spatial changes of groundwater quality during the past 22 years. (2) Concentrations of NH4^+, SO4^2- , NO3, NO2^-, Cl^- and the pH value, total hardness, total alkalinity increased significantly, in which NH4^2-, NO3, and NO2^- of groundwater exceeded the drinking water standards as a result of non-point pollution caused by the expansion of cultivated land and mass use of the fertilizer and pesticide. (3) Oppositely, Ca^2+ and HCO3^- showed an obvious decline trend due to forest reduction and degradation and stony desertification. Meantime, there was a dynamic relation between the groundwater quality change and the land use change. 展开更多
关键词 groundwater quality space-time change land use change typical karst agricultural region GIS Xiaojiang watershed
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A New Version of Regional Ocean Reanalysis for Coastal Waters of China and Adjacent Seas 被引量:10
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作者 韩桂军 李威 +6 位作者 张学峰 王喜冬 吴新荣 付红丽 张晓爽 张连新 李冬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第4期974-982,共9页
A new regional ocean reanalysis over multiple decades (1958 2008) for the coastal waters of China and adjacent seas has been completed by the National Marine Data and Information Service (NMD[S) under the CORA (C... A new regional ocean reanalysis over multiple decades (1958 2008) for the coastal waters of China and adjacent seas has been completed by the National Marine Data and Information Service (NMD[S) under the CORA (China Ocean ReAnalysis) project. Evaluations were performed on three aspects: (1) the improvement of general reanalysis quality; (2) eddy structures; and (3) decadal variability of sea surface height anomalies (SSHAs). Results showed that the quality of the new reanalysis has been enhanced beyond ~40% (39% for temperature, 44% for salinity) in terms of the reduction of root mean squared errors (RMSEs) for which the reanalysis values were compared to observed values in the observational space. Compared to the trial version released to public in 2009, the new reanalysis is able to reproduce more detailed eddy structures as seen in satellite and in situ observations. EOF analysis of the reanalysis SSHAs showed that the new reanalysis reconstructs the leading modes of SSHAs much better than the old version. These evaluations suggest that the new CORA regional reanalysis represents a much more useful dataset for the community of the coastal waters of China and adjacent seas. 展开更多
关键词 regional ocean reanalysis China ocean reanalysis (CORA) improved quality of reanalysis
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Resource and Environmental Quality Changes and Adjustment Principles for Sustainable Development in Rapidly Developing Coastal Region of Southeastern China 被引量:10
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作者 ZHAO QIGUO Institute of Soil Science, the Chinese Academy of Sciences, P. O. Box 821, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 2001年第4期289-299,共11页
Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns... Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns in China, and the large export-oriented economy makes itself a strategic importance while China enters into international markets. The problems facing to this region include arable land reduction, land degradation aggravation, high percentage of built-up land with high rate of expansion, expanded non-point pollution, deteriorated water quality, decreasing biodiversity, destroyed ecosystems, severe air pollution, frequently occurred acid rain, and multi-pollutants. The important research fields in the near future should include a) influence of high-intensity exploitation of resources on changes of environment quality and its feedback; b) interface processes, key mechanisms and adjustment principles for degradation of water-, land-, and air-resources and environmental quality; c) evolvement processes and nurturing theory of biodiversity and ecological resources; and d) spatio-temporal variation and human-induced effects on regional resources and environment quality. Strategies for sustainable development in the region are as follows: a) controlling to ensure basic cultivated land area; b) enforcing remediation of polluted water environment, and controlling non-point pollution; c) strengthening ecological construction and ecological security; and d) controlling multi-pollution and preventing trace toxic pollutants. 展开更多
关键词 coastal region environment quality fast economic development southeastern China water- land resource
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Development Geography for exploring solutions to promote regional development 被引量:3
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作者 Xiangzheng Deng Yifei Wang Malin Song 《Geography and Sustainability》 CSCD 2023年第1期49-57,共9页
Development Geography is a branch of geography which studies the socioeconomic development of different countries and regions worldwide.Its related research provides informative ideas for promoting regionally co-ordin... Development Geography is a branch of geography which studies the socioeconomic development of different countries and regions worldwide.Its related research provides informative ideas for promoting regionally co-ordinated development.This study introduces the basic connotation and theory of Development Geography re-search,and clarifies its primary indicators and core approaches to provide solutions for regional development.Finally,the application in regional development research under globalization is proposed.It is considered that the systematically integrated geography paradigm highlights the advantages of Development Geography in re-gional development research.As a result of its“differentiation characteristics-diffusion state-convergence mode”,an important theoretical basis and methodological paradigm are provided to explore the features of regional de-velopment.Since the development gaps among regions exist long throughout the world,Development Geography research ought to focus on new characteristics and challenges of regional development,to provide a theoretical basis for synergy management of sustainable development goals and international cooperation.This contributes to high-quality regional development. 展开更多
关键词 Development Geography regional development Geophysical factors quality of life Sustainable development
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Regional Merge K-means图像分割算法及其质量评价 被引量:2
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作者 余寒 刘汉湖 +1 位作者 曾敏 陈军 《河南科学》 2020年第3期370-375,共6页
K值是基于K-means聚类算法进行图像分割效果的关键因素,为了解决K值过小,图像分割不明显,K值过大,图像分割信息过于碎片化的问题,提出一种Regional Merge K-means(RMK)算法.首先对图像运用K-means算法进行聚类,然后运用区域合并(Regiona... K值是基于K-means聚类算法进行图像分割效果的关键因素,为了解决K值过小,图像分割不明显,K值过大,图像分割信息过于碎片化的问题,提出一种Regional Merge K-means(RMK)算法.首先对图像运用K-means算法进行聚类,然后运用区域合并(Regional Merge)优化图像分割效果,最后利用不同图像进行图像分割试验,并选用不同的质量评价指标对试验结果进行评价.结果表明,该算法能显著优化图像分割效果. 展开更多
关键词 图像分割 聚类算法 regional MERGE K-means(RMK) 质量评价
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Evaluation and Driving Force Analysis of Cultivated Land Quality in Black Soil Region of Northeast China 被引量:1
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作者 WANG Mingchang LIU Xingnan +4 位作者 LIU Ziwei WANG Fengyan LI Xiaoyan HOU Guanglei ZHAO Shijun 《Chinese Geographical Science》 SCIE CSCD 2023年第4期601-615,共15页
Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this st... Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this study,320 counties in the black soil region of Northeast China(BSRNC)represent the research units used to construct the CQE system measuring the soil properties(SP),cultivated land productivity(CLP),ecological environment(EE)and social economy(SE).The total of 19 factors were selected to calculate the integrated fertility index(IFI)and divided into grades.Simultaneously,we used the coupling coordination degree model to comprehensively analyze the spatial pattern of the cultivated land quality(CLQ)in the BSRNC,and use the structural equation model(SEM)to analyze the driving mechanism.The results show the following:1)The CLQ of 262 counties in the BSRNC is in a state of coupling and coordination,and the coupling and coordination degree presents a spatial distribution pattern of‘high in the southwest and northeast,low in the northwest and southeast’.The coordinated development degree of 271 counties is between 0.4 and 0.6,which is in a transitional state between coordination and disorder.2)The CLQ in the BSRNC is generally good,with an average grade of 3.High-quality cultivated land accounts for 58.45%of all counties,middle-and upper-quality cultivated land accounts for 27.05%,and poor-quality cultivated land accounts for 14.49%.3)The SEM analysis shows that the SP,CLP,EE,and SE all influence the CLQ.Among them,the SP has the largest driving force on the CLQ,while the SE has the smallest driving force on it.The results confirm that the main factors affecting the evaluation results are crop productivity level,normalized difference vegetation index,ratio vegetation index,difference vegetation index,and organic carbon content.When implementing protection measures in counties with a low CLQ,considering a balanced coordination of multiple systems and reasonably controlling the quality degradation are important.This study provides the current situation and driving factors of the CLQ in the BSRNC and will play an important role in black soil governance and utilization. 展开更多
关键词 cultivated land quality evaluation(CQE) black soil region of Northeast China(BSRNC) coupling coordination degree model structural equation model(SEM) driving forces
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THE DISCUSSION ON THE MEASURES OF INCREASING NURSERY STOCK QUALITY IN FRIGID REGION OF CHINA
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作者 Qi Mingcong Shen Hailong Northeast Forestry University Yang Xiujuan Museum of Heilongjiang Province 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1993年第2期43-50,共8页
Through several years seedling-growing experiments in nursery in Daxing‘anMountains forest region,the author posed that the seedling cultivated for the region mustpossess the characteristics of being suited to thin a... Through several years seedling-growing experiments in nursery in Daxing‘anMountains forest region,the author posed that the seedling cultivated for the region mustpossess the characteristics of being suited to thin and meager soil and having strongresistance to adverse conditions.For this purpose,the cultivation regime ought to bedirectization,standardization and programmatization;seedling growth ought to be promotedby regulating ecological conditions;and the mursery stock quality ought to be tested usingvigor index. 展开更多
关键词 Seedling-growing measure Frigid region NURSERY STOCK quality
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