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Spatiotemporal variation of ecological environment quality and extreme climate drivers on the Qinghai-Tibetan Plateau
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作者 SUN Tao YANG Yan-mei +5 位作者 WANG Ze-gen YONG Zhi-wei XIONG Jun-nan MA Guo-li LI Jie LIU Ao 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2282-2297,共16页
Protecting the ecological security of the Qinghai-Tibet Plateau(QTP)is of great importance for global ecology and climate.Over the past few decades,climate extremes have posed a significant challenge to the ecological... Protecting the ecological security of the Qinghai-Tibet Plateau(QTP)is of great importance for global ecology and climate.Over the past few decades,climate extremes have posed a significant challenge to the ecological environment of the QTP.However,there are few studies that explored the effects of climate extremes on ecological environment quality of the QTP,and few researchers have made quantitative analysis.Hereby,this paper proposed the Ecological Environmental Quality Index(EEQI)for analyzing the spatial and temporal variation of ecological environment quality on the QTP from 2000 to 2020,and explored the effects of climate extremes on EEQI based on Geographically and Temporally Weighted Regression(GTWR)model.The results showed that the ecological environment quality in QTP was poor in the west,but good in the east.Between 2000 and 2020,the area of EEQI variation was large(34.61%of the total area),but the intensity of EEQI variation was relatively low and occurred mainly by a slightly increasing level(EEQI change range of 0.05-0.1).The overall ecological environment quality of the QTP exhibited spatial and temporal fluctuations,which may be attributed to climate extremes.Significant spatial heterogeneity was observed in the effects of the climate extremes on ecological environment quality.Specifically,the effects of daily temperature range(DTR),number of frost days(FD0),maximum 5-day precipitation(RX5day),and moderate precipitation days(R10)on ecological environment quality were positive in most regions.Furthermore,there were significant temporal differences in the effects of consecutive dry days(CDD),consecutive wet days(CWD),R10,and FD0 on ecological environment quality.These differences may be attributed to variances in ecological environment quality,climate extremes,and vegetation types across different regions.In conclusion,the impact of climate extremes on ecological environment quality exhibits complex patterns.These findings will assist managers in identifying changes in the ecological environment quality of the QTP and addressing the effects of climate extremes. 展开更多
关键词 Ecological environment quality Extreme climate Geographically and Temporally Weighted Regression Qinghai-Tibetan Plateau
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Groundwater and environmental challenges in Asia
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作者 Yan-pei Cheng Fa-wang Zhang +1 位作者 Hua Dong Xue-ru Wen 《Journal of Groundwater Science and Engineering》 2024年第2期223-236,共14页
Asia stands out as the most populous and geographically diverse region globally.The pressing issues of water resource development and the resulting ecological impacts are exacerbated by the region's rapid populati... Asia stands out as the most populous and geographically diverse region globally.The pressing issues of water resource development and the resulting ecological impacts are exacerbated by the region's rapid population growth and economic expansion.Groundwater,a vital source of water in Asia,faces significant disparities in distribution and suffers from unsustainable exploitation practices.This study applies groundwater system theory and categorizes Asia into 11 primary groundwater systems and 36 secondary ones,based on intercontinental geological structures,climate,terrain,and hydrogeological characteristics.As of the end of 2010,Asia's assessed groundwater resources totalled 4.677×10^(9) m^(3)/a,with exploitable resources amounting to 3.274×10^(9) m^(3)/a.By considering the geological environmental impacts of groundwater development and the distinctive characteristics of terrain and landforms,six categories of effect zones with varying distribution patterns are identified.The current research on Asia's groundwater resources,environmental dynamics,and human impacts aims to provide a theoretical foundation for sustainable groundwater management and environmental conservation in the region. 展开更多
关键词 ASIA Groundwater resources Groundwater quality Ecological environment environmental impacts
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Study of poverty alleviation strategy based on labor force quality improvement and ecological protection in Western China 被引量:1
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作者 Hui Liu Wuzhati Yeerken Hansen Stein 《Chinese Journal of Population,Resources and Environment》 2013年第3期218-226,共9页
Fragile ecological environment and poverty correlate to and reinforce each other closely in Western China.At the same time,Western China is also the most prominent area of the knowledge and human poverty with very low... Fragile ecological environment and poverty correlate to and reinforce each other closely in Western China.At the same time,Western China is also the most prominent area of the knowledge and human poverty with very low labor force quality.On the basis of analyzing the characteristics of poverty in Western China,this paper studies the coupling relationship between fragile ecological environment and poverty in Western China,including the impacts of fragile environment on poverty occurrence and the effects of ecological construction on poverty alleviation.It also analyzed how low labor quality causes persistent poverty in the western region.At the end of the paper,strategies of diversity poverty alleviation in Western China are suggested based on sustainable development,including education improvement,ecological construction,industries development,infrastructure construction,planning institution innovation,and so on. 展开更多
关键词 POVERTY alleviation LABOR FORCE quality ECOLOGICAL environment WESTERN China
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Assessment of Effects of Qinshan Nuclear Power Station on the Ecological Environment and Water Quality of its Adjacent Waters after its Running
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作者 Yang Guanming, He Dehua, Wang Zhengfang, Wang Chunsheng, Chen Yongshou, Hu Xigang (Second Institute of Oceanography, SOA) 《Marine Science Bulletin》 CAS 1999年第2期1-8,共8页
On the basis of the data of biological and nonbiological factors collected respectively from 1989 to 1990 and from 1995 to 1996 in the waters nearby the Qinshan Nuclear Power Station, the ecological environment and wa... On the basis of the data of biological and nonbiological factors collected respectively from 1989 to 1990 and from 1995 to 1996 in the waters nearby the Qinshan Nuclear Power Station, the ecological environment and water quality of the waters are analyzed and assessed in the paper. The results show: (a) the surveyed area has the typical ecological characteristics of high tidal range estuary, rich nutrients and low biological productivity, (b) tide, runoff and offshore seawater intrusion are the key factors which result in seasonal and annual changes of various biological and non-biological factors, (c) the risking of seawater eutrophication index is resulted from enormous amount of the discharges of industrial and domestic sewage, (d) because the survey area is located in a high tidal-range estuary, thermal effluent from cooling system does not induce significant temperature changes, ( e) the first stage project of Qinshan nuclear power station has no notable impacts on the ecological environment in 展开更多
关键词 nuclear power STATION WATERS ECOLOGICAL environment water quality ASSESSMENT
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Eco-environmental Quality Evaluation of Coal City Based on AHP-PCA Model 被引量:17
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作者 李峰 刘小阳 +1 位作者 于雪涛 刘文龙 《矿业安全与环保》 北大核心 2017年第5期103-106,110,共5页
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Evaluation of Ecological Environment Quality of Typical Forest Parks 被引量:1
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作者 Dongmei ZHANG Shuzhen PENG +2 位作者 Weijun ZHAO Mengyuan GAO Junqing HAN 《Agricultural Biotechnology》 CAS 2019年第5期112-116,共5页
Forest tourist areas have an excellent ecological environment,which is conducive to people's physical and mental health.In this study,Fuzhou National Forest Park and Wuying National Forest Park were selected as ty... Forest tourist areas have an excellent ecological environment,which is conducive to people's physical and mental health.In this study,Fuzhou National Forest Park and Wuying National Forest Park were selected as typical representatives of the southern and northern forest parks,respectively,which were compared by qualitative and quantitative research methods from such five aspects as air quality,climate quality,water environment quality,acoustic environment quality and biological population in some forest areas.The results showed that Fuzhou National Forest Park has a concentration of negative oxygen ions much higher than Wuying National Forest Park,and is thus more conducive to people's health;and it has the characteristics of warm and comfortable climate throughout the year and high biodiversity,but the noise is 4.35 db higher than Wuying National Forest Park,and the water quality is slightly poorer than that of Wuying National Forest Park.And its DO value is about 3.89 smaller in autumn than in summer.In Wuying National Forest Park,the concentration of negative oxygen ions is 53.6% lower than Fuzhou National Forest Park,but it is also above the national standard.The climate is only comfortable in June-August,and is colder or cooler in other months.The water quality is better than that of Fuzhou National Forest Park.In particular,the PH value is about 0.38 lower than that of Fuzhou National Forest Park.It has its own unique biological characteristics.The number of tourists in summer is higher,resulting in higher noise in summer than in autumn.The two forest parks in the north and the south are both good places for people to relax and enjoy. 展开更多
关键词 FOREST TOURISM environmental quality quality EVALUATION ECOLOGICAL environment
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基于Landsat的巴音河流域生态环境综合演化分析
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作者 吴冰洁 文广超 +3 位作者 赵梅娟 谢洪波 冯雅杰 贾琳 《自然资源遥感》 CSCD 北大核心 2024年第1期227-234,共8页
为揭示巴音河流域生态环境的综合演化特征,指导当地或类似地区土地利用和生态环境优化管理,选取2005—2020年12景遥感影像数据,基于研究区生态环境问题,引入地理探测器定量探究关键因子,结合生态系统服务和权衡的综合评估模型(integrate... 为揭示巴音河流域生态环境的综合演化特征,指导当地或类似地区土地利用和生态环境优化管理,选取2005—2020年12景遥感影像数据,基于研究区生态环境问题,引入地理探测器定量探究关键因子,结合生态系统服务和权衡的综合评估模型(integrated valuation of ecosystem services and trade-offs,InVEST),综合运用统计分析、叠加分析、层次分析等方法建立生态环境质量评价模型,揭示流域生态环境的综合演化特征。结果表明:影响流域生态环境质量演化的关键因子为人口数量、国内生产总值、高程和降雨量,流域生态环境质量综合评价值从0.455增至0.533,整体呈上升趋势。研究区内生态环境质量地域差异明显,14.9%的区域呈现退化状态,主要分布于巴音河流域附近及德令哈市区周边区域;33.6%的区域呈改善状态,分布于巴音河流域中下游湖泊以南区域。研究表明巴音河流域在未来生态环境保护与规划中应更注意城镇化过程中农业及其他生态用地与建设用地的平衡,科学地进行空间格局规划,实现经济与生态的协调发展。 展开更多
关键词 巴音河流域 地理探测器 InVEST模型 生态环境质量 时空演化
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Integrated Assessment of Mineral Resources and Environmentin Mid-South of Shandong Province
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作者 Wei Min Yao Yonghui Wang Xueping Faculty of Earth Resources, China University Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期76-78,共3页
On the bases of the field survey and a large number of testing data, we process the qualitative and quantitative assessment of the mine environment in the mid south of Shandong Province using the following grade Ⅰ fa... On the bases of the field survey and a large number of testing data, we process the qualitative and quantitative assessment of the mine environment in the mid south of Shandong Province using the following grade Ⅰ factors:the surface subsidence in mining area, the three wastes of mine industries, the pollution sources, the surface water pollution, the underground water pollution and the air pollution. By means of emitting factor judgment and water quality indexes, we locate pollution sources, main pollutants, pollution type and pollution grade in the study area. Using the MAPGIS, we draw a zonality map of the mine environment. This paper attempts to offer a concrete example, including valuable assessment method, data and conclusion, for the assessment of mine environment from the integrated assessment of mineral resources and mine environment. This research is oriented towards the sustainable development and the ecological environment optimization. 展开更多
关键词 integrated assessment of resources and environment the quality assessment of environment water quality index emitting factor judgment liquid waste capacity per 10 000 yuan production value ecological environment optimization.
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Performance of a Horizontal Flow Constructed Reed Bed Filter for Municipal Wastewater Treatment: The Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal
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作者 Abdou Khafor Ndiaye Falilou Coundoul +2 位作者 Abdoulaye Deme Antonina Torrens Armengol Abdoulaye Senghor 《Natural Resources》 2024年第1期1-16,共16页
In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed... In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability. 展开更多
关键词 Constructed Wetlands Horizontal Flow Reed Beds Wastewater Treatment Phragmites and Typha Plants Physicochemical Pollutant Removal Microbiological Indicators Fecal Coliforms and Helminth Eggs Water quality improvement Senegal Water Reuse Standards Sustainable Water Management Agricultural Irrigation Reuse Nutrient Removal Efficiency environmental Engineering Ecological Sanitation Systems
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Discussion on Action and Potential of Fenlong Megascience in the Symbiosis between Human and Nature 被引量:3
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作者 韦本辉 申章佑 +6 位作者 周佳 周灵芝 李艳英 劳承英 甘秀芹 胡泊 韦元波 《Agricultural Science & Technology》 CAS 2017年第12期2303-2308,2311,共7页
The fourth new farming model Fenlong is identified as megascience for the first time. Fenlong can be directly applied to farming of farmland, remoulding of mortar black soil and saline alkali land and development of d... The fourth new farming model Fenlong is identified as megascience for the first time. Fenlong can be directly applied to farming of farmland, remoulding of mortar black soil and saline alkali land and development of degraded grassland. Deep loosening can create huge soil reservoirs, reduce fertilization, promote indi- rectly the improvement of river water fisheries and water sources and the upgrading of shaping and hydropower industry, thus making a new round of mobilization and pooling of natural resources. As a result, the nature is able to produce good food needed by human, the spatial dimension of the land is increased, the natural pre- cipitation storage is increased, the flood and drought disasters are reduced, the eco-environment is improved, and the economic benefits are increased. Fenlong is not restricted to global application by ecological region and crop variety and is not subject to the time-space constraints for a hundred thousand years. On the basis of utilizing the heaven and earth resources, it brings about a huge effect of mega- science. Compare with traditional farming, the depth under the mode of Fenlong is increased by 2-3 times, the contents of nutrient, water, oxygen and microorganism in the soil are increased by 10%-200%, the content of pale salt is increased by 20%-40%, the temperature is increased by 2-4 ~C, and the photosynthetic efficiency of crops is improved by 10%. Under the cultivation mode of Fenlong, the yield of crop applied with no fertilizers is increased by more than 10%, crop yield is still in- creased by more than 5% when the application amount of chemical fertilizer is re- duced by 10%-20%. Under the farming mode of Fenlong combined with no in- crease in fertilization, the crop yield, crop quality, farming efficiency, natural precipi- tation storage and air humidity are increased by 10%-50%, 5%, 15%, 100% and 5%, respectively, and the emissions of methane and other gases are reduced by more than 5%. Even in mortar black soil, saline alkali land and degraded grassland, the yield is still increased by 15%-50%. These improvement effects can last for many years, helping achieve the real harmonious coexistence between human and nature. 展开更多
关键词 Fenlong Megascience Autogeneration Yield and quality improvement Water conservation ecology Harmonious coexistence between human and nature
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Source analysis and risk evaluation of heavy metal in the river sediment of polymetallic mining area:Taking the Tonglüshan skarn type Cu-Fe-Au deposit as an example,Hubei section of the Yangtze River Basin,China 被引量:1
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作者 Jing Wang Xin-xin Zhang +5 位作者 Ai-fang Chen Bo Wang Qi-bin Zhao Guan-nan Liu Xiao Xiao Jin-nan Cao 《China Geology》 CAS 2022年第4期649-661,共13页
In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological... In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological risks of heavy metals in sediments.A geo-accumulation index method was used to evaluate the degree of heavy metal pollution in the sediment.The mean sediment quality guideline quotient was used for evaluating the ecological risk level of heavy metal in the sediment.And a method of correlation analysis,clustering analysis,and principal component analysis was used for preliminary analysis on the source of heavy metal in the sediment.It was indicated that there was extremely heavy metal pollution in the sediment,among which Cd was extremely polluted,Cu strongly contaminated,Zn,As,and Hg moderately contaminated,and Pb,Cr,and Ni were slightly contaminated.It was also indicated by the mean sediment quality guideline-quotient result that there was a high ecological risk of heavy metals in the sediment,and 64%of the sample sites had extremely high hidden biotoxic effects.For distribution,the contamination of branches was worse than that of the main channel of Daye Dagang,and the deposition of each heavy metal was mainly influenced by the distance from this sample site to the sewage draining exit of a tailings pond.The source analysis showed that the heavy metals in the sediment come from pollution discharging of mining and beneficiation companies,tailings ponds,smelting companies,and transport vehicles.In the study area,due to the influence of heavy metal discharging from these sources,the ecotoxicity of heavy metals in the sediment was extremely high,and Cd was the most toxic pollutant.The research figured out the key restoration area and elements for ecological restoration in the sediment of the Tonglüshan mining area,which could be referenced by monitoring and governance of heavy metal pollution in the sediment of the polymetallic mining area. 展开更多
关键词 Sediment Heavy metal pollution Ecological risks Geo-accumulation index method Sediment quality guideline-quotient Cluster analysis Principal component analysis Skarn-type Ecological environment survey Tonglüshan Daye Lake China
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Land reclamation pattern of iron mine in Tangshan
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作者 LI Fu-ping~(1,2), LIU Ren-yi~(2), ZHANG Jin-rui~(1,2), GUO Qiao-zhen~(2), WANG Hong-xin~(2) (1. University of Science and Technology Beijing, Beijing 100083, China 2. Hebei Institute of Technology, Tangshan 063009, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期159-163,共5页
Based on the analyses of the character of the exploitation of the iron ore resource and its destruction of eco-environment in Tangshan area, this paper puts forward the patterns of land reclamation which fits for this... Based on the analyses of the character of the exploitation of the iron ore resource and its destruction of eco-environment in Tangshan area, this paper puts forward the patterns of land reclamation which fits for this area. The patterns include the reclamation of ecological agriculture, planting directly on the tailing bin without covering soil, reclamation of mine tailings in the pool, and improvement of the soil quality by using tailings etc. Now, over 700hm^2 land has been reclaimed by taking advantage of the pattern in Tangshan and eight typical reclamation districts have been built. The rates of reclamation exceed 80% and have reached the advanced level of the world. Practice has proved that the eco-environment of the ore area has been greatly improved and the remarkable economic and social benefits have been gained. 展开更多
关键词 Land RECLAMATION IRON MINE RECLAMATION of ECOLOGICAL AGRICULTURE improvement of soil quality
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Analysis of Genetic Similarity for Improved Japonica Rice Varieties from Different Provinces and Cities in China
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作者 SHU Ai-ping ZHANG Yuan-yuan +3 位作者 CAO Gui-lan LU Qin ZHANG San-yuan HAN Long-zhi 《Agricultural Sciences in China》 CSCD 2010年第8期1093-1100,共8页
To provide a genetic basis for japonica rice breeding, the genetic similarity and cluster of 139 accessions of improved japonica rice varieties from 12 provinces and cities of China were analyzed using 34 SSR markers.... To provide a genetic basis for japonica rice breeding, the genetic similarity and cluster of 139 accessions of improved japonica rice varieties from 12 provinces and cities of China were analyzed using 34 SSR markers. Totally 198 alleles were detected among these improved japonica rice varieties with the average number of alleles per pair of primers was 5.3235. RM320, RM531, RM1, RM286, and RM336 showed more alleles, which were 15, 12, 11, 9, and 9, respectively. RM320, RM336, RM286 and RM531 showed higher genetic diversity indexes; which were 2.3324, 2.0292, 1.8996, and 1.7820, respectively. The range of genetic similar index among improved japonica rice varieties from different provinces was from 0.321 to 0.914, with the average of 0.686. There was a high genetic similarity among improved japonica rice varieties from Heilongjiang, Jilin, Liaoning, Ningxia, and Yunnan, which were located in similar latitude or similar ecological environment, while there was a low genetic similarity between improved japonica rice varieties from Guizhou and Jiangsu, and other provinces which were located in more different latitudes and ecological environments. The markers of RM320, RM531, RM1, RM286, and RM336 fit to be used in analysis of genetic diversity for improved japonica rice variety. The genetic similarity among improved japonica rice varieties from different provinces was closely associated with genetic basis of parents, and was also correlated with latitude and ecological environment where the varieties were bred. 展开更多
关键词 improved japonica rice variety genetic similarity genetic basis of parent ecological and climatic environment SSR marker
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Factors Influencing Patient-Centered Care in the Primary Health Care Settings: The Impact of the Pandemic Crisis and Nurses’ Experience
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作者 Adepeju Lateef Euphemia Mbali Mhlongo 《Open Journal of Nursing》 2022年第3期220-233,共14页
Patient-centered care has over the past decades, been recognized worldwide as an important component of the health system giving a wider dimension to high-quality healthcare and service delivery. The impact on healthc... Patient-centered care has over the past decades, been recognized worldwide as an important component of the health system giving a wider dimension to high-quality healthcare and service delivery. The impact on healthcare and services to the patient is the nurses’ ability to create a friendly rapport with the patients. Yet, the majority in the rural Primary Health Care facilities are still facing many challenges in demonstrating patient-centeredness services to the community. Thus, the objective of this study is to explore and describe the factors influencing patient-centered care provision and nurses’ experience in Primary Health Care facilities. An exploratory qualitative approach with purposive sampling was used to gather data. Individual interviews with 35 nurses were conducted using a semi-structure interview guide question in the Primary Health Care settings in Nigeria. Each of the interviews with the nurses lasted for 25 minutes to one hour. All interviews were audio-taped, and transcribed verbatim using Microsoft Word. The transcripts were read and re-read, coded using NVivo version 12 software to organize the relevant information and categorized them into themes and sub-themes. Thematic analysis guided this study. The findings revealed three themes and sub-themes. The impact of environmental factors with two subthemes—suitable working environment and coordinated care;resources—shortage of staff and inadequate resources as sub-themes, and lastly, cultural sensitivity and religious influence—communication. Poor implementation of PCC strategies in most of the PHC facilities could lead to poor patient care and a lack of job satisfaction among nurses. This study identified that nurses have both negative and positive experience in providing patient-centered care health services. Providing patient-centered care in the Primary Health Care setting promotes the goal of achieving universal health coverage in Nigeria if the government would prioritize nurses’ pay, employ more staff, provide a conducive working environment, and opportunities for further training programs for nurses to enable and empower them with the necessary knowledge and skills. This, in turn, will translate into a range of outcomes that are socially valued, such as health responsiveness, health coverage and fairness. 展开更多
关键词 Healthcare Service NURSING quality Care improvement Work environment Patient-Centered Care and Primary Health Care
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Education and Ecological Innovation Empowered by Technology:Innovation Practices in Inner Mongolia Universities
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作者 Yan-Dong Yu Noraini Binti Hj.Zainal Abidin 《Journal of Contemporary Educational Research》 2023年第12期119-124,共6页
This study aims to conduct a thorough analysis of the core elements of educational innovation in Inner Mongolian universities and their mechanisms for enhancing educational quality.By examining technological applicati... This study aims to conduct a thorough analysis of the core elements of educational innovation in Inner Mongolian universities and their mechanisms for enhancing educational quality.By examining technological applications,innovative teaching models,and the educational ecosystem,this paper explores the ways in which technological empowerment enhances students’learning experiences,the impact of innovative teaching models on educational quality,and the practical outcomes of ecological innovation theory in education.Additionally,relevant recommendations are provided for the future development trends of educational innovation in Inner Mongolian universities. 展开更多
关键词 Technological empowerment Education and ecological innovation Education quality improvement
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税收营商环境优化与企业全要素生产率——来自税务系统“放管服”改革的经验证据 被引量:3
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作者 储德银 程扬帆 《南开经济研究》 北大核心 2024年第4期45-65,共21页
优化税收营商环境不仅是提高企业生产效率和推动企业转型升级的重要战略举措,而且对实现经济高质量发展具有十分重要的现实意义。本文基于2013—2020年A股上市公司数据,并借助税务系统“放管服”改革试点这一准自然实验,构建多期双重差... 优化税收营商环境不仅是提高企业生产效率和推动企业转型升级的重要战略举措,而且对实现经济高质量发展具有十分重要的现实意义。本文基于2013—2020年A股上市公司数据,并借助税务系统“放管服”改革试点这一准自然实验,构建多期双重差分模型,实证考察了税收营商环境优化对企业全要素生产率的影响。研究表明,税务系统“放管服”改革对企业全要素生产率具有显著的正向影响,且该结论经过一系列稳健性检验依然成立。机制检验结果显示,税收营商环境优化主要是通过降低交易成本水平、提升资源配置效率以及鼓励技术创新来提高企业全要素生产率。异质性分析表明,对于中西部地区企业、非国有企业、环境不确定性高企业和成熟期企业,税收营商环境优化对企业全要素生产率的促进作用相对更加突出。随后的进一步分析表明,税收营商环境优化在提升企业全要素生产率的同时显著促进了企业经营规模扩大和产业链扩张。本文以上研究结论不仅能使我们更好地认识税收营商环境优化的经济效应,更是为培育有利于激发市场主体活力及推动企业提质增效的税收营商环境提供了经验证据与有益启示。 展开更多
关键词 “放管服”改革 税收营商环境 企业全要素生产率 企业提质增效
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中国生态环境质量现状及2016—2023年动态变化分析
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作者 马广文 张凤英 +6 位作者 牛丽楠 董贵华 高逸飞 解鑫 孟晓艳 何立环 林兰钰 《中国环境监测》 CAS CSCD 北大核心 2024年第3期1-11,共11页
以国家生态环境监测网数据为基础,分析2023年中国生态环境质量状况及2016年以来的变化特征。结果表明:2023年中国生态环境质量保持优良水平,其中,环境空气优良天数比例为85.5%,优良水质断面比例为89.4%,功能区声环境昼间和夜间达标率分... 以国家生态环境监测网数据为基础,分析2023年中国生态环境质量状况及2016年以来的变化特征。结果表明:2023年中国生态环境质量保持优良水平,其中,环境空气优良天数比例为85.5%,优良水质断面比例为89.4%,功能区声环境昼间和夜间达标率分别为96.1%和87.0%,生态质量指数为59.6;2016—2023年生态环境质量持续改善,其中,环境空气优良天数比例上升2.4个百分点,优良水质断面比例上升21.6个百分点,功能区声环境昼间和夜间达标率分别上升3.9个、13.0个百分点。但各生态环境要素质量在部分区域、特定时段不容乐观,京津冀及周边地区、汾渭平原空气质量总体水平仍低于全国平均水平,颗粒物和臭氧浓度偏高;个别流域仍为轻度污染,优良水质断面比例远低于全国水平,某些流域仍存在劣Ⅴ类水质断面,化学需氧量、总磷和高锰酸盐指数是地表水中的主要超标指标;声环境1类和4a类功能区夜间达标率仍相对较低;新疆中北部和甘肃西部地区仍有部分县域生态质量为四类或五类,生态脆弱的情况尚未得到根本改善。随着生态环境污染治理进入攻坚期,控制污染增量的边际成本增加,生态环境质量进一步改善的难度越来越大。 展开更多
关键词 生态环境质量 环境空气 地表水 声环境 生态质量 变化趋势
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基于优化地理探测器的生态环境质量驱动力分析 被引量:1
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作者 牟凤云 黄淇 陈林 《水土保持研究》 CSCD 北大核心 2024年第1期440-449,共10页
[目的]克服生态环境质量(EQI)演化驱动因子在离散化过程中的随机性和主观性,优化传统地理探测器。[方法]利用相等间隔法、分位数法、自然断点法、几何间隔法和标准差法5种离散方法,对重庆市22项EQI演化驱动因子进行离散化,并结合地理探... [目的]克服生态环境质量(EQI)演化驱动因子在离散化过程中的随机性和主观性,优化传统地理探测器。[方法]利用相等间隔法、分位数法、自然断点法、几何间隔法和标准差法5种离散方法,对重庆市22项EQI演化驱动因子进行离散化,并结合地理探测器确定各因子的合理离散法与分类数,从而探究各驱动因子的驱动力大小和各驱动因子间交互模式。[结果](1)2005—2020年重庆市EQI处于I、Ⅲ和Ⅳ级的区县数量占比减少0.211,处于Ⅱ和V级的区县数量占比上升0.211,总体呈下降趋势,在空间上呈由西北向东南走向的梯度分布特征。(2)研究中各离散方法适用性排序为:自然断点法>几何间隔法>分位数法>相等间隔法>标准差法。不同因子适用的离散方法各异,应根据因子数据特征择优选取离散方法。(3)识别出影响重庆市EQI演化的关键驱动因子4个(0.37~0.49),主要驱动因子13个(0.14~0.33)、次要驱动因子4个(0.05~0.13)和其他因子1个(0.04),各驱动因子间交互作用均为双重增强或非线性增强。[结论]合理的离散化可以一定程度上克服连续数据离散化过程中的随机性和主观性,从而优化重庆市EQI演化驱动力探测结果。 展开更多
关键词 合理离散法 地理探测器 生态环境质量 驱动力 重庆市
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基于“生态-气候适应性-游憩”多功能耦合的复合绿地生态网络格局优化
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作者 周媛 黎贝 +5 位作者 李朋瑶 姚婧 陈明坤 唐密 张莉 陈娟 《生态学报》 CAS CSCD 北大核心 2024年第13期5854-5866,共13页
城市生态环境问题日益突出,如何构建多功能耦合的绿地生态网络格局是促进人居环境可持续发展的重要议题。以成都市为研究区,基于“源-汇”理论,综合运用形态学空间格局分析(Morphological Spatial Pattern Analysis,MSPA)、景观连通性... 城市生态环境问题日益突出,如何构建多功能耦合的绿地生态网络格局是促进人居环境可持续发展的重要议题。以成都市为研究区,基于“源-汇”理论,综合运用形态学空间格局分析(Morphological Spatial Pattern Analysis,MSPA)、景观连通性指数、电路理论等方法对生物多样性保护、热环境改善、游憩服务构建单因子网络,分析源地、廊道、生态战略点等空间要素特征,形成基于“生态-气候适应性-游憩”多层级、多功能复合生态网络优化格局。结果表明:(1)筛选出“源”-“汇”景观(生态159—29个,气候适应性30—14个,游憩208—40个)。生物迁徙廊道在研究区中部、西南部呈团簇状分布;气候适应性廊道呈中部集聚、东西稀疏的分布特征;游憩廊道相对密集,以中心城区为核心向四周扩散。(2)多层级“源-汇”景观网络中,总长度上,游憩廊道>生物迁徙廊道>气候适应性廊道;总面积上,生物迁徙廊道>游憩廊道>气候适应性廊道。一、二级廊道的适宜宽度为生态廊道200、100m,气候适应性廊道100、60m;游憩廊道60、30m。(3)叠加多目标廊道获得生态关键点753个,干扰点2371个。游憩源地中8.18%的面积应退让给生态廊道和气候适应性廊道。多功能耦合的生态网络优化格局可激活不同景观资源的潜在价值,对协调生态保护与城市发展的双向需求,实现绿地资源在城市空间中的最优配置具有重要意义。 展开更多
关键词 生物多样性保护 热环境改善 游憩服务 绿地生态网络 多功能耦合
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快速城镇化地区生态环境质量时空格局演变及对土地利用变化响应——以廊坊市北三县为例
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作者 武爱彬 程林 赵艳霞 《西北林学院学报》 CSCD 北大核心 2024年第1期169-176,共8页
对生态环境质量时空格局及其对土地利用变化的响应进行研究可为区域制定生态保护修复政策提供参考。通过构建遥感生态指数,对廊坊市北三县2000-2020年生态环境质量分布格局分析评价,利用地理加权回归模型探索生态环境质量变化对土地利... 对生态环境质量时空格局及其对土地利用变化的响应进行研究可为区域制定生态保护修复政策提供参考。通过构建遥感生态指数,对廊坊市北三县2000-2020年生态环境质量分布格局分析评价,利用地理加权回归模型探索生态环境质量变化对土地利用变化的响应。结果表明,北三县2000-2020年生态环境质量等级以“良”和“一般”为主,整体呈下降趋势,等级“较差”面积呈快速增长趋势。建设用地变化、土地利用强度变化和生态环境质量变化呈负相关关系,回归系数在空间上呈现较大的异质性;生态用地变化与生态环境质量变化呈正相关关系,回归系数在空间上异质性不强。城镇快速扩张的区域生态环境质量变化对建设用地变化和土地利用强度变化响应最显著。大量耕地向建设用地转变是区域生态环境变化的最主要影响因素,在国土空间规划中应划定城市边界,严格控制建设用地规模,提高集约节约利用水平,确保区域可持续发展。 展开更多
关键词 生态环境质量 遥感生态指数 土地利用变化 地理加权回归 廊坊北三县
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