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Transport of airborne particulate matters originating from Mentougou, Beijing, China

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China Particuology 2007年第6期5卷 408-413页

作者： Duoxing Yang Yongwei Han jixi gao Jesse Thé institute of Crust Dynamics CEA Beijing 100085 China Chinese Academy of Environmenial Sciences Beijing 100012 China Lakes Environmental Software Inc. 419-3 Phillips St. Waterloo ON N2L 3X2 Canada

In this study, a coupled regional air quality modeling system is applied to investigate the time spatial variations in airborne particulate matters （PM10）, originating from Mentougou to Beijing municipal area in the period of April 1-7, 2004, and the influences of complex terrain and meteorological conditions upon boundary layer structure and PM10 concentration distributions. An intercomparison of the performance with CALPUFF against the observed data is presented and an examination of scatter plots is provided. The statistics show that the correlation coefficient and STD between the modeled and observed data are 0.86 and 0.03, respectively. Analysis of model results illustrates that the pollutants emitted from Mentougou can be transported to Beijing municipal area along certain transport pathways, and PM10 concentration distributions show heterogeneity characteristics. Contributions of the Mentougou sources to the PM10 concentrations in Beijing municipal area are up to 0.1-15 μg/m^3.

关键词： Airborne particulate matters CALPUFF PM10 SMOKE Emission inventory

Effects of freezing intensity on soil solution nitrogen and microbial biomass nitrogen in an alpine grassland ecosystem on the Tibetan Plateau,China

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Journal of Arid Land 2016年第5期8卷 749-759页

作者： YANG Zhaoping gao jixi YANG Meng SUN Zhizhong Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and EngineeringNanjing University of Information Science & Technology Nanjing Institute of Environmental Sciences Ministry of Environmental Protection State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The change of freeze-thaw pattern of the Tibetan Plateau under climate warming is bound to have a profound impact on the soil process of alpine grassland ecosystem;however,the research on the impact of the freeze-thaw action on nitrogen processes of the alpine grassland ecosystem on the Tibetan Plateau has not yet attracted much *** this study,the impact of the freezing strength on the soil nitrogen components of alpine grassland on the Tibetan Plateau was studied through laboratory freeze-thaw simulation *** 0–10 cm topsoil was collected from the alpine marsh meadow and alpine meadow in the permafrost region of Beilu *** the experiment,the soil samples were cultivated at –10℃,–7℃,–5℃,–3℃ and –1℃,respectively for three days and then thawed at 2℃ for one *** results showed that after the freeze-thaw process,the soil microbial biomass nitrogen significantly decreased while the dissolved organic nitrogen and inorganic nitrogen significantly *** the freezing temperature was below –7℃,there was no significant difference between the content of nitrogen components,which implied a change of each nitrogen component might have a response threshold toward the freezing *** the freeze-thaw process can lead to the risk of nitrogen loss in the alpine grassland ecosystem,more attention should be paid to the response of the soil nitrogen cycle of alpine grasslands on the Tibetan Plateau to the freeze-thaw process.

关键词： freezing temperature microbial biomass nitrogen dissolved organic nitrogen inorganic nitrogen alpine grassland Tibetan Plateau

High Environmental Cost behind Low China Price

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Chinese Journal of Population,Resources and Environment 2007年第3期5卷 63-75页

作者： Fan Xiaoshan gao jixi Institute of Mountain Hazard and Environment Chinese Academy of Science ＆ Ministry of Water Conservancy Chengdu Sichuan 610041 China Regional Ecology Department Chinese Research Academy of Environmental Sciences Beijing 100012 China

China has won the name of the world factory being famous for exporting a great deal of and various kinds of low-price merchandise. However, most of Chinese exports are primary goods or manufactured products that create heavy pollution and require intensive use of resources. Chinese products go abroad, but their following harms stay behind. The article analyzes many obvious low-price facts in China and their concomitant terrible environmental results in detail, and points out that there are huge hidden troubles in the way of China’s sustainable development behind her seemingly flourishing economy.

关键词： low China price resource pollution

Evaluating changes in ecological land and effect of protecting important ecological spaces in China

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Journal of Geographical Sciences 2021年第9期31卷 1245-1260页

作者： gao jixi LIU Xiaoman WANG Chao WANG Yong FU Zhuo HOU Peng LYU Na Ministry of Ecology and Environment Center for Satellite Application on Ecology and Environment Beijing 100094China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

It is important to quantitatively analyze the effects of protection of important ecological spaces in China to ensure national ecological *** considering changes in the ecological land,this study examines the effects of protecting three types of important natural ecological spaces in China from 1980 to ***,considering important ecological spaces and their surroundings yields differences in the effects of protection between internal and external spaces,where this can provide a scientific basis for the categorization and zoning of China’s *** results show the following:(1)In 2018,the ratio of ecological land to important natural ecological spaces accounted for 92.64%.This land had a good ecological background that reflects the developmental orientation of important ecological spaces.(2)From 1980 to 2018,the area of ecological land in important ecological spaces shrank but the rate of reduction was lower than the national average,which shows the positive effect of regulating construction in natural ecological *** restorative effects of ecological projects to convert farmland into forests and grasslands have been *** expanded ecological land is mainly distributed in areas where such projects have been implemented,and the reduced area is concentrated in grain-producing areas of the Northeast China Plain and agricultural oases of *** the future,the government should focus on strengthening the management and control of these areas.(3)The area ratio of ecological land was the highest in national nature *** rate of reduction in its area was the lowest and the trend of reduction was the smallest in national nature reserves,which reflects differences in the status of ecological protection among different spaces.(4)The ratio of ecological land to important ecological spaces was higher than that in the surrounding external space,and the rate of reduction in it was ***,the effects of internal and external protection

关键词： ecological spaces ecological land spatial and temporal dynamic changes protection effect categorized and zoned governance

Key issues on watershed ecological security assessment

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Chinese Science Bulletin 2007年第A02期52卷 251-261页

作者： gao jixi ZHANG XiangHui JIANG Yun OU XiaoKun HE DaMing SHI JianBin Chinese Research Academy of Environmental Sciences Beijing 100012 China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China School of Resource Environment & Earth Science Yunnan University Kunming 650091 China Asian Intemational River Center Yunnan University Kunming 650091 China EU-China Biodiversity Programme Beijing 100044 China

有关分水岭基于关键问题的分析包括评价的题目，内容，和方法论的生态的安全评价，这篇论文指出那生态的安全应该在不同层次动态地被估计(例如分水岭和生态系统层次) 与是的人一起主要评价题目。功能的安全和结构的安全必须在分水岭被... 详细信息

有关分水岭基于关键问题的分析包括评价的题目，内容，和方法论的生态的安全评价，这篇论文指出那生态的安全应该在不同层次动态地被估计(例如分水岭和生态系统层次) 与是的人一起主要评价题目。功能的安全和结构的安全必须在分水岭被认为生态的安全评价。以便反映分水岭的全面、及时的安全地位， PSR (pressure-state-response ) 方法应该被采用。纵的范围峡区域(LRGR ) 作为一个例子被研究。分水岭的一个索引系统生态的安全评价被建议了，它包括结构的索引，功能的索引，压力和反应索引，并且生态的安全的状态在云南为 LRGR 被分析省。

关键词：生态安全生态环境分水岭评估方法

Tensile Elastic Modulus, Strength and Fracture of δ-Al_2O_(3f)/Al Alloy Composites

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Journal of Materials Science & Technology 2000年第5期16卷 475-480页

作者： GuoZheng KANG+, Qing gao and jixi ZHANG (Department of Applied Mechanics and Engineering, Southwest Jiaotong University, Chengdu 610031, China) Department of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

Based on the experimental and theoretical analysis, the tensile elastic modulus, strength and fracture characteristics of squeeze casting δ-Al2O3/Al alloy composites were studied. The fracture characteristics of composites were observed by SEM. The elastic modulus was predicted by the finite element method based on the energy equivalence principle, and the strength was predicted by the statistical integration average method using the maximum energy criterion of composite strength. In the prediction, the distribution density functions of the fiber's. orientation and length were considered. These functions were gained by experimental measurement. It is shown that the predicted results are in agreement with the experimental values well and the microstructure feature of composites controls the fracture characteristics.

关键词： Tensile Elastic Modulus Al2O

Emission of landfill gas in Qingdao, China

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Journal of Environmental Sciences 1996年第3期8卷 292-297页

作者： gao jixi Shen Yingwa Cao Hongfa Shu Jianmin(Institute of Ecology, Chinese Research Academy of Environmental Sciences,Beijing 100012, China) Institute of Ecology Chinese Res. Acad. of Environ. Sci. Beijing 100012 China

A study on landfill gas emission in Qingdao,China was carried out. The results showed that the generation of landfill gas with maximum methane concentration occurred several months after the refuse was disposed and the steady emission of landfill gas could remain two *** variation of landfill gas production was associated with temperature. In June, the emission of landfill gas rose gradually from morning to evening, but in September, it rose in the morning, and then fell in the afternoon. From June to August, the emission of landfill gas showed rising trend,but it declined quite quickly from September to December. In different seasons,the outflow rate of landfill gas varied from depth to depth in the refuse site. When earth temperature was higher in summer, the emission of landfill gas did not correspond with the depth of refuse sites, but when temperature fell in winter, and the temperature became a limited factor to the gas production,the outflow of landfill gas increased with increasing in depth of refuse piling.

关键词： landfill gas emission China

Review of challenges and strategies for balanced urban-rural environmental protection in China

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Frontiers of Environmental Science & Engineering 2015年第3期9卷 371-384页

作者： Beidou XI Xiaoguang LI jixi gao Ying ZHAO Hongliang LIU Xunfeng XIA Tianxue YANG Lieyu ZHANG Xuan JIA State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China School of Environment Beijing Normal University Beijing 100875 China Nanjing Institute of Environmental Sciences of State Environmental Protection Administration Nanjing 210042 China

With the rise of environmentalism in China, great efforts have been devoted to environmental protec- tion over the past several decades. Compared with urban environmental protection, rural environmental protection has not been attached enough importance in China due to the dual-track structure of socio-economic development. As a result, rural China is shouldering disproportionally heavy environmental burdens partly because of the differences and biases between urban and rural environmental protection seen in environmental policies, environ- mental rights and interests, environmental protection investment, and the environmental protection awareness of people. To eliminate the gap between rural and urban environmental protection, and achieve the goal of ＂balanced urban-rural environmental protection＂（BUREP）, government should consider mapping out proper policies and strategies. In this paper we put forward an innovative strategy of BUREP against the background of China＇s urban-rural environmental protection. First, we review the current status of rural environmental protection status and its challenges compared with urban environ- mental protection in China. Secondly, we analyzed the main driving factors and reasons deeply, and then we put forward the BUREP strategy base on the unequal status between urban and rural environment. Finally, we proposed the framework of BUREP. This study may serve as a scientific reference regarding decision-making in coordinating urban and rural environmental protection and in constructing the new countryside of China.

关键词： urban environment rural environment,balanced urban--rural environmental protection framework of balanced urban-rural environmental protection (BUREP)

Analysis of land use change and its driving force in the Longitudinal Range-Gorge Region

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Chinese Science Bulletin 2007年第A02期52卷 10-20页

作者： LI ZhengHai SONG GuoBao LU HaiYan BAO YaJing gao jixi WANG HaiMei XU Tian CHENG Yan Institute of Bio-Resources and Environment College of Life Science Dalian Nationalities University Dalian 116600 China College of Resources Science & Technology Beijing Normal University Beijing 100875 China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Innovation Base of Regional Ecology Chinese Research Academy of Environmental Sciences Beijing 100012 China Inner Mongolia Municipality Observatory Huhhot 010051 China e College of Life Sciences Inner Mongolia University Huhhot 010021 China College of Life Sciences Inner Mongolia University Huhhot 010021 China College of Ecological Environment Inner Mongolia Agricultural University H uhhot 010018 China

关于陆地使用度，陆地使用变化率以及各种各样的陆地使用的地区性的差别的研究录入西南纵的范围峡区域(LRGR ) 被执行了在上地区性并且县规模。从社会经济的看法，我们也在研究区域分析了陆地使用变化的开车机制和各种各样的驱动力的相... 详细信息

关于陆地使用度，陆地使用变化率以及各种各样的陆地使用的地区性的差别的研究录入西南纵的范围峡区域(LRGR ) 被执行了在上地区性并且县规模。从社会经济的看法，我们也在研究区域分析了陆地使用变化的开车机制和各种各样的驱动力的相应空间范围。研究结果显示在地区性的规模上，农田，森林和草地在 LRGR，和草地严厉地衰退的陆地使用表演的结构的变化填写陆地使用的主要身体，农田增加和森林保持稳定。在县规模上，陆地使用被那陆地使用水平描绘是相对低的，并且陆地使用度，全面变化率和相对变化在不同陆地使用类型之中评价仍然存在。由分析，在 LRGR 的陆地使用变化被投资主要驾驶人力和物理资源，社会经济产量水平，自然灾难骚乱的紧张和工人的教育水平的紧张。然而， regionalism 在不同驱动力类型的影响范围存在。

关键词：分析方法动力系统纵向岭谷区土地