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Abell团角分布的二级矩,三级矩以及空间三点相关函数
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作者 景益鹏 张家铝 《天文学报》 CSCD 北大核心 1989年第3期241-248,共8页
本文用"胞内计数"方法对北天区的富度R≥1的Abell团角分布的二级矩和三级矩作了统计,并由此得到了Abell团的空间三点相关函数;同时,本文还对D≤4,R≥1的Abell团红移样品的三点相关函数进行了统计.这些统计分析得到的结果与通... 本文用"胞内计数"方法对北天区的富度R≥1的Abell团角分布的二级矩和三级矩作了统计,并由此得到了Abell团的空间三点相关函数;同时,本文还对D≤4,R≥1的Abell团红移样品的三点相关函数进行了统计.这些统计分析得到的结果与通过估计红移值对四组子样品进行统计分析所得到的结果是一致的,从而进一步说明,星系和Abell团的三点相关函数可用同一个普遍的标度形式来描述. 展开更多
关键词 北天区 团角 级矩 空间 相关函数
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Spatial connectivity and distribution of landscape type in the natural secondary forests of eastern mountainous region,northeast China——a case study of Mao'ershan region in Heilongjiang Province
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作者 李淑娟 隋玉正 +2 位作者 冯海清 王凤友 李玉文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期141-144,i003,共5页
Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculate... Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculated with ARC/INFO software for Mao'ershan region. The spatial distribution of the landscape of the region was analyzed. The results showed that the landscape connectivity index of non-woodland was significantly higher than that of woodland. The landscape connectivity index of natural forest was nearly equal to zero, which means its fragmentation degree is high. The nearest neighbor index of plantation was lower than that of natural forest and non-forestland. Among the man-made forests, the distance index of the coniferous mixed plantation is the lowest, and its pattern is nearly glomeration. The landscape pattern of natural forest presented nearly random distribution. Among non-forest land, the distance index of cut blank was the lowest, and its pattern was also nearly glomeration. Keywords Landscape type - Landscape pattern - Nearest neighbor index - Landscape connectivity index - Natural secondary forest - Northeast China CLC number S759.92 Document code A Foundation item: This paper was supported by the Key Project of State Department of Science Technology (2002BA515B040).Biography: LI SHu-juan (1977), female. Lecture in Ocean University of China, Qingdao 266003, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Landscape type Landscape pattern Nearest neighbor index Landscape connectivity index Natural secondary forest Northeast China
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Water Requirements and Irrigation Scheduling of Spring Maize Using GIS and CropWat Model in Beijing-Tianjin-Hebei Region 被引量:18
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作者 FENG Zhiming LIU Dengwei ZHANG Yuehong 《Chinese Geographical Science》 SCIE CSCD 2007年第1期56-63,共8页
Due to the over use of available water resources, it has become very important to define appropriate strategies for planning and management of irrigated farmland. In this paper, Beijing-Tianjin-Hebei (Jing-Jin-Ji) reg... Due to the over use of available water resources, it has become very important to define appropriate strategies for planning and management of irrigated farmland. In this paper, Beijing-Tianjin-Hebei (Jing-Jin-Ji) region was chosen as the case study area for its special political and economic status and its severe water problem. To achieve effective planning, the information about crop water requirements, irrigation withdrawals, soil types and climatic conditions were obtained in the study area. In the meantime, a GIS method was adopted, which extends the capabilities of the crop models to a regional level. The main objectives of the study are: 1) to estimate the spatial distribution of the evapotranspiration of spring maize; 2) to estimate climatic water deficit; 3) to estimate the yield reduction of spring maize under different rainfed and irrigated conditions. Based on the water deficit analysis, recommended supplemental irrigation schedule was developed using CropWat model. Compared to the rainfed control, the two or three times of supplemental water irrigated to spring maize at the right time reduced the loss of yield, under different scenarios. 展开更多
关键词 spring maize climatic water deficit irrigation schedule
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STRUCTURE AND RESTRUCTURING OF BEIJING-TIANJIN-HEBEI MEGALOPOLIS IN CHINA 被引量:1
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作者 YU Tao-fang 《Chinese Geographical Science》 SCIE CSCD 2006年第1期1-8,共8页
Scott proposes to use the term global city-regions to designate the phenomena that bear some resemblance to the "world cities" firstly identified by Hall and Friedmann and Wolff, and to the "global citi... Scott proposes to use the term global city-regions to designate the phenomena that bear some resemblance to the "world cities" firstly identified by Hall and Friedmann and Wolff, and to the "global cities" of Sassen but whose essential social logic and contextual characteristics have evolved considerably since these pioneering studies were published. In simple geographical terms, a global city-region can be refered to comprise any major metropolitan area or any contiguous set of metropolitan areas together with a surrounding hinterland of variable extent-itself a locus of scattered urban settlements-whose internal economic and political affairs are bound up in intricate ways in intensifying and far-flung extra-national relationships. Scott refers to these extra-national relationships as a symptom of "globalization". As economic motors and political actors, the global city regions have been regarded as crucial parts of development strategies in China. In the "Eleventh Five-year Plan" issued by the National Development and Reform Commission of P. R. China, the Beijing-Tianjin-Hebei Province (Jing-Jin-Ji) region, one of the typical megalopolises or global city regions in the East Coastal China is paid more attention. This paper first analyzes the regional structure of the Jing-Jin-Ji region based on data of the fifth national population census of China. And then through the changes of the population growth, the dynamic process and mechanisms of the regional restructuring in the Jing-Jin-Ji is explored and discussed. 展开更多
关键词 regional structure regional restructuring Beijing-Tianjin-Hebei (Jing-Jin-Ji)
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A Numerical Study of the Urban Intensity Effect on Fog Evolution in the Beijing-Tianjin-Hebei Region 被引量:5
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作者 LIANG Zhao-Ming GAO Shou-Ting SUN Ji-Song 《Atmospheric and Oceanic Science Letters》 2012年第3期240-245,共6页
The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy p... The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy parameterization-building energy model (UCP- BEM) urban physics scheme. The experiments were designed with a focus on the influence of different urban intensities, which are represented by a different fractional coverage of natural land, buildings, and energy consumption inside buildings in an urban environment. The results of this study indicate that urban areas notably influence fog evolution when natural land is reduced to a small fraction (e.g., less than 10%). Developed land changes fog evolution through urban effects. Higher urban intensity (HUI) generally results in warmer temperatures and lower wind speeds throughout the day, while inhibiting morning specific humidity loss and afternoon specific humidity gain because of the HUI effect on surface heat flux, surface roughness, and surface moisture flux. HUI leads to later and weaker liquid water content formation, with a higher liquid water content base, primarily due to its effect on near surface temperatures. This finding implies that HUI may inhibit the conditions for fog formation. In addition, urban areas with equal natural and developed land coverage seem to greatly enhance the upward surface moisture flux, which is attributed to the combination of a relatively large potential evaporation on developed land and an ample moisture supply from natural land. As a result, the specific humidity increases in the afternoon. 展开更多
关键词 numerical study urban intensity effect FOG the Beijing-Tianjin-Hebei region
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Carbon sequestration of plantation in Beijing-Tianjin sand source areas 被引量:3
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作者 LIU Xiu-ping ZHANG Wan-jun +2 位作者 CAO Jian-sheng YANG Bai CAI Yan-jiang 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2148-2158,共11页
The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust haz... The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust hazards. The carbon sequestration dynamics can be used to assess the ecological effects of an ecological restoration project. Here, we conducted vegetation and soil study to assess the carbon sequestration in the plantations with 10 years old stands in Beijing-Tianjin sand source areas. The results at the site scales indicated that the average net increase of plantation ecosystem carbon stock was 33.8 Mg C ha^(-1), with an annual increase rate of 3.38 Mg C ha^(-1) yr^(-1). The average net increase of carbon varied among regions, vegetation types, and forest management activities. Soil bulk density in the top soil decreased slightly after 10-year implementation of the project. Coniferous forests and shrubs are suitable plant species for sand source areas.Natural restoration in the plantations is a practical and feasible and promising approach for enhancing ecosystem carbon sequestration potential. 展开更多
关键词 AFFORESTATION Carbon sequestration Carbon density Forest management RESTORATION Sand source control
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Landscape pattern and fragmentation of natural secondary forests in the eastern mountainous region, northeast China: A case study of Mao'ershan forests in Heilongjiang Province 被引量:1
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作者 LISHu-juan SUIYu-zheng +2 位作者 SUNZhi-hu WANGFeng-you LIYu-wen 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期35-38,i002-i003,共6页
Mao'ershan region is a representative natural secondary forested region in the eastern mountainous region, northeast of China.. Under the support of ARC/INFO and GIS technology, the landscape shape and fragment in... Mao'ershan region is a representative natural secondary forested region in the eastern mountainous region, northeast of China.. Under the support of ARC/INFO and GIS technology, the landscape shape and fragment indices of Mao'ershan experimental plantation were studied by combining the forest type map (1:10000), which was drawn from the aerial photographs (1999), field investigation (1999) and soil utilized map (1:10000). The results showed that the shape index and shape fragment index of natural landscape were higher than those of artificial landscapes and landscape patch fragment index depended on the number of patches. The natural forest had complex shape, suffering little jamming, and its shape index was higher than that of artificial forest. The manual controlled landscape (e.g. nursery, cropland and cutting blank) had regular shape, and its shape index was smaller. The fragment index of patches in natural forest was higher than that of artificial forest. The soft broad-leaved had the highest fragment index of patch amount. 展开更多
关键词 Landscape PATCH Shape index Fragment index
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Neogene coupling between Kuqa Basin and Southern Tien Shan Orogen, Northwestern China 被引量:3
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作者 何光玉 陈汉林 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期970-975,共6页
Based on the sedimentary and subsiding features of Kuqa foreland basin, this paper presents the following characteristics of Neogene coupling relationship between Kuqa Basin and Southern Tien Shan Orogen, Northwester... Based on the sedimentary and subsiding features of Kuqa foreland basin, this paper presents the following characteristics of Neogene coupling relationship between Kuqa Basin and Southern Tien Shan Orogen, Northwestern China: (1) The Southern Tien Shan Orogen underwent Neogene uplifting of 4 km in height and the Kuqa Basin underwent Neogene subsidence of 4?6 km in depth accordingly beginning in 25 Ma; (2) The Southern Tien Shan Orogen moved continuously toward the Kuqa Basin, with largest structural shortening rate of greater than 53.7%, and the north boundary of the Kuqa Basin retreated continuously southward accordingly since the Miocene; (3) There are two subsidence centers with high subsiding rates and large subsiding extent, located in the eastern and western Kuqa Basin respectively, with the subsiding maximizing in the deposition period of Kuqa Formation. 展开更多
关键词 Kuqa Basin Southern Tien Shan Coupling between basin and orogen NEOGENE
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Cassini Growth of Population Between Two Metropolitan Cities——A Case Study of Beijing-Tianjin Region,China 被引量:1
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作者 ZONG Yueguang YANG Wei +1 位作者 MA Qiang XUE Song 《Chinese Geographical Science》 SCIE CSCD 2009年第3期203-210,共8页
The existing models of population distribution often focus on the region with a single city or even multiple centers, and lack the detailed explorations of the common and special type of urbanization areas with two ce... The existing models of population distribution often focus on the region with a single city or even multiple centers, and lack the detailed explorations of the common and special type of urbanization areas with two centers. Taking Beijing-Tianjin region of China, which is a distinct dual-nuclei metropolitan area in the world, as an example and choosing Landsat-5 TM image in 2005, population, etc. as the data, this paper devotes to comprehending and illustrating a model of Cassini growth of population between the two metropolitan cities through the research of spatial population distribution pattern, aided with RS and GIS techniques. Main technical processes include Kriging interpolation of the population data and character simulation of the Cassini ovals. According to the calculation of a/b, a key characteristic index of Cassini growth model, the spatial structures of population distribution were given. When a/b〈 1, it is a curve with two separated loops with a population density more than 3000 persons/km^2. When a/b=1, it is a lemniscate curve with a population density about 3000 persons/km^2. When 1〈a/b〈 √2, it is a dog-bone shaped concave curve with a population density between 500-3000 persons/km^2. When a/b= √2, it is an oblate curve with a population density about 500 persons/km^2. When a/b〉 √2, there is an oval-shaped convex curve with a population density less than 500 persons/km^2. The results show that owing to the combined action and influence of the regional dual-nuclei, the population distribution of Beijing-Tianjin region is in accord with Cassini model significantly. Therefore, there is Cassini growth of population between the two metropolitan cities in Beijing-Tianjin region. In addition, the process of Cassini growth has extraordinarily instructive significance for judging the development stages of the dual-nuclei metropolitan areas. 展开更多
关键词 metropolitan city dual-nuclei metropolitan area urban spatial growth Cassini growth model Beijing-Tianjin region China
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Technology of gas drainage and utilization in Huaibei mining area 被引量:3
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作者 LI Wei XU Rui 《Journal of Coal Science & Engineering(China)》 2009年第3期278-283,共6页
With the characteristics of coal seam geology and gas occurrence,a'ground-underground' integrated gas drainage method was formed,which can relieve gaspressure and increase permeability by mining the protection... With the characteristics of coal seam geology and gas occurrence,a'ground-underground' integrated gas drainage method was formed,which can relieve gaspressure and increase permeability by mining the protection seams in conditional regions.After coal seam gas drainage,high gas outburst seam was converted to low gas safetyseam.In the coal face mining process,safety and high efficient coal mining were realizedby the measure of gas-suction over mining.In addition to the drainage gas for civil gasand gas power generation,the Huaibei Mining Group has actively carried out research onthe utilization technology of methane drainage by ventilation.On the one hand,it can saveprecious energy;on the other hand,it can protect the environment for people's survival.In2007,the amount of coal mine gas drainage was 120 hm3;the rate of coal mine gasdrainage was 44%.Compared with the year 2002,the amount of coal mine gas drainageincreased by two times.Meanwhile,the utilization rate of gas increased rapidly. 展开更多
关键词 gas drainage gas utilization Huaibei mining area
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Measuring Social Vulnerability to Natural Hazards in Beijing-Tianjin-Hebei Region,China 被引量:2
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作者 HUANG Jianyi SU Fei ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2015年第4期472-485,共14页
Social vulnerability in this study represents the differences between the capacity to cope with natural hazards and disaster losses suffered within and between places.The assessment of social vulnerability has been re... Social vulnerability in this study represents the differences between the capacity to cope with natural hazards and disaster losses suffered within and between places.The assessment of social vulnerability has been recognized as a critical step in understanding natural hazard risks and enhancing effective response capabilities.This article presents an initial study of the social vulnerability of the Beijing-Tianjin-Hebei(B-T-H) Region in China.The goal is to replicate and test the applicability of the United States Social Vulnerability Index(So VI) method in a Chinese cultural context.Thirty-nine variables adapted from the So VI were collected in relation to two aspects:socioeconomic vulnerability and built environment vulnerability.Using factor analysis,seven factors were extracted from the variable set:the structure of social development,the level of economic and government financial strength,social justice and poverty,family structure,the intensity of space development,the status of residential housing and transportation,and building structure.Factor scores were summed to get the final So VI scores and the most and least vulnerable units were identified and mapped.The highest social vulnerability is concentrated in the northwest of the study area.The least socially vulnerable areas are mainly distributed in the Beijing,Tianjin and Shijiazhuang core urban peripheral and central city areas of the prefecture-level cities.The results show that this method is a useful tool for revealing places that have a high level of vulnerability,in other words,areas which are more likely to face significant challenges in coping with a large-scale event.These findings could provide a scientific basis for policy making and the implementation of disaster prevention and mitigation in China. 展开更多
关键词 natural hazards social vulnerability factor analysis Beijing-Tianjin-Hebei Region
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Recent Climate Trends on the Northern Slopes of the Tianshan Mountains, Xinjiang, China 被引量:3
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作者 ZHANG Hongfeng OUYANG Zhiyun ZHENG Hua WANG Xiaoke 《Journal of Mountain Science》 SCIE CSCD 2009年第3期255-265,共11页
In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of nort... In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of northwestern China. This paper provides an assessment of the changes in temperature and precipitation in the historical records of climate on the northern slopes of the eastern Tianshan Mountains. A Mann-Kendall nonparametric trend and Sen's tests are employed to analyze the interannual changes and innerannual variability in temperature and precipitatiofi in the regions of low to high altitude. The present study finds that the largest increases in annual temperature are observed at stations in the low altitude regions. The significant increasing trends in temperature tend to occur mainly in late winter and early spring at stations from middle to high altitude, but in summer and autumn at stations of low altitudes. The increasing trends in annual precipitation are found from the middle to high altitude areas, but decreasing trends are found in the low altitude areas. The significant increasing trends in precipitation occur mostly in winter and earlier spring at stations from the middle to high altitudes, while the increasing and decreasing trend coexists at stations of low altitude with most of the significant trend changes occurring in March, June and August. 展开更多
关键词 Mountainous region Climate change Temperature PRECIPITATION China
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Relocation of Earthquakes in the Northeastern Tianshan Mountains Area and Improvement of Local 1-D Crustal Velocity Model 被引量:1
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作者 Sun Anhui Chen Qifu +2 位作者 Chen Yong Li Gang Zhang Zhiqiang 《Earthquake Research in China》 2012年第3期321-334,共14页
We apply three methods to relocate 599 earthquake events that occurred from August 2004 to August 2005 in the northeastern Tianshan Mountains area ( 85°30' ~ 88°30'E,43°00' ~ 44°40... We apply three methods to relocate 599 earthquake events that occurred from August 2004 to August 2005 in the northeastern Tianshan Mountains area ( 85°30' ~ 88°30'E,43°00' ~ 44°40' N ) by using travel times recorded by regional seismic network and 10 portable seismic stations deployed around the Urumqi city. By comparing the reliability of different results,we determined a suitable location method,and an improved 1-D crustal velocity model of the study area. The uncertainty of earthquake location is significantly reduced with combined data of seismic network and portable stations. The relocated events are clearly associated with regional tectonics of the northeastern Tianshan Mountains area, and are also in agreement with the existence of active faults imaged by deep seismic reflection profile. The relocated seismicity discovers some potential traces of buried active faults,which need to be validated further. 展开更多
关键词 Earthquake relocation Velocity model The northeastern Tianshan Mountains area Active faults
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Hebei Talents Development Strategy under the Background of Talents Integration in Beijing-Tianjin-Hebei Region
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《International English Education Research》 2014年第1期19-23,共5页
As the development of productive forces, the most critical and most active factors in people is the fimdamental driving force of regional economic sustainable development and cooperation has a vital role in regional e... As the development of productive forces, the most critical and most active factors in people is the fimdamental driving force of regional economic sustainable development and cooperation has a vital role in regional economic development Only speed up regional economic cooperation and enforce the integration of regional talent development, can the Beijing-Tianjin-Hebei region achieves rapid development, and become China' s third largest economic growth pole, following the Pearl River Delta and Yangtze River Delta. Based on reviewing the integration process of the integration of regional talent development in the Beijing-Tianjin-Hebci region, this paper further analyze differences in the economic development status, the level of human capital, wage levels, employment status, and the development of educational science and technology among Hebei Province, Beijing and Tianjin, and concludes talent development strategy for Hebei Province replying the personnel integration of Beijing, Tianjin and Hebei Province. 展开更多
关键词 BEIJING-TIANJIN-HEBEI Regional integration Level of human capital.
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Spheres of Urban Influence and Factors in Beijing-Tianjin-Hebei Metropolitan Region Based on Viewpoint of Administrative Division Adjustment 被引量:3
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作者 ZHU Jianhua CHEN Xi CHEN Tian 《Chinese Geographical Science》 SCIE CSCD 2017年第5期709-721,共13页
The coordinated development of Beijing, Tianjin and Hebei has been elevated as China's important strategy. And, the priority in considering how to bring the maximum effect of their coordinated development into pla... The coordinated development of Beijing, Tianjin and Hebei has been elevated as China's important strategy. And, the priority in considering how to bring the maximum effect of their coordinated development into play is to delineate the spheres of urban influence with regard to the cities in the Beijing-Tianjin-Hebei Metropolitan Region. By building an evaluation index system of urban comprehensive strength, this paper applies the principal component analysis method to determine centrality strength of the cities, and the breakpoint theory and weighted Voronoi diagram to identify the spheres of urban influence in all central cities of the region. Results show that 13 central cities within the region greatly differ in strength, which can be classified into four tiers and that the spheres of urban influence do not have a high goodness of fit with administrative jurisdiction scope. Cities like Beijing, Tianjin, Shijiazhuang and Handan have larger spheres of urban, spheres of urban influence in Tangshan and Qinhuangdao are basically consistent with their administrative jurisdiction scopes, and seven cities including Langfang and Baoding have smaller spheres of urban influence. So according to these cities' comprehensive strength and spheres of influence, the region can be divided into five plates: Beijing, Tianjin, Shijiazhuang, Tangshan and Handan. The major influence factors for inconsistency between spheres of urban influence and spheres of jurisdiction include difference in urban administrative ranking, small number of central cities with weak strength, discrepancy in the number of counties under jurisdiction, unreasonable spheres of jurisdiction and diversity in topographical conditions. In order to solve the imbalance in the spheres of urban influence and those of jurisdiction and better facilitate the coordinated development of the region, it is advised to adjust administrative areas so as to obtain more optimized urban spatial layout and more reasonable urban scale hierarchy system. 展开更多
关键词 spheres of urban influence urban comprehensive strength adjustment of administrative divisions weighted Voronoi diagram Beijing-Tianjin-Hebei Metropolitan Region
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Did Ecological Engineering Projects Have a Significant Effect on Large-scale Vegetation Restoration in Beijing-Tianjin Sand Source Region, China? A Remote Sensing Approach 被引量:6
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作者 LI Xiaosong WANG Hongyan +2 位作者 ZHOU Shufang SUN Bin GAO Zhihai 《Chinese Geographical Science》 SCIE CSCD 2016年第2期216-228,共13页
Aiming for the restoration of degraded ecosystems, many ecological engineering projects have been implemented around the world. This study investigates the ecological engineering project effectiveness on vegetation re... Aiming for the restoration of degraded ecosystems, many ecological engineering projects have been implemented around the world. This study investigates the ecological engineering project effectiveness on vegetation restoration in the Beijing-Tianjin Sand Source Region(BTSSR) from 2000 to 2010 based on the rain use efficiency(RUE) trend in relation to the land cover. More than half of the BTSSR experienced a vegetation productivity increase from 2000 to 2010, with the increasing intensity being sensitive to the indicators chosen. A clear tendency towards smaller increasing areas was shown when using the net primary productivity(NPP, 51.30%) instead of the accumulated normalized difference vegetation index(59.30%). The short-term variation in the precipitation and intra-seasonal precipitation distribution had a great impact on the remote sensing-based vegetation productivity. However, the residual trends method(RESTREND) effectively eliminated this correlation, while incorporating the variance and skewness of the precipitation distribution increased the models′ ability to explain the vegetation productivity variation. The RUE combined with land cover dynamics was valid for the effectiveness assessment of the ecological engineering projects on vegetation restoration. Particularly, the result based on growing season accumulated normalized difference vegetation index(ΣNDVI) residuals was the most effective, showing that 47.39% of the BTSSR experienced vegetation restoration from 2000 to 2010. The effectiveness of the ecological engineering projects differed for each subarea and was proportional to the strength of ecological engineering. The water erosion region dominated by woodland showed the best restoration, followed by the wind-water erosion crisscross regions, while the wind erosion regions dominated by grassland showed the worst effect. Seriously degraded regions still cover more area in the BTSSR than restored regions. Therefore, more future effort should be put in restoring degraded land. 展开更多
关键词 vegetation restoration ecological engineering rain use efficiency(RUE) residual trends method(RESTREND) Beijing-Tianjin Sand Source Region(BTSSR)
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Potential of Cooperation on Oil & Gas Market in Northeast Asia
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作者 Guan Bo 《China Oil & Gas》 CAS 2015年第4期23-28,共6页
There is a great potential of both supply and consumption in oil & gas market in Northeast Asia, and the prospects of further cooperation is very broad. Sino-Russia cooperation on oil & gas will lay a crucial founda... There is a great potential of both supply and consumption in oil & gas market in Northeast Asia, and the prospects of further cooperation is very broad. Sino-Russia cooperation on oil & gas will lay a crucial foundation for building a regional oil & gas market, and an increasingly opened trading system for oil & gas will also meet Japan and South Korea's need in building a diversified and stable assurance system of oil & gas supply. The strategic role played by Kozmino Port in Far East Russia and Shanghai oil and gas trading platform in China will be highlighted. Competition and cooperation through market mechanism will help to activate the interactions of resource flow and capital flow in Northeast Asia region, thus can also help energy consuming countries in the region to promote their disclosure power in global pricing system and gradually eliminate the Asian Premium. 展开更多
关键词 Oil trade Internationalization of Renminbi (RMB) Northeast Asia COOPERATION RUSSIA Kozmino Port
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Rethinking the Power Shortage of China in 2011
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作者 Qing Lei Huo Yalin Li Dawei 《Electricity》 2012年第1期7-13,共7页
As the opening year of the "Twelfth Five-Year Plan," driven by the steady and fast economic growth, the year of 2011 saw China's rising demand for electricity, resulting in regional power shortages. Sub)ected to m... As the opening year of the "Twelfth Five-Year Plan," driven by the steady and fast economic growth, the year of 2011 saw China's rising demand for electricity, resulting in regional power shortages. Sub)ected to multiple factors such as the weather conditions, the contradictions between coal supply and power generation and the structural problems in the power system, power supply shortage across the nation became increasingly critical At the same time, the Northeast and Northwest China, plus Inner Mongolia, often experienced power generation surplus and difficulties in sending power to other regions. This paper reviews the overall situation of the national electric power supply in 2011, elaborates on the current contradictions in the power demand and supply and presents an in-depth analysis of causes and corresponding countermeasures. 展开更多
关键词 power supply power demand power shortage
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On the Governance of the Arctic Region under the Tragedy of the Commons
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作者 Jiang Xiumin Liang Yiwen 《Contemporary International Relations》 2018年第4期134-148,共15页
Because of global climate change,the natural environment is rapidly changing in the Arctic.The large amount of sea ice melting in the Arctic can lead to a great increase in the use of the world’s natural resources.Th... Because of global climate change,the natural environment is rapidly changing in the Arctic.The large amount of sea ice melting in the Arctic can lead to a great increase in the use of the world’s natural resources.This thesis focuses on the exploration and utilization of public waters in the Arctic region based on the economic theory of the Tragedy of the Commons,analyzes the current situation of Arctic governance,and predicts potential problems in the Arctic region,mainly including overfishing and environmental problems caused by coal and natural gas exploitation.Additionally,it makes an in-depth analysis on the current Arctic governance model based on the Arctic Council,and finally proposes some countermeasures and suggestions for Arctic governance. 展开更多
关键词 Tragedy of the Commons Arctic region Arctic governance
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Attribution of PM_(2.5) exposure in Beijing-Tianjin-Hebei region to emissions:implication to control strategies 被引量:18
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作者 Xin Li Qiang Zhang +10 位作者 Yang Zhang Lin Zhang Yuxuan Wang Qianqian Zhang Meng Li Yixuan Zheng Guannan Geng Timothy J.Wallington Weijian Han Wei Shen Kebin He 《Science Bulletin》 SCIE EI CAS CSCD 2017年第13期957-964,共8页
The Beijing-Tianjin-Hebei (BTH) region is one of the most heavily polluted regions in China, with both high PM2.5 concentrations and a high population density. A quantitative source-receptor relationship can provide... The Beijing-Tianjin-Hebei (BTH) region is one of the most heavily polluted regions in China, with both high PM2.5 concentrations and a high population density. A quantitative source-receptor relationship can provide valuable insights that can inform effective emission control strategies. Both source appor- tionment (SA) and source sensitivity (SS) can provide such information from different perspectives. In this study, both methods are applied in northern China to identify the most significant emission cate- gories and source regions for PMz5 exposure in BTH in 2013. Despite their differences, both models show similar distribution patterns for population and simulated PM2.5 concentrations, resulting in overall high PM2.5 exposure values (approximately 110 Ixg/m3) and particularly high exposure values during the win- ter (approximately 200 ktg/m3). Both methods show that local emissions play a dominant role (70%), with some contribution from surrounding provinces (e.g., Shandong) via regional transport. The two methods also agree on the priority of local emission controls: both identify industrial, residential, and agricultural emissions as the top three categories that should be controlled locally. In addition, the effect of control- ling agricultural ammonia emissions is approximately doubled when the co-benefits of reducing nitrate are considered. The synthesis of SA and SS for addressing specific categories of emissions provides a quantitative basis for the development of emission control strategies and policies for controlling PM2.5 in China. 展开更多
关键词 PM2.5 exposureSource apportionmentSource sensitivityControl priorityChina
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