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Determinants of Farmers’ Perception of Climate Change: A Case Study from the Coastal Region of Bangladesh 被引量:3
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作者 Mohammed Nasir Uddin Wolfgang Bokelmann Emily Shea Dunn 《American Journal of Climate Change》 2017年第1期151-165,共15页
Socio-economic conditions of farmers, especially in the coastal region in Bangladesh, have been severely affected because of climate change. This study was focused on analyzing the farmers’ perception of climate chan... Socio-economic conditions of farmers, especially in the coastal region in Bangladesh, have been severely affected because of climate change. This study was focused on analyzing the farmers’ perception of climate change by examining three vital issues: (1) description of the socioeconomic characteristics of farmers;(2) reporting on the perception of farmers experiences with climatic change;and (3) identification of the socio-economic factors associated with farmers’ perception of climate change. The study area encompasses three villages within the coastal region (Sathkhira district) of Bangladesh, a geographic region where climate change literature has highlighted as prone to accelerated degradation. A logit model, along with weighted indexes for ranking and descriptive statistics, was used to analyze the result of 100 farmers surveyed by questionnaire. We found that the majority of the farmers (88%) perceived changes in climatic conditions. Almost all farmers indicated increases in temperature, droughts, floods, cyclones, salinity level and decreasing rainfall over the last 20 years. The logit model explained that out of the nine factors surveyed;education, family size, farm size, family income, farming experiences and training received were significantly related and influential factors to perception of climate change. Therefore, government and non-governmental organizations are recommended to push forward with interventions, especially focusing on identified factors, in order to strengthen the farmers’ capacity to battle against climate change effects. 展开更多
关键词 Determinants FARMERS PERCEPTION CLIMATE Change coastal region BANGLADESH
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Research on the Variation of Population Distribution and Its Characteristics Based on Spatial Autocorrelation Method: A Case Study of Poyang Lake Region in Jiangxi Province
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作者 Luo Hui Yang Weichun 《Chinese Journal of Population,Resources and Environment》 2010年第4期76-78,共3页
According to Statistical Yearbook of Jiangxi Province(2001~2006),We analyze the time-space variation of population distribution of Poyang Lake region from the two points of view.The former is quality of population,wh... According to Statistical Yearbook of Jiangxi Province(2001~2006),We analyze the time-space variation of population distribution of Poyang Lake region from the two points of view.The former is quality of population,which involves culture structure,occupational structure,age structure and sex structure of population.The latter is quantity of population,which only involves the amount of population.Furthermore,we can reveal the internal relations and action mechanism of variation of population distribution by analyzing the regional economic development,population urbanization,land use and ecological landscape of Poyang Lake region.It is important to provide help for region planning,ecological landscape planning and environmental protection by correct understanding the man-land relationship of natural-human ecosystem in Poyang Lake region. 展开更多
关键词 population distribution spatial autocorrelation changing characteristics Poyang Lake region
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Vegetation Coverage Changes in the West Qinling Region from 2000 to 2010:A Case Study of Longnan City
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作者 Ming FANG Qiuqiu LI +1 位作者 Chuansheng WANG Meng LI 《Asian Agricultural Research》 2016年第8期81-85,90,共6页
As the main content of terrestrial ecosystem study,vegetation coverage change has gained extensive attention in the process of global climate change and sustainable development recently.Based on MODIS NDVI data from J... As the main content of terrestrial ecosystem study,vegetation coverage change has gained extensive attention in the process of global climate change and sustainable development recently.Based on MODIS NDVI data from June to October during 2000-2010,taking Longnan City as a case area,this paper develops the calculation method of vegetation coverage(VC) by using Pixel Dichotomy model and analyzes the spatial-temporal variation of vegetation coverage in the West Qinling region by using simple linear regression and standard deviation method.The results show that vegetation coverage remains stable and is significantly correlated with temperature and precipitation during the decade.The vegetation coverage of 90% of study area shows stability with small annual variation and also is consistent with the spatial distribution of forest land;the vegetation coverage in the remaining study areas shows a growing trend with significant variation and also is consistent with the spatial distribution of farmland and grassland,especially in Huicheng Basin,Xili Basin and adret slope of Bailongjiang River Valley,indicating that Project about the Conversion of Degraded Farmland into Forest has made a great contribution to vegetation coverage increase.This paper proves the effect of ecology construction in the West Qinling region since the late 20 th century.All the findings also provide references for local ecological environment construction and sustainable development. 展开更多
关键词 Vegetation coverage spatial and temporal change West Qinling region
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Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China 被引量:1
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作者 CUI Yulong YANG Liu +1 位作者 XU Chong ZHENG Jun 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1564-1580,共17页
In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous ter... In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corresponding rise. In terms of spatial distribution, the rainfall-triggered landslides primarily occurred in the northeastern part of the study area, particularly in regions characterized by complex topography such as Shanzao Village in Yantan Town, Xixia Township, and Shangzhang Township. The research findings offer crucial data on the rainfallinduced landslides triggered by Typhoon Lekima, shedding light on their spatial distribution patterns. These findings provide valuable references for mitigating risks and planning reconstruction in typhoon-affected area. 展开更多
关键词 Typhoon rainfall Landslide characteristics spatial distribution Southeast coastal region
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Quantitative analysis of the dynamic change and spatial differences of the ecological security: a case study of Loess Plateau in northern Shaanxi Province 被引量:5
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作者 LI Jing REN Zhiyuan ZHOU Zixiang 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期251-256,共6页
Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecologica... Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecological carrying capacity and ecological surplus/loss in 1986-2002 on the Loess Plateau in northern Shaanxi Province. What is more, this paper has put forward the concept of ecological pressure index, set up ecological pressure index models, and ecological security grading systems, and the prediction models of different ecological footprints, ecological carrying capacity, ecological surplus and ecological safety change, and also has assessed the ecological footprint demands of 10,000 yuan GDE The results of this study are as follows: (1) the ecological carrying capacity in northern Shaanxi shows a decreasing trend, the difference of reducing range is the fastest; (2) the ecological footprint appears an increasing trend; (3) ecological pressure index rose to 0.91 from 0.44 during 1986-2002 on the Loess Plateau of northern Shaanxi with an increase of 47%; and (4) the ecological security in the study area is in a critical state, and the ecological oressure index has been increasing rapidlv. 展开更多
关键词 regional ecological security dynamic change spatial difference quantitative analysis the Loess Plateau in northern Shaanxi Province
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Temporal-spatial change and driving mechanism for regional difference of domestic tourism in China 被引量:1
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作者 Degen Wang Tian Chen 《Chinese Journal of Population,Resources and Environment》 2013年第1期69-78,共10页
By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism ... By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism in China from 1995 to 2009.According to the results,we drew the following conclusions:(1)The regional difference of domestic tourism in China tends to be narrowing generally,and is less than that of inbound tourism,playing an important role in narrowing the overall gap of regional tourism in China.(2)The regional internal difference features:inter-provincial difference in the eastern region and difference among the eastern,central and western regions are comparatively obvious and demonstrate a significantly shrinking tendency,the change tendency is consistent with the change tendency of overall difference and exercises a decisive role in overall difference,whereas the inter-provincial difference in the central and western regions is small and relatively stable,having less influence on the overall difference.(3)The temporal-spatial change in regional difference is featured by:low-level provinces occupy a majority and are concentrated in the central and western regions,showing a tendency of narrowing difference;high-level provinces are concentrated in the eastern region,showing a tendency of spreading to the central and western regions;spatial pattern of regional difference demonstrates 4 types,i.e."proliferation type","polarization type","quiescence type"and"collapse type."(4)The driving force for regional difference of domestic tourism in China comes down to 3 aspects:regional socio-economic attribute,regional transport accessibility level and regional development policy. 展开更多
关键词 DOMESTIC TOURISM regionAL DIFFERENCE temporal-spatial CHANGE driving mechanism China
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Impact of Climate Change on Urban Agglomerations in China’s Coastal Region
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作者 Dong Suocheng Tao Shu +4 位作者 YangWangzhou Li Fei LiShuangcheng Li Yu Liu Hongyan 《Chinese Journal of Population,Resources and Environment》 2012年第2期78-83,共6页
Climate change and urbanization issues are the two key factors that make humans liable to be affected by disasters, which are overlapped in urban agglomeration. The five big urban agglomerations of China with strong e... Climate change and urbanization issues are the two key factors that make humans liable to be affected by disasters, which are overlapped in urban agglomeration. The five big urban agglomerations of China with strong economic power are the important engines for national economic and social development. However, being in the sea-land mutual interaction belts with a vast hazard-bearing body, they are affected by sea-land compound disasters, and are liable to suffer heavy disaster losses with climate change. It is suggested that government departments concerned should fully recognize the impact of climate change on coastal urban agglomerations, propose strategies as soon as possible, and integrate the impact of climate change and adaptation countermeasures into the various kinds of social-economic development plans for coastal urban regions. 展开更多
关键词 climate change sea level rise urban agglomeration coastal region
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Quantifying Land Use Change in Zhejiang Coastal Region,China Using Multi-Temporal Landsat TM/ETM+Images 被引量:21
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作者 DING Han WANG Ren-Chao +3 位作者 WU Jia-Ping ZHOU Bin SHI Zhou DING Li-Xia 《Pedosphere》 SCIE CAS CSCD 2007年第6期712-720,共9页
Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images in 1985, 1986, 1993, 1994 and 2001 were used to quantify the land use and land cover changes (LUCC) in the Zhejiang coastal region wi... Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images in 1985, 1986, 1993, 1994 and 2001 were used to quantify the land use and land cover changes (LUCC) in the Zhejiang coastal region with a stratified unsupervised classification technique in conjunction with visual interpretation and to attempt an identification of the socioeconomic driving forces. In level I an overall accurate classification was achieved using a modified Anderson's Ⅰ/Ⅱ/Ⅲ-level classification scheme. The overall accuracy of the land use classification at Anderson level Ⅰ were 89.7% (1985), 91.6% (1993), and 90.4% (2001). The most rapid land use change was a dramatic increase in urban or built-up areas, which quadrupled from 1985 to 2001. Over 90% of this newly expanded built-up area was originally paddy fields or other croplands. In different parts of the Zhejiang coastal region, urban land expansion was spatially uneven. Temporally, land use development did not stabilized, and the two study periods of time (1985-1993 and 1993-2001) had different transition styles. Socioeconomic factors, such as gross domestic product, total population, and financial expenditure, were all highly correlated with the expansion of urban or built-up areas. Based on the degree of urban sprawl and socioeconomic factors, cities and towns were further divided into six subgroups, which may help decision makers improve land use for the region. 展开更多
关键词 coastal region driving factors land use change urban sprawl
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Changes in Typhoon Regional Heavy Precipitation Events over China from 1960 to 2018 被引量:2
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作者 Yangmei TIAN John LMCBRIDE +2 位作者 Fumin REN Guoping LI Tian FENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第2期272-283,共12页
In earlier studies,objective techniques have been used to determine the contribution of tropical cyclones to precipitation(TCP)in a region,where the Tropical cyclone Precipitation Event(TPE)and the Regional Heavy Prec... In earlier studies,objective techniques have been used to determine the contribution of tropical cyclones to precipitation(TCP)in a region,where the Tropical cyclone Precipitation Event(TPE)and the Regional Heavy Precipitation Events(RHPEs)are defined and investigated.In this study,TPE and RHPEs are combined to determine the Typhoon Regional Heavy Precipitation Events(TRHPEs),which is employed to evaluate the contribution of tropical cyclones to regional extreme precipitation events.Based on the Objective Identification Technique for Regional Extreme Events(OITREE)and the Objective Synoptic Analysis Technique(OSAT)to define TPE,temporal and spatial overlap indices are developed to identify the combined events as TRHPE.With daily precipitation data and TC best-track data over the western North Pacific from 1960 to 2018,86 TRHPEs have been identified.TRHPEs contribute as much as 20%of the RHPEs,but100%of events with extreme individual precipitation intensities.The major TRHPEs continued for approximately a week after tropical cyclone landfall,indicating a role of post landfall precipitation.The frequency and extreme intensity of TRHPEs display increasing trends,consistent with an observed positive trend in the mean intensity of TPEs as measured by the number of daily station precipitation observations exceeding 100 mm and 250 mm.More frequent landfalling Southeast and South China TCs induced more serious impacts in coastal areas in the Southeast and the South during 1990-2018 than1960-89.The roles of cyclone translation speed and"shifts"in cyclone tracks are examined as possible explanations for the temporal trends. 展开更多
关键词 TYPHOON regional heavy precipitation events changes temporal and spatial characteristics
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Study on Land Use Changes in the Yellow River Delta from 1980 to 2010
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作者 WANG Linlin ZHANG Tianning 《Journal of Landscape Research》 2015年第3期31-33,共3页
Taking the Yellow River Delta for example, this paper applied remote sensing and GIS to explore land use changes in the local area from 1980 to 2010. The results showed that arable land, and urban and rural constructi... Taking the Yellow River Delta for example, this paper applied remote sensing and GIS to explore land use changes in the local area from 1980 to 2010. The results showed that arable land, and urban and rural construction land were major land use types in the Yellow River Delta, unused land also took a large ratio; land use changes occurred mainly in coastal regions, in terms of change matrix, 25.46% of the grassland was reclaimed as arable land, unused land also witnessed great changes, specifi cally, 11.14% turned to arable land, 23.25% to construction land. This study provided references for the land use planning and development of the local area. 展开更多
关键词 the Yellow River Delta Land use change Change matrix coastal region
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Spatial-temporal Differentiation of Sauna Days with Different Intensities in China from 1961 to 2017
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作者 Feng KONG 《Agricultural Biotechnology》 CAS 2019年第6期75-82,共8页
Sauna weather with high temperature, high humidity and long standby time has become one of the main meteorological hazards faced by urban residents. Based on the daily maximum temperature and relative humidity dataset... Sauna weather with high temperature, high humidity and long standby time has become one of the main meteorological hazards faced by urban residents. Based on the daily maximum temperature and relative humidity datasets of 545 meteorological observation stations in China from 1961 to 2017, the spatial-temporal evolution characteristics of sauna days with different intensities in China were studied from three aspects: climatic state, trend and fluctuation characteristics, using the standard of sauna days defined by the Central Meteorological Observatory of China Meteorological Administration. The results showed that: firstly, the spatial pattern of sauna days with different intensities in China was high in southeast China and low in northwest China from 1961 to 2017, and the spatial pattern of sauna days with the same intensity in different research periods had little difference, which was in good agreement with the spatial pattern of sauna days with corresponding intensities in the whole research period. With the increase of intensity, the sauna days in China decreases gradually. Secondly, the trend of sauna days with different intensities in China was bounded by Hu Huanyong Line from 1961 to 2017, showing a pattern of increasing or decreasing mosaic in the southeast China and mainly decreasing trend, while the spatial differentiation pattern in the northwest China changed little. The trend of sauna days with different intensities in China increased significantly in 1991-2017 compared with 1961-1990. Thirdly, the fluctuation of sauna days with different intensities in China was bounded by Hu Huanyong Line, showing a spatial pattern of large fluctuations in the southeast China and small fluctuations in the northwest China. And the fluctuation of sauna days and heavy sauna days showed obvious threeblock distribution characteristics. The fluctuation characteristics of sauna days with different intensities in China from 1961 to 1990 and 1991 to 2017 were in good agreement with the whole research period. The fluctuation difference before and after 1990 mainly concentrated in the vicinity of Hu Huanyong Line and its southeast area, and the fluctuation differences increased mainly, indicating that the variation of sauna days with different intensities in the southeast China increased from 1991 to 2017. 展开更多
关键词 Sauna weather High temperature and heat waves spatial pattern interdecadal variation Climate change regional differentiation
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Extraction and Dynamic Spatial-Temporal Changes of Grassland Deterioration Research Hot Regions in China 被引量:4
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作者 胡云锋 韩月琪 +1 位作者 张云芝 庄园 《Journal of Resources and Ecology》 CSCD 2017年第4期352-358,共7页
The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matc... The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matching and other methods. The authors also construct a research hot regions extraction model of grassland deterioration in China based on a comprehensive research hot regions index of toponyms and then analyze the spatial pattern and dynamic change in research hot regions of grassland deterioration in China. The research shows the following:(1) The spatial heterogeneity of grassland deterioration in China can be effectively described by a model of grassland deterioration based on the comprehensive research hot regions index.(2) The research hot regions of grassland deterioration are mainly distributed in most regions of Inner Mongolia, Xinjiang, Qinghai, Tibet, Gansu and other provinces. The northeastern region of Inner Mongolia(such as Hulunbeier) and the eastern region of Inner Mongolia(such as Xilin Gol, Chifeng and Wulanchabu) are significant hot regions in the study of grassland deterioration.(3) The number of high research hot regions increases from 81 in the 1950 s to 99 in the 2000s; the area increases from 1.038 million km2 to 1.146 million km2. The degree of hot for grassland deterioration research in 197 counties showed an upward trend. This paper also discusses the relationship between the region of research hot regions and the region of grassland deterioration and then indicates the differences between them in time matching, space matching and concept matching. 展开更多
关键词 knowledge engine hot regions analysis grassland deterioration region extraction spatial distribution dynamic change
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Dynamic change of desertified land in each county around Qinghai Lake in recent 30 years
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作者 TIAN Li-hui ZHANG Deng-shan +3 位作者 HU Meng-jun LU Rui-jie ZHAO Chao WU Wang-yang 《地球环境学报》 2012年第6期1134-1143,共10页
Desertification is one of the most serious eco-environmental problems around Qinghai Lake.Based on GIS and RS,GIS analysis was used to obtain the information of spatial-temporal change and different pattern of deserti... Desertification is one of the most serious eco-environmental problems around Qinghai Lake.Based on GIS and RS,GIS analysis was used to obtain the information of spatial-temporal change and different pattern of desertification in each county around Qinghai Lake in four phases of1976,1987,1995 and 2006.Using the function of intersect and overlay supported by ARCGIS,with analyzing attributes of vector RS images,we obtained transition data and established transfer matrix of land-use types in recent 30 years,besides,protracted land-use transition maps of all desertification classes.In further,we analyzed transition quantity and direction of desertification in each county,moreover,reconstructed the process of spatial-temporal evolution of desertification.The results are showed below:(1)it's the transition between desertified land and others but not in the desertified that played the main role in Gangcha and Gonghe County,while the transfer between desertified lands were greater than that with other land-use types in Haiyan County.(2)Extremely severe desertified land mainly distributes in Ketu and Sand Islands that belongs to Haiyan County,and moderate desertified land in riversides of Gangcha County,also,the light desertification expanded too rapidly to become the most desertified land-use type in the surrounding of Qinghai Lake since 1976.(3)By using relative change rate of desertified land,the regional variability rank from top to toe was Gangcha,Haiyan and Gonghe. 展开更多
关键词 the area around Qinghai Lake desertified land transition of land-use types spatial change regional variation
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Changes in the spatial scale of Beijing UHI and urban development 被引量:5
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作者 YU Shuqiu, BIAN Lingen & LIN Xuechun State Key Laboratory on Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China National Climate Center, China Meteorological Administration, Beijing 100081, China 《Science China Earth Sciences》 SCIE EI CAS 2005年第z2期116-127,共12页
The seasonal and interannual variations of Beijing urban heat island (UHI) are investigated in this paper using the temperature data from 1960 to 2000 at 20 meteorological stations in the Beijing region, and then the ... The seasonal and interannual variations of Beijing urban heat island (UHI) are investigated in this paper using the temperature data from 1960 to 2000 at 20 meteorological stations in the Beijing region, and then the relationship between the intensity and spatial scale of UHI and Beijing urbanization indices is analyzed and discussed. Main conclusions are the followings. First, Beijing UHI shows obvious seasonal variations, and it is strongest in winter, next in spring and autumn, and least in summer. The seasonal variation of the UHI mainly occurs in the urban area. The UHI intensity at the center of Beijing is more than 0.8℃ in winter, and only 0.5℃ in summer. Second, the intensity of Beijing HUI exhibits a clear interannual warming trend with its mean growth rate (MGR) being 0.3088℃/10 a. The MGR of HUI is largest in winter, next in spring and autumn, and least in summer, and the urban temperature increase makes a major contribution to the growth of HUI intensity. Third, since the Reform and Opening, the urbanization indices have grown several ten times or even one hundred times, the intensity of HUI has increased dramatically, and its spatial scale also expanded distinctively along with the expansion of urban architectural complexes. Fourth, the interannual variation of urbanization indices is very similar with that of HUI intensity, and their linear correlation coefficients are significant at a more than 0.001 confidence level. 展开更多
关键词 BEIJinG region temperature change heat ISLAND effect HUI spatial scale human activities.
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The effect of environmental factors on spatial variability in land use change in the high-sediment region of China's Loess Plateau 被引量:6
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作者 LUO Ya YANG Shengtian +5 位作者 ZHAO Changsen LIU Xiaoyan LIU Changming WU Linna ZHAQ Haigen ZHANG Yichi 《Journal of Geographical Sciences》 SCIE CSCD 2014年第5期802-814,共13页
In areas with topographic heterogeneity, land use change is spatially variable and influenced by climate, soil properties, and topography. To better understand this variability in the high-sediment region of the Loess... In areas with topographic heterogeneity, land use change is spatially variable and influenced by climate, soil properties, and topography. To better understand this variability in the high-sediment region of the Loess Plateau in which soil loss is most severe and sediment diameter is larger than in other regions of the plateau, this study builds some indicators to identify the characteristics of land use change and then analyze the spatial variability as it is affected by climate, soil property, and topography. We build two indicators, a land use change intensity index and a vegetation change index, to characterize the intensity of land use change, and the degree of vegetation restoration, respectively. Based on a subsection mean method, the two indicators are then used to assess the spatial variability of land use change affected by climatic, edaphic, and topographic elements. The results indicate that: 1) Land use changed significantly in the period 1998-2010. The total area experiencing land use change was 42,302 km2, accounting for 22.57%of the study area. High-coverage grassland, other woodland, and forest increased significantly, while low-coverage grassland and farmland decreased in 2010 compared with 1998.2) Land use change occurred primarily west of the Yellow River, between 35 and 38 degrees north latitude. The four transformation types, including (a) low-coverage grassland to medium-coverage grassland, (b) medium-coverage grassland to high-coverage grassland, (c) farmland to other woodland, and (d) farmland to medium-coverage grassland, were the primary types of land use change, together constituting 60% of the area experiencing land use change. 3) The spatial variability of land use change was significantly affected by properties of dryness/wetness, soil conditions and slope gradient. In general, land use changed dramatically in semi-arid regions, remained relatively stable in arid regions, changed significantly in clay-rich soil, remained relatively stable in clay-poor soil, changed dramatically in steeper slopes, and remained relatively stable in tablelands and low-lying regions. The increase in vegetation coincided with increasing changes in land use for each physical element. These findings allow for an evaluation of the effect of the Grain to Green Program, and are applicable to the design of soil and water conservation projects on the Loess Plateau of China. 展开更多
关键词 spatial variability land use change dryness/wetness soil properties slope gradient the high-sedi-ment region of China's Loess Plateau
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Spatial and temporal distribution of Neolithic sites in coastal China:Sea level changes, geomorphic evolution and human adaption 被引量:9
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作者 ZHENG HongBo ZHOU YouSheng +10 位作者 YANG Qing HU ZhuJun LING GuangJiu ZHANG JuZhong GU ChunGuang WANG YingYing CAO YeTing HUANG XianRong CHENG Yue ZHANG XiaoYu WU WenXiang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第2期123-133,共11页
The East China coastal plain is one of the most important Neolithic culture areas in China, where rich archaeological sites including those producing the earliest domesticated rice are observed. It is also a place whe... The East China coastal plain is one of the most important Neolithic culture areas in China, where rich archaeological sites including those producing the earliest domesticated rice are observed. It is also a place where landscape has experienced dramatic evolution during the Holocene when both sea level and climate changed, such that it is an ideal place for studying human-environment interaction. This study investigated over 2000 sites of pre-history and Shang and Zhou Dynasties, with 655 of which being Neolithic ages, by using DEM and GIS methods. The results suggest that the spatial and temporal distribution of Neolithic sites has largely been controlled by landscape evolution(particularly changes in coastal line), which ultimately governed by sea level changes. During early Holocene, Neolithic sites sparsely distributed in the intermountain basins of east Zhejiang Province, far from the influence of ocean. Over the period of 9–7 ka, the coastal plain(including the shelf) was largely submerged,only the feet of low hills to the south and southwest of the study area, and islands protruding the estuary, cradled limited number of settlements with characteristic "maritime components". At about 7 ka, sea level rise decelerated prominently, while sediments supply in the drainage remained high value, the combination of which led to land formation and propagation. Vast space during this period facilitated the growth of settlements in both size and number. In the mean time, however, the coastal plain was vulnerable to extreme environmental events such as storms and flooding owning to its geomorphic nature, which exerted great influence on the rise and fall of Neolithic culture. 展开更多
关键词 East China coastal plain NEOLITHIC spatial and temporal distribution of Neolithic sites Sea level change Geomorphic evolution
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Spatial function regionalization and governance of coastal zone: A case study in Ningbo City 被引量:3
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作者 孙伟 陈诚 王磊 《Journal of Geographical Sciences》 SCIE CSCD 2018年第8期1167-1181,共15页
Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources,playing a... Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources,playing an important role in regional sustainable development.Depending on the natural,economic,and societal characteristics of a region,research topics such as using relevant methods to divide the coastline,proper spatial development of the coast,protecting coastal zones,and achieving higher spatial resource distribution efficiency have recently become hot topics in geographic research.Most of the scholars construct the evaluation index system from the perspective of economic and ecological factors and undertake some exploration of the division methods.However,the selection of indicators for a coastal zone needs a different and more scientific approach.There is a need for emphasizing the overall strategy of land-ocean integration in developing spatial resources in a coastal zone.Taking the coastal zone in Ningbo as an example,this paper develops a new evaluation framework and spatial function regionalization method that is used to divide the coastline and coastal zone.Based on the perspective of overall strategy for the land and ocean,we evaluate the suitability of coastline development.We then propose the spatial function regionalization of the coastal zone.Finally,based on the status quo of spatial development in Ningbo,we divide the coastal zone into ecological space,production space and living space,and propose adjustment directions and control requirements for the different types of spatial layouts. 展开更多
关键词 coastal zone COASTLinE spatial function regionalization spatial governance Ningbo City
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Response of water budget to recent climatic changes in the source region of the Yellow River 被引量:17
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作者 ZHOU DeGang HUANG RongHui 《Chinese Science Bulletin》 SCIE CAS 2012年第17期2155-2162,共8页
Discharge in the source region of the Yellow River significantly declined after 1990.China Meteorological Administration(CMA) data show that precipitation in this region was low in the 1990s but returned to above norm... Discharge in the source region of the Yellow River significantly declined after 1990.China Meteorological Administration(CMA) data show that precipitation in this region was low in the 1990s but returned to above normal after 2002;in recent decades there has been rapid warming of surface air,moistening and wind speed decrease.To investigate the influences of recent climatic changes on the water budget,this study simulates the surface water budget at CMA stations within and surrounding the source region during 1960-2006,using an improved land surface model.Results indicate that the spatial pattern of precipitation change is an important factor(except for precipitation amount and intensity) in determining the response of runoff to precipitation changes.Low runoff in the 1990s was consistent with precipitation amount and intensity.The recovery of precipitation after 2002 is mainly from increased precipitation in the dry area of the source region.Evaporation was mainly limited by water availability in this dry area,and thus most of the precipitation increase was evaporated.By contrast,energy availability was a more important influence on evaporation in the wet area.There was more evaporation in the wet area because of rapid warming,although precipitation amount partly decreased and partly increased,contributing to the reduction of runoff after 2002.This control on evaporation and its response,together with the modified spatial pattern of precipitation,produced a water budget unfavorable for runoff generation in the source region during recent years. 展开更多
关键词 黄河源头地区 降水量 气候变化 预算 中国气象局 空间格局 降水径流 蒸发量
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EOF分析在海岸地貌与沉积学研究中的应用进展 被引量:19
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作者 夏非 张永战 吴蔚 《地理科学进展》 CSCD 北大核心 2009年第2期174-186,共13页
海岸地貌形成演化的过程和机制是当今海岸地貌与沉积学研究的核心任务。但是,对于海岸带这样高维数非线性系统行为的认识与研究还很有限,因而预测海岸地区地貌演变与沉积物输运就变得比较困难,尤其是动力数值模型在较大时空尺度上的模... 海岸地貌形成演化的过程和机制是当今海岸地貌与沉积学研究的核心任务。但是,对于海岸带这样高维数非线性系统行为的认识与研究还很有限,因而预测海岸地区地貌演变与沉积物输运就变得比较困难,尤其是动力数值模型在较大时空尺度上的模拟并不理想。数据驱动模型可以一定程度上解决这一问题,并且在数据驱动模型构建之前,经验正交函数(EOF)分析技术能够有效提取、定量表达数据中的主要型式与它们的时空演变,以及不同型式之间是如何相互联系的。这不但有助于构建数据驱动模型进行模拟,更有益于理解这些主控因素是如何影响海岸地貌演化的,进而不断丰富对于海岸地貌演化的过程与机制的认识。故本文在系统整理大量国内外文献的基础上,首先简要介绍了EOF分析的基本原理,然后从砂质和淤泥质海岸剖面的时空变化特征、河口近岸海底冲淤变化的时空演变特征和预测、海岸海洋地区沉积物粒度分布特征和输运等几个方面综述EOF分析在这些研究中的应用进展,同时比较分析研究实例中的问题,进而分析当前研究中的不足,提出应该主要从提高海岸地貌与沉积数据的野外获取手段与时空分辨率,拓宽可供EOF分析的时间或非时间序列的数据类型;深入挖掘EOF分析结果所显示出的海岸地貌与沉积现象中的物理过程与机制,以期为特定时空尺度的海岸地貌与沉积数值模拟提供有价值的参考信息;多与其他线性或非线性分析技术联合使用以作深入分析解释或模拟这三方面来做进一步改进,为实现EOF分析在海岸地貌与沉积学研究中的深入应用与发展提供借鉴。 展开更多
关键词 Eof分析 海岸地貌与沉积学 时空变化特征 过程和机制 海岸地貌演变预测
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基于Google Earth Engine平台的关中冬小麦面积时空变化监测 被引量:8
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作者 郭新 王乃江 +3 位作者 张玲玲 郭永强 褚晓升 冯浩 《干旱地区农业研究》 CSCD 北大核心 2020年第3期275-280,共6页
以关中地区为研究区,基于Google Earth Engine(GEE)平台,根据冬小麦生育期内归一化植被指数(NDVI)时序曲线和物候特征,采用NDVI重构增幅算法和光谱突变斜率,构建了关中地区冬小麦提取模型并实现了冬小麦种植面积的提取。用农业统计面积... 以关中地区为研究区,基于Google Earth Engine(GEE)平台,根据冬小麦生育期内归一化植被指数(NDVI)时序曲线和物候特征,采用NDVI重构增幅算法和光谱突变斜率,构建了关中地区冬小麦提取模型并实现了冬小麦种植面积的提取。用农业统计面积验证提取结果表明:在市级和县级尺度上,决定系数R2分别为0.82和0.62,一致性指标d分别为0.95和0.84,提取结果与实地调查数据的空间一致性精度为93.4%。结果显示:关中地区冬小麦主要分布在中部关中平原,冬小麦种植面积在2011—2017年呈下降趋势,减少了83.22×10^3 hm^2(8.47%)。综合考虑冬小麦NDVI时序曲线的“峰”“谷”特征,具有一定的普适性,可为大面积连续年份冬小麦种植面积时空监测提供参考。 展开更多
关键词 遥感 冬小麦种植面积 时空变化 MODIS NDVI Google Earth Engine 关中地区
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