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Urban Geography and the Production of Socio-Environmental Inequalities
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作者 Marc Parés 《International Journal of Geosciences》 2013年第6期44-52,共9页
In this article we use the Urban Political Ecology approach to show that by analysing governance networks we can better understand the production of certain socio-environmental transformations that negatively affect s... In this article we use the Urban Political Ecology approach to show that by analysing governance networks we can better understand the production of certain socio-environmental transformations that negatively affect some social groups while benefiting others. Drawing upon two case studies in the UK, the article explores the dialectical relationships between different modes of urban governance on one hand and the socio-environmental transformations fulfilled in each case study on the other hand. The article concludes that although urban regeneration policies are always constrained by the neoliberal established framework of power relations, policy outputs and outcomes could be very different from one place to another, shaping uneven socio-environmental constructions. Finally, we make some recommendations in order to stimulate the production of more sustainable communities in the future. 展开更多
关键词 URBAN Regeneration GOVERNANCE URBAN POLITICAL Ecology ENVIRONMENTAL JUSTICE Sustainable Communities
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Spatiotemporal Dynamics of Internal Migration in Burkina Faso
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作者 Gansaonré Raogo Noël Dahani Dramane 《Journal of Environmental & Earth Sciences》 2025年第2期31-48,共18页
Migration is a complex demographic phenomenon.Its dynamics can be explained by several factors whose spatial and temporal evolution is not easy to control.That is why this article aims to understand the factors of mig... Migration is a complex demographic phenomenon.Its dynamics can be explained by several factors whose spatial and temporal evolution is not easy to control.That is why this article aims to understand the factors of migration from a spatiotemporal perspective to fill the gaps in the literature.The aim of this article is to analyse the spatiotemporal dynamics of internal migration factors to deduce the zones of origin and destination in Burkina Faso.To do this,several types of data were used.These included secondary,spatial,statistical and survey data.The results of this study show that the influence of internal migration factors is uneven.The spatial distribution of internal migration factors follows a north-south gradient,with favourable conditions in the south.In fact,the northern part is characterised by a large population exodus,with around 42.6%of outgoing internal migrants,and the southern part by a large population influx.This southern part of the country receives around 34.6%of internal migrants.The areas from which migrants depart have unfavourable climatic,environmental,or socio-economic conditions,whereas the areas to which migrants migrate are characterised by favourable conditions for these factors. 展开更多
关键词 Burkina Faso Internal Migration FACTOR GIS Multi-Criteria Analysis
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Groundwater resources exploitation management in response to water scarcity challenges in Khuzestan Province,Iran
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作者 Marsa Bahiraie Seiyed Mossa Hosseini Bahareh Hossein-Panahi 《Journal of Groundwater Science and Engineering》 2025年第3期268-285,共18页
Water scarcity in Khuzestan Province,Iran,has attracted growing concerns despite the region's abundant water resources.The province predominantly relies on surface water,prompting an assessment of groundwater'... Water scarcity in Khuzestan Province,Iran,has attracted growing concerns despite the region's abundant water resources.The province predominantly relies on surface water,prompting an assessment of groundwater's potential to supplement water supplies during surface water shortages.This study assesses the province's groundwater availability and quality under increased exploitation conditions.Between 2008 and 2018,data on groundwater quantity and quality were collected from 204 exploration wells and 70 piezometric wells across 19 aquifers.The analysis revealed that 53%of aquifers in the eastern and northeastern regions experienced declining groundwater levels.Hydrochemical assessments indicated low concentrations of major ions in the northeastern,while high levels were observed from the central region towards the southeast.These variations were attributed to agricultural and industrial activities,seawater intrusion,and the influences of evaporation and geological factors.The dominant hydrochemical facies identified were of the Ca-Cl type.Water quality classification showed that 48%of groundwater samples fell within the C4S4-C4S1 category,primarily in the western,central,and southern regions,while 27%were classified as C3S2,C3S1,and 25%as C2S1,mainly in the northern and eastern regions.The Irrigation WWater Quality(IWQ)index indicated that many samples were suitable for irrigation.Additionally,the analysis potable groundwater was primarily found in the northern,northeastern,and eastern aquifers,with quality declining toward the south.The study highlights that certain aquifers in the northern and eastern regions offer greater potential for sustainable groundwater exploitation during water shortages.These findings provide valuable insights for on how to implement effective land and water management strategies to mitigate future water crises. 展开更多
关键词 Groundwater level Groundwater quantity Hydro-geochemistry Irrigation water Drinking water Khuzestan province GIS-based maps
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The first exception:the obelisk in memory of Napoleonic prisoners on the island of Cabrera(1847,Spain)
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作者 Alberto Cañas de Pablos 《Built Heritage》 2025年第3期22-31,共10页
Wars have been frequently commemorated in public space.In Spain,the Peninsular War has become key for memory policies almost since its beginning.More than 370 monuments from that period still stand today.Most of these... Wars have been frequently commemorated in public space.In Spain,the Peninsular War has become key for memory policies almost since its beginning.More than 370 monuments from that period still stand today.Most of these monuments recall heroic achievements by Spanish men or regiments,but some(more than twenty)provide reminders of the occupying troops coming from France.The most important of these is the obelisk built in Cabrera,in the Balearic archipelago,where many prisoners,who had been defeated in Bailén(1808),were taken.Many of those soldiers died and/or suffered several illnesses there,prompting the Prince of Joinville to commission a monument there in their memory.Although there Swiss,German,Polish and Italian soldiers were also present,only the French are engraved in the stone.Primary and secondary sources have been used to complete this research.Despite the difficult place of the monument and the limited number of recent studies,this paper studies and analyses the process that led to this memory antenna. 展开更多
关键词 Peninsular War Public history Island of Cabrera MONUMENTS MEMORY
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Prediction and Modelling of Land Use Change in Pesawaran District Lampung Using ANN and Cellular Automata
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作者 Irma Lusi Nugraheni Mustofa Usman Sutarto Sutarto 《Journal of Environmental & Earth Sciences》 2025年第6期46-62,共17页
The simultaneous increase in development in Pesawaran Regency is closely correlated with the intense competi-tion for land use.However,low policy implementation effectiveness has led to construction beyond designated ... The simultaneous increase in development in Pesawaran Regency is closely correlated with the intense competi-tion for land use.However,low policy implementation effectiveness has led to construction beyond designated spatial plan.The study used a quantitative survey using Landsat images in 2016,2019,and 2022.The data analysis techniques used geographic information systems integrated with Artificial Neural Network(ANN)and Cellular Automata(CA)models.This study aims to predict land-use change in 2031,evaluate its alignment with spatial planning,and provide guidance for controlling land-use change.The results showed that there has been an increase in land use.In 2019,built-up land reached 7,069.65 Ha.The model shows its ability to predict land simulation and transformation,where it is predicted that built-up land in 2031 will experience an increase of up to 40.10%,so development and change cannot be avoided every year.This study also suggests that decision-makers and local governments should reconsider spatial planning strategies.This study shows that there have been many land use changes from 2016 to 2022.The model shows its ability to predict simulation and land transformation.When using the model,there are many changes in the land use area in 2031.This is due to wet agricultural land turning into built-up land by almost 70%.This study shows that road network influence land-use change.The cellular automata model managed to capture the complexity with simple rules.Predictions for future research should focus on conserving wetlands and primary forests. 展开更多
关键词 Land Use Model System Information Geography Cellular Automata Artificial Neural Network(ANN)
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广东省水稻生物质能的估算 被引量:23
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作者 张晓浩 黎夏 +1 位作者 施迅 刘凯 《遥感信息》 CSCD 2007年第1期26-29,21,I0003,共6页
利用MODIS传感器的MOD17A3数据,通过处理获取了广东省的NPP(植被净初级生产力)分布图;同时,根据Landsat获取的广东省土地利用类型图,提取出广东省水稻的空间分布图。将两者叠加并进行相关运算和分析,得到全省水稻生物量的分布图及其统... 利用MODIS传感器的MOD17A3数据,通过处理获取了广东省的NPP(植被净初级生产力)分布图;同时,根据Landsat获取的广东省土地利用类型图,提取出广东省水稻的空间分布图。将两者叠加并进行相关运算和分析,得到全省水稻生物量的分布图及其统计数据。同时,进行野外测量并参考已有的研究成果,取稻草和稻秆产量与水稻产量的重量比为0.623,获得水稻总的农作物残余。除去还田、造纸及用做牲畜饲料的那部分,仍有三成左右的可用生物量。研究表明:珠江三角洲经济发展迅猛的城市,水稻生物质能的占有量较少;而在一些边远山区,水稻生物质能占的比重明显偏大。本文通过定量化的研究,为以后广东省水稻生物质能的开发提供了有价值的参考信息。 展开更多
关键词 MOD17A3 可用生物量 水稻 生物质能
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信息设备产业经济发展的建模研究--基于学术属性与技术属性
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作者 张杰敏 路方达 《经济管理学刊(中英文版)》 2016年第2期57-63,共7页
信息设备产业是知识密集型和技术密集型的产业,产业发展的核心推动力是自主创新能力。本文研究信息设备产业经济发展的建模问题,将学术性属性和技术性属性引入模型,创立了涵盖创新指数、资产转化指数和生产力指数的指标模型,定义了... 信息设备产业是知识密集型和技术密集型的产业,产业发展的核心推动力是自主创新能力。本文研究信息设备产业经济发展的建模问题,将学术性属性和技术性属性引入模型,创立了涵盖创新指数、资产转化指数和生产力指数的指标模型,定义了信息设备产业模型的理论密度、技术密度和新产品密度及其计算方式;确立了特定研究问题上下文相关的属性权重的计算方法;针对所建立的信息设备产业模型,对2010年至2014年批量数据进行了分析,并通过Python程序实现了多属性决策的排序和择优,以可视化图形方式展示了部分数据分析结果。 展开更多
关键词 理论密度 技术密度 新产品密度 信息设备产业模型
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Assessing Vulnerability to Drought Based on Exposure,Sensitivity and Adaptive Capacity:A Case Study in Middle Inner Mongolia of China 被引量:20
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作者 LIU Xiaoqian WANG Yanglin +2 位作者 PENG Jian Ademola K BRAIMOH YIN He 《Chinese Geographical Science》 SCIE CSCD 2013年第1期13-25,共13页
In this paper,we proposed a framework for evaluating the performance of ecosystem strategies prepared for enhancing vulnerability reduction in the face of hazards due to climate change.The framework highlights the pos... In this paper,we proposed a framework for evaluating the performance of ecosystem strategies prepared for enhancing vulnerability reduction in the face of hazards due to climate change.The framework highlights the positive effects of human activities in the coupled human and natural system(CHANS) by introducing adaptive capacity as an evaluation criterion.A built-in regional vulnerability to a certain hazard was generated based upon interaction of three dimensions of vulnerability:exposure,sensitivity and adaptive capacity.We illustrated the application of this framework in the temperate farming-grazing transitional zone in the middle Inner Mongolia of the northern China,where drought hazard is the key threat to the CHANS.Specific indices were produced to translate such climate variance and social-economic differences into specific indicators.The results showed that the most exposed regions are the inner land areas,while counties located in the eastern part are potentially the most adaptive ones.Ordos City and Bayannur City are most frequently influenced by multiple climate variances,showing highest sensitivity.Analysis also indicated that differences in the ability to adapt to changes are the main causes of spatial differences.After depiction of the spatial differentiations and analysis of the reasons,climate zones were divided to depict the differences in facing to the drought threats.The climate zones were shown to be similar to vulnerability zones based on the quantitative structure of indexes drafted by a triangular map.Further analysis of the composition of the vulnerability index showed that the evaluation criteria were effective in validating the spatial differentiation but potentially ineffective because of their limited time scope.This research will be a demonstration of how to combine the three dimensions by quantitative methods and will thus provide a guide for government to vulnerability reduction management. 展开更多
关键词 vulnerability assessment standardized precipitation index (SPI) EXPOSURE sensitivity adaptive capacity
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Millennial-centennial Scales Climate Changes of Holocene Indicated by Magnetic Susceptibility of High-resolution Section in Salawusu River Valley, China 被引量:21
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作者 LU Yingxia LI Baosheng +4 位作者 WEN Xiaohao QIU Shifan WANG Fengnian NIU Dongfeng LI Zhiwen 《Chinese Geographical Science》 SCIE CSCD 2010年第3期243-251,共9页
The upmost segment (Holocene series) of the Milanggouwan stratigraphic section (MGS 1) in the Salawusu River valley shows 11 sedimentary cycles of dune sands and fluvio-lacustrine facies, or dune sands and paleoso... The upmost segment (Holocene series) of the Milanggouwan stratigraphic section (MGS 1) in the Salawusu River valley shows 11 sedimentary cycles of dune sands and fluvio-lacustrine facies, or dune sands and paleosols. The analysis of the magnetic susceptibility of this segment suggests that there are 11 magnetic susceptibility cycles with the value alternating from low to high, in which the layers of the dune sands correspond to the lower value of the magnetic susceptibility and the layers of fluvio-lacustrine facies and paleosols correspond to the higher peaks. The study reveals that the low and high magnetic susceptibility values indicate the climate dominated by cold-arid winter monsoon and warm-humid summer monsoon of East Asia, respectively, and the study area has experienced at least 22 times of milleunial-centennial scales climate alternation from the cold-arid to the warm-humid during the Holocene. In terms of the time and the climate nature, the variations basically correspond to those of the North Atlantic and some records of cold-warm changes in China as well. They might be caused by the alternation of winter and summer monsoons in the Mu Us Desert induced by global climate fluctuations in the Holocene. 展开更多
关键词 MGS1 segment magnetic susceptibility millennial-centennial scales climate changes HOLOCENE Salawusu River valley
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USERS′ PERCEPTION OF KOWLOON PARK, HONG KONG:VISITING PATTERNS AND SCENIC ASPECTS 被引量:6
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作者 WONG Koon-kwai Manfred DOMROES 《Chinese Geographical Science》 SCIE CSCD 2004年第3期269-275,共7页
Hong Kong is a hyper-dense city with 7x10(6) people living in an area of 1100km(2). One way to improve the livability of compacted and congested cities like Hong Kong is through the provision of urban parks, an aspect... Hong Kong is a hyper-dense city with 7x10(6) people living in an area of 1100km(2). One way to improve the livability of compacted and congested cities like Hong Kong is through the provision of urban parks, an aspect that has largely been under-researched. This study focuses on how users perceive and utilize various facilities in the Kowloon Park. The findings revealed that the Kowloon Park is one of the most preferred parks in Hong Kong for both local residents and tourists. Users were quite satisfied with the park's facilities. Notably, the most important component of an urban park is its greenery. This is followed by water elements, seating places, and facilities for various recreational activities. The improvements users would like to see in urban parks include good design and management, meeting users' needs, overcoming barriers to use, and providing a high quality and varied experience for different groups in the community. The findings of this study provide a good basis to address park management issues from the users' perspective. In particular, parks should provide easy access, encourage optimum usage and enable complimentary improvements to the environment. 展开更多
关键词 urban park visiting pattern user perception urban park management
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Geomorphic features of Quaternary glaciation in the Taniantaweng Mountain, on the southeastern Qinghai-Tibet Plateau 被引量:5
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作者 ZHANG Wei CHAI Le +5 位作者 IAN S.Evans LIU Liang LI Ya-peng QIAO Jing-ru TANG Qian-yu SUN Bo 《Journal of Mountain Science》 SCIE CSCD 2019年第2期256-274,共19页
We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yun... We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yunnan-Guizhou Plateau. To reconstruct the history of glacial evolution during the Quaternary Glaciation, we present a ~13000 km^2 geomorphologic map(1:440,000) for the Quaternary glaciations, as well as three electron spin resonance(ESR) ages and three optically stimulated luminescence(OSL) ages from the landforms. By integrating these with ages from previous studies, four major glacial advances are identified during marine oxygen isotope stages(MIS) 6, 3, 2 and 1. This glacial chronology is in reasonable agreement with existing glacial chronologies from other parts of the Hengduan Mountains and surrounding mountains. Glaciers had extended to the Yuqu River during the glacial maximum advance(MIS 6), but became successively more restricted from MIS 3 to MIS 1. The glacial distribution show that precipitation brought by the south Asian monsoon might play a primary role in driving glacial advances during the last glacial period in the southeastern Qinghai-Tibet Plateau. 展开更多
关键词 Qinghai-Tibet Plateau Taniantaweng MOUNTAIN GLACIAL LANDFORM ESR DATING OSL DATING South Asian monsoon
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Spatial and temporal variations of vegetation in Qinghai Province based on satellite data 被引量:9
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作者 WANG Liwen WEI Yaxing NIU Zheng 《Journal of Geographical Sciences》 SCIE CSCD 2008年第1期73-84,共12页
This paper used five years (2001-2006) time series of MODIS NDVI images with a 1-km spatial resolution to produce a land cover map of Qinghai Province in China. A classification approach for different land cover typ... This paper used five years (2001-2006) time series of MODIS NDVI images with a 1-km spatial resolution to produce a land cover map of Qinghai Province in China. A classification approach for different land cover types with special emphasis on vegetation, especially on sparse vegetation, was developed which synthesized Decision Tree Classification, Supervised Classification and Unsupervised Classification. The spatial distribution and dynamic change of vegetation cover in Qinghai from 2001 to 2006 were analyzed based on the land cover classification map and five grade elevation belts derived from Qinghai DEM. The result shows that vegetation cover in Qinghai in recent five years has been some improved and the area of vegetation was increased from 370,047 km^2 in 2001 to 374,576 km^2 in 2006. Meanwhile, vegetation cover ratio was increased by 0.63%. Vegetation cover ratio in high mountain belt is the largest (67.92%) among the five grade elevation belts in Qinghai Province. The second largest vegetation cover ratio is in middle mountain belt (61.80%). Next, in the order of the decreasing vegetation cover ratio, the remaining grades are extreme high mountain belt (38.98%), low mountain belt (25.55%) and flat region belt (15.46%). The area of middle density grassland in high mountain belt is the biggest (94,003 km^2), and vegetation cover ratio of dense grassland in middle mountain belt is the highest (32.62%), and the increased area of dense grassland in high mountain belt is the greatest (1280 km^2). In recent five years the conversion from sparse grass to middle density grass in high mountain belt has been the largest vegetation cover variation and the converted area is 15931 km^2. 展开更多
关键词 QINGHAI VEGETATION MODIS NDVI DEM spatial distribution
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2003年南极威德尔海至普里兹湾之间海冰分布研究(英文) 被引量:6
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作者 唐述林 李志军 +1 位作者 康建成 周尚哲 《冰川冻土》 CSCD 北大核心 2004年第2期142-145,共4页
Ship-based sea ice observation data (concentrations, ice thickness, topography and overlying snow cover) were collected from Middle Weddell Sea to Prydz Bay, Antarctic during the period of 4 to 17 Jan 2003. Antarctic ... Ship-based sea ice observation data (concentrations, ice thickness, topography and overlying snow cover) were collected from Middle Weddell Sea to Prydz Bay, Antarctic during the period of 4 to 17 Jan 2003. Antarctic ice chart of first week of Jan 2003 was derived from National Ice Center (NIC). The compared analysis of sea ice concentrations and thickness distributions were conducted though in situ data and NIC chart. Results from sea ice concentration-analysis indicated the presence of large-scale open water between 2000 and 4100 km along transit route resulted from sea ice drifting. We describe the existence of mostly smooth first-year sea ice in study region ranged between 30 and 120 cm. We also display the derived overlying snow coverage. Our results reveal the strong correspondence between ship-based observations and remotely sensed ice charts whatever in ice concentrations and ice thickness distributions. 展开更多
关键词 海冰 南极 威德尔海 普里兹湾
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Assessing the USLE Crop and Management Factor C for Soil Erosion Modeling in a Large Mountainous Watershed in Central China 被引量:12
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作者 Sarah Schnbrodt Patrick Saumer +2 位作者 Thorsten Behrens Christoph Seeber Thomas Scholten 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期835-845,共11页
Due to the impoundment of the Yangtze River, the Three Gorges Dam in China fosters high land-use dynamics. Soil erosion is expected to increase dramatically. One of the key factors in soil erosion control is the veget... Due to the impoundment of the Yangtze River, the Three Gorges Dam in China fosters high land-use dynamics. Soil erosion is expected to increase dramatically. One of the key factors in soil erosion control is the vegetation cover and crop type. However, determining these factors adequately for the use in soil erosion modeling is very time-consuming especially for large mountainous areas, such as the Xiangxi (香溪) catchment in the Three Gorges area. In our study, the crop and management factor C was calculated using the fractional vegetation cover (CFvc) based on Landsat-TM images from 2005, 2006, and 2007 and on literature studies (CLIT). In 2007, the values of CFvc range between 0.001 and 0.98 in the Xiangxi catchment. The mean CFVC value is 0.05. CLIT values are distinctly higher, ranging from 0.08 to 0.46 with a mean value of 0.32 in the Xiangxi catchment. The mean potential soil loss amounts to 120.62 t/ha/a in the Xiangxi catchment when using CLIT for modeling. Based on CFVC, the predicted mean soil loss in the Xiangxi catchment is 11.50 t/ha/a. Therefore, CLIT appears to bemore reliable than the C factor based on the fractional vegetation cover. 展开更多
关键词 C factor soil erosion modeling Universal Soil Loss Equation fractional vegetation cover Three Gorges Dam Yangtze River.
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Numerical Simulation of the Impact of Vegetation Index on the Interannual Variation of Summer Precipitation in the Yellow River Basin 被引量:7
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作者 李伟平 薛永康 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第6期865-876,共12页
Two sets of numerical experiments using the coupled National Center for Environmental Prediction General Circulation Model (NCEP/GCM T42L18) and the Simplified Simple Biosphere land surface scheme (SSiB) were carr... Two sets of numerical experiments using the coupled National Center for Environmental Prediction General Circulation Model (NCEP/GCM T42L18) and the Simplified Simple Biosphere land surface scheme (SSiB) were carried out to investigate the climate impacts of fractional vegetation cover (FVC) and leaf area index (LAI) on East Asia summer precipitation, especially in the Yellow River Basin (YRB). One set employed prescribed FVC and LAI which have no interannual variations based on the climatology of vegetation distribution; the other with FVC and LAI derived from satellite observations of the International Satellite Land Surface Climate Project (ISLSCP) for 1987 and 1988. The simulations of the two experiments were compared to study the influence of FVC, LAI on summer precipitation interannual variation in the YRB. Compared with observations and the NCEP reanalysis data, the experiment that included both the effects of satellite-derived vegetation indexes and sea surface temperature (SST) produced better seasonal and interannual precipitation variations than the experiment with SST but no interannual variations in FVC and LAI, indicating that better representations of the vegetation index and its interannual variation may be important for climate prediction. The difference between 1987 and 1988 indicated that with the increase of FVC and LAI, especially around the YRB, surface albedo decreased, net surface radiation increased, and consequently local evaporation and precipitation intensified. Further more, surface sensible heat flux, surface temperature and its diurnal variation decreased around the YRB in response to more vegetation. The decrease of surface-emitting longwave radiation due to the cooler surface outweighed the decrease of surface solar radiation income with more cloud coverage, thus maintaining the positive anomaly of net surface radiation. Further study indicated that moisture flux variations associated with changes in the general circulation also contributed to the precipitation interannual variation. 展开更多
关键词 numerical simulation vegetation index interannual variation summer precipitation Yellow River basiu
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Origin of the Mushroom Stone Forest at the southeastern foot of the Little Sangpu Mountain in eastern Guangdong,China: A palaeo-sea-level indicator or not? 被引量:2
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作者 LI Jian-cheng WANG Wei ZHENG Yan-ming 《Journal of Mountain Science》 SCIE CSCD 2019年第3期487-503,共17页
The Mushroom Stone Forest, which consists of granite boulders looking like mushrooms with flared sidewalls, is located in eastern Guangdong China, and is a famous scenic spot that draws many tourists each year. The Mu... The Mushroom Stone Forest, which consists of granite boulders looking like mushrooms with flared sidewalls, is located in eastern Guangdong China, and is a famous scenic spot that draws many tourists each year. The Mushroom Stone Forest has been traditionally recognized as a collection of wave erosion landforms and used for the reconstruction of palaeo-sea-level changes along the coastal areas of eastern Guangdong in previous coastal researches. By combining in situ measurements of the aspect,vertical profile and height of boulder sidewalls,palaeo-coastal wave direction estimation, rock density determination, major elemental analysis, and petrographic thin section analysis, this paper presents an alternative origin for the Mushroom Stone Forest.Our results suggest that wave or wind erosion cannot offer a satisfactory explanation for the formation of the Mushroom Stone Forest; The boulders that make up the Mushroom Stone Forest originated from the corestones in the granite weathering crusts of the Little Sangpu Mountain; When the debris of the weathering crust was removed, the corestones are perched on rocky outcrops or half-buried by weathering debris beneath the natural land surface;The flared sidewall (concave vertical profile) of the boulders is a particular form developed in the foot zone of a half-buried boulder through increased chemical weathering beneath the land surface. A recent exposed half-buried boulder found in the study area provides convincing evidence to support this argument. Sea water reached the foot of the Sangpu Mountain during the Holocene transgression, but it merely provided a mechanism to erode the weathering debris from the bottom of the mushroom rocks and enhanced salt weathering that created tafoni on the boulders. These findings demonstrate that the boulders of the Mushroom Stone Forest are not sea stacks and cannot be served as a palaeo-sea-level indicator. 展开更多
关键词 BIOTITE granite MUSHROOM rock Sea level indictor Wave erosion Chemical weathering LITTLE Sangpu MOUNTAIN China
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Environmental evolution in the salt-water intrusion area south of Laizhou Bay since late Pleistocene 被引量:4
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作者 ZHANG Zulu LIU Enfeng +1 位作者 ZHANG Yan XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2008年第1期37-45,共9页
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses o... The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area. 展开更多
关键词 environmental evolution salt-water intrusion late Pleistocene south coastal plain of Laizhou Bay China
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Comprehensive Evaluation on Urban Sustainable Development of Harbin City in Northeast China 被引量:4
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作者 CAI Chunmiao SHANG Jincheng 《Chinese Geographical Science》 SCIE CSCD 2009年第2期144-150,共7页
It is an effective way in realizing urban coordinated and sustainable development to establish a series of in- dicators and to evaluate urban environmental and socioeconomic development. According to the characteristi... It is an effective way in realizing urban coordinated and sustainable development to establish a series of in- dicators and to evaluate urban environmental and socioeconomic development. According to the characteristics of Harbin City in Northeast China, an indicator system including five subsystems and 37 indicators was established for comprehensive evaluation on urban sustainable development. The development indexes of all urban subsystems and complex system were calculated quantitatively using the comprehensively integrated methods composed of Principle Component Analysis, Analytic Hierarchy Process and weighed index method, and then the comprehensive level of ur- ban sustainable development and the degree of urban interior coordination were analyzed. The results indicated that 1) the overall urban development presented an uptrend, however, the interior development was not well balanced from 1996 to 2006; 2) the development in each subsystem presented a strong fluctuation; and 3) the development in re- sources subsystem showed a downtrend. Based on those results, the suggestions of urban sustainable development were put forward at the end. 展开更多
关键词 sustainable development indicator system comprehensive evaluation Harbin City
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Driving factors of direct greenhouse gas emissions from China's pig industry from 1976 to 2016 被引量:5
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作者 DAI Xiao-wen Zhanli SUN Daniel MULLER 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第1期319-329,共11页
Livestock cultivation is a significant source of greenhouse gas(GHG) emissions, accounting for 14.5% of the total anthropogenic emissions. China is responsible for a considerable share of the global livestock emission... Livestock cultivation is a significant source of greenhouse gas(GHG) emissions, accounting for 14.5% of the total anthropogenic emissions. China is responsible for a considerable share of the global livestock emissions, particularly caused by pork production. We used the Kaya identity and the logarithmic mean Divisia index(LMDI) to decompose the national annual GHG emissions from enteric fermentation and manure management in pig farming in China from 1976 to 2016. We decomposed the sources of the emissions into five driving factors:(1) technological progress(e.g., feed improvement);(2) structural adjustment in the livestock sector;(3) structural adjustment in agriculture;(4) affluence;and(5) population growth. The results showed that the net GHG emissions from the pig sector in China increased 16 million tons(Mt) of carbon dioxide equivalents(CO2 eq) during the study period. The decomposition analysis revealed that structural adjustment in agriculture, growing affluence, and population growth contributed to an increase of the GHG emissions of pork production by 23, 41, and 13 Mt CO2 eq, respectively. The technological progress and structural changes in animal husbandry mitigated emissions by –51 and –11 Mt CO2 eq, respectively. Further technological progress in pig production and optimizing the economic structures are critical for further reducing GHG emissions in China's pig industry. Our results highlight the dominant role of technological changes for emission reductions in the pig farming. 展开更多
关键词 livestock production carbon emissions manure management pig farming LMDI decomposition
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Heavy Metal Contaminated Food Crops Irrigated with Wastewater in Peri Urban Areas, Zambia 被引量:8
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作者 Evaristo Mwaba Kapungwe 《Open Journal of Metal》 2013年第2期77-88,共12页
Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and... Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and crops at two peri urban areas in Zambia. Two study sites were New Farm Extension in Mufulira Town in the Copperbelt Province and Chilumba Gardens in Kafue Town in Lusaka Province. The heavy metals investigated were lead, copper, cobalt, nickel and chromium. These heavy metals were found to be higher than acceptable limits in wastewater used to irrigate crops and there are potential human health risks associated with consumption of heavy metal contaminated food crops which have implications on the livelihoods of people. Samples of water, soil and crops were collected and analysed for lead (Pb), copper (Cu), chromium (Cr), cobalt (Co) and nickel (Ni) using the Atomic Absorption Spectrometer (AAS). The data on heavy metals was analysed using mean, standard error and T-test. The results indicated that the levels of heavy metals in wastewater, soil and food crops were above acceptable limits at two study sites. It can be concluded that there was heavy metal contamination of wastewater, soil and food crops at the two peri-urban areas in Zambia. The study highlighted the actual levels of heavy metal contaminant uptake in food crops consumed by the peri urban population. The information from this study can be used by the relevant authorities to develop appropriate measures for monitoring and control of heavy metal contamination in wastewater irrigation farming systems in peri urban areas inZambia. 展开更多
关键词 HEAVY Metal Contamination WASTEWATER Soils Food CROPS IRRIGATION FARMING Peri Urban Areas Zambia
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