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Spatio-Temporal Change of Dispersal Areas of Greater Kudu (Tragelaphus strepsiceros) in Lake Bogoria Landscape, Kenya
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作者 Beatrice Chepkoech Cheserek George Morara Ogendi Paul Mutua Makenzi 《Open Journal of Ecology》 2024年第3期183-198,共16页
Decline in wildlife populations is manifest globally, regionally and locally. A wildlife decline of 68% has been reported in Kenya’s rangelands with Baringo County experiencing more than 85% wildlife loss in the last... Decline in wildlife populations is manifest globally, regionally and locally. A wildlife decline of 68% has been reported in Kenya’s rangelands with Baringo County experiencing more than 85% wildlife loss in the last four decades. Greater Kudu (Tragelaphus strepsiceros) is endemic to Lake Bogoria landscape in Baringo County and constitutes a major tourist attraction for the region necessitating use of its photo on the County’s logo and thus a flagship species. Tourism plays a central role in Baringo County’s economy and is a major source of potential growth and employment creation. The study was carried out to assess spatio-temporal change of dispersal areas of Greater Kudu (GK) in Lake Bogoria landscape in the last four years for enhanced adaptive management and improved livelihoods. GK population distribution primary data collected in December 2022 and secondary data acquired from Lake Bogoria National Game Reserve (LBNGR) for 2019 and 2020 were digitized using in a Geographic Information System (GIS). Measures of dispersion and point pattern analysis (PPA) were used to analyze dispersal of GK population using GIS. Spatio-temporal change of GK dispersal in LBNR was evident thus the null hypothesis was rejected. It is recommended that anthropogenic activities contributing to GK’s habitat degradation be curbed by providing alternative livelihood sources and promoting community adoption of sustainable technologies for improved livelihoods. 展开更多
关键词 spatio-temporal change Dispersal Greater Kudu (Tragelaphus Strepsiceros) Point Pattern Analysis (PPA) GIS
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Spatio-Temporal Changes in the Rice Planting Area and Their Relationship to Climate Change in Northeast China: A Model-Based Analysis 被引量:14
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作者 XIA Tian WU Wen-bin +5 位作者 ZHOU Qing-bo YU Qiang-yi Peter H Verburg YANG Peng LU Zhong-jun TANG Hua-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第7期1575-1585,共11页
Rice is one of the most important grain crops in Northeast China (NEC) and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over t... Rice is one of the most important grain crops in Northeast China (NEC) and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over the period of 1980-2010 and to analyze their relationship to climate change. To do so, the CLUE-S (conversion of land use and its effects at small region extent) model was ifrst updated and used to simulate dynamic changes in the rice planting area in NEC to understand spatio-temporal change trends during three periods: 1980-1990, 1990-2000 and 2000-2010. The changing results in individual periods were then linked to climatic variables to investigate the climatic drivers of these changes. Results showed that the NEC rice planting area expanded quickly and increased by nearly 4.5 times during 1980-2010. The concentration of newly planted rice areas in NEC constantly moved northward and the changes were strongly dependent on latitude. This conifrmed that climate change, increases in temperature in particular, greatly inlfuenced the shift in the rice planting area. The shift in the north limit of the NEC rice planting area generally followed a 1&#176;C isoline migration pattern, but with an obvious time-lag effect. These ifndings can help policy makers and crop producers take proper adaptation measures even when exposed to the global warming situation in NEC. 展开更多
关键词 spatio-temporal change rice planting area climate change Northeast China
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Spatio-Temporal Changes of Soil Salinity in Arid Areas of South Xinjiang Using Electromagnetic Induction 被引量:10
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作者 LI Xiao-ming YANG Jing-song +2 位作者 LIU Mei-xian LIU Guang-ming YU Mei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第8期1365-1376,共12页
The aim of this paper was to research the spatio-temporal changes in total soluble salt content (TS) in a typical arid region of South Xinjiang, China, where the climate is arid and soil salinization happens easily.... The aim of this paper was to research the spatio-temporal changes in total soluble salt content (TS) in a typical arid region of South Xinjiang, China, where the climate is arid and soil salinization happens easily. The total soluble salt content was interpreted by measurements made in the horizontal mode with EM38 and EM31. The electromagnetic induction (EM) surveys were made three times with the apparent soil electrical conductivity (ECa) measurements taken at 3 873 locations in Nov. 2008, 4 807 locations in Apr. 2009 and 6 324 locations in Nov. 2009, respectively. For interpreting the ECa measurements into total soluble salt content, calibtion sites were needed for EM survey of each time, e.g., 66 sites were selected in Nov. 2008 to measure ECa, and soils-core samples were taken by different depth layers of 0-10, 10-20 and 20-40 cm at the same time. On every time duplicate samples were taken at five sites to allevaite the local-scale variability, and soil temperatures in different layers through the profiles were also measured. Factors including TS, pH, water content, bulk density were analyzed by lab experiments. ECa calibration equations were obtained by linear regression analysis, which indicated that soil salinity was one primary concern to ECa with a determination coefficient of 0.792 in 0-10 cm layer, 0.711 in 10-20 cm layer and 0.544 in 20-40 cm layer, respectively. The maps of spatial distribution were predicted by Kriging interpolation, which showed that the high soil salinity was located near the drainage canal, which validated the trend effect caused by the irrigation canal and the drainage canal. And by comparing the soil salinity in different layers, the soluble salt accumulated to the top soil surface only in the area where the soil salinization was serious, and in the other areas, the soil salinity trended to increase from the top soil surface to 40 cm depth. Temporal changes showed that the soil salinity in November was higher than that in April, and the soil salinization trended to aggravate, especially in the top soil layer of 0-10 cm. 展开更多
关键词 spatio-temporal changes soil salinity South Xinjiang electromagnetic induction (EM) KRIGING
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Spatio-temporal changes of underground coal fires during 2008-2016 in Khanh Hoa coal field(North-east of Viet Nam) using Landsat time-series data 被引量:3
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作者 Tuyen Danh VU Thanh Tien NGUYEN 《Journal of Mountain Science》 SCIE CSCD 2018年第12期2703-2720,共18页
Underground coal fires are one of the most common and serious geohazards in most coal producing countries in the world. Monitoring their spatio-temporal changes plays an important role in controlling and preventing th... Underground coal fires are one of the most common and serious geohazards in most coal producing countries in the world. Monitoring their spatio-temporal changes plays an important role in controlling and preventing the effects of coal fires, and their environmental impact. In this study, the spatio-temporal changes of underground coal fires in Khanh Hoa coal field(North-East of Viet Nam) were analyzed using Landsat time-series data during the 2008-2016 period. Based on land surface temperatures retrieved from Landsat thermal data, underground coal fires related to thermal anomalies were identified using the MEDIAN+1.5×IQR(IQR: Interquartile range) threshold technique. The locations of underground coal fires were validated using a coal fire map produced by the field survey data and cross-validated using the daytime ASTER thermal infrared imagery. Based on the fires extracted from seven Landsat thermal imageries, the spatiotemporal changes of underground coal fire areas were analyzed. The results showed that the thermalanomalous zones have been correlated with known coal fires. Cross-validation of coal fires using ASTER TIR data showed a high consistency of 79.3%. The largest coal fire area of 184.6 hectares was detected in 2010, followed by 2014(181.1 hectares) and 2016(178.5 hectares). The smaller coal fire areas were extracted with areas of 133.6 and 152.5 hectares in 2011 and 2009 respectively. Underground coal fires were mainly detected in the northern and southern part, and tend to spread to north-west of the coal field. 展开更多
关键词 UNDERGROUND COAL fires spatio-temporal changeS Khanh Hoa COAL field (Viet Nam) LANDSAT time-series data
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Analysis on the Spatio-Temporal Changes of Sustainable Land Use in Tibet
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作者 GU Shixian XU Xia LIU Shuzhen 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期937-944,共8页
By constructing evaluation indicator system of sustainable land use of Tibet from three aspects of ecological environment, economic development, resources and social advancement, this article studies the following con... By constructing evaluation indicator system of sustainable land use of Tibet from three aspects of ecological environment, economic development, resources and social advancement, this article studies the following contents respectively in two dimensions of time and space: the changes of sustainable land use of Tibet in recent 20 years and spatial characteristics of sustainable land use of Tibet in 2002. The following conclusions can be drawn from evaluation results .① With regard to com- prehensive evaluation value of sustainable land use, the trend of Tibet sustainable land use evaluation values from 1983 to 2002 are very close to the comprehensive evaluation values of ecological environment, which is up trend; ② sustainable utilization degree of land use in eastern region of Tibet is much higher than that of western region. ③ the sustainable land use evaluation value of Nyingtri County is the highest, and the counties with relatively higher land sustainable use values include Lhasa, Lhoka, Chamdo. While Nakchu, Ngari, Shigatse counties have the relatively lower evaluation values; ④ By analyzing each evaluation indicator's weight on sustainable land use, it can be concluded that the key limiting factors of sustainable Tibet land resource utilization are land desertification, grassland degradation and low economic level. 展开更多
关键词 spatio-temporal changes sustainable land use ecological environment economic development resources and social advancement
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Land use change in Bohai Rim: a spatial-temporal analysis 被引量:7
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作者 ZHU Hui-yi, LI Xiu-bin, HE Shu-jin, ZHANG Ming (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期305-312,共8页
Based on RS and GIS methods, land use information for 1985 and 1995 was acquired from TM images and analyzed. Then on both spatial and temporal aspects, this paper analyzes land use change in three provinces of Hebei,... Based on RS and GIS methods, land use information for 1985 and 1995 was acquired from TM images and analyzed. Then on both spatial and temporal aspects, this paper analyzes land use change in three provinces of Hebei, Shandong and Liaoning and two municipalities of Beijing and Tianjin in the Bohai Rim covering the period of 1985 to 1995. The extent, rate, areal difference and trend of various types of land use changes in the region, as well as spatial changes of major types of land use, their distribution characteristics and regional orientation are revealed. The regional characteristics of land use are elaborated, so as to provide effective policy support for sustainable land use in the area around the Bohai Bay. 展开更多
关键词 Bohai Rim land use change spatio-temporal analysis
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Analysis of Characteristics of Spatio-temporal Evolution of Land Use in Inhabited Islands of Pearl River Estuary 被引量:3
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作者 LI Tao GAO Yi +3 位作者 LI Xiao-min LI Tuan-jie LI Xiao-ming YANG Qin 《Asian Agricultural Research》 2011年第10期11-18,共8页
Under the support of the remote sensing and geographical information system(GIS) techniques,we acquire the land use data in 1990 and 2008 regarding 6 inhabited islands,namely Longxue Island,Hengmen Island,Weiyuan Isla... Under the support of the remote sensing and geographical information system(GIS) techniques,we acquire the land use data in 1990 and 2008 regarding 6 inhabited islands,namely Longxue Island,Hengmen Island,Weiyuan Island,Qi'ao Island,Hengqin Island and Gaolan Island in Pearl River Estuary.By using dynamic degree of land use,land use change intensity,relative change rate and other indicators,we conduct quantitative description,and thus quantitatively and qualitatively analyse characteristics of temporal evolution and law of spatial pattern change concerning land use of each island.The study indicates that in the period 1990-2008,the area of construction land and water in 6 islands increased,while the area of agricultural land and unused land increased in some islands and decreased in others.The land use change shows spatial disparity;the holistic land use change degree in Hengmen Island is higher than that of other islands;the dynamic degree of land use,intensity of land use,and relative change rate differ in different islands. 展开更多
关键词 LAND use change REMOTE sensing spatio-temporal EVO
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基于“自然-社会”视角的陕西省土地利用变化碳核算与演变格局分析
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作者 奥勇 张龙 +3 位作者 王晓峰 吴彦芸 唐冰倩 张亦恒 《生态环境学报》 CSCD 北大核心 2024年第8期1306-1317,共12页
土地利用变化对碳源-汇有着重要的影响,在全球碳循环中扮演着重要的角色。为揭示土地利用变化对碳平衡的影响,以陕西省为研究区,基于资源清查、土壤调查、能源消费等多源数据,利用簿记模型和GIS软件核算了该省2002-2022年社会间接碳排... 土地利用变化对碳源-汇有着重要的影响,在全球碳循环中扮演着重要的角色。为揭示土地利用变化对碳平衡的影响,以陕西省为研究区,基于资源清查、土壤调查、能源消费等多源数据,利用簿记模型和GIS软件核算了该省2002-2022年社会间接碳排放和自然直接碳储量,并引入夜间灯光数据反演,揭示了不同地类及地类内部的碳密度差异与时空格局演变。结果表明:1)陕西省土地利用类型空间特征明显,林地和耕地占全省面积71.7%,2022年与2002年相比建设用地、林地、水域面积分别增加2.67×10^(5)、1.05×10^(6)、7.73×10^(3) hm^(2),耕地、草地、未利用地面积分别减少7.76×10^(5)、3.75×10^(5)、1.73×10^(5) hm^(2);2)研究期间陕西省土地利用相关碳吸收与碳排放严重失衡,土地利用相关年均碳汇量为4.98×10^(6) t,与林地面积的扩大及固碳能力的提升有关,年均碳排放量为3.10×10^(7) t,增长了7倍,与高排放能源的消耗有关;3)研究期间陕西省碳汇量在2007年后开始由负增长变为正增长,2017年后增长速度变快,碳排放量则一直处于高速增长,但受生态保护和减排政策等影响2017年后排放趋于稳定;4)研究期间陕西省地均碳密度表现为陕南秦巴山地>关中平原地区>陕北黄土高原,增长较为稳定的碳密度>60 t·hm^(−2)的地块主要集中在安康与商洛、汉中交界一带,碳排放区域主要集中在关中平原一带和陕西西北部,并在栅格单元空间上呈现扩张趋势。研究还发现,固碳主要依靠林地碳汇,当前陕西省碳排放趋于稳定,如何提升林草地的固碳能力将成为“双碳”目标实现的关键问题。 展开更多
关键词 土地利用变化 碳核算 地均碳密度 时空演变 陕西省
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MEPM模型:基于深度学习的多变量厄尔尼诺-南方涛动预测模型
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作者 方巍 张霄智 齐媚涵 《地球科学与环境学报》 CAS 北大核心 2024年第3期285-297,共13页
厄尔尼诺-南方涛动(ENSO)是发生在热带太平洋年际时间尺度的海-气相互作用的异常现象,并由Nino3.4指数表征其发生情况;除此之外,ENSO与众多极端气候事件密切相关。因此,有效的ENSO预测对于预防极端气候事件和深入研究全球气候变化具有... 厄尔尼诺-南方涛动(ENSO)是发生在热带太平洋年际时间尺度的海-气相互作用的异常现象,并由Nino3.4指数表征其发生情况;除此之外,ENSO与众多极端气候事件密切相关。因此,有效的ENSO预测对于预防极端气候事件和深入研究全球气候变化具有重要意义。然而,目前基于深度学习的ENSO预测大多数是预测一个指数或者单一变量,对于模拟多气候要素下的ENSO预测研究较少。通过提出一种利用多气候变量的ENSO预测模型——MEPM模型,其中包括多变量信息提取模块(MIEM)和时空融合模块(STFM),捕获不同气候变量在时空上的相互依赖性,进而提高ENSO预测的准确性。选取了纬向风应力异常(τ_(x))、经向风应力异常(τ_(y))、海表温度异常(SSTA)和海表下150 m温度异常(SSTA150)4个变量的距平值进行ENSO预测。结果表明:MEPM模型在提前11个月的Nino3.4指数相关技巧上分别比北美多模型集合中的动力预报系统CanCM4、CCSM3和GFDL-aer04高10%、20%和14%。此外,MEPM模型在中期Nino3.4指数相关技巧上显著优于其他深度学习模型,并可提供长达17个月的有效预测。 展开更多
关键词 气候变化 厄尔尼诺-南方涛动 多气候变量 深度学习 时空序列预测 卷积神经网络
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Spatio-temporal changes of NDVI and its relation with climatic variables in the source regions of the Yangtze and Yellow rivers 被引量:24
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作者 YANG Zhaoping GAO Jixi +4 位作者 ZHOU Caiping SHI Peili ZHAO Lin SHEN Wenshou OUYANG Hua 《Journal of Geographical Sciences》 SCIE CSCD 2011年第6期979-993,共15页
The source regions of the Yangtze and Yellow rivers are important water conservation areas of China. In recent years, ecological deterioration trend of the source regions caused by global climate change and unreasonab... The source regions of the Yangtze and Yellow rivers are important water conservation areas of China. In recent years, ecological deterioration trend of the source regions caused by global climate change and unreasonable resource development increased gradually. In this paper, the spatial distribution and dynamic change of vegetation cover in the source regions of the Yangtze and Yellow rivers are analyzed in recent 10 years based on 1-km resolution multi-temporal SPOTVGT-DN data from 1998 to 2007. Meanwhile, the cor- relation relationships between air temperature, precipitation, shallow ground temperature and NDVI, which is 3x3 pixel at the center of Wudaoliang, Tuotuohe, Qumalai, Maduo, and Dari meteorological stations were analyzed. The results show that the NDVI values in these two source regions are increasing in recent 10 years. Spatial distribution of NDVI which was consistent with hydrothermal condition decreased from southeast to northwest of the source regions. NDVI with a value over 0.54 was mainly distributed in the southeastern source region of the Yellow River, and most NDVI values in the northwestern source region of the Yangtze River were less than 0.22. Spatial changing trend of NDVI has great difference and most parts in the source regions of the Yangtze and Yellow rivers witnessed indistinct change. The regions with marked increasing trend were mainly distributed on the south side of the Tongtian River, some part of Keqianqu, Tongtian, Chumaer, and Tuotuo rivers in the source region of the Yangtze River and Xingsuhai, and southern Dari county in the source region of the Yellow River. The regions with very marked increasing tendency were mainly distributed on the south side of Tongtian Rriver and sporadically distributed in hinterland of the source re- gion of the Yangtze River. The north side of Tangula Range in the source region of the Yangtze River and Dari and Maduo counties in the source region of the Yellow River were areas in which NDVI changed with marked decreasing tendency. The NDVI change was positively correlated with average temperature, precipitation and shallow ground temperature. Shallow ground temperature had the greatest effect on NDVI change, and the second greatest factor influencing NDVI was average temperature. The correlation between NDVI and shallow ground temperature in the source regions of the Yangtze and Yellow rivers increased significantly with the depth of soil layer. 展开更多
关键词 source regions of the Yangtze and Yellow rivers NDVI spatio-temporal change temperature PRECIPITATION shallow ground temperature
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Rice cultivation changes and its relationships with geographical factors in Heilongjiang Province,China 被引量:8
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作者 LU Zhong-jun SONG Qian +4 位作者 LIU Ke-bao WU Wen-bin LIU Yan-xia XIN Rui ZHANG Dong-mei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2274-2282,共9页
Rice planting patterns have changed dramatically over the past several decades in northeast China (NEC) due to the combined influence of global change and agricultural policy. Except for its great implications for e... Rice planting patterns have changed dramatically over the past several decades in northeast China (NEC) due to the combined influence of global change and agricultural policy. Except for its great implications for environmental protection and climate change adaption, the spatio-temporal changes of rice cultivation in NEC are not clear. In this study, we conducted spatio-temporal analyses of NEC's major rice production region, Heilongjiang Province, by using satellite-derived rice cultivation maps. We found that the total cultivated area of rice in Heilongjiang Province increased largely from 1993 to 2011 and it expanded spatially to the northern and eastern part of the Sanjiang Plain. The results also showed that rice cultivation areas experienced a larger increase in the region managed by the Reclamation Management Bureau (RMB) than that managed by the local provincial government. Rice cultivation changes were closely related with those geographic factors over the investigated periods, represented by the geomorphic (slope), climatic (accumulated temperature), and hydrological (watershed) variables. These findings provide clear evidence that crop cultivation in NEC has been modified to better cope with the global change. 展开更多
关键词 paddy rice spatio-temporal change cultivation area geographical factors
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Analysis of spatio-temporal pattern and driving force of land cover change using multi-temporal remote sensing images 被引量:5
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作者 ZHOU QiMing & SUN Bo Department of Geography,Hong Kong Baptist University,Hong Kong,China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第S1期111-119,共9页
Landuse and land cover change is regarded as a good indicator that represents the impact of human activities on earth’s environment.When the large collection of multi-temporal satellite images has become available,it... Landuse and land cover change is regarded as a good indicator that represents the impact of human activities on earth’s environment.When the large collection of multi-temporal satellite images has become available,it is possible to study a long-term historical process of land cover change.This study aims to investigate the spatio-temporal pattern and driving force of land cover change in the Pearl River Delta region in southern China,where the rapid development has been witnessed since 1980s.The fast economic growth has been associated with an accelerated expansion of urban landuse,which has been recorded by historical remote sensing images.This paper reports the method and outcome of the research that attempts to model spatio-temporal pattern of land cover change using multi-temporal satellite images.The classified satellite images were compared to detect the change from various landuse types to built-up areas.The trajectories of land cover change have then been established based on the time-series of the classified land cover classes.The correlation between the expansion of built-up areas and selected economic data has also been analysed for better understanding on the driving force of the rapid urbanisation process.The result shows that,since early 1990s,the dominant trend of land cover change has been from farmland to urban landuse.The relationship between economic growth indicator(measured by GDP)and built-up area can well fit into a linear regression model with correlation coefficients greater than 0.9.It is quite clear that cities or towns have been sprawling in general,demonstrating two growth models that were closely related to the economic development stages. 展开更多
关键词 remote sensing change detection MULTI-temporal image processing spatio-temporal ANALYSIS land cover change PEARL River Delta urban expansion
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SPATIO-TEMPORAL CHANGE OF DROUGHT DISASTER IN CHINA IN RECENT FIFTY YEARS 被引量:1
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作者 Wang Jingai 1,2 , Sun Heng 1, Xu Wei 1 and Zhou Jinju 1 (1. Department of Resource & Environment Science, Beijing Normal University, Beijing 100875, China 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, Beijing Normal University, Beijing 100875, China) SunHui 《Natural Disaster Reduction in China》 2003年第1期11-17,共7页
In this paper, a drought disaster database, based on information from Chinese provincial newspaper, is established. And the spatio temporal pattern of drought disaster from 1949 to 2000 is reconstructed by using techn... In this paper, a drought disaster database, based on information from Chinese provincial newspaper, is established. And the spatio temporal pattern of drought disaster from 1949 to 2000 is reconstructed by using technology of digital mapping. The results show that the spatial pattern of drought disaster takes on discrepancy between the east and west of China, the serious disaster area lies in the north, especially in the west of Heilongjiang, the center of Inner Mongolia, the north of Hebei and Shaanxi, Ningxia; in the south of the country, drought disaster area lies in Anhui, Hubei, Hunan, Jiangxi, Henan, and Guizhou, the east of Sichuan, the center~east of Yunnan. The distribution of drought disaster in China has the tendency of extension to the west. Dynamic change of drought disaster takes on discrepancy between the south and north of the country. The amount of the drought disaster in the north of the Yangtze River is increasing, while the south is decreasing generally or changing invisibly. 展开更多
关键词 DROUGHT DISASTER AMOUNT of the DISASTER spatio temporal change
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河西走廊水资源-生态环境-社会经济系统耦合关系及时空分异
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作者 张文睿 孙栋元 +4 位作者 王亦可 杨俊 兰立军 靳虎甲 徐裕 《干旱区研究》 CSCD 北大核心 2024年第9期1527-1537,共11页
推进水资源、生态环境与社会经济系统协调发展为促进区域经济增长、社会进步和生态和谐与高质量发展提供技术支撑。文章基于修正耦合协调度模型评价河西走廊水资源-生态环境-社会经济系统耦合协调水平,运用灰色关联度模型和泰尔指数揭... 推进水资源、生态环境与社会经济系统协调发展为促进区域经济增长、社会进步和生态和谐与高质量发展提供技术支撑。文章基于修正耦合协调度模型评价河西走廊水资源-生态环境-社会经济系统耦合协调水平,运用灰色关联度模型和泰尔指数揭示驱动因素和空间异质性,并利用趋势面映射耦合协调度全域分布。结果表明:(1)由经济发展带动水资源-经济-生态系统综合发展水平逐年上升,综合发展指数由2006年0.29增长至2021年0.65。(2)河西走廊水资源子系统、经济子系统、生态子系统两两之间的耦合协调度呈不同趋势上升,水资源-生态-经济系统耦合度发展处于颉颃阶段向磨合阶段升级;协调度经历“轻度失调衰退-濒临失调衰退-勉强协调发展-初级协调发展-中级协调发展”五个阶段。(3)区域空间异质性逐渐发展为减小趋势,2021年空间分布表现出东南部发展优于西北部格局,金昌和张掖逐步成为河西发展优势区域。(4)城市化率、排污总量、节水灌溉面积对河西走廊水资源-生态环境-社会经济耦合发展起到较大的驱动作用。研究结果对河西走廊经济-生态-水资源系统协同发展具有一定的借鉴意义。 展开更多
关键词 修正耦合协调模型 水资源-生态环境-社会经济系统 时空演变规律 驱动因素 河西走廊
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NPP-VIIRS夜间灯光视角下突发公共事件影响与时空动态变化分析
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作者 刘文毅 靳奉祥 +3 位作者 刘耀辉 于建坤 申云 周炳任 《北京测绘》 2024年第3期289-293,共5页
夜间灯光数据已成为反映包括社会经济和能源消耗在内的人类活动的一个重要指标。针对突发公共事件对全国影响的动态监测区域化研究不足的问题,本研究基于2022年1—6月美国夜光传感器可见光近红外成像辐射搭载国家极轨卫星(NPP-VIIRS)采... 夜间灯光数据已成为反映包括社会经济和能源消耗在内的人类活动的一个重要指标。针对突发公共事件对全国影响的动态监测区域化研究不足的问题,本研究基于2022年1—6月美国夜光传感器可见光近红外成像辐射搭载国家极轨卫星(NPP-VIIRS)采集的夜间灯光数据,研究新冠疫情影响下夜间灯光的时空变化情况,揭示与分析疫情影响时空动态变化,并结合人口流动数据进行辅助验证。结果表明:以全国为空间尺度,夜间灯光强度与疫情发展呈负相关,且验证了基于NPP-VIIRS夜间灯光数据监测新冠疫情全国时空动态变化的可行性和准确性。本文研究成果可为相关部门应对今后可能突发的公共安全事件提供借鉴和参考。 展开更多
关键词 夜间灯光 突发公共事件 遥感 时空变化
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2001-2021年西宁市植被覆盖时空变化特征分析
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作者 包文金 李梦媛 司剑华 《绿色科技》 2024年第2期66-72,共7页
为揭示西宁市近20年植被覆盖的时空变化规律,为西宁市植被应对气候变化及生态良性发展提供科学指导,选取西宁市2001-2021年植被遥感数据,采用像元二分模型、最大值合成法及Slope趋势分析法等对西宁市植被覆盖变化特征进行分析,探究了研... 为揭示西宁市近20年植被覆盖的时空变化规律,为西宁市植被应对气候变化及生态良性发展提供科学指导,选取西宁市2001-2021年植被遥感数据,采用像元二分模型、最大值合成法及Slope趋势分析法等对西宁市植被覆盖变化特征进行分析,探究了研究期内西宁市植被覆盖的时空变化规律。结果表明:(1)在时间变化上,月际植被覆盖度呈现显著上升趋势,月总平均植被覆盖度在0.3412,由0.2963增长到了0.4222,其中7月份植被覆盖度(0.4222)最高,12月份(0.2963)最低。年均植被覆盖度呈现显著上升的趋势,由0.3350增长到0.3532。(2)在空间分布上,西宁市植被覆盖度呈现由西向东、由北向南增加的趋势。低植被覆盖区域呈现减少趋势,其余植被覆盖等级均呈现增加趋势。(3)在变化趋势上,2001-2021年植被覆盖度显著增加区域面积达到了33645.6 km^(2),占比为30.75%,植被覆盖度显著减少面积为30740.4 km^(2),占比为28.10%。2001-2021年植被覆盖度总体呈现上升趋势,未来西宁市生态环境建设的重点应该放在低植被覆盖区域。 展开更多
关键词 植被覆盖度 NDVI 时空变化 西宁市
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Spatiotemporal differentiation of changes in maize phenology in China from 1981 to 2010 被引量:12
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作者 LIU Yujie QIN Ya GE Quansheng 《Journal of Geographical Sciences》 SCIE CSCD 2019年第3期351-362,共12页
Spatio-temporal changes in the differentiation characteristics of eight consecutive phenological periods and their corresponding lengths were quantitatively analyzed based on long-term phenological observation data fr... Spatio-temporal changes in the differentiation characteristics of eight consecutive phenological periods and their corresponding lengths were quantitatively analyzed based on long-term phenological observation data from 114 agro-meteorological stations in four maize growing zones in China. Results showed that average air temperature and growing degree-days (GDD) during maize growing seasons showed an increasing trend from 1981 to 2010, while precipitation and sunshine duration showed a decreasing trend. Maize phenology has significantly changed under climate change: spring maize phenology was mainly advanced, especially in northwest and southwest maize zones, while summer and spring-summer maize phenology was delayed. The delay trend observed for summer maize in the northwest maize zone was more pronounced than in the Huang-Huai spring-summer maize zone. Variations in maize phenology changed the corresponding growth stages length: the vegetative growth period (days from sowing date to tasseling date) was generally shortened in spring, summer, and spring-summer maize, although to different degrees, while the reproductive growth period (days from tasseling date to mature date) showed an extension trend. The entire growth period(days from sowing date to mature date) of spring maize was extended, but the entire growth periods of summer and spring-summer maize were shortened. 展开更多
关键词 MAIZE PHENOLOGY CLIMATE change spatio-temporal DIFFERENTIATION China
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1962-2010年玛纳斯流域耕地景观的时空变化分析 被引量:39
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作者 李均力 姜亮亮 +3 位作者 包安明 常存 白洁 刘海隆 《农业工程学报》 EI CAS CSCD 北大核心 2015年第4期277-285,共9页
为分析近几十年来玛纳斯流域水资源开发密集开发条件下耕地景观的时空变化,采用1962年、1977年、1989年、2000年和2010年5期遥感影像进行土地利用制图,并针对耕地信息,分别从时间变化过程、类型转化关系、空间格局等方面分析了近50 a来... 为分析近几十年来玛纳斯流域水资源开发密集开发条件下耕地景观的时空变化,采用1962年、1977年、1989年、2000年和2010年5期遥感影像进行土地利用制图,并针对耕地信息,分别从时间变化过程、类型转化关系、空间格局等方面分析了近50 a来面积变化的时空特征,从气候变化与灌区建设的角度探讨了水资源空间配置与耕地扩张的关系。结果表明:1)近50 a来耕地和建设用地面积持续增加,未利用地、湿地和冰川雪地持续减少,草地在前20年增加、后30年减少;土地利用的变化程度总体上由剧烈逐渐趋于缓和;2)整体上耕地的变化由双向转化期逐渐过渡到单向转入期,草地和未利用地为各期主要转入类型,建设用地和草地为主要转出类型,各期的转入面积远大于转出面积,耕地总面积持续、快速增长。3)耕地扩张的重心由城市周边转向荒漠地区、由上游地区逐渐转移到下游,先后在昌吉、呼图壁、沙湾县、主要河流两岸及北部荒漠地区扩张,耕地景观也由杂乱破碎转的斑块转为成片连续的耕地带,耕地在景观中的优势进一步加强。4)耕地面积的扩张与降水和河川径流量的增加有关,耕地的扩张速度与方向与水库的空间分布及建成时间有明显的相关性,水库及灌渠建成的后一个时段往往会伴随一轮耕地的快速扩张。流域内水资源开发的潜力不足,已不能满足耕地的大规模扩张。适当控制耕地规模、优化用水结构、提高水资源利用效率,是集约化农业发展、生态环境保护的关键。 展开更多
关键词 土地利用 遥感 气候变化 水利设施 耕地 时空变化特征 玛纳斯流域
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1989-2014年赛里木湖水面面积的时序变化特征 被引量:15
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作者 王宇 李均力 +3 位作者 郭木加甫 包安明 胡汝骥 赵胜楠 《干旱区地理》 CSCD 北大核心 2016年第4期851-860,共10页
利用多时相中高分辨率遥感数据分析湖泊面积的时序变化是当前湖泊变化研究的热点之一。采用1989-2014年的多源卫星遥感资料对赛里木湖的水面面积变化进行制图,分析长时段内湖泊面积的时空变化特征,并探讨湖泊面积对气候变化的响应。研... 利用多时相中高分辨率遥感数据分析湖泊面积的时序变化是当前湖泊变化研究的热点之一。采用1989-2014年的多源卫星遥感资料对赛里木湖的水面面积变化进行制图,分析长时段内湖泊面积的时空变化特征,并探讨湖泊面积对气候变化的响应。研究表明:尽管赛里木湖面积变化相对较小,然而较长时序遥感数据能够很好的描述赛里木湖面积的年度和季节性变化特征。26 a来湖泊的年际、季节面积变化总体呈上升趋势,其中年面积变化为0.165 km^2·a^(-1),并分别在1993-1998和2001-2005年处于快速上升的阶段;从季节性变化来看,1~3月份处于雪冰覆盖期,6~8月份是面积最大的时期。湖泊边界变化与周边地势有关,边界外扩的区域主要分布在湖泊西部、西北部等地势低且平坦的草原地带,且湖岸坍塌与崩岸的区域与研究区盛行的风向相对应。近30 a的气候资料表明,湖泊萎缩、扩张变化与气候变化有很好的相关性,较好地响应了区域气候暖湿的变化。 展开更多
关键词 赛里木湖 湖泊面积 时空特征 气候变化 遥感
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广东省1996-2012年农业用地碳汇效应及时空变化特征 被引量:6
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作者 叶延琼 章家恩 +2 位作者 陈丽丽 秦钟 赵本良 《水土保持学报》 CSCD 北大核心 2014年第5期139-146,共8页
为了定量测定广东省农业用地碳汇效应的时空差异,运用1996-2012年的农业用地面积、主要农作物产量、年均气温和年均降水量数据以及2008年21个地级市的相关统计数据,对广东省不同农业用地植被固定CO2的量进行分析。结果表明:农业用地植... 为了定量测定广东省农业用地碳汇效应的时空差异,运用1996-2012年的农业用地面积、主要农作物产量、年均气温和年均降水量数据以及2008年21个地级市的相关统计数据,对广东省不同农业用地植被固定CO2的量进行分析。结果表明:农业用地植被固定CO2的总量一直处于波动状态,但总体表现为增加态势,由1996年的3.43×1010 t增加到2012年的3.94×1010 t,年均增长率为0.82%。林地和园地在CO2固定过程中占绝对优势,二者固定CO2的量占全省农业用地固定CO2总量的99.95%以上,是农业用地植被固定CO2最重要的贡献者。耕地对CO2的固定主要由稻谷、糖蔗和蔬菜三大作物体现,三者固定的CO2占全省农作物固定CO2总量的90%以上。年均降水量对林地和园地固定CO2总量的影响程度要大于其面积变化的影响,而草地固定CO2的量与草地面积呈现高度一致性。广东省农业用地植被固定CO2的量具有显著的区域差异,呈现出北部山区高,珠三角地区、粤东及粤西地区低的总体特征。此外,全省农业用地固定CO2量的空间分布与林地固定CO2量的空间分布具有较高的一致性,说明一个地区林地占农业用地面积比例越大,则植被固定CO2的量越高。 展开更多
关键词 农业用地 碳汇 时空变化 广东省
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