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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 Evolution of Marine Fishery Industry Ecosystem Vulnerability in the Bohai Rim Region 被引量:5
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作者 LI Bo JIN Xiaoming 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1052-1064,共13页
The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this p... The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to 2015.The results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the west.According to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, etc.Then, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction. 展开更多
关键词 MARINE FISHERY MARINE INDUSTRY ecosystem vulnerability spatio-temporal evolution Bohai RIM Region
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Spatio-temporal evolution of ecologically-sustainable land use in China's Loess Plateau and detection of its influencing factors 被引量:5
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作者 QU Lu-lu LIU Yan-sui CHEN Zong-feng 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1065-1074,共10页
Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to surv... Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China's Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What's more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment. 展开更多
关键词 Ecologically-sustainable land use spatio-temporal evolution influencing factor Population migration LOESS PLATEAU
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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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“stppSim”: A Novel Analytical Tool for Creating Synthetic Spatio-Temporal Point Data
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作者 Monsuru Adepeju 《Open Journal of Modelling and Simulation》 2023年第4期99-116,共18页
In crime science, understanding the dynamics and interactions between crime events is crucial for comprehending the underlying factors that drive their occurrences. Nonetheless, gaining access to detailed spatiotempor... In crime science, understanding the dynamics and interactions between crime events is crucial for comprehending the underlying factors that drive their occurrences. Nonetheless, gaining access to detailed spatiotemporal crime records from law enforcement faces significant challenges due to confidentiality concerns. In response to these challenges, this paper introduces an innovative analytical tool named “stppSim,” designed to synthesize fine-grained spatiotemporal point records while safeguarding the privacy of individual locations. By utilizing the open-source R platform, this tool ensures easy accessibility for researchers, facilitating download, re-use, and potential advancements in various research domains beyond crime science. 展开更多
关键词 OPEN-SOURCE Synthetic Data CRIME spatio-temporal patterns Data Privacy
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Spatio-temporal patterns of drought in North Xinjiang, China, 1961–2012 based on meteorological drought index 被引量:8
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作者 WU Yanfeng Batur BAKE +1 位作者 ZHANG Jusong Hamid RASULOV 《Journal of Arid Land》 SCIE CSCD 2015年第4期527-543,共17页
Drought, which is one of the most frequently occurring severe hazards with long time scales and cov- ering wide geographical areas, is a natural phenomenon resulting in significant economic losses in agriculture and i... Drought, which is one of the most frequently occurring severe hazards with long time scales and cov- ering wide geographical areas, is a natural phenomenon resulting in significant economic losses in agriculture and industry. Drought is caused by an imbalance between the inputs of and the demand for water which is insufficient to meet the demands of human activities and the eco-environment. As a major arid and semi-arid area and an important agricultural region in Northwest China, North Xinjiang (NX) shows great vulnerability to drought. In this paper, the characteristics of inter-annual and seasonal drought were analyzed in terms of drought occurrence and drought coverage, by using the composite index of meteorological drought and the data of daily precipitation, air temperature, wind speed, relative humidity and sunshine duration from 38 meteorological stations during the period 1961-2012. Trend analysis, wavelet analysis and empirical orthogonal function were also applied to investigate change trend, period and regional characteristics, respectively. In NX, annual and seasonal drought occurrence and drought coverage all showed a decreasing trend that was most significant in winter (with rates of-0.26 month/10a and -15.46%, respectively), and drought occurrence in spring and summer were more frequent than that in autumn and winter. Spatially, drought was severe in eastern regions but mild in western regions of NX. Annual and seasonal drought occurrence at 38 meteorological stations displayed decreasing trends and were most significant in "Shi- hezi-Urumqi-Changji", which can help to alleviate severe drought hazards for local agricultural production and improve human livelihood. NX can be approximately classified into three sub-regions (severe drought region, moder- ate drought region and mild drought region), which were calculated from annual drought frequencies. The cross wavelet transform suggested that SOl (Southern Oscillation Index), AOI (Arctic Oscillation Index), AAOI (Antarctic Oscillation Index), PAOI (Pacific/North American Oscillation Index) and NAOI (North Atlantic Oscillation Index) have significant correlation with the variation of drought occurrence in NX. To prevent and mitigate the occurrence of drought disasters in NX, agricultural and government managers should pay more attention to those drought events that occur in spring and summer. 展开更多
关键词 DROUGHT spatio-temporal pattern drought indices North Xinjiang
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Spatial-temporal evolution of vegetation evapotranspiration in Hebei Province,China 被引量:4
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作者 WANG Qian-feng TANG Jia +6 位作者 ZENG Jing-yu QU Yan-ping ZHANG Qing SHUI Wei WANG Wu-lin YI Lin LENG Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第9期2107-2117,共11页
Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resou... Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resource cycles. The time-series data set from the remote sensing MOLDS product (MOD16) was used to study the spatial-temporal evolution of vegetation evapotranspiration in salinized areas during 2000-2014 by analyzing the variability, spatial patterns and Mann-Kendall (MK) nonparametric trends for the time series. The results indicate that inter-annual and intra-annual variations of ET across various vegetated areas show seasonal changes, with the abnormal months identified. The Cultivated land displays a greater degree of spatial heterogeneity and the spatial pattern of ET in the area covered by broadleaved deciduous forests corresponds to a higher ET rate and increased water consumption. Awidespread decline of ET is observed only in cultivated areas. However, agricultural cultivation doesn't worsen water shortage and soil salinization problems in the region, and water shortage problems are worsening for other vegetated areas. This research provides a basis of reference for the reasonable allocation of water resources and restructuring of vegetation patterns in salinized areas. 展开更多
关键词 EVAPOTRANSPIRATION Hebei Province MODIS spatial pattern VEGETATION spatial-temporal evolution
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Methods to evaluate the impacts of physio- geographical pattern on spatio-temporal disparity of regional development 被引量:2
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作者 LI Guosheng GUO Zhaocheng LIAO Heping 《Journal of Geographical Sciences》 SCIE CSCD 2008年第2期225-236,共12页
With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic... With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic geography, and also has been the task for Chinese government to handle. Nevertheless, to quantitatively assess the impacts of physio-geographical patterns (PGP) on the regional development disparity has been ignored for a long time. In this paper, a quantitative method was adopted to assess the marginal effects of the PGP on spatio-temporal disparity using the partial determination coefficients. The paper described the construction of the evaluation model step by step following its key scientific thinking. Total GDP, per capita GDP, primary industrial output value and secondary industrial output value were employed in this study as the indicators to reflect the impacts of PGP on the regional development disparity. Based on the evaluation methods built by researchers, this study firstly analyzed the temporal impacts of the PGP on spatio-temporal disparity of the regional development in China during the past 50 years, and then explained the spatial differences at each development stage. The results show that the spatio-temporal disparity in China is highly related to the PGP, and that the marginal contribution rate could be employed as an effective way to quantitatively assess the impact of the PGP on spatio-temporal disparity of the regional development. 展开更多
关键词 physio-geographical pattern regional development spatio-temporal disparity marginal contribution rate
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Spatio-temporal point pattern analysis on Wenchuan strong earthquake 被引量:2
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作者 Peijian Shi Jie Liu Zhen Yang 《Earthquake Science》 CSCD 2009年第3期231-237,共7页
For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aflershocks with magnitude M≥4.0, M≥4.5... For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aflershocks with magnitude M≥4.0, M≥4.5, and M≥5.0. It is found that these data exhibit the spatio-temporal clustering on a certain distance scale and on a certain time scale. In particular, the space-time interaction obviously strengthens when the distance is less than 60 km and the time is less than 260 h for the first two aftershock sequences; however, it becomes strong when the distance scale is less than 80 km and the time scale is less than 150 h for the last aftershock sequence. The completely spatial randomness analysis on the data regardless of time component shows that the spatial clustering of the aftershocks gradually strengthens on the condition that the distance is less than 60 km. The results are valuable for exploring the occurrence rules of the Wenchuan strong earthquake and for predicting the aftershocks. 展开更多
关键词 Wenchuan earthquake completely spatial randomness spatio-temporal point pattern K-FUNCTION
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Temporal and Spatial Evolution of Lakes in the Bashang Plateau for Nearly Recent 30 Years
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作者 Xiujuan Li Sugai Gao +2 位作者 Wenli Li Guifu Qiu Zhiyuan Tian 《Journal of Water Resource and Protection》 CAS 2022年第10期698-708,共11页
Lakes are important ecological water sources in the Bashang Plateau. Its expansion or shrinkage directly affects the ecological security of the plateau and its surrounding areas. In this study, Landsat images from 198... Lakes are important ecological water sources in the Bashang Plateau. Its expansion or shrinkage directly affects the ecological security of the plateau and its surrounding areas. In this study, Landsat images from 1984 to 2015 were selected to monitor the area of lakes in the Bashang Plateau and to analyze the spatiotemporal evolution and driving forces of lakes in the Bashang Plateau. The results showed that there were 47 lakes in the Bashang Plateau in 2015, with a total area of 37.63 km2, mainly distributed in the central and western regions of the region. From 1984 to 2015, the lakes in Bashang Plateau showed a shrinking trend. At the same time, there are obvious stage differences in lake changes. During 1984-1996, the number of lakes increased by 99 and the total area increased by 124.43 km2. From 1996 to 2015, the number of lakes decreased by 142, and the total area decreased by 183.96 km2. Before 1996, climate change was the dominant factor. However, the shrinkage of lakes after 1996 is the result of climate change and human activities. Among them, the large-scale planting of water consuming crops such as vegetables is the main human activity mode leading to lake shrinkage. This study will help to understand the expansion and contraction factors of the Bashang Plateau lakes in Hebei province and provide a reference for the future protection and management of the lakes. 展开更多
关键词 Bashang Plateau Lake Area Spatial and temporal patterns evolution Driving Force
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Multi-scale regionalization based mining of spatio-temporal teleconnection patterns between anomalous sea and land climate events
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作者 徐枫 石岩 +3 位作者 邓敏 龚健雅 刘启亮 金瑞 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2438-2448,共11页
Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-de... Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-dependency in this kind of pattern is still not well handled by existing work. Therefore, in this study, the multi-scale regionalization is embedded into the spatio-temporal teleconnection pattern mining between anomalous sea and land climatic events. A modified scale-space clustering algorithm is first developed to group climate sequences into multi-scale climate zones. Then, scale variance analysis method is employed to identify climate zones at characteristic scales, indicating the main characteristics of geographical phenomena. Finally, by using the climate zones identified at characteristic scales, a time association rule mining algorithm based on sliding time windows is employed to discover spatio-temporal teleconnection patterns. Experiments on sea surface temperature, sea level pressure, land precipitation and land temperature datasets show that many patterns obtained by the multi-scale approach are coincident with prior knowledge, indicating that this method is effective and reasonable. In addition, some unknown teleconnection patterns discovered from the multi-scale approach can be further used to guide the prediction of land climate. 展开更多
关键词 CLIMATE sequences ANOMALOUS climatic EVENTS spatio-temporal teleconnection patterns MULTI-SCALE REGIONALIZATION
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Temporal and Spatial Evolution of Precursory Anomalies of the Wenchuan MS8.0 Earthquake and Their Mechanical Analysis
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作者 Zhang Xiaotao Liu Jie +4 位作者 Song Zhiping Xue Yan Zhang Yongxian Yan Rui Yuan Zhengyi 《Earthquake Research in China》 CSCD 2018年第2期212-226,共15页
In order to study the spatiotemporal evolution of the precursory anomalies 10 years before the Wenchuan M_S8. 0 earthquake in 2008, the epicentral distance of the precursory anomalies is calculated by using the geomet... In order to study the spatiotemporal evolution of the precursory anomalies 10 years before the Wenchuan M_S8. 0 earthquake in 2008, the epicentral distance of the precursory anomalies is calculated by using the geometric center of the rupture region and the elliptical centerline of the aftershock region. The result shows, precursor anomalies gradually increased about 2 years before the Wenchuan earthquake. The ratio of abnormal items is greater than 25% in the near source area (about twice the source scale) and 17%-24% in the remote area (about 3-5 times the source scale). There are three different stages of spatiotemporal evolution of precursory anomalies. During the α stage (including α_1 and α_2,between 700 to 3000 days before the main earthquake),the anomalies are mainly distributed in the southwest and northwest area of the Wenchuan aftershocks area. It is shown that the precursors of the far source region and the near source area have the characteristics of outward expansion. During the β stage (between 300 to 700 days before the main earthquake), the anomalies are distributed in the southwest and northern region of the aftershock region, showing a large range of anomalies. During the γ stage (including γ_1 and γ_2, 300 days before the main earthquake),the range of anomaly distribution is wide,and the anomalies are distributed in the southwest and northeast of the aftershock area. The anomalies converged to epicenter (γ_1) in the far source region and expand outwards (γ_2) in the near source region. Results of the experimental study and mechanical analysis of earthquake preparation process indicate that the three-stage characteristics of precursory anomalies in the process of earthquake preparation may be controlled by the seismogenic body,which is a form of expression in the process of earthquake preparation and a universal featureduring the earthquake preparation process,which has a certain guiding role in earthquake prediction. 展开更多
关键词 WENCHUAN M S8.0 EARTHQUAKE Precursor ANOMALY spatio-temporal evolution Three-stages feature
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Spatio-Temporal Patterns of Wildlife Road Mortality in Golestan National Park-North East of Iran
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作者 Vahed Dehghani Kazemi Hamidreza Jafari Ahmadreza Yavari 《Open Journal of Ecology》 2016年第6期312-324,共13页
Nowadays, wildlife road mortality is acknowledged as a main source of threatening long-term survival of wildlife. This paper as the first to analysis wild life vehicle collisions in Iran, aims to reconstruct and inter... Nowadays, wildlife road mortality is acknowledged as a main source of threatening long-term survival of wildlife. This paper as the first to analysis wild life vehicle collisions in Iran, aims to reconstruct and interpret the spatio-temporal patterns of WVCs on Asiaei highway in Golestan National Park (GNP). With the collaboration of environmental protection department of GNP, we identified about 1900 WVC Records involving 34 different species of mammals, birds, reptiles and amphibians between 2004 and 2013. Mammals were involved in more than 50% of overall WVCs, among which wild boar (Sus scrofa), Golden Jackal (Canis aureus), Red Fox (Vulpes vulpes), hedgehog (Erinaceus concolor), stone marten (Martes foina) and porcupine (Hystrix indica) were involved in more than 90% of mammals’ mortalities;So, we focused on analyzing spatio-temporal pattern of vehicle collisions of these six mammal species. During the study period, these species have undergone 95% increase in road mortalities, averagely. Detailed temporal analyses exhibited an increasing trend of road mortalities from spring to summer and then a reducing one to late winter. It was shown that a large number of collisions occurred in holiday periods when recreational trips considerably increased the traffic volume of Asiaei highway. Preliminary inspection of spatial patterns using Kernel density analysis revealed six collision hotspots, mostly located in the road bends with densely forested land cover on both sides;the promenades along the road seemed to play a significant role too. Scale dependency analyses of collision patterns, demonstrated clustering pattern at micro scales less than 10 km, randomness at meso scales 10 - 20 km and both regularity and clustering at macro scales more than 20 km. This paper suggests that road mortality of common species in GNP is a momentous issue, which needs to be considered by relevant governmental and public organizations. We also emphasize that the analyses of spatial and temporal patterns of WVCs are fundamentals to plan for mitigate wildlife road mortality. 展开更多
关键词 Golestan National Park Wildlife Vehicle Collision (WVC) spatio-temporal pattern K-FUNCTION
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Gas monitoring data anomaly identification based on spatio-temporal correlativity analysis 被引量:3
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作者 Shi-song ZHU Yun-jia WANG Lian-jiang WEI 《Journal of Coal Science & Engineering(China)》 2013年第1期8-13,共6页
关键词 相关性分析方法 监测数据 瓦斯监测 时空 异常识别 气体传感器 采煤工作面 自动识别技术
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Spatio-temporal Variability of Disastrous Convective Weather in China from 1961 to 2016
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作者 Feng KONG 《Asian Agricultural Research》 2019年第3期30-36,40,共8页
Based on the data of hail,gale,thunderstorm and lightning days in 2 481 stations in China from 1961 to 2016,the spatial and temporal distribution characteristics,periodicity and climate abruption characteristics of fo... Based on the data of hail,gale,thunderstorm and lightning days in 2 481 stations in China from 1961 to 2016,the spatial and temporal distribution characteristics,periodicity and climate abruption characteristics of four kinds of disastrous convective weather in China were analyzed by various mathematical statistics methods. The results showed that in time,the days of four kinds of disastrous convective weather in China decreased,and the hail and thunderstorm days were characterized by " increasing firstly and then decreasing" from 1961 to 2016. The hail,gale,thunderstorm and lightning days in China had oscillation cycles of 3-5,2-3,1-2 and 1-4 a respectively,and the hail and thunderstorm days changed suddenly in 2002 and 1992 respectively. In space,the Qinghai-Tibet Plateau and western Sichuan were the highvalue distribution areas of hail,gale and thunderstorm days. The high-value distribution areas of thunderstorm days were also distributed to the south of the Yangtze River. South China and its southwestern regions at the same latitude were the high-value distribution areas of lightning days. In terms of trend,the hail days in China showed a decreasing trend mainly in the Qinghai-Tibet Plateau. The gale days in China decreased in the east,was unchanged in the central region,and increased and decreased alternately in the west. The thunderstorm days in China increased in Tibet,North China,Chongqing,Zhejiang and northwestern Heilongjiang. The lightning days in China decreased obviously to the south of the Yangtze River. In terms of the fluctuation,the hail days fluctuated greatly in the southeast. The gale days fluctuated greatly to the east of Hu Huanyong line. The thunderstorms days in China fluctuated greatly in the northwest and slightly in the southeast. In addition to the small fluctuation in northern Xinjiang and South China,the lightning days fluctuated greatly in other regions of China. 展开更多
关键词 Disastrous weather Hail-gale-thunderstorm-lightning spatio-temporal pattern Characteristic of periodic OSCILLATION Mutation test
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中国旅游产业链发展格局演变及空间效应研究
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作者 刘佳 安珂珂 +1 位作者 赵青华 陆嘉欣 《地理与地理信息科学》 CSCD 北大核心 2024年第3期122-134,共13页
产业链现代化是建设现代化产业体系及助推中国式现代化进程的重要抓手,全面揭示旅游产业链发展现状及其影响因素对于提升旅游产业链现代化水平具有实际意义。该文以2001一2019年中国30个省域为研究对象,构建涵盖旅游供需链、企业链、空... 产业链现代化是建设现代化产业体系及助推中国式现代化进程的重要抓手,全面揭示旅游产业链发展现状及其影响因素对于提升旅游产业链现代化水平具有实际意义。该文以2001一2019年中国30个省域为研究对象,构建涵盖旅游供需链、企业链、空间链、价值链的旅游产业链发展水平评价指标体系,利用核密度估计、Dagum基尼系数及其分解、探索性空间数据分析等方法对中国旅游产业链发展的时序演变规律、空间差异特征及空间关联格局进行分析,并运用空间杜宾模型探讨影响中国旅游产业链发展的主要因素及其空间效应。研究发现:①中国旅游产业链发展水平呈平稳提升态势,表现出由东部地区向中部、东北及西部地区递减的分布态势。②中国旅游产业链发展的总体区域差异呈波动缩小趋势,区域间差异是其主要来源,且东部与西部地区旅游产业链发展的区域间差异最大;东部地区旅游产业链发展的区域内差异最大,西部、东北地区次之,中部地区最小。③中国旅游产业链发展具有空间相关性和空间集聚特征,供给、需求、创新、政策等层面因素是影响中国旅游产业链发展的主要因素。其中,旅游资源赋、旅游人力资本、互联网、产业融合发展与对外开放水平有利于推进本地区旅游产业链发展,旅游需求总量、旅游需求结构与对外开放水平能通过正向空间溢出效应带动邻近地区旅游产业链发展。 展开更多
关键词 旅游产业链 时空格局 格局演变 影响因素 空间效应
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黄河流域气溶胶时空异质性及影响因素分析
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作者 李健 全智雯 +1 位作者 周书贵 马玉荣 《郑州大学学报(工学版)》 CAS 北大核心 2024年第3期29-37,共9页
基于大尺度黄河流域的长时序气溶胶光学厚度(AOD)的分析较少,且因素分析也集中在气象条件方面,针对该问题,搜集了MODIS气溶胶产品数据,基于地理加权回归模型(GWR)分析了整个黄河流域的时空变化特征,定量探讨了地理环境、自然气象和社会... 基于大尺度黄河流域的长时序气溶胶光学厚度(AOD)的分析较少,且因素分析也集中在气象条件方面,针对该问题,搜集了MODIS气溶胶产品数据,基于地理加权回归模型(GWR)分析了整个黄河流域的时空变化特征,定量探讨了地理环境、自然气象和社会经济对AOD的综合影响。结果表明:黄河流域AOD整体为下降趋势,由2001年的0.38下降至2020年的0.22。AOD的变化具有明显的季节性,春夏季高于秋冬季,这可能是气温、大气扩散条件和植被覆盖等因素共同作用的结果;从空间分布角度来看,研究区AOD为自西向东呈现梯度递增分布,与流域DEM分布趋势相反,说明地形与气溶胶之间有密切关联。基于GWR模型的研究结果表明:地形植被对整个黄河流域AOD影响程度最大,其次为社会经济、自然气象。针对黄河流域内重点城市的研究结果表明:不同城市气溶胶光学厚度的月际变化有较大差异,流域上游城市西宁、银川和包头的AOD水平较低,冬季AOD最高,夏季AOD最低,而中下游城市夏季AOD最高,冬季最低。 展开更多
关键词 MODIS 气溶胶光学厚度 时空分布 影响因素 黄河流域
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青藏高原人类工程活动强度定量评价及时空格局演变
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作者 汪东川 王思润 +6 位作者 王志恒 赵爽 孙苗苗 魏奥泽 许家承 俞长锦 贾世杰 《生态学报》 CAS CSCD 北大核心 2024年第10期4142-4156,共15页
青藏高原是世界上最高的高原,复杂多样的地貌结构一定程度上限制着人类工程活动,而人类工程活动又会对青藏高原脆弱敏感的生态环境产生影响。基于能源工程、社会经济发展、交通路网等数据,结合青藏高原科考实地考察情况,旨在建立一套县... 青藏高原是世界上最高的高原,复杂多样的地貌结构一定程度上限制着人类工程活动,而人类工程活动又会对青藏高原脆弱敏感的生态环境产生影响。基于能源工程、社会经济发展、交通路网等数据,结合青藏高原科考实地考察情况,旨在建立一套县域尺度下的青藏高原人类工程活动强度评价指标体系,基于层次分析法及专家打分法,结合各类空间分析方法对各指标因子赋权,并以县域为单元探讨青藏高原2000年、2005年、2010年、2015年、2020年人类工程活动强度时空变化,全面科学地评估青藏高原人类工程活动强度的时空格局演变特征。结果表明:1)以能源工程建设强度、市政基础设施建设强度及交通基础设施建设强度3个一级指标和10个二级指标、19个三级指标建立的定量评价指标体系能够很好地反应研究区人类工程活动强度在空间上的分异。2)评价表明,2000—2020年间青藏高原整体人类工程活动强度呈增强趋势,且增速不断加快;3)青藏高原人类工程活动强度东西部差异明显,受资源配置和人口分布等因素的影响,西宁和拉萨在经济发展和基础设施建设方面具有明显优势,在人类工程活动强度方面呈以“西宁-拉萨”为轴线的中心区域向外不规则递减的空间格局;4)人类工程活动强度的增加与青藏高原地区快速的城镇化发展和工程建设规模的扩大密切相关,随着经济和社会发展的推动,能源需求和基础设施建设不断增长,使得人类工程活动在青藏高原地区的不断增强,表明其对生态的影响也逐渐增大,在大力开发能源和建设工程时应重点关注和保护生态环境。 展开更多
关键词 人类工程活动 时空格局 评价指标体系 定量评价 青藏高原
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西南山区乡村贫困地域系统时空演化格局研究——以云南省镇沅县为例
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作者 潘卓 廖和平 +1 位作者 刘愿理 朱琳 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期2-14,共13页
在梳理总结国内外关于贫困地理与农村多维空间贫困、乡村地域系统与贫困地域系统理论前沿研究的基础上,提出“乡村贫困地域系统”研究视角,并对乡村贫困地域系统理论内涵进行了初步探析.以云南省镇沅县109个村域为评价分析单元,构建了... 在梳理总结国内外关于贫困地理与农村多维空间贫困、乡村地域系统与贫困地域系统理论前沿研究的基础上,提出“乡村贫困地域系统”研究视角,并对乡村贫困地域系统理论内涵进行了初步探析.以云南省镇沅县109个村域为评价分析单元,构建了乡村贫困地域系统演化发展评价指标体系,设计了乡村贫困地域系统演化发展指数测度模型和基于“时空立方体—新兴时空热点分析”的时空演化模式识别方法.研究显示:(1)镇沅县2013-2021年乡村贫困地域系统演化时序阶段性特征经历了“差异波动演化(2013-2015年)—快速演化(2016-2019年)—增长滞缓趋稳(2020-2021年)”3个主要阶段.(2)镇沅县乡村贫困地域系统时空演化模式以连续热点模式为主,加强的热点模式呈零星分布,表征2013-2021年镇沅县乡村贫困地域系统整体上经历了较快且连续稳定的减贫演化过程,是减贫政策普惠作用在时空演化模式上的具体表现;连续冷点模式和持续冷点模式呈现出县域东西两端集聚分布态势.(3)多维空间贫困陷阱主要集中在和平镇、者东镇、振太镇的部分村域,相关村域脱贫稳定性相对较差、返贫风险较高.乡村发展是乡村地域系统循环累积与动态演化的结果,深入刻画分析乡村贫困地域系统时空演化格局与特征,对于科学推动脱贫地区转型发展具有重要意义. 展开更多
关键词 乡村贫困地域系统 时空演化格局 西南山区 镇沅县
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流域视角下安徽省传统村落时空格局差异性研究
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作者 张鲜鲜 何发 +4 位作者 张大鹏 杨灿灿 陈智慧 张婷 黄丹妮 《地域研究与开发》 北大核心 2024年第1期125-132,共8页
选取安徽省内淮河流域和长江流域传统村落为研究对象,从时间和空间两个维度分析传统村落演化差异性并探究影响传统村落分布的主要驱动因子。结果表明:(1)在时间维度,在历史发展进程中传统村落差异明显。淮河流域经历“萌芽期—雏形期—... 选取安徽省内淮河流域和长江流域传统村落为研究对象,从时间和空间两个维度分析传统村落演化差异性并探究影响传统村落分布的主要驱动因子。结果表明:(1)在时间维度,在历史发展进程中传统村落差异明显。淮河流域经历“萌芽期—雏形期—形成期—饱和期—平缓期”,传统村落以农耕生活方式平稳发展。长江流域经历“萌芽期—雏形期—发展期—转变期—鼎盛期”,传统村落以经商生活方式迅速发展;(2)在空间维度,传统村落重心迁移路径均为由北向南,但空间格局特征差异性显著。淮河流域传统村落主要聚集在耕地密集的淮河北岸但聚集度较低,分布聚集度先减小后增加。长江流域传统村落显著聚集在长江南岸,分布聚集度持续增加;(3)两流域内传统村落均主要分布在低海拔、低坡度、邻水系及气候适宜的地区,不同历史时期气温和降水是影响传统村落空间分布的主要驱动因子,长江流域传统村落受高程影响程度高于淮河流域。长江流域内现存传统村落空间分布受地均GDP和人口密度影响程度高于淮河流域内传统村落。 展开更多
关键词 传统村落 空间分析 时空演化 影响因素 地理探测器 安徽省
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