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1.
基于ESDA-GIS的新疆能源碳排放空间差异动态演化分析   总被引:1,自引:1,他引:0  
基于2002-2014年新疆能源碳排放数据,采用Arc GIS9.3,运用标准差椭圆与ESDA相结合的方法深入剖析了新疆能源碳排放空间差异动态演变特征,结果表明:新疆各地、州、市能源碳排放具有显著的空间自相关性;热点和次热点区主要集中分布在北疆地区,且呈现不断缩小的趋势,而次冷点和冷点区域范围则不断扩大;能源碳排放呈现出东北—西南、西北—东南的空间分布格局,标准差椭圆呈现出逐渐向南疆地区移动的趋势,以昌吉地区为核心,范围包括了新疆能源碳排放主体地区,能源碳排放重心呈现东南—东北—东北方向的变动趋势;最后,基于得出的结论提出相应的解决对策,旨在为实现新疆经济、能源、环境的协调发展建言献策。  相似文献   

2.
结合江苏省经济结构和自然环境情况,选择合适的碳排放模型进行核算,得到江苏省各区县的碳排放量,综合DMSP/OLS夜间灯光影像和NDVI数据,再结合人口、GDP和工业生产总值数据,构建碳排放的空间滞后回归模型并开展江苏省碳排放的空间分布模拟,得到大小为1km×1km的碳排放空间格网,并对模拟结果纠正,用以研究江苏省各区县的碳排放量分布情况。结果表明,江苏省碳排放清晰地呈现出"苏南苏北苏中"的格局,苏南地区分布着以苏州、无锡为中心和以南京市区为中心的碳排放高值集聚的"热点"区域;在各区县内部,碳排放的空间分布与人口、GDP产值等密切相关,明显集中于人口、工业聚集的市区和县城区域。  相似文献   

3.
以能源产区陕西省榆林市的12个区县为研究单元,在Geo Da和Arc GIS等软件的支持下,结合趋势分析和空间统计方法,分析2005—2010年榆林县域尺度下的能源消费碳排放强度的空间格局特征与空间分异机制。榆林各区县能源消费碳排放强度水平差异明显,总体差异呈扩大趋势,两极分化加剧。县域碳排放强度南北走向上表现出逐渐减小趋势,东西走向上具有微弱的"U"型变化态势。总体上,东北部区县碳排放强度高于西南部。各区县碳排放强度具有正的空间关联分布特征,且处于低水平非均衡空间分布状态,空间依赖性明显。结合相关性分析,榆林区县碳排放强度具有极化区、扩散区、塌陷区和传染区4个特征。"热点"主要分布在东北部三县,"冷点"主要分布于南部六县。能源资源分布不均、经济总量以及产业结构差异是造成榆林碳排放强度空间分布不均的主要原因。  相似文献   

4.
精确刻画放牧强度时空格局是深刻理解青藏地区高寒草地服务功能动态及其驱动机制的重要基础,对辅助制定区域生态安全和可持续发展战略具有意义。基于牲畜年末存栏量、牧区人口密度、生长季NDVI、年降水量、年平均气温和居民点分布等数据,采用地理加权随机森林模型,模拟了2000年、2010年和2020年3期青藏地区放牧强度的空间格局,并定量评价了环境因子对放牧强度空间分布解释性的区域差异。结果表明:(1)地理加权随机森林模拟结果可精细地刻画青藏地区放牧强度的空间特征,与经典随机森林模型相比,判定系数更高,平均绝对值误差和均方根误差更低。(2)青藏地区放牧强度呈现东南高、西北低的基本特征,其中,西北部地区放牧强度低于25羊单位/km2的区域约占青藏地区面积的1/2。(3)与2000年和2010年相比,2020年青藏地区放牧强度呈现总体下降、局部抬升的态势;其中,较2010年,2020年放牧强度下降超过1羊单位/km2的区域占牧区面积的61.69%。(4)牧区人口密度是解释放牧强度空间异质性最主要的因素,其相对重要性呈现西高东低的特征,而降水量和生长季NDVI...  相似文献   

5.
基于空间杜宾模型的中国高学历人才时空分异研究   总被引:1,自引:0,他引:1  
基于2001~2016年全国统计年鉴数据,采用集聚度分析和空间自相关分析等方法,描绘中国高学历人才的空间格局及变化,并采用空间杜宾模型,探究影响高学历人才空间分布的主要因素及空间溢出效应。结果表明:(1)中国人才分布表现出较大的非均衡性,集聚程度表现为东南高、西北低,且2000~2015年间,人才稀疏区面积下降而集聚区面积上升;(2)中国人才密度的全局莫兰指数为正,表明中国的高学历人才分布具有一定的空间集聚特征,而2000~2015年此指数有所下降,表明人才分布整体上有分散趋势。2000年热点区与次级热点区主要分布于京津冀和长三角地区,其中热点区为京、津、沪;而2015年,热点以及冷点区域均有所扩张,表明局部地区人才仍然有集中化的趋势;(3)工资水平、高校发展、公共服务水平是决定人才空间分布的主要因素,但没有证据表明生活支出比、失业率、房价有显著影响。人才分布具有明显的空间溢出效应,同时工资水平、高校发展、公共服务水平等影响因素也具有明显的空间溢出效应。  相似文献   

6.
基于POI数据的山西省旅游景区分类及空间分布特征   总被引:1,自引:1,他引:0  
郭艳萍  刘敏 《地理科学》2021,41(7):1246-1255
运用大数据与传统地理信息系统相结合的方式,以山西旅游景区POI(Point of Interest)数据为研究对象,对其进行分类后,研究其总体空间分布格局、分布方向以及具体地市空间分布特征。结果表明:山西旅游景区总体分布格局呈现晋中地区集聚特征,具体各类旅游景区的集聚形态与程度有所差异。其中,地文景观类旅游景区集聚于晋中、晋东南和晋北东部地区;水域风光类旅游景区以晋中、晋南和晋北东部地区为轴呈条带状分布;生物景观类旅游景区在空间上呈“菱形”状集聚形态;遗址遗迹类旅游景区集聚于晋北和晋东南地区;建筑与设施类旅游景区呈“三角形”状集聚特征;娱乐购物类旅游景区在全省范围内分布较为均匀。旅游景区空间分布方向与山西省区域形状吻合,除娱乐购物类旅游景区分布方向性和向心性不明显之外,其他类别旅游景区均有不同程度的集聚特征;各地市旅游景区分布情况中,水域风光类旅游景区在各市域间分布较为均匀,地文景观类和建筑设施类旅游景区热点区域出现在阳泉市,冷点区域出现在晋城市,但其集聚程度均较低;生物景观类旅游景区热点区域位于长治市,冷点区域位于临汾市和运城市,其集聚程度较高。最后,从自然地理和人文社会两方面对旅游景区空间分布的影响因素进行了定性分析。  相似文献   

7.
基于2020年1月24日至12月18日我国314个城市的COVID-19现存确诊数、累计确诊数等统计数据,采用地理数据探索、新兴时空热点分析、空间马尔科夫链、动态面板数据空间杜宾模型等方法分析了COVID-19疫情的时空变化特征。研究发现:我国COVID-19疫情大致划分为大规模快速爆发期、全国严格防控期、全国抑制期、局部复发期、常态化防疫期5个阶段,绝大部分城市的疫情变化特征与全国总体情况类似;新兴时空热点方法识别出4种类型共124个疫情冷热点,其中增强热点24个、振荡热点27个、持续冷点16个、渐少的冷点57个;疫情热点主要分布于中东部地区特别是湖北周边区域,疫情冷点主要分布于西南、西北及东北地区;各城市现存确诊人数的马尔科夫链转移概率矩阵分析结果显示,各种类型维持现状的概率大于0. 893,向下转移的平均概率明显高于向上转移的概率,在不同空间滞后类型的影响下各类型转移概率发生明显变化;动态面板空间杜宾模型估计结果显示314个城市现存确诊数具有显著的时空自相关性且不同阶段有明显差异。  相似文献   

8.
基于空间视角,结合中国284个地级及以上城市2011—2019年的面板数据,实证检验了数字经济对旅游发展影响的空间效应及作用机理。结果表明:1)研究期内,数字经济与旅游发展均呈现显著的空间正相关。其中,数字经济的热点区被“空间锁定”于东南沿海地区,而位于中西部的冷点区则大幅收缩;旅游发展的热点区主要分布在长三角城市群和滇桂黔渝,冷点区位于山东半岛中西部并逐步向南延伸。2)中国情境下,数字经济既能助力本地旅游发展,同时存在显著的正向空间溢出效应。从区域异质性看,直接效应虽在各地均显著为正,但在东部地区的作用强度明显大于中西部及东北地区;空间溢出效应在东部得到完全彰显,在中部和东北地区表现为部分显著,西部地区则存在“数字隔离”现象。3)数字经济对旅游发展的正向外溢在300 km处达到最优,此后呈地理距离衰减态势,在800 km处到达有效外溢临界点,1 500 km处达到最大衰减边界。4)数字经济各维度中,数字基础设施、数字产业发展和数字普惠金融均能显著驱动本地旅游发展,但仅数字普惠金融的正向溢出有效突破了行政边界,其余二者均表现出不显著的空间溢出效应。  相似文献   

9.
林建鹏 《地理科学》2022,42(2):284-292
基于机构分层分析框架,运用统计与空间分析方法,剖析中国省域基层医疗卫生机构和医院医疗资源配置与服务利用协调发展的时空演化特征及其驱动因子。研究发现:2010—2018年2类机构的耦合协调类型由濒临失调衰退型变为勉强协调发展型;总体呈东部经济发达地区水平较高,中部地区居中,西北、东北、西南等经济欠发达沿边地区较低的空间分布格局和以长江中下游地区和青藏高原地区为核心的热、冷点区的空间聚集特征,同时在空间格局改善程度、局部空间集聚效应强度和冷热点区变化范围等方面存在差异;受人口分布与结构、经济发展水平和地理空间等因子驱动,同时存在明显时空异质性特征。  相似文献   

10.
江苏省碳排放效率时空格局及驱动因素   总被引:1,自引:0,他引:1  
采用SBM模型、ESDA与GWR等方法,以县域为研究单元,分析2002—2015年江苏碳排放效率空间格局及驱动因素。结果表明:江苏碳排放效率区域差异呈先增后减变化趋势,空间上呈南高北低格局;研究期内江苏碳排放效率的分布呈显著的空间正相关集聚,形成以昆山、南京市区以及无锡市区为核心的三大热点区和以泗阳—宿迁市区—沭阳为中心的冷点区并向外扩散的空间俱乐部;城镇化水平对江苏省碳排放效率空间差异的影响逐步增强,技术创新影响作用逐步凸显,能源消耗强度对碳排放效率空间差异影响程度呈增强趋势。  相似文献   

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BOOK REVIEWS     
Books reviewed in this article: USA, Eine Geographische Landeskunde , Vol. I, Der Grossraum in Strukturellem, Wandel, 3rd Ed. Helmut Blume . Introduction to Remote Sensing . James B. Campbell . The Sounds of People and Places: Readings in the Geography of American Folk and Popular Music . George O. Carney , ED. Development and Underdevelopment . John Cole . Mobility and Employment in Urban Southeast Asia: Example from Indonesia and the Philippines . Michael A. Costello , Thomas R. Leinbach , AND Richard Ulack . Soviet Asia: Economic Development and National Policy Choices . Leslie Dienes . The Third World City . David Drakakis -Smith . Scholars' Guide to Washington, DC for Cartography and Remote Sensing Imagery (maps, charts, aerial photographs, satellite images, cartographic literature and geographic information systems). Ralph E. Ehrenberg . Population and Development in the Third World . Allan AND Anne Findlay . The Early Mapping of Hawaii . Gary L. Fitzpatrick . Energetics of Physical Environment: Energetic Approaches to Physical Geography . K. J. Gregory , ED. Wildland Recreation: Ecology and Management . William E. Hammitt and David N. Cole . Agricultural Commercialization and Government Policy in Africa . J. Hinderink AND J. J. Sterkenburg . The Dynamics of American Housing . James W. Hughes AND George Sternlieb . Thailand: Buddhist Kingdom as Modern Nation State . Charles F. Keyes . Resolving Locational Conflict . Robert W. Lake , ED. Lands at Risk in the Third World: Local-level Perspectives . Peter D. Little and Michael M. Horowitz , EDS. Nathaniel Southgate Shaler and the Culture of American Science . David N. Livingstone . Regions: The Economics and Politics of Territory . Ann R. Markusen . Wetlands . William J. Mitsch and James G. Gosselink . Historical Geography: Progress and Prospect . Michael Pacione , ED. Loess and Periglacial Phenomena . Marton P$eacsi and Hugh M. French , EDS. Regional Management of Metropolitan Floodplains, Experience in the United States and Abroad . Rutherford H. Platt , ED. Human Cartography: Mapping the World of Man . Janos Szegö . Atlas of Great Lakes Indian History . Helen H. Tanner , ED. The Botany of Mangroves . P. B. Tomlinson . Urban Spatial Traffic Patterns . Rodney Vaughan . The Night After … Climatic and Biological Consequences of a Nuclear War . Yevgeni Velikhov , ED. Industrial Geography . H. D. Watts . Dictionary of Quotations in Geography . James O. Wheeler and Francis M. Sibley . Vermont Townscape . Norman Wiliams , Jr. , Edmund K. Kellogg and Peter M. Lavigne .  相似文献   

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A palaeoecological study of an oligotrophic alpine lake, Paione Superiore (Italy), provided a record of historical changes in water quality. Historical trends in lake acidification were reconstructed by means of calibration and regression equations from diatoms, chrysophycean scales and pigment ratios. The historical pH was inferred by using two different diatom calibration data sets, one specific to the alpine region. These pH trends, together with the record of sedimentary carbonaceous particles and chironomid remains, indicate a recent acidification of this low alkalinity lake.Concentration of total organic matter, organic carbon, nitrogen, biogenic silica (BSiO2), chlorophyll derivatives (CD), fucoxanthin, diatom cell concentration and number of chironomid head capsules increased during the last 2–3 decades. When expressed as accumulation rates, most of these parameters tended to decrease from the past century to c. 1950, then all except P increased to the present day. A marked increase in sedimentary nitrogen may be related to atmospheric pollution and to the general increases in output of N in Europe. High C/N ratios indicate a prevailing allochthonous source of organic matter.Finally, the increase in measured air temperature from the mid-1800's appeared to be related to lake water pH before industrialization: cold periods generally led to lower pH and vice-versa. The more recent phenomenon of anthropogenic acidification has apparently decoupled this climatic-water chemistry relationship.  相似文献   

15.
Quinghai Hu is a large, high-altitude, saline lake in north-western China, and supports a fishery based on an endemic species of naked carp (snow trout). The fish take seven years to attain maturity and a marketable weight of 300 g, and have a lifespan of 14–21 years under the present fishery regime. They seasonally migrate from the lake to spawn over the gravel beds of inflowing rivers, but these areas have been reduced by weirs and irrigation diversions and recruitment may have declined. The population may have been affected also by a 1.85-m fall in the lake level over the past 30 years, and by associated changes in salinity. The fishery was opened to large-scale exploitation in 1958. Yields declined sharply (max. 28,523 tonnes, 1960) as the larger, older fish were removed, and then more slowly (min. 2523 tonnes, 1983). Since 1987 the fish factory has been limited to an annual quota of 1200 tonnes, taken by a fleet of four pair trawlers. Another 800 tonnes are taken by licensed fishermen, mainly using gill nets, and perhaps 1000 tonnes are taken illegally. The estimated total catch in 1992 was 3000 tonnes. New trawlers introduced in 1989–90 substantially increased the factory's catch per unit effort, and in 1990 the quota was virtually filled in one month in a zone within 20 km of the factory. Although this could suggest that the stocks will be conserved if the quota is retained, at least half of the catch in 1989–92 consisted of immature individuals. Trawling operations recently were suspended following a further decline in the catch after 1992. While the new trawlers are capable of a major increase in effort, neither the changing environment, the fish stocks or the present markets favour intensified pressure. Gillnets may provide better control over the minimum size limit and may cause less damage than trawling. Other options to improve the viability and profitability of the fishery include improvements in handling, processing and marketing. Failure to develop the fishery may encourage attempts to introduce exotic fish, at some risk to survival of the local species.  相似文献   

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The altitudinal distribution of Chironomidae (Diptera) in the southern Canadian Cordillera was analyzed by means of head capsules preserved in surficial sediments of 30 lakes. Taxa characteristic of late-glacial deposits of southern, coastal British Columbia are extant at high elevations, particularly in the Rocky Mountains, and in large, deep, low-elevation lakes. Many chironomid taxa common at low elevations in the southern Canadian Cordillera were not found in alpine and upper subalpine lakes. These faunal differences are probably climatically related. The differences in fauna between high and low-elevation lakes parallel differences between arctic and temperate lakes.  相似文献   

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ABSTRACT. Narratives concerning Pacific Ocean territories are often historically derived from European and American mainland visions of great, empty oceans dotted with deserted and uninhabited islands. However, research by indigenous and outlander scholars, along with struggles for political and cultural autonomy in the Pacific, has brought attention to vital island communities and 6has raised questions about a Pacific‐island way of understanding the world. This understanding is traced through scholarly and artistic engagements with history, island‐community studies, and navigational philosophies and is framed by a growing theoretical literature on epistemologies of place from the disciplines of geography and oceanography.  相似文献   

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Precipitation is an important component of global water and energy transport and a major aspect of climate change. Due to the scarcity of meteorological observations, the precipitation climate over Tibet has been insufficiently documented. In this study, the distribution of precipitation during the rainy season over Tibet from 1980 to 2013 is described on monthly to annual time scales with meteorological observations. Furthermore, four precipitation products are compared to observations over Tibet. These datasets include products derived from the Asian Precipitation-Highly-Resolved Observational Data(APHRO), the Global Precipitation Climatology Centre(GPCC), the University of Delaware(UDel), and the China Meteorological Administration(CMA). The error, relative error, standard deviation, root-mean-square error, correlations and trends between these products for the same period are analyzed with in situ precipitation during the rainy season from May to September. The results indicate that these datasets can broadly capture the temporal and spatial precipitation distribution over Tibet. The precipitation gradually increases from northwest to southeast. The spatial precipitation in GPCC and CMA are similar and positively correlated to observations. Areas with the largest deviations are located in southwestern Tibet along the Himalayas. The APHRO product underestimates, while the UDel, GPCC, and CMA datasets overestimates precipitation on the basis of monthly and inter-annual variation. The biases in GPCC and CMA are smaller than those in APHRO and UDel with a mean relative error lower than 10% during the same periods. The linear trend of precipitation indicates that the increase in precipitation has accelerated extensively during the last 30 years in most regions of Tibet. The CMA generally achieves the best performance of these four precipitation products. Data uncertainty in Tibet might be caused by the low density of stations, complex topography between the grid points and stations, and the interpolation methods, which can also produce an obvious difference between the gridded data and observations.  相似文献   

20.
Potamids generally live in estuaries, lagoons, and along protected sea shores. However, their ability to colonize intracontinental lakes has been underestimated due to non- or misidentifications. Potamides conicus, the only present lacustrine Potamid currently found in North Africa, belongs to a lagoon-type (thalassoid) malacofauna, dominated by the Cardium Cerastoderma glaucum: this fauna occurs in association with Foraminifera (especially Ammonia beccarii) and Ostracoda (Cyprideis gr. Torosa). Potamids have been found 250 to 900 km from the nearest sea shore: passive dispersal (probably through birds) is the primary dispersal mechanism. Shell morphology and ornamentation can be used to characterize life environment (lacustrine versus marine) but not distance from sea shore. The presence of Potamid-Foraminifera fauna in the fossil record has been interpreted as providing evidence for a sea connection (e.g., gulfs, lagoons). However, more recent paleoecological studies have demonstrated that such assemblages span an ecological gradient from freshwater to hypersaline lacustrine environments. Thus, the occurrence of modern Potamids in lacustrine (in addition to maritime) environments has important implications for Quaternary and Tertiary paleogeographic investigations. Lacustrine Potamids have been recorded from the European Tertiary (France, Spain) and from the Sahara Holocene. More research is required for the better understanding of the distribution and ecology of Potamids in modern and fossil lakes of other continents.This publication is the fifth of a series of papers presented at the Conference on Sedimentary and Paleolimnological Records of Saline Lakes. This Conference was held August 13–16, 1991 at the University of Saskatchewan, Saskatoon, Canada. Dr Evans is serving as Guest Editor.  相似文献   

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