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1.
潜流带(即地表水-地下水交互作用带)是位于地表水和地下水之间发生物质和能量交换的,具有物理、化学、生物梯度的饱和含水带。潜流带内发生着强烈的生物地球化学过程,在改善水环境质量和维持水生态系统稳定中发挥着重要作用。潜流带生物地球化学特征主要受河床沉积物结构特征、水文特征、环境特征、生物群落格局、物质输入等因素的影响,潜流带内C、N、P元素以及有毒金属元素(Fe、Mn、As、Hg等)会发生氧化-还原、吸附与解吸、沉淀与溶解、生物催化等生物地球化学过程。原位监测、数值模拟、原位培养和地球物理探测等技术是潜流带中生物地球化学过程研究中常用的研究手段。未来针对潜流带的研究可以从监测和数值模拟技术、河床沉积物变化特征以及微生物生态系统的结构和功能等方面进一步开展。  相似文献   

2.
20世纪90年代中国东西部土地利用变化时空特征分析   总被引:2,自引:2,他引:0  
在覆盖全国的1km栅格土地利用本底与动态成分数据时空信息平台支持下,应用土地利用动态度模型,分别计算了全国及东西部地区土地利用一级类型的单一和综合动态度,并分析了土地利用动态度的空间格局。通过分析东西部土地利用类型变化特征和土地利用类型转换特征,对20世纪90年代中国东西部土地利用变化过程的时空特征进行了全面分析,揭示了东西部地区土地利用变化的时空规律。并对主要土地利用类型变化的原因进行了分析。  相似文献   

3.
视频GIS技术可以融合视频处理技术与GIS分析技术实现视频场景的公共安全监控,在公共场所视频监控应用领域,人群密度和数量能够反映地理空间场景的人群拥挤程度,具有一定的公共安全风险控制作用。为满足公共安全领域利用视频GIS技术对视频人群监测及分析的需求,提出了一种视频前景多特征融合的人群密度及数量估计方法。该方法融合前景图像块的边缘纹理特征,通过SVM区分场景人群密度,然后以归一化前景面积、轮廓和边缘纹理特征作为回归因子,根据人群密度差异分类构建回归模型,进而估算场景人群数量。实验结果表明,此方法能够高效估计视频场景的人群密度和数量,准确表征该场景人群分布状态。  相似文献   

4.
Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. Supported by the dynamic serving system of national resources, including both the environment database and GIS technology, this paper analyzed the land-use change in northeastern China in the past ten years (1990–2000). It divides northeastern China into five land-use zones based on the dynamic degree (DD) of land-use: woodland/grassland — arable land conversion zone, dry land — paddy field conversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamation and abandoned zone. In the past ten years, land-use change of northeastern China can be generalized as follows: increase of cropland area was obvious, paddy field and dry land increased by 74.9 and 276.0 thousand ha respectively; urban area expanded rapidly, area of town and rural residence increased by 76.8 thousand ha; area of forest and grassland decreased sharply with the amount of 1399.0 and 1521.3 thousand ha respectively; area of water body and unused land increased by 148.4 and 513.9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns of land use, this paper also discusses the driving forces in each land-use dynamic zones. The study shows that some key biophysical factors affect conspicuously the conversion of different land-use types. In this paper, the relationships between land-use conversion and DEM, accumulated temperature (⩾10°C) and precipitation were analysed and represented. We conclude that the land-use changes in northeast China resulted from the change of macro social and economic factors and local physical elements. Rapid population growth and management changes, in some sense, can explain the shaping of woodland/grassland — cropland conversion zone. The conversion from dry land to paddy field in the dry land — paddy field conversion zone, apart from the physical elements change promoting the expansion of paddy field, results from two reasons: one is that the implementation of market-economy in China has given farmers the right to decide what they plant and how they plant their crops, the other factor is originated partially from the change of dietary habit with the social and economic development. The conversion from paddy field to dry land is caused prmarily by the shortfall of irrigation water, which in turn is caused by poor water allocation management by local governments. The shaping of the reclamation and abandoned zone is partially due to the lack of environment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relatively higher profits of farming than that of pasturing in the interlocked zone of farming and pasturing. In northeastern China, the rapid expansion of built-up areas results from two factors: the first is its small number of towns; the second comes from the huge potential for expansion of existing towns and cities. It is noticeable that urban expansion in the northeastern China is characterized by gentle topographic relief and low population density. Physiognomy, transportation and economy exert great influences on the urban expansion. Foundation item: Under the auspices of Knowledge Innovation program Key Project of the Chinese Academy of Sciences (KZCX-2-308). Biography: LIU Ji-yuan (1947 - ), male, a native of Shanghai Municipality, professor, Director General of Institute of Geographical Sciences and Natural Resources Research, the Chinese Academy of Sciences. His research interests include environment and resources, remote sensing and geography.  相似文献   

5.
湖北神农架地区南华系大塘坡组属于间冰期沉积,目前对其沉积地层及古环境等方面的认识有限。在神农架地区南华系大塘坡组野外调查的基础上,利用元素地球化学分析测试资料,系统研究了该地区大塘坡组古环境特征及其对油气勘探的意义。CaO/(CaO+Fe)、Sr/Ba、Rb/K、K/Na值表明神农架地区大塘坡组沉积水体盐度整体为中—低盐度,其中大九湖剖面沉积水体盐度比宋洛剖面沉积水体高。氧化-还原性敏感元素相关参数V/(V+Ni)、Ni/Co、Ceanom值研究表明,神农架地区南华系大塘坡组沉积于弱氧化—弱还原水体。CIA、ICV、Sr/Cu、Sr/Ba、Rb/Sr、Mg/Ca值和Sr含量等研究表明,神农架地区大塘坡组沉积期属于温暖湿润气候环境。总有机碳(TOC)、古生物资料以及Cu和Ba含量综合分析表明神农架地区大塘坡组沉积期温暖湿润气候以及合适的水体条件,为藻类的大量繁殖提供了优越的环境,并为大塘坡组优质烃源岩的发育提供了充足的有机质来源。  相似文献   

6.
采样测定了湖南澧水下游表层沉积物21个样品的稀土元素地球化学含量,分析了稀土元素组成特征,据此探讨其物质来源。结果表明:澧水下游表层沉积物中稀土元素总含量为(109.12~192.27)×10-6,平均为148.37×10-6;与湖南土壤背景值相比较,澧水下游表层沉积物含量处于略偏低水平;21个样品的稀土元素含量变化规律高度一致,组成特征变化较小;稀土元素组成表现为轻稀土元素相对富集而重稀土元素相对亏损,Eu呈中等程度亏损,Ce呈弱的负异常;澧水下游表层沉积物的稀土元素总含量、特征参数,与湖南土壤、长江沉积物背景值比较接近,其大陆上地壳标准化和球粒陨石标准化稀土元素配分模式与长江沉积物很接近,这可能暗示了澧水下游表层沉积物除了主要来源于澧水河流侵蚀搬运物外,部分可能来源于松滋口、太平口和藕池口等荆江3口泄洪带入的长江沉积物。  相似文献   

7.
土地利用动态变化的空间测算模型研究   总被引:8,自引:0,他引:8  
本文以GIS叠置分析为辅助手段,将研究区域(广州市海珠区)的土地细分出未变化部分、转移部分和新增部分等三种空间类型,并据此对现有测算土地利用变化速率的数量分析和动态度模型进行了评析,提出了修正后的空间信息测算分析模型,旨在更为精细和准确地测算各土地利用类型的动态变化程度。或者更具体地说这种模型最主要是从微观角度的空间区位上认识不同用地类型变化的面积和速度(增加或减少)的情况,并且要清楚知道变化的用地在空间的分布和时空规律。结合社会经济情况来探讨这种情况发生的原因及其可能产生的结果。该研究对沿海发达地区未来城市土地利用的合理规划有一定的借鉴意义。  相似文献   

8.
This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River watershed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small regional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ...  相似文献   

9.
A new technique designed to help quantify the degree of damage to the landscape from one area to another shows a close relationship between population density and the degree of landscape damage. The technique establishes a scale of damage from 0 to 5 (zero=no damage; 5=severe damage) using data from aerial photographs, land-use maps, and field data. The related formula allows one to compare the relative degree of damage across regions using a combination of an absolute index, a theoretical index, a relative index, and population density. Xing an County is used to demonstrate the technique.  相似文献   

10.
A new technique designed to help quantify the degree of damage to the landscape from one area to another shows a close relationship between population density and the degree of landscape damage. The technique establishes a scale of damage from 0 to 5 (zero = no damage; 5 = severe damage) using data from aerial photographs, land-use maps, and field data. The related formula allows one to compare the relative degree of damage across regions using a combination of an absolute index, a theoretical index, a relative index, and population density. Xing'an County is used to demonstrate the technique.  相似文献   

11.
This paper describes a GIS-based spatial analysis method that combines qualitative analysis and quantita-tive analysis to characterize land-use patterns and predict the trend of future land-use changes in Halzhu District ofGuangzhou City, China. Spatial technique is introduced to manage land-use data and derive information of land-usechanges. Through the case study for the selected area, it is demonstrated that the method and technique introduced in thepaper can be effectively utilized for the analysis of urban land-use changes. Based upon this analysis, the paper also pro-vides discussions and recommendation on urban land-use planning, urban planning and land management. Both land-usemaps of Haizhu District of Guangzhou in 1995 and 1997 and the remote sensing images of 1999 are utilized in the cur-rent research. It is convenient to get various statistic data and to combine attribute data with spatial data so as to analyzeland-use changes in a geographic context, which is especially suitable for the need of urban construction department, ur-ban management department and urban planning department.  相似文献   

12.
《山东国土资源》是国内外公开发行的,以报道最新地质调查及矿产勘查的地学类期刊.该文根据万方数据提供的历年期刊引证数据,科技期刊的评价方法及基本计量指标,对《山东国土资源》的期刊现状进行了分析与评价,认为期刊应建立健全符合实际的审稿流程,建立健全专家库制度,捕捉地学热点,并与科研人员保持深入有效的联系.  相似文献   

13.
中国土地利用时空数据平台建设及其支持下的相关研究   总被引:35,自引:3,他引:32  
20世纪 90年代中期 ,我们建立了国家资源环境动态信息服务运行系统。在土地利用数据库的建设过程中 ,其中 5 2 0 L andsat TM遥感影像经过地理配准和几何校正后 ,在全数字解译环境下 ,解译并绘制了 1∶ 10万的土地利用图。现已将其矢量数据转换为 1km的栅格数据 (包括所有高分辨率的、通过计算每个网格内各土地利用类型的面积百分比而获得的土地利用信息)。因此 ,国家资源环境动态服务系统可用来监测国家尺度的土地利用的变化。  相似文献   

14.
东天山图拉尔根镁铁—超镁铁质岩体主要包含角闪橄榄岩相、辉石橄榄岩相和辉长岩相,辉石为各岩相主要造岩矿物之一。采用电子探针和LA-ICPMS技术对不同岩相中辉石的主量、微量元素进行测试分析,以探讨岩体的性质、来源和演化过程。东天山图拉尔根镁铁—超镁铁质岩体中斜方辉石属古铜辉石,而单斜辉石则为透辉石和顽透辉石。辉石温压计算表明其结晶温度为978℃~1059℃,结晶压力主要为0.71~4.80kbar。岩体母岩浆为亚碱性拉斑玄武质岩浆,是被俯冲板片交代过的亏损地幔发生13%~20%部分熔融的产物。岩体内不同岩相中辉石的化学成分变化较小,表明岩体的结晶分异程度较低,其中辉长岩相的结晶程度较角闪橄榄岩相和辉石橄榄岩相略高;岩浆上侵过程中,角闪橄榄岩相和辉石橄榄岩相受到富硅地壳物质的混染,而辉长岩相受到富铝围岩的混染。结晶分异作用和富硅地壳的混染是引起图拉尔根岩体硫饱和及硫化物熔离的重要因素。  相似文献   

15.
Resources and environment carrying capacity is central to not only regional sustainable development but also major function-oriented zoning. This paper presents an evaluation index system for resources and environment carrying capacity based on four aspects of carrying capacity(i.e., water resources, land resources, the environment, and ecosystems) by using a square deviation decision-making method, and on the basis of above effort evaluates the resources and environment carrying capacity across 31 provincial regions in China(not including Hong Kong, Macau and Taiwan regions of China). In addition, this paper evaluates the current state of socio-economic development, and analyzes the spatial distribution of resources and environment pressure. The results showed that distinct spatial differences in resources and environment carrying capacity and pressure across provincial regions. Resources and environment pressure is affected by both comprehensive resources and environment carrying capacity and socio-economic development. Regions subjected to lower degrees of resources and environment pressure will be restricted by resources and environmental problems through future courses of development owing to excessively low carrying capacities. By contrast, regions with higher comprehensive resources and environment carrying capacity will be subjected to excessively high levels of resources and environment pressure because of rapid socio-economic development. Both of resources and environment carrying capacity and pressure must therefore be considered in the allocation of country-binding targets to provincial regions.  相似文献   

16.
As the members of Chinese Group of the international cooperative project of "Mineral Resources, Metallogenesis,and Tectonics of Northeast Asia", the authors had the opportunity to review the recent achievement of regional geology in this area. This paper is confined to a brief discussion of the nature, composition and evolution of terranes in a part of Northeast China. Nine terranes were recognized. A splicing pattern of when and how the amalgamation of 9 terranes into one microcontient is proposed here.  相似文献   

17.
《山东国土资源》是由山东省国土资源厅主管,山东省地质科学研究院主办的一个省级科技期刊,是山东地学工作者相互学习、交流的平台,在省内外学术界已经具有了一定的影响。该文概述了《山东国土资源》的发展历程,分析了期刊定位,认为期刊应立足特色,优化采编系统,完善审稿流程,提高编辑素养,促进稿源的多样化,才能更好地为地学工作者服务。  相似文献   

18.
Resources potential assessment is one of the fields in geosciences,which is able to take great advantage of GIS technology as a substitution of traditional working methods.The gold resources potential in the eastern Kunlun Mountains,Qinghai Province,China was assessed by combining weights-of-evidence model with GIS spatial analysis technique.All the data sets used in this paper were derived from an established multi-source geological spatial database,which contains geological,geophysical,geochemical and rem...  相似文献   

19.
菏泽市MapGIS土地利用数据库的建设   总被引:1,自引:1,他引:0       下载免费PDF全文
MapGIS土地利用数据库相对基于AutoCAD平台开发的软件有很多优点,该文介绍了菏泽市MapGIS土地利用数据库的建库流程、存在的问题及纠正办法,为建立“数字菏泽”和今后城乡土地变更调查形成一套图数实地相一致的成果创造了条件,提高了土地资源管理的现代化水平。  相似文献   

20.
对地理环境决定论是“资产阶级地理思想”提出质疑。并对人与自然关系进行系统梳理和反思:(1)地理环境决定论产生并发展于东西方两个伟大时代;(2)地理环境决定论在近代受到的批判是误解所致;(3)地理环境决定论大大丰富了历史唯物主义。提出地理环境决定论是人类优秀文化遗产。  相似文献   

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