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1.
Identification of water potential areas in arid regions is a crucial element for the enhancement of their water resources and socio-economic development. In fact, water resources system-planning can be used to make various decisions and implement management of water resources policies. The purpose of this study is to identify groundwater storage areas in the high Guir Basin by implementing Geographic Information System(GIS)and Remote Sensing methods. The required data for this study can be summarized into five critical factors: Topography(slope), lithology, rainfall, rock fracture and drainage.These critical factors have been converted by the GIS into thematic maps. For each critical parameter, a coefficient with weight was attributed according to its importance. The map of potential groundwater storage areas is obtained by adding the products(coefficient × weight) of the five parameters. The results show that 50% to 64% of the total area of the High Guir Basin is potentially rich in groundwater, where most of fracture systems are intensely developed. The obtained results are validated with specific yield of the aquifer in the study area. It is noted that there is a strong positive correlation between excellent groundwater potential zones with high flows of water points and it diminishes with low specific yield with poor potential zones.  相似文献   

2.
http://www.sciencedirect.com/science/article/pii/S1674987111001034   总被引:10,自引:0,他引:10  
A comprehensive methodology that integrates Revised Universal Soil Loss Equation(RUSLE) model and Geographic Information System(GIS) techniques was adopted to determine the soil erosion vulnerability of a forested mountainous sub-watershed in Kerala,India.The spatial pattern of annual soil erosion rate was obtained by integrating geo-environmental variables in a raster based GIS method.GIS data layers including,rainfall erosivity(R),soil erodability(K),slope length and steepness(LS),cover management (C) and conservation practice(P) factors were computed to determine their effects on average annual soil loss in the area.The resultant map of annual soil erosion shows a maximum soil loss of 17.73 t h-1 y-1 with a close relation to grass land areas,degraded forests and deciduous forests on the steep side-slopes(with high LS ).The spatial erosion maps generated with RUSLE method and GIS can serve as effective inputs in deriving strategies for land planning and management in the environmentally sensitive mountainous areas.  相似文献   

3.
http://dx.doi.org/10.1016/j.gsf.2015.10.007   总被引:6,自引:0,他引:6  
Soil erosion is a serious problem arising from agricultural intensification,land degradation and other anthropogenic activities.Assessment of soil erosion is useful in planning and conservation works in a watershed or basin.Modelling can provide a quantitative and consistent approach to estimate soil erosion and sediment yield under a wide range of conditions.In the present study,the soil loss model,Revised Universal Soil Loss Equation(RUSLE) integrated with GIS has been used to estimate soil loss in the Nethravathi Basin located in the southwestern part of India.The Nethravathi Basin is a tropical coastal humid area having a drainage area of 3128 km~2 up to the gauging station.The parameters of RUSLE model were estimated using remote sensing data and the erosion probability zones were determined using GIS.The estimated rainfall erosivity,soil erodibility,topographic and crop management factors range from 2948.16 to 4711.4 MJ/mm·ha~(-1)hr~(-1)/year,0.10 to 0.44 t ha~(-1)·MJ~(-1)·mm~(-1),0 to 92,774 and 0 to 0.63 respectively.The results indicate that the estimated total annual potential soil loss of about473,339 t/yr is comparable with the measured sediment of 441,870 t/yr during the water year 2002-2003.The predicted soil erosion rate due to increase in agricultural area is about 14,673.5 t/yr.The probability zone map has been derived by the weighted overlay index method indicate that the major portion of the study area comes under low probability zone and only a small portion comes under high and very high probability zone.The results can certainly aid in implementation of soil management and conservation practices to reduce the soil erosion in the Nethravathi Basin.  相似文献   

4.
GIS支持下的青藏公路沿线高含冰量冻土空间分布模型   总被引:1,自引:0,他引:1  
吴青柏  董献付  刘永智 《冰川冻土》2004,26(Z1):137-141
Relationships among ground ice, Quaternary soil type, vegetation cover, digital terrain model (DTM), permafrost ground temperature and topographic units are applied. Using comprehensive evaluated method and coding interpolation, spatial distribution of ground ice in permafrost regions along Qinghai-Tibetan Highway (QTH) is modeled according to GIS spatial analysis. Comparing with result,model precision can be approached to 81.2 %. Its study precision can satisfy engineering need for a small - scale study  相似文献   

5.
One kind of climatic proxies only can describes the comparative change of temperature or rainfall, but dissolved noble gases in groundwater can be used to date groundwater, calculate temperature and rainfall, and this method can give the exact change value of three parameters in one time. Dissolved noble gases in groundwater has four sources, radioactivity-formed noble gases which are from radioactive decay of some radioactive elements in the aquifers, balance-dissolved noble gases from dissolved air in balance condition in the course of supplying, excess noble gases from excess air for groundwater-air mixing and water table changing during infiltrating, and outer-interfused noble gases from outer interfusing air in open conditions during runoff. Because the contents of radioagenic noble gases in groundwater are correlated to flowing time, such as He, the age of groundwater can be dated with 4He based on the solubility of He and the radioactive intensity of aquifers. The solubility of noble gases is the function of temperature. We can compare the contents of balance-dissolved noble gases in groundwater with the temperature-solubility experimental curves of noble gases, and calculate the forming temperature of groundwater. The contents of excess noble gases are related to the water column of infiltration which can reveal the volume of rainfall in a given period of time in general, and it may increase along with the pressure of aquifers when groundwater table rises greatly. So we can calculate the value of rainfall by comparing the contents of excess noble gases in groundwater samples with those in modem groundwater. Reconstruction of climatic change on a quantitative basis with the method of dissolved noble gases in Hebei plain (China) shows that the temperature changed from 3.8 to 19.7℃ in the past forty thousand years, it decreased to 3.8℃ in 16000 a B.P. but higher than 19.7℃ in 5060 a B.P. The rainfall was about 600mm during 40000 to 15000 a B.P., then decreased gradually to 410mm in 11000 a B.P., but subsequently increased to 950mm in 4400 a B.P. The change of noble gas temperature is consistent with 180 shift, and 6D varied with the change of other climatic proxy, such as rainfall.  相似文献   

6.
Modeling landscape with high-resolution digital elevation model (DEM) in a geographic information system can provide essential morphological and structural information for modeling surface processes such as geomorphologic process and water systems. This paper introduces several DEM-based spatial analysis processes applied to characterize spatial distribution and their interactions of ground and surface water systems in the Greater Toronto Area (GTA), Canada. The stream networks and drainage basin systems were derived from the DEM with 30 m resolution and the regularities of the surface stream and drainage patterns were modeled from a statistical/multifractal point of view. Together with the elevation and slope of topography, other attributes defmed from modeling the stream system, and drainage networks were used to associate geological, hydrological and topographical features to water flow in river systems and the spatial locations of artesian aquifers in the study area. Stream flow data derived from daily flow measurements recorded at river gauging stations for multi-year period were decomposed into “drainage-area dependent“ and “drainage-area independent“ flow components by two-step “frequency“ and “spatial“ analysis processes. The latter component was further demonstrated to relate most likely to the ground water discharge. An independent analysis was conducted to model the distribution of aquifers with information derived from the records of water wells. The focus was given on quantification of the likelihood of ground water discharge to river and ponds through flowing wells, springs and seepages. It has been shown that the Oak Ridges Moraine (ORM) is a unique glacial deposit that serves as a recharge layer and that the aquifers in the ORM underlain by Hilton Tills and later deposits exposed near the steep slope zone of the ridges of ORM provide significant discharge to the surface water systems (river flow and ponds) through flowing wells, springs and seepages. Various statistics (cross- and auto-correlation coefficients, fractal R/S exponent) were used in conjunction with GIS to demonstrate the influence of land types, topography and geometry of drainage basins on short- and long-term persistence of river flows as well as responding time to precipitation events. The current study has provided not only insight in understanding the interaction of water systems in the GTA, but also a base for further establishment of an on-line GIS system for predicting spatial-temporal changes of river flow and groundwater level in the GTA.  相似文献   

7.
Landslides are one of the most common and a destructive natural hazard in mountainous terrain and thus evaluating their potential locations and the conditions under which they may occur is crucial for their hazard assessment.Shallow landslide occurrence in soil and regolith covered slopes are often modeled using the infinite slope model,which characterizes the slope stability in terms of a factor of safety(FS) value.Different approaches have been followed to also assess and propagate uncertainty through such models.Haneberg(2004) introduced the use of the First Order Second Moment(FOSM) method to propagate input uncertainty through the infinite slope model,further developing the model and implementing it in the PISA-m software package(Haneberg,2007).Here we present an ArcPy implementation of PISA-m algorithms,which can be run from ESRI ArcMap in an entirely consistent georeferenced framework,and which we call "GIS Tool for Infinite Slope Stability Analysis"(GIS-TISSA).Users can select between different input options,e.g.,following a similar input style as for PISA-m,i.e., using an ASCII.csv parameters input file,or providing each input parameter as a raster or constant value,through the program graphic user interface.Analysis outputs can include FS mean and standard deviation estimates,the probability of failure(FS <1), and a reliability index(RI) calculation for FS.Following the same seismic analysis approach as in PISA-m, the Newmark acceleration can also be done,for which raster files of the mean,standard deviation,probability of exceedance,and RI are also generated.Verification of the code is done by replicating the results obtained with the PISA-m code for different input options,within a 10-5 relative error.Monte Carlo modeling is also applied to validate GIS-TISSA outputs,showing a good overall correspondence.A case study was performed for Kannur district,Kerala,India,where an extensive landslide databa se for the year 2018 was available.81.19% of the actual landslides fell in zones identified by the model as unstable.GIS-TISSA provides a user-friendly interface,particularly for those users familiar with ESRI ArcMap,that is fully embedded in a GIS framework and which can then be used for further analysis without having to change software platforms and do data conversions.The ArcPy toolbox is provided as a.pyt file as an appendix as well as hosted at the weblink:https://pages.mtu.edu/~toommen/GeoHazard.html.  相似文献   

8.
The traditional method for sulfur isotope measurement using EA-IRMS commonly requires sulfur content greater than 2 μmol. Such a large sample size limits its application to low-S materials, the size mainly being due to ineffective utilization of sample gas, almost 99.7% of which is discarded with carrier gas through the split port of the continuous-flow interface. A modified EA-IRMS system with a gas chromatographic (GC) column and a custom-built cryogenic concentration device is used in this study. We measured six reference materials to test the performance of this method. The results were consistent with those obtained through traditional EA-IRMS. Precisions ranging from ±0.24‰ to ±0.76‰ (1σ) can be obtained with samples equivalent to ~80 nmol sulfur, which were similar to results obtained from an alternative method using an absorption column. Our improved method is a powerful tool for sulfur isotope measurement in ultrasmall sulfide and sulfate samples, which can be further applied to carbon, nitrogen and oxygen isotope analyses of samples at about 100 nmol level.  相似文献   

9.
Compositional peculiarities of the siliceous high-Mg series(SHMS)rocks formed at the Archean-Paleoproterozoic boundary as a function of plume activity are discussed using example of Early Paleoproterozoic mafic volcanic rocks of the Vodlozero Domain,Fennoscandian Shield.These rocks are characterized by wide variations in Mg#(33-67)and Cr contents(25-1123 ppm),LREE enrichment,and weakly negative_(εNd)(from-0.7 to-2.9).The high Gd/Yb ratio in the primitive high-Mg rocks of the Vodlozero Domain suggests their generation from a garnet-bearing source.At the same time,their negative _(εNd)in combination with LREE enrichment points to the crustal contamination.A new model was proposed to explain the remarkable global-scale similarity of SHMS.Such rocks can be generated by the contamination of a high-degree(30%)partial melt derived from a depleted mantle.The lower crustal sanukitoid-type rocks can be considered as a universal crustal contaminant.Modeling showed that such mixing can provide the observed narrow_(εNd)variations in Early Paleoproterozoic volcanics.The Neoarchean sanukitoid suites,which are widespread on all cratons,presumably composed the lower crust at the beginning of the Paleoproterozoic.Therefore,this mechanism can be considered universal for the genesis of the SHMS rocks.The high-to low-Cr rock series can be produced by the fractionation of the mafic melt coupled with an insignificant crustal assimilation of felsic end members of the sanukitoid suite of the Vodlozero Domain en route to the surface,as suggested by the positive correlation of_(εNd)with Cr and Mg#,negative correlation with Th,and slight decrease of_(εNd)in the more evolved varieties.  相似文献   

10.
Cadmium has been determined by β-correction spectrophotometry with cadion,p-nitrobenzenediazoaminoaz-obenzone,and a non-ionic surfactant,tuiton X-100.The real absorbance of a Cd-cadion chelate in the colored solution can be accurately determined and the complex-ratio of cadion with Cd(II) has been worked out to be 2.Beer‘s law is obeyed over the concentration range of 0-0.20mg/1 cadmium and the detec-tion limit for cadmium is only 0.003mg/1.Satisfactory experimental results are presented with respect to the determination of trace cadmium in wastewaters.  相似文献   

11.
全国重要成矿区带基础数据库服务体系分为技术服务和数据服务两大部分.在技术服务层面上,根据全国重要成矿区带基础数据的特点,划分了数据裁剪类型;利用2个长二进制字段分别存储图元信息和拓扑信息,解决了空间数据装入数据库中易造成数据丢失和格式转换信息缺失的难题;利用关系数据库和空间数据引擎解决了属性数据和空间数据一体化存储和联合查询难题.在数据服务层面上,指出采用WebGIS在线服务、目录服务和解说服务以及光盘邮寄服务相互结合、互相补充的方式,既可以很好地满足用户需求,又能保证数据的安全;并划分了数据类型和用户级别;提出了保护数据安全的策略.  相似文献   

12.
二调中MapGIS数据到ArcGIS数据转换问题的研究   总被引:1,自引:0,他引:1  
葛琴 《安徽地质》2012,(3):223-225
目前,应用比较广泛的两种地理信息系统软件MapGIS软件和ArcGIS软件,都各自占有很大的地理信息市场.但它们的各自都拥有自己的数据格式.一直以来地矿部门所采用GIS软件基本上是MapGIS软件,随着ArcGIS软件在我国各领域应用逐渐广泛,这就需要我们将目前拥有的大量MapGIS格式的GIS数据转换成ArcGIS数据.因此在资源有效利用驱使下,迫切需要实现这两种数据格式的共享.本文深入讨论了实现GIS软件之间数据格式转换的各种方法,并描述了由MapGIS格式数据转换为ArcGIS格式数据的详细过程.通过转换过程分析这种转换模式存在的问题,并提出解决问题的方法.  相似文献   

13.
辽宁省矿产资源储量空间数据库系统建设的探讨   总被引:2,自引:2,他引:2  
论述了建立基于MapGIS和Micromine软件平台,实现辽宁省矿区储量分布的可视化和建立矿床空间模型的思路、方法.该数据库系统与现有的探矿权、采矿权数据库及规划数据库实现互联互通,能够充分发挥储量数据信息的基础性作用,提高矿产资源储量管理工作水平和效率,为四级矿政管理和矿产资源信息的社会化服务提供有效的技术手段.  相似文献   

14.
朱世勇 《福建地质》2014,(3):214-225
以我国矿业权实地核查数据为例,讨论AutoCAD、MapGIS、ArcGIS3种数据格式转换软件集成开发设计思路,详细剖析数据格式的特点,对建立三者间空间结构、属性、渲染关系的特性分析研究,提出其空间数据跨平台无损转换的整体解决技术方案,开发系统可实现自动批量无损转换,支持统一标准化图件模板定制。  相似文献   

15.
大数据是海量、高增长率和多样化的信息资产,是未来找矿靶区预测的不可或缺的技术。大数据-三维成矿预测研究面临机遇与挑战,其涉及的地学大数据除了数据来源众多、比例尺不同、数据量大、非结构化管理、时效性强、空间数据与非空间数据协同管理等复杂特点外,还必须具有适应进行三维建模及空间分析的数据结构。本文分析了地学空间大数据的特点,对多源地学综合信息的管理需求进行研究,参考国家及行业标准,建立了可满足三维成矿预测需求的多源地学空间数据库模型,并依据实际划分为勘查控制钻孔地质数据库、空间属性数据库和地球物理数据库,各数据库可在多源地学空间索引库的支持下协同工作。本文以大数据应用的典型实例--钟姑矿田作为研究对象,系统收集了矿田内勘查成果资料,建立了钟姑矿田多源地学空间数据库,并在此基础上进行了控矿要素的有效提取,可进一步支持三维成矿预测。研究结果表明,本文提出的多源地学空间数据库可有效管理地学空间大数据,是大数据-三维成矿预测的重要解决方案,是进行三维成矿预测的重要数据支持。  相似文献   

16.
地质图空间数据库数据量大, 内容复杂, 为了保证数据库的质量, 在地质图空间数据库的建立过程中, 对数据的全面系统检查工作是非常必要的。对于地质图空间数据库, 检查属性数据库的内容以及属性数据与空间图形数据的正确链接是难点之一, 也是一项最耗时的工作。为了科学、快速地检查地质图属性数据, 保证属性内容的正确性以及非空间数据与空间数据的正确对应, 针对这一问题, 在进行全国1:100万地质图空间数据库的检查时, 设计开发了属性数据库的自动检查系统。本文以近期完成的全国1:100万地质图空间数据库的检查系统设计研究为例, 主要介绍了地质图数据库属性数据自动检查系统的设计开发, 其中详细介绍了各模块可以实现的主要功能。通过此项检查, 能够提高入库数据的质量, 为数据库后期的应用与共享提供可靠保障, 从而为地质科学研究、矿产勘查及生态环境治理等提供科学的地质图数据资料。  相似文献   

17.
金属矿床勘查找矿信息系统的设计与实现   总被引:1,自引:0,他引:1  
从金属矿床勘查找矿和国土资源信息化建设的实际出发,通过科学合理的筛选、归纳,总结出金属矿床勘查找矿信息,进而提出系统设计方案,包括信息采集子系统(客户端)、信息检索子系统(客户端)和网络数据库服务(服务器端)等3个子系统,以及属性信息采集模块、空间信息采集模块、基础数据采集模块、数据维护模块、属性信息检索模块、空间信息检索模块和基础数据检索模块7个主要模块。采用VB MapGIS组件 SQLServer的集成开发模式,开发了具有友好人机接口,能够为地质勘查单位、政府管理部门和公众提供服务的金属矿床勘查找矿信息平台。同时,给出了项目开发过程中解决的部分技术问题的VB程序代码。  相似文献   

18.
中国地下水资源空间数据库标准化研究   总被引:3,自引:0,他引:3       下载免费PDF全文
结合新一轮全国地下水资源评价工作的实际情况,对评价工作涉及到的数据信息进行了综合分析,建立了数据的层次结构模型,进而提出了空间数据库图层的划分方案,结合Ma pGIS软件系统的数据格式给出了空间数据库的图层与属性的存储结构,并探讨了与空间数据库相关的数字制图等技术问题.  相似文献   

19.
全国1:200 000数字地质图空间数据库是基于目前中国唯一的、实测的、全国性的1:200 000区域地质调查成果,由全国多家单位共同完成的全国性基础地质学空间数据库之一。数据库在空间上包含1 163幅1:200 000地质图数据,覆盖整个国土范围的72%,包含MapGIS和ArcGIS两种格式,总数据量达到90 GB。数据库主要资料来源于1:200 000区域地质调查报告和地质图及矿产图,原始资料时间跨度从20世纪50年代中期到90年代初期。全国1:200 000数字地质图(公开版)空间数据库通过国家级验收,数据完整性、逻辑一致性、位置精度、属性精度、接缝精度均符合中国地质调查局制定的有关技术规定和标准的要求,质量优良可靠。全国1:200 000数字地质图空间数据库是国家空间数据的重要组成部分,为国民经济信息化提供数字化空间平台,为国家和省级各部门进行区域规划、地质灾害监测、地质调查、找矿勘查、宏观决策等提供信息服务。  相似文献   

20.
大千世界万物众生,具有物以类聚、人以群分的客观规律,因而促使对客观对象的科学研究皆可采用分门别类的方法去进行,这一理念同样可以延伸到地图制图及地理信息系统等以地物、地图为研究对象的学科中。由此衍生的数据分层是地理信息系统的关键词之一,科学有效的数据分层,是数据管理、GIS地图编制、制图综合、专题制图、空间分析的前提,国内、外著名的CAD、GIS软件都充分利用了层概念和其技术。在讨论层概念的基础上,利用两个在地学界应用比较广泛的和著名的GIS软件即我国具有自主版权的MapGIS和来自美国的ArcGIS,仔细研究和分析了层概念在软件中的应用;经研究进一步表明,数据分层是GIS技术得以进行空间数据管理、表达及进行空间分析的基础;在此基础上,对主题层、数据层、图层进行了概念上的界定,以此帮助对GIS技术的理解和应用。  相似文献   

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