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1.
人口地图编制方法新探   总被引:1,自引:0,他引:1  
马永立 《地理科学》1997,7(4):342-345
人口地图的编制应针对不同地域的人口分布特征,确定相应的制图单元和表示方法,并拟定相应的人口资料搜集途径和方法。常州市人口图的编制实践说明,城市人口图以多边形的人口密集小区为制图单元,运用多边形分级比值法较为理想。  相似文献   

2.
刘胤汉 《地理研究》1987,6(4):45-53
通过陕北黄土高原土地类型系列图的编制,本文讨论上地类型系列图的制图对象与特点,制图程序与方法,并指出土地类型系列图的特性,制图的理论基础和原则。  相似文献   

3.
本文从制图目的、任务、制图选题和内容,系列制图内容的统一协调,基础地理底图的编制及工作方法步骤等方面,较全面地总结了周口地区第二次县级土壤普查的制图经验,为全区系列成果地图的编制提供了依据,也可供有关方面制图参考。  相似文献   

4.
通过对永夏矿区近2000km2面积土壤中Cu、Zn、Pb、Cd、Ni、Cr、As、Hg和F九种元素的监测,应用数理统计的方法进行数据处理,得出土壤中这些元素的自然背景值;对土壤环境质量评价方法进行了探讨,提出了以土壤背景值和标准差变化进行土壤污染分级的新的分级标准方法,并对永夏矿区土壤环境质量进行了评价。  相似文献   

5.
通过对永夏矿区近2000km^2面积土壤中Cu、Zn、Pb、Cd、Ni、Cr、As、Hg和F九种元素的监测,应用数理统计的方法进行数据处理,得出土壤中这些元素的自然背景值;对土壤环境质量评价方法进行了探讨,提出了以土壤背景值和标准差变化进行土壤污染分级的新的分级标准方法,并对永夏矿区土壤环境质量进行了评价。  相似文献   

6.
我国是世界上地图出现最早的国家之一.历代有过一些著名的地图学家和不少重要的地图作品,在世界地图学史上占有重要地位.只是到了近代才比西方国家落后.新中国成立后我国地图学有了很大的发展.首先建立了国家基本地形图系统,并完成全国1:5万和1:10万航测地形图,编制出版了一批全国和省、县普通地图.在地质、地貌、气候、水文、土壤、植被、农业,环境、海洋等专题制图方面取得很大的成绩,编制了相当数量中小比例尺专题地图和全国与省区地图集.在地图投影、制图综合、专题制图、综合制图等理论研究方面已取得一批成果.近十年开展的计算机辅助制图与遥感制图迅速发展,已局部应用于专题地图编制.  相似文献   

7.
前言 1963年春,我们结合县农业规划工作需要,曾进行县农业地图的编制试验,编制了一套中山县农业地图,其中包括农业土地类型、咸洪涝旱地区分布及土壤分布等图,以供该县农业规划工作的参考。 1964年夏,笔者继续开展番禺县农业地图的编制工作。该县农业局亦提出编制农业土地类型图的要求。他们认为通过土地类型的划分与制图,可以了解各类型土地的特点、分布规律及对农业生产的有利与不利因素,这是进行农业规划工作的重要依据。事实上,  相似文献   

8.
前言 1963年春,我们结合县农业规划工作需要,曾进行县农业地图的编制试验,编制了一套中山县农业地图,其中包括农业土地类型、咸洪涝旱地区分布及土壤分布等图,以供该县农业规划工作的参考。 1964年夏,笔者继续开展番禺县农业地图的编制工作。该县农业局亦提出编制农业土地类型图的要求。他们认为通过土地类型的划分与制图,可以了解各类型土地的特点、分布规律及对农业生产的有利与不利因素,这是进行农业规划工作的重要依据。事实上,  相似文献   

9.
《中国人口地图集》的编制特点   总被引:1,自引:0,他引:1  
本文叙述了《中国人口地图集》的编制特点。图集主要使用了准确的详细的1982年第三次人口普查资料,并用计算机制图技术完成了人口数据的提取、处理、人口指标值计算、统计分析、制图分级和图形输出。在文中同时对图集的自动编制过程作了简要说明。  相似文献   

10.
根据中国土壤系统分类的原则和方法,将北京百花山地区的16个土壤剖面分类为10个土系,并将这16个土壤剖面分别按中国土壤系统分类与地理发生土壤分类系统进行分类参比,结果表明,土系与土种单元在性质上基本一致,以它们为基础进行大比例尺调查制图所得图斑也必然相似;而在土系与土种以上的分类阶层,因为所使用的分类标准不同,两个分类系统划分的分类单元和据此进行的制图图斑则不一样;以土类为基础进行小比例尺制图,使用中国土壤系统分类只能复区制图,而使用地理发生土壤分类系统则可以单区制图。  相似文献   

11.
我国九个农业经济自然区土壤背景值图的编制   总被引:4,自引:1,他引:3  
总结了我国九个省区主要经济自然区土壤污染元素背景值图编制中取得的一些主要经验与成果。  相似文献   

12.
贡嘎山海螺沟土壤环境背景复杂,土壤元素背影值中,Cu,Zn,Pb,Cr,Ni,Mn和F都高于全国土壤的背景水平,而元素Cd,As,Se则相反;各土类间同一元素含量的变化不大;成土母质对土壤元素含量的影响深刻;土壤元素含量的垂直分异规律不明显。  相似文献   

13.
A curve-fit model of the relationship between soil pH (A horizon) and climate forms the basis of a map of predicted pH for the conterminous United States. This map was produced with the aid of a large climatic data base, a computer mapping program and subroutines to map modeled values of soil pH. Patterns of pH follow well-recognized patterns of climate, although the pH of 7 line deviates greatly from Marbut's line dividing pedalfers from pedocals. The overall accuracy of the map and model was checked using a validation data set. Geographic patterns of pH are realistic, although land use, topography, and parent material may cause local variations about the predicted mean for a given region. Several apparently anamolous map patterns were also checked but found to be accurate. Prediction of the detailed pattern of pH will require variables in addition to climate.  相似文献   

14.
不同地质背景下发育的土壤及其对物种多样性的影响   总被引:3,自引:0,他引:3  
以重庆金佛山地区为例,分析土壤基本理化性质与成土母质和植被的关系,并对石灰岩和砂页岩地区的生物多样性及其与土壤基本理化性质的关系进行了探讨。结果表明,成土母质对土壤基本理化性质的影响主要体现在钙镁总量上,但这种影响随着土壤发育的成熟和植被正向演替的进展逐渐减弱;不同母质地区的物种多样性指数均与土壤钙镁含量呈明显的负相关,在土壤发育和生态恢复初期,土壤中较高的钙镁含量对物种多样性有一定的限制作用;石灰岩地区的物种多样性与土壤因子的关系更为复杂,导致群落的不稳定性增强。  相似文献   

15.
基于GIS的土壤全氮空间分布估算——以江西省兴国县为例   总被引:7,自引:0,他引:7  
运用GIS的空间分析技术和DEM,在区域范围内,可以表征基于母岩和地形因子的土壤-景观模型。本次研究根据兴国县151个样点数据,分析TN和地形因子的相关关系,建立回归模型,进行估算。结果表明:表层土壤中TN含量平均值为1.06g/kg,千枚岩发育的土壤中TN的平均含量最高,为1.35g/kg ;砂页岩发育的土壤中TN的平均含量最低,为0.88g/kg 。空间分布上:TN含量在0.5g/kg~1.0g/kg的面积最大,为1580km2,TN含量在2.0g/kg以上的面积最小,为127km2。地形变量中坡向对TN含量影响最大,TN含量和母岩、海拔、坡向存在着正相关关系,坡度和TN含量的相关关系不明显。利用回归分析模型和DEM(30m×30m),估算TN的空间分布,R2为0.637。  相似文献   

16.
哀牢山徐家坝地区土壤中12种元素的自然背景值   总被引:3,自引:0,他引:3  
分析了云南的哀牢山徐家坝地区黄棕壤中12种元素的背景值。讨论了成土母质类型和植被类型对土壤中元素的背景值的影响。  相似文献   

17.
In an attempt to elucidate the spatial variability of soils as a preliminary to detailed mapping, 100 sites within a single parent material stratum were sampled along a grid of parallel traverses. The data collected have been subjected to statistical analyses, notably determination of coefficient of variation (CV) and principal component analysis (PCA). These analyses indicate that the soils of the area of study display marked variability which does not correspond to the variability in parent material, that the spatial variations of soil chemical properties are mainly due to variations in both the clay and organic matter contents of the soils, and that textural characteristics may be used as differentiators to produce groups with precise edaphological meanings in this environment. Such groupings must, however, take cognizance of the considerable local variations due to anthropogenic factors.  相似文献   

18.
残积母质是青海湖地区重要的成土母质之一,目前对高原残积母质土壤的研究相对匮乏,特别是其形成发育的年代尚不明晰,限制了对高原残积母质土壤演变过程的认识及对区域气候环境演变的理解。为探究青藏高原东北部残积母质土壤的发育过程及其发育模式,以青海湖北部宁夏(NX)剖面作为研究对象,通过光释光(Optically stimulated luminescence,OSL)测年获得残积母质土壤发育年代,采用化学蚀变指数(Chemical index of alteration,CIA)、Rb/Sr和粉黏比等探究土壤发育程度,对比青海湖地区河湖相沉积和黄土的Zr/Nb、K2O/Al2O3和TiO2/Al2O3分析其物源。结果表明:NX土壤剖面在早全新世以来发育,其年代结果集中在10.02~8.67 ka,成土母质发育时间与流域内风沙强烈活动时期基本一致,为干暖气候背景下的产物;通过物源对比分析,NX剖面底部母质为母岩就地风化而成,上部为风尘加积发育,发育模式为混合母质风尘加积型;剖面整体处于弱化学风化阶段,土壤发育程度较弱。  相似文献   

19.
《自然地理学》2013,34(1):78-96
Soil erosion has been recognized as one of the major forms of human-induced soil degradation. Due to land use changes in Iran, erosion has increased 800% between 1951 and 2002, calling for urgent action. But erosion research and policy development are hampered by a lack of information on the underlying factors controlling erosion. Soil types vary in their inherent susceptibility to erosion; but, like most countries, Iran lacks a network of field plots where erodibility is measured. A proxy for erodibility based on existing data and supplemented by an easily measured minimum data set is therefore needed. In this study, we use geological mapping and cluster, principal component, and factor analysis to group soils in the Taleghan Drainage Basin in Iran and subsequently determine their erodibility. First, a geological map of the area was prepared by photogeological methods and on-the-ground verification. Then, three soil profiles were investigated within similar landform units of each geological formation, and soil samples were taken. Physical and chemical properties that might impact soil erodibility (soil texture, pH, electrical conductivity, CaCO3, and soil organic matter) were used to create a matrix of soil properties and parent material. Application of cluster analysis and factor analysis to the data allowed identification of three geological (parent material) clusters. To investigate the mutual effect of land use and parent material on soil erodibility, a soil erodibility factor was obtained for three land use types in each cluster: rangeland, cropland (irrigated), and dry-land farming (nonirrigated). Geological cluster 1, consisting of marl, gypsum, and gypsiferous mudstone, was the most erodible; geological cluster 2, consisting of recent alluvium, alluvial fan, and landslip deposits, was of intermediate erodibility; and geological cluster 3, consisting of igneous rocks, dolomite, and conglomerate, was the least erodible. Within each geological cluster, dry-land farming was the most erodible, cropland was medium erodible, and rangeland was least erodible. The study suggests that geological and land use maps provide a useful framework for assessing soil erodibility. This work can guide future soil erosion studies and direct soil conservation policy to areas most susceptible to erosion.  相似文献   

20.
In this contribution, we used discriminant analysis (DA) and support vector machine (SVM) to model subsurface gold mineralization by using a combination of the surface soil geochemical anomalies and earlier bore data for further drilling at the Sari-Gunay gold deposit, NW Iran. Seventy percent of the data were used as the training data and the remaining 30 % were used as the testing data. Sum of the block grades, obtained by kriging, above the cutoff grade (0.5 g/t) was multiplied by the thickness of the blocks and used as productivity index (PI). Then, the PI variable was classified into three classes of background, medium, and high by using fractal method. Four classification functions of SVM and DA methods were calculated by the training soil geochemical data. Also, by using all the geochemical data and classification functions, the general extension of the gold mineralized zones was predicted. The mineral prediction models at the Sari-Gunay hill were used to locate high and moderate potential areas for further infill systematic and reconnaissance drilling, respectively. These models at Agh-Dagh hill and the area between Sari-Gunay and Agh-Dagh hills were used to define the moderate and high potential areas for further reconnaissance drilling. The results showed that the nu-SVM method with 73.8 % accuracy and c-SVM with 72.3 % accuracy worked better than DA methods.  相似文献   

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