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1.
Conception soil maps for urban areas The demand for soil maps increased strongly during the last years. This concerns urban soils, too. Conception soil maps constructed from a lot of basic informations (basic maps and point data) are the alternative to traditional soil mapping, which is expensive in time and money for urban areas. Further informations are to evaluate maps from these conception soil maps. Using graphic information-systems is advantageous for construction and evaluation.  相似文献   

2.
Agricultural soil maps were created to facilitate the management of fields. Such maps, at very large scale (1:5000), cover almost the entire agricultural land in Poland. These maps can be very useful for precision field management. However, they were prepared about 40–50 years ago using old mapping techniques with mainly field (organoleptic) examination of soil. For this reason it is necessary to verify agreement between such maps with the current soil status. In the case of detection of disagreements it is important to identify the causes and propose methods for improving soil maps. Only few studies were made in this aspect. The soil texture (ST) of the upper layer, as presented on the agricultural soil maps from the 1960s and 1970s, was compared with the actual ST of the same four fields in northern and central Poland. For laboratory ST determination, soil samples were collected in a dense sampling network. On average, the agreement of the ST presented on the agricultural soil maps and determined in this study was classified as medium for three fields and good for one field. However, the presence of field areas with poor agreement between the ST determined in this study and that shown on the agricultural maps was detected in all investigated fields. Identified causes for this comprised imprecision of ST determination using the organoleptic method, the generalization of the soil quality maps, and erosion processes during the years between soil mapping and this investigation. The improvement of ST presentation on the large scale soil maps might be achieved by quite denser soil sampling for ST analysis supported by ECa, yield and NDVI maps.  相似文献   

3.
以国家科技基础性工作"我国土系调查与‘中国土系志’编制"的研究工作为基础,系统地整理了浙江省金衢盆地(金华盆地和衢州盆地)的土系调查数据及土壤图、地形图、土地利用现状图和行政区划图等图形数据。在ArcGIS和Microsoft Office Access的支持下,建立了金衢盆地土系数据库,实现了区域内土系信息资料的高效有序管理,从而推动研究区现代农业的发展。  相似文献   

4.
基于土壤-环境关系的更新传统土壤图研究   总被引:4,自引:0,他引:4  
传统土壤图是流域管理、生态水文模型所需土壤空间分布信息的主要数据源。然而,受传统制图技术和基础数据质量所限,传统土壤图的空间详细度和属性精确度并不高。随着地理信息技术的发展,如何利用可获取的高质量空间数据和现代空间分析技术来更新传统土壤图显得十分必要。基于传统土壤图中的土壤多边形与通过模糊聚类所得环境因子组合之间存在着对应关系这一假设,本文提出了一种从传统土壤图中提取土壤-环境关系知识并利用该知识更新传统土壤图的方法。该方法包括四个步骤:对环境数据进行模糊c均值聚类获取环境因子组合;利用传统土壤图建立环境因子组合与土壤类型间的对应关系;提取土壤-环境关系知识;进行土壤推理制图。将该方法应用于加拿大New B runsw ick省的W akefield研究区,以更新该区现有的1∶20 000的传统土壤图。应用结果表明:更新后的数字土壤图显示了更详细的空间分布信息;经野外独立验证点验证,所得土壤图(制图单元为土壤组合-排水等级)精度高出原土壤图约20%。因此,该方法是一种有效的更新传统土壤图的方法,可增加土壤图的空间详细度、提高土壤图的属性精确度。  相似文献   

5.
基于GIS的农田土壤水分状况管理模型及应用   总被引:2,自引:1,他引:1  
基于GIS开发了土壤水分和土壤电导率的简单专题图及精细专题图模块。简单专题图为运行于农田PDA的嵌入式GIS系统提供采样异常点检查验证;精细专题图为运行于上位机的农田信息处理系统提供信息可视化管理。简单专题图调用GIS组件方法获得并据此建立了采样管理模型;精细专题图中,土壤水分采用克里金插值算法预测的均方根百分比误差(RMSPE)为5.489%;土壤电导率插值模型采用泛克里金算法预测的RMSPE为18.451%。基于精细农田信息专题图,根据特定作物不同生长时期需水量的专家推荐值建立了土壤水分管理模型,利用该模型进行的一次灌溉决策显示,土壤含水率方差从灌溉前的1.9168调整到了灌溉后的0.8906。试验表明,采样管理模型能够指导田间采样,农田水分管理模型能够指导农田灌溉。  相似文献   

6.
基于数据挖掘模型的土壤图更新是一项重要的研究。数据挖掘模型构建中训练样点的质量不仅决定其对研究区土壤-环境关系表达的充分程度,而且会对推理制图的结果产生至关重要的影响。本文提出一种基于土壤类型面积分级的典型训练样点选择方法,即依据土壤面积对土壤类型分级,并按照等级之间的比例关系基于典型点选择训练样点。将方法应用于更新美国威斯康星州Raffelson流域的传统土壤图,并与另外两种训练样点选择方法对比,以验证该方法的有效性。结果表明,500次重复实验中,本研究方法与另外两种训练样点选择方法相比,能够更新传统土壤图的比例分别为79.5%、71.8%和63.6%,而且其推理制图结果更符合研究区土壤分布的特征。本研究所提方法是一种有效的训练样点选择方法。  相似文献   

7.
Abstract. Information about the soil fertility status in irrigated ricelands at regional scales (1:50 000–1:250 000) is commonly not contained in classical soil maps. To assess the agronomic suitability of two different reconnaissance soil maps, we conducted a detailed soil survey in the Nueva Ecija province, Philippines. Soil samples were collected from 384 farmers' fields, and soil properties were measured for topsoil and subsoil samples. For most soil properties, a soil map made in 1940 (1:125 000) had within-map unit variances that were smaller than the total variance, whereas a new soil map of 1992 (1:50 000) did not significantly reduce the within-class variance. In both soil maps, classification into mapping units accounted for 0–40% of the variance of 14 agronomically important soil properties and large within-map unit variabilities were found. Underlying strategies of classical soil survey supported the partition of variance for relatively stable soil properties, such as soil texture, CEC, and organic matter. If reconnaissance soil maps are used in quantitative land evaluation studies, existing maps require upgrading by adding quantitative information about relevant soil properties and their within-map unit variability The sampling demand for upgrading a reconnaissance soil map was large, but pedotransfer functions can be used as cost-saving tools. Measures of soil nutrient status were highly variable within all mapping units and differences among farmers were much greater than the differences between soil types. Therefore, nutrient management in the study region should be based on individual field or farm recommendations rather than on soil-map based recommendations.  相似文献   

8.
A methodology for comparing soil map of different dates in order to reveal changes in the soil cover is discussed. The analysis of a set of the maps of soil salinization on one of the farms in the Golodnaya Steppe region of Uzbekistan is used as an example. It is shown that traditional methods of comparing two maps developed in different years (normally, with an interval of five years and more) are low informative for the assessment of soil salinization dynamics. The suggested methodology assumes simultaneous analysis of several maps in order to reveal the trends in soil salinization. However, even in this case, the obtained results do not adequately characterize the dynamics of soil salinization on irrigated fields. It is argued that the direction of soil salinization–desalinization processes is an improper characteristic in this case. In order to understand the dynamics of soil salinization, the maps showing the dynamism of soil salinity and the maximum changes in the degree of salinity can be applied. A series of the compared maps make it possible to describe the changes in the soil cover related to salinization–desalinization processes. The high dynamism of these processes against the background of a virtually stable pool of soluble salts in the 1-m-deep soil layer is shown for the considered farm.  相似文献   

9.
THE RELATION BETWEEN COST AND UTILITY IN SOIL SURVEY   总被引:1,自引:0,他引:1  
This paper discusses how to compare the utility of soil maps. For three contrasting areas, in Southern England, it compares the utilities of a number of single-property and general purpose (series) soil maps, produced by free and grid survey, at map scales from 1 :20,000–1:70,000. The‘purity’of series mapping units increases with survey effort. Where the soil boundaries had fairly clear external expression free survey was superior to grid survey. On average the purity of maps by grid survey was higher than for maps by free survey at comparable survey effort. The uniformity of soil properties within mapping units was measured by relative variance (RV)= within-unit variance/total variance, (1–RV) indicates the increased precision achieved by the soil map. It increased with survey effort. For series maps by free or grid survey (1–RV) depended on how closely soil properties were associated with profile classes, and on the extent to which soil boundaries could be mapped on their external expression. Free survey was preferred at scales between 1: 100,000 and 1:30,000, when the soil boundaries could be mapped on their external expression, (1–RV) for the profile classes on which the mapping units are defined puts a ceiling to the utility of series maps (grid or free) which is already nearly achieved at map scales near 1:25,000. Except for properties very poorly associated with profile classes, single property maps do not have great advantage over series maps at medium map scales, but they attain higher values of (1–RV) at scales greater than 1: 25,000.  相似文献   

10.
Eurasian Soil Science - Large-scale soil maps produced by research institutes for land management (GIPROZEM) are the main source of soil information on arable land in Russia. These maps date back...  相似文献   

11.
Human activities, such as military off‐road vehicular traffic, disturb ground and vegetation cover of landscapes and increase potential rainfall related runoff and soil erosion. On military lands, soil erosion is of major concern in order to sustain training lands and thus there is a need for land condition maps for planning training activities and land management. In this study, we presented a conditional co‐simulation algorithm to generate annual time series maps of soil erosion status from 1989 to 2001 for an army installation. The spatial variability and temporal dynamics of land condition were analyzed. This algorithm modeled soil erosion as realizations of a random function by combining a set of permanent plot data and Landsat Thematic Mapper (TM) images. In addition to estimation maps of soil erosion status, we obtained the maps of uncertainties including the variance of each pixel estimate and the probability of poor land condition. The results and maps are useful tools for land managers and decision‐makers to guide military training programs and to generate management plans for sustaining training lands. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

12.
This study compares different soil mapping approaches in three different petrographic areas in order to test their suitability for regional mapping in northern Thailand. Sampling was based on transects or grid-based randomization. Maps were created based on expert knowledge (eye fitting) or using Classification Tree (CART algorithm) or the Maximum Likelihood approach. In addition, local knowledge-based-soil maps were created. Validation was performed using soil reference maps and independent sampling points. The mapping approaches based on transects and grid-based randomization showed a very high correspondence with the respective reference soil map and a very high degree of matching with independent sampling points. Both methods are best suited for sub-watershed scale. Mapping larger areas is difficult due to the inaccessibility of the mountainous regions. The soil maps based on Maximum Likelihood showed a high correlation with the respective reference soil maps and the individual sampling points. Maximum Likelihood maps and Classification Tree maps showed similar levels of accuracy. The Maximum Likelihood approach is applicable to upscaling procedures; therefore, a calibration area is required which represents the target area. Local knowledge-based-soil mapping is very cheap and fast, but is restricted to village areas where classification often varies even within a village. Despite this, local knowledge is very useful for soil reconnaissance surveys, as well as to acquire an overview of the major distribution of soils and their properties. Upscaling of local knowledge due to its inherent inconsistency is not realistic.  相似文献   

13.
安徽省岳西县土壤侵蚀时空演变特征及趋势预测   总被引:1,自引:0,他引:1  
利用ArcView 3.3软件,对岳西县1958年、1983年、1992年的土壤侵蚀动态监测图进行屏幕数字化,得到三期土壤侵蚀强度矢量图;利用2004年TM影像,通过目视解译的方法,得到2004年土壤侵蚀强度矢量图。利用Arc-GIS软件,对不同时段土壤侵蚀图进行叠加分析,研究了不同时段不同土壤侵蚀强度面积数量的相互转化及土壤侵蚀程度的变化;运用马尔柯夫模型,预测岳西县土壤侵蚀动态演变趋势。主要结论如下:(1)岳西县土壤侵蚀状况1958-2004年经历了急剧恶化到逐渐恢复的过程。1958-1983年土壤侵蚀不断加剧;1983-1992年土壤侵蚀逐渐恢复;1992-2004年土壤侵蚀进入全面恢复期。(2)相邻时段的土壤侵蚀图叠加结果分析表明,不同时期土壤侵蚀各等级是相互转化的。(3)1958-2004年岳西县土壤侵蚀程度无变化的面积经历了先下降后上升的过程,土壤侵蚀程度等级增加的面积先显著扩大再逐步下降,而土壤侵蚀程度等级下降的面积先减少后增加。(4)马尔柯夫模型预测结果表明,到2016年微度侵蚀土壤面积增加到64 221hm2,中度侵蚀类型面积明显下降;强烈侵蚀与极强烈侵蚀土壤在局部地区有所增加,但这种变化不明显。堆积类型面积呈显著下降趋势,水域面积有所减少。从总体趋势看土壤侵蚀状况向良性循环方向发展。  相似文献   

14.
An approach for the updating of medium-scale soil maps is discussed. It is based on the use of modern remote sensing and geoinformation technologies. The boundaries of soil polygons shown on the old soil maps and their soil contents are corrected using geoinformation analysis of modern topographic data and automated interpretation of vegetation conditions as reflected on satellite imagery. The developed methods are illustrated by the particular examples.  相似文献   

15.
A map of soil cover patterns in the Tugnuisk Depression of the Transbaikal region has been compiled on a scale of 1:500 000. This map contains information on the distribution of soil complexes and soil combinations and on the genetic and geometric characteristics of soil areas. It is derived from the original large-scale soil maps. The theory of soil cover patterns was used as the basis for cartographic generalization. This made it possible to preserve information on soil types and subtypes identified on the original maps and to show the real distribution pattern for all the components of the soil cover.  相似文献   

16.
Land reclamation by rock removal has wide potential in areas with shallow or rocky soils. In northwest Syria, this practice is hindered in its implementation by a lack of physical soil suitability data, principally soil rockiness and soil depth to hard rock. These soil properties were surveyed in a limited study area, resulting in a hard‐boundary thematic soil map (64–94% accuracy per property). Bayesian inference is proposed as a low‐cost upscaling method that yields a set of pixel‐based probability maps, providing improved input for spatial decision support models. Whereas the achieved spatial upscaling (from 2510 to 19 100 ha) outweighed the decrease in overall accuracy (down to 26–57%), probability maps require dedicated validation and manipulation procedures. This research contributes to methods for the creation, validation and interpretation of probabilistic soil property maps for quantitative land evaluation. First, we evaluated three postprocessing and validation methods for probabilistic soil property maps, identifying the use of ‘prediction rates’ as the best approach in a spatial planning context. Next, we demonstrated how the maps can support decision‐making for land management activities by simulating the expected losses and gains from interventions, in a decision‐theoretic approach. Based on the simulations, the investments in large‐scale derocking projects in northwest Syria will pay off in terms of increased agricultural productivity in less than 10 years.  相似文献   

17.
Gerald W. Olson 《Geoderma》1973,9(4):257-267
The employment of soil information for improving efficiency of land use can be increased in Latin America. Soil maps are being published with more detail at larger scales, and soil characterization is becoming more quantitative. Uses of soil information are expanding to include engineering and comprehensive planning aspects as well as agricultural recommendations for production increases. Opportunities exist for improving the usefulness of soil maps even further by interdisciplinary efforts of soil scientists with geographers, conservationists, planners, economists, engineers, anthropologists, and others in Latin America.  相似文献   

18.
Recent development of digital soil mapping (DSM) allowed improving significantly the quality of soil maps. We tried to make a set of empirical models for the territory of Karelia, a republic at the North-East of the European territory of Russian Federation. This territory was selected for the pilot study for DSM for two reasons. First, the soils of the region are mainly monogenetic; thus, the effect of paleogeographic environment on recent soils is reduced. Second, the territory was poorly mapped because of low agricultural development: only 1.8% of the total area of the republic is used for agriculture and has large-scale soil maps. The rest of the territory has only small-scale soil maps, compiled basing on the general geographic concepts rather than on field surveys. Thus, the only solution for soil inventory was the predictive digital mapping. The absence of large-scaled soil maps did not allow data mining from previous soil surveys, and only empirical models could be applied. For regionalization purposes, we accepted the division into Northern and Southern Karelia, proposed in the general scheme of soil regionalization of Russia; boundaries between the regions were somewhat modified. Within each region, we specified from 15 (Northern Karelia) to 32 (Southern Karelia) individual soilscapes and proposed soil-topographic and soil-lithological relationships for every soilscape. Further field verification is needed to adjust the models.  相似文献   

19.
长江以南东部丘陵山区土壤可蚀性K值研究   总被引:35,自引:5,他引:35  
以土壤亚类为基础,从土种入手,依据第二次土壤普查资料建立了我国东产丘陵区各土种的理化性质数据库。应用土壤可蚀性方法,计算出各土种的土壤可蚀性K值,用面积进行加权平均,经分类分级后,连续到相应的土壤图上,得到我国东部丘陵区土壤可蚀性K值图及其分布规律。  相似文献   

20.
Methodological problems of large-scale soil mapping with the use of digital mapping technologies are discussed. Two variants of obtaining the maps of soil combinations for a test polygon (30 km2) in the area of soddy-podzolic soils with 996 studied soil pits are described. In the first variant, the initial state of soils at studied points was characterized by the taxonomic name of the soil (at the level of soil subtypes); the probability of occurrence of different subtypes within operation cells of the digital map was estimated, and the most probable soil subtypes were assigned to them. This approach was tested for the first time. In the second variant, the initial state of soils at studied points was described with the help of the grades of ecologically meaningful features of soil morphology; the degree of soil gleying and the degree of soil erosion or aggradation were indicated. The integral digital map represented the areas of different agroecological groups of soil combinations. The maps obtained with the help of these two approaches show a satisfactory agreement with the maps of soil cover patterns compiled by traditional methods earlier.  相似文献   

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