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1.
Fahlerden dominate large areas of the young and old moraine landscapes of N and E Germany. Fahlerden (part of Fahlerden corresponds to Albeluvisols) and their transitional subtypes are supposed to have a higher intensity of clay illuviation than Parabraunerden (Luvisols). Besides this macroscopic feature reflecting periglacial influence, micromorphological features such as lenticular platy microstructure, vesicles, and fragments of clay coatings in Bt streaks document the initiation of Fahlerde genesis, which began in the Late Glacial. A model of Fahlerde genesis chronologically connects sedimentological and periglacial processes, vegetation development, and soil‐forming processes like decalcification, clay illuviation, and humification. The classification criterion of larger differences in clay contents between E and Bt horizons to distinguish Fahlerden from Parabraunerden needs to be reconsidered, because most Fahlerden have developed in stratified parent material in periglacially influenced landscapes. The interpretation of a soil data base listing data of both soil types distributed in Brandenburg demonstrates that the difference in clay contents between E and Bt horizons may even be smaller in Fahlerden than in Parabraunerden.  相似文献   

2.
自组织竞争人工神经网络在土壤分类中的应用   总被引:31,自引:0,他引:31  
利用自组织特征映射网络 (SOM网络 )的聚类功能 ,应用 MATL AB 5 .3软件编程 ,对三江平原地区的 2 1个土壤采样进行了分类 ,并与有关文献的模糊聚类分析结果进行了比较 ,指出 SOM网络可以很好地反映、提取土壤样本间复杂的信息 ,分类效果较好 ,可以在土壤分类中应用  相似文献   

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4.
Characteristics of Clay Minerals in Podzols and Podzolic Soils   总被引:1,自引:0,他引:1  
The clay minerals in Podzols and podzolic soils developed under coniferous forests in the Subarctic and Cool-temperate zones are characterized by the predominance of smectite and/or mica-smectite interstratified minerals in the eluvial horizons and chlorite-vermiculite intergrade in the illuvial horizons. A large amount of vermiculite is present in the eluvial horizons of some podzolic soils in the Cool-temperate zone. The illuvial horizons of these soils also contain free iron oxides such as goethite. Imogolite and allophane are present in the illuvial horizons of several soils derived from volcanic ashes. It is suggested that the critical bioclimate for the release of interlayered aluminum from the 2:1-type minerals lies between the Cool- and Warm-temperate zone. In the eluvial horizons of Podzols and podzolic soils, mica minerals and chlorite, as primary minerals, have been transformed to smectite through the pedogenic process. Based on previous studies on the structure and degradation of the dioctahedral mica minerals, it is considered that smectite is transformed from 1M-type mica minerals directly, and from 2M-type mica minerals via mica-smectite interstratifled minerals. The formation of a smectite lattice in the eluvial horizon should be a clay-mineralogical indicator of podzolization.  相似文献   

5.
运用分类树进行土壤类型自动制图的研究   总被引:1,自引:0,他引:1  
提供了一种基于机器学习的方法来自动建立针对土壤资源制图的规则库。以浙江省龙游县研究区为例,将已有的土壤图与地质图、土地利用现状图、DEM及其派生属性、双时相的TM卫星数据相结合,使用分类树算法从训练数据中生成该地区土壤制图的规则知识,并进行了研究区土壤类型的知识分类。这种建立土壤自动制图知识库的方法要比传统的知识获取方法更为简便易行。精度评价结果表明,所建立的知识库对于研究区的大部分土壤类型的预测是可行的。  相似文献   

6.
Biological activities greatly influence the formation of many soils, especially forest soils under cool humid climates. The objective of this study was to investigate the effects of vegetation and soil biota on the formation of selected soils. Field morphology, micromorphology, and carbon and organic matter analysis were determined on six Podzols (Spodosols) and two Cambisols (Inceptisols) from the eastern United States and north-east Scotland. Humification of plant material by soil fauna and fungi occurs in all organic horizons. Thick organic coatings are observed on soil peds and rock fragments from the E1 to the Bs horizon in a Haplic Podzol from Clingmans Dome Mt., TN. Thin sections reveal large accumulations of root material in different stages of decomposition in the spodic horizons of a Haplic Podzol from Whiteface Mt., NY. Organic carbon ranges from 5.4 to 8.5% in the spodic B horizons of the Whiteface Mt. Podzol. Earthworms and enchytraeids have a great effect on the structure of the surface and subsurface horizons in the Dystric Cambisols from Huntly and Clashindarroch Forests, Scotland and a Cambic Podzol from the Corrie Burn Basin, Scotland. Podzols from Speymouth Forest, Scotland (Gleyic Podzol), Clingmans Dome Mt., and Whiteface Mt. have thick organic horizons. The Podzols from the Flatwoods in Georgia, the Pine Barrens in New Jersey, the Corrie Burn Basin, and the Cambisol from Huntly Forest have only A horizons at the surface. The Clashindarroch Forest soil has a very thin organic horizon. Warm and humid climates and sandy parent material are responsible for thick E horizons and lack of thick organic horizons in the Flatwoods (Carbic Podzol) and Pine Barrens (Ferric Podzol) soils. Earthworms and enchytraeids thrive in the Corrie Burn Basin and Huntly Forest soils due to the vegetation and the highly weathered basic parent material. The site at Clashindarroch once carried oak, and then birch forest, both of which produce a mild litter and also encourage earthworm and enchytraeids. This fauna is responsible for much mixing of the topsoil. The present conifer vegetation will eventually produce a deep litter and cause podzolization.  相似文献   

7.
柳新国家复垦示范区充填复垦土壤性质及其分类建议   总被引:3,自引:0,他引:3  
研究了徐州柳新采煤塌陷地充填复垦土壤的pH值和全氮全磷以及有效钾的的性质,并对复垦土壤的分类提出建议。结果表明,该区充填复垦土壤受地下水碱性影响严重;复垦土壤养分中氮和磷含量受影响较大;土壤养分变化受种植作物影响最大,其次是复垦时间长短;充填物性质在短期内对表层土壤性质无明显影响。建议在系统分类中增加复垦表层,扩充人为新成土亚纲的内涵,增设复垦人为新成土土类。  相似文献   

8.
模糊物元模型在土壤侵蚀等级划分中的应用   总被引:1,自引:0,他引:1  
付静  刘国东  张贞  陈彩明  徐尧 《水土保持通报》2008,28(3):138-140,192
土壤侵蚀等级的确定是水土保持工作中的重要问题.参照土壤侵蚀强度分级拟定标准进行等级划分时,由于其标准是界限明显的量化标准,指标的选择,权重及侵蚀程度、范围等都具有模糊性.在物元分析方法中引入模糊数学中的隶属度概念,建立模糊物元模型来确定土壤侵蚀强度等级更具合理性.通过实例分析,并与模糊综合评判方法和实际调查结果进行对比,表明此模型是合理、可行的.  相似文献   

9.
There is increasing interest in developing automatic procedures to segment landscapes into soil spatial entities that replace conventional, expensive manual procedures for delineating and classifying soils. Geographic object-based image analysis (GEOBIA) partitions remote sensing imagery or digital elevation models into homogeneous image objects based on image segmentation. We used an object-based methodology for the detailed delineation and classification of soil types using digital maps of topography and vegetation as soil covariates, based on the Random Forests (RF) classifier. We compared the object-based method's results with those of a pixel-based classification using the same classifier. We used 18 digital elevation model derivatives and 5 remote sensing indices that were related to vegetation cover and soil. Using 171 soil profiles with their associated environmental variable values, the RF method was used to identify the most important soil type predictors for use in the segmentation process. A stack of raster-geodatasets corresponding to the selected predictors was segmented using a multi-resolution segmentation algorithm, which resulted in homogeneous objects related to soil types. These objects were further classified as soil types using the same method, RF. We also conducted a pixel-based classification using the same classifier and soil profiles, and the resulting maps were assessed in terms of their accuracy using 30% of the soil profiles for validation. We found that GEOBIA was an effective method for soil type mapping, and was superior to the pixel-based approach. The optimized object-based soil map had an overall accuracy of 58%, which was 10% higher than that of the optimized pixel-based map.  相似文献   

10.
黄淮海平原土壤盐渍化状况的数值分类   总被引:13,自引:0,他引:13  
本文通过GPS定位的网格取样和Q型聚类等方法,研究了整个黄淮海平原土壤盐分的剖面特征与水平分布.结果表明:根据黄淮海平原土壤盐分的剖面构型,可将整个黄淮海平原的剖面特征分为4大类,即表聚型、 底聚型、中聚型和平衡型.从其占聚类剖面的数量而言,它们分别占总聚类剖面数的约30%、5%、13%和52%.黄淮海平原各种土壤盐分剖面类型都具有明显的空间集聚性,其中表聚性剖面主要分布在徐淮及滨海地区,底聚剖面主要分布在原来盐渍化严重的豫东黄泛平原,中聚剖面主要分布在黑龙港下游地区.其它为平衡型剖面.这类剖面根据其特点,可分为山前平原土壤盐分淋溶区、鲁西南土壤盐分通体积聚区和浅层咸水影响下的土壤盐分平衡区.整个黄淮海平原土壤剖面中脱盐与积盐比例约为2∶1.所以土壤盐分以脱盐为主.  相似文献   

11.
Land use change (LUC) alters soil structure and, consequently, the functions and services provided by these soils. Conversion from extensive pasture to sugarcane is one of the largest land transitions in Brazil as a result of the growth of the domestic and global demands of bioenergy. However, the impacts of sugarcane expansion on the soil structure under extensive pasture remains unclear, especially when considering changes at the microscale. We investigated whether LUC for sugarcane cultivation impacted soil microstructure quality. Undisturbed soil samples were taken from two soil layers (0–10 and 10–20 cm) under three contrasting land uses (native vegetation—NV, pasture—PA and sugarcane—SC) in three different locations in the central-southern Brazil. Oriented thin sections (30 μm) were used for micromorphological analysis. The total area of pores decreased following the LUC in the following order: NV > PA > SC in both soil layers. The area of large complex packing pores (>0.01 mm²) also decreased with the LUC sequence: NV>PA>SC. Qualitative and semi-quantitative micromorphological analysis confirmed porosity reduction was driven by the decrease in complex packing pores and that biological features decreased in the same LUC sequence as the quantitative parameters. Therefore, LUC for sugarcane expansion reduced microscale soil porosity, irrespectively of soil type and site-specific conditions, indicating that the adoption of more sustainable management practices is imperative to preserve soil structure and sustain soil functions in Brazilian sugarcane fields.  相似文献   

12.
为进一步完善我国水土保持农业技术措施的分类体系,并服务于研究与生产,在论述水土保持农业技术措施的概念、分类现状基础上,依据措施实施的方式、作用和目标,并结合农艺环节,将水土保持农业技术划分为以改变微地形为主的蓄水保墒技术、以提高土壤抗蚀力为主的保护性耕作技术和以增加植物覆盖为主的栽培技术3大类,等高耕作、沟垄种植、坑田、半旱式耕作、深耕翻、保墒、覆盖、深松、少耕、培肥土壤、合理配置作物、播种保苗、栽培13个亚类和等高耕作等44个型,以供参考.  相似文献   

13.
安徽休屯盆地紫色土的特性和系统分类   总被引:2,自引:1,他引:2  
选取了休屯盆地不同时期紫红色沉积岩上发育的 6个紫色土剖面 ,系统地研究了其属性特征 ,并按照中国土壤系统分类的原则 ,鉴定其诊断层和诊断特性 ,检索了土壤系统分类的名称。同时也指出了现行《中国土壤系统分类》在紫色土系统分类应用中存在的问题 ,分析了其原因并提出修订建议  相似文献   

14.
矿山土壤特性及其分类研究进展   总被引:3,自引:1,他引:2  
路晓  王金满  李博  白中科 《土壤》2017,49(4):670-678
矿山土分类是认识矿山土壤的基础,对矿山土壤系统分类研究是进行矿山土壤改良和植被重建的重要基础。本文从物理、化学、生物和污染4个方面阐述了矿山土壤特性的变化及其对矿山土壤系统分类的影响,并对分类名称、依据、指标体系和分类方法的相关研究进展进行了综述。目前,矿山土壤系统分类大多以其特有属性作为分类指标,运用光谱技术、模糊均值法和神经网络模型等方法完成分类。但这些方法都有其自身的优缺点,建议今后因地制宜地选取定量化分类指标,探索将主成分分析等数学模型与光谱等技术相结合的方法进行矿山土壤系统分类,以期为今后矿山土地复垦与利用提供科学依据。  相似文献   

15.
定边县板凳滩移民区土壤发生特性与系统分类研究   总被引:1,自引:0,他引:1  
通过对陕西省定边县板凳滩移民区2 500hm2未利用地的调查及不同深度剖面土样的分析,研究了不同地形和不同植被下土壤的发生特性及系统分类。项目区内土壤没有完整的发生层次;土壤颜色、结构和养分在剖面层次上无明显差异;土壤有机质含量较低,最高1.7871g/kg,最小0.201 7g/kg;土壤碳酸钙无明显的淋溶淀积,剖面中无淀积层;颗粒组成以2~0.02mm粒级的砂粒为主;土壤CEC集中分布在2.5~5cmol/kg,保肥性能差。通过诊断层和诊断特征分析,研究区土壤共分属1个土纲,1个亚纲,2个土类和4个亚类,其中剖面Ⅱ1属于弱盐潮湿砂质新成土,剖面Ⅱ5属于钠质潮湿砂质新成土,剖面Ⅲ4属于石灰潮湿砂质新成土,剖面Ⅵ4属于石灰干润砂质新成土。研究结果可为移民区的土壤资源综合评价、土壤适宜性评价及农、林、牧业合理布局提供依据。  相似文献   

16.
关于城市化土壤侵蚀等级划分综合评判模型的探讨   总被引:9,自引:4,他引:5  
城市化土壤侵蚀问题是城市水土保持规划中的主要问题。在文献[1]的基础上,试图将模糊评判处理方法引入到城市化土壤侵蚀强等级划分的确定。通过各评价因素的确定,以及评判结果的量化,提出了一个简单而又具有可操作性的综合评判模型,从而可作为建立城市水土保持地理信息系统的基础。  相似文献   

17.
中国北方红色土壤分类问题的探讨   总被引:2,自引:0,他引:2  
现今出露于中国北方地表的红色土壤是在红色古土壤和红色古风化壳上发育的,而且大多经历了不连续的成土过程。中国北方红色土壤分布广泛、成因复杂,在分类中还存在着许多问题。从20世纪70年代末至今,我国土壤分类经历了由土壤发生学分类向土壤系统分类的重大转变,对北方红色土壤的分类也进行了多次修订。虽然每次修订都有所改进,但直到目前关于北方红色土壤的分类位置问题仍没有得到彻底解决。因此,今后需要对中国北方红色土壤的形成过程及土壤的性态特征和理化性状进行深入研究,建立适合北方红色土壤系统分类的诊断层和诊断特性,以明确中国北方红色土壤在系统分类中的位置,进一步完善中国土壤系统分类。  相似文献   

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19.
浙江省土壤侵蚀等级划分模糊综合评判模型的初步探讨   总被引:2,自引:1,他引:2  
土壤侵蚀等级的确定是城市水土保持规划中的重要问题。将模糊评判处理方法引入浙江省土壤侵蚀强度等级的确定。通过对各评价指标的分析,以及评判结果的量化,提出了一个具有可操作性的综合评判模型,可用于编制水土保持规划中确定土壤侵蚀等级。  相似文献   

20.
辽宁土壤侵蚀状况分区与防治重点   总被引:4,自引:0,他引:4  
通过对史料研究,阐述了辽宁土壤侵蚀发展的3个阶段,即初始阶段,加速阶段和初步控制阶段,并运用以往的研究资料和最新的遥感普查资料对全省的土壤侵蚀进行了分区,在此基础上提出了各侵蚀区的防治重点,这些都将为土壤侵蚀的防治工作提供重要的科学依据。  相似文献   

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