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1.
土壤溶质迁移的柱滞留方程   总被引:1,自引:0,他引:1  
The relationship between magnetic properties and particle size of soils derived from metamorphic rock,basalt,granite,Quaternary red clay,limestone and mudstone from Zhejiang Province,East China was studied,Based on the variations of the mass magnetic susceptibility (χ),anhysteretic remanent magnetization (ARM),and saturation isothermal remanent magnetization (SIRM) with soil particle size,the relationship could be classfied into three groups.For the soils derived from metamorphic rock and basalt,magnetic values were the highest in the gravel and coarse sand fractions and decreased with decreasing soil particle size.The soils derived from sedimentary rock had a bimodal distribution of magnetic values.with peaks in 1-0.5 and 0.005-0.0005mm fractions.The soil developed on granite was characterized by a peak of magnetic value in 0.001-0.0005mm fractions.The soil developed on granite was characterized by a peak of magnetic value in 0.001-0.0005 mm fractions.Frequency-dependent susceptibility(χfd)and ratios of magnetic parameters (ARM/χ,SIRM/χand SIRM/ARM) of soil particle fractions showed that variations in ferrimagnetic grain size paralleled those in particle size,χfd peaked in caly fraction and decreased with increasing particle size,irrespective of soil parent materials.The acquisition curves of IRM and demagnetization paramenter of different soil particles indicated that there were different magnetic minerals assemblages in different particle fractions.  相似文献   

2.
Vector analysis technique and ecological sequential comparison methods were adopted to study tree growth response to the micronutrients,B,Mo,Cu,Zn,Fe,and Mn,in soils derived from various parent materials in the forest area of Tailhu Lake region in southeast China,The results showed that the dry weight of individual current-year needle of Chinese fir(Cunninghamia lanceolata) grown on the soil derived from granite parent rock was increased by 8% and 13% in comparison with that grown on the soils derived from sandstone and ash-tuff parent rock,respectively.And such dry weight of loblolly pine (Pinus taeda) grown on the soil derived from sandstone parent rock was increased by 21% in comparison with that on the soil derived from ash-tuff parent rock.One of the reasons for those results was that micronutrients content in the soil derived from ash-tuff parent rock were not sufficient to meet the requirement of the growth of Chinese fir and loblolly pine ,i.e.,micronutrients in soil were deficient and/or induced defiient.The amounts of Cu,Zn,Fe,and Mn uptake by Chinses fir and loblolly pine were in agreement with the contents of available micronutrients in soil respectively,except for B and Mo.Meanwhile,there might exist and “antagonism“ between the uptake of B versus Mo by trees,although more studies are needed to confirm it .Regression analysis indicated that amount of a soil available micronutrient was correlated to the type of parent material and its total amount in the forest floor, except for B.The F test identified that the correlation of each equation reached the significant level to different extents,respectively,The t test confirmed that amount of available forms was mainly depended on the type of parent material for Mo,Cu,Zn and Mn but on the forest floor for ,Fe,There was a feedback effect of forest stand on the amount of soil available micronutrients.The ability of accumulating available micronutrients in soil was better by the sawtooth oak(Quercus acutissima) stand than by the Chinese fir stand (except for B).The ability of accumulating available Zn,Fe,Mn and Mo in soil was better by the Chinese fir stand than by the loblolly pine stand ,while as for available B and Cu,by the latter was better than by the former,When discussing the efect of forest stand on the amount of soil available micronutrients,not only the amount of micronutrient in the forest floor and the parent materials but also the amount of micronutrient taken up by current-year needles have to be considered.  相似文献   

3.
The leaching characteristics and the element concentration in soil solution of red soils derived from sandstone,granite,Quaternary red clay and basalt have been studied in the Red Earth Ecological Experimental Station,Academia Sinica,using 12 lysimeters.Results obtained show that the element leaching process of red soils occurs mainly from January to the beginning of July annually.The elements with higher concentration in leaching solution of red soils are Si,Ca,Na,K,Mg,and N.The desilication and the leaching process of base cations occur simultaneously in the red soils.Using the first order differential equation and measured parameters of Si leaching,the leaching models of Si for red soils derived from different parent materials are constructed.The leaching process of Si is simulated with the models.Both the absolute and relative ages of red soils derived from different parent materials are discussed based on the simulation result.On the basis of element leaching,composition of soil solution and thermodynamics,the current soil-forming process is discussed.According to the phase diagram,the kaolinization is prevailing in the current formation of different red soils.  相似文献   

4.
Ninety-three soil samples and 19 sedimentary rock samples collected from 21 provinces of China were analyzed for their contents of fixed ammonium and total N by Kjeldahl-HF method. Results showed that amount of difficultly extractable fixed ammonium (the fixed ammonium that is not determinable by Kjeldahl procedures commonly used for soils) in soils ranged from 0 to 202 mg kg-1. It was generally more than 50 mg kg-1 in soils in Changji and Turpan districts, Xinjiang, accounting for 3.2%~36.8% with an average of 13.9% of the total N. For some Orthents derived from purple shale and purple sandstone in Sichuan and Hunan provinces and Chao soils derived from secondary loess in Henan Province and Ningxia Autonomous Region it was generally around 30 mg kg-1, accounting for 4%~7% of the total soil N, and for most of the rest of soils studied, with the exception of some subsoils, no or trace difficultly extractable fixed ammonium could be detected. It was suggested that the difficultly extractable fixed ammonium was originated from parent rock, and for slightly weathered soils derived from parent materials rich in this form of N the Kjeldahl method might give underestimation of total soil N.  相似文献   

5.
土壤母质与茶叶质量的关系初探   总被引:2,自引:0,他引:2  
Six tea plantations with different soil-forming parent naterials,the same tea variety and tea age and similar landforms and management were selected to conduct a systematic study on the realtionship between soil properties and tea quality.The results showed that the quality of tea grown on the soil derived from dolomites,Quaternary red clays,were inferior.Further study showed that sandy soils were beneficial to improving amino acid content of tea ,and clayey soils made it decrease;high content of bases might decrease the contents of tea polypenols,caffeine,water extracts,but promote the content of amino acds;available phosphorous was significantly positively correlated with water extracts ,but significantly negatively correlated with caffeine;slowly avaiable potassium was positively correlated with amino acid content .Soil parent materials should be regarded as an important factor in eveluating the adatability of tea to soils.  相似文献   

6.
This paper is a review of some advances in the studies on 1.4-nm intergrade mineral of soils in subtropical China. 1)1.4-nm intergrade mineral occurs ubiquitously in soils of subtropical China. The 1.4-nm mineral in red soil and yellow soil is mainly 1.4-nm intergrade mineral, and in acidic yellow-brown soil (pH < 5.5) is vermiculite alone or 1.4-nm intergrade mineral together with vermiculite. The distribution and the content of 1.4-nm intergrade mineral in the mountain soils are more widespread and higher than those of the corresponding soils in horizontal zone. 2) The interlayer material of 1.4-nm intergrade mineral in these soils appears to be hydroxy-A1 polymers instead of hydroxy-Fe, proto-imogolite or kaolin-like material. There is a significant positive correlation between A1 amount extracted from the soil with sodium citrate after DCB extraction and pH value of the citrate solution after the extraction. The citrate can also extract a certain amount of silicon from the soil, but the silicon may not come from interlayer of 1.4-nm intergrade mineral. 3) It was seldom studied that either vermiculite or smectite did the natural 1.4-nm intergrade mineral come from in soil, or it was commonly thought to come from vermiculite. A recent report has revealed that it can come from smectite. There are some different behaviors between the 1.4-nm intergrade mineral derived from vermiculite and that from smectite. For example, they exert different influences on the formation of gibbsite. The 1.4-nm intergrade mineral derived from smectite may promote the formation of gibbsite in the yellow soil. 4) The type of 1.4-nm minerals in soils. i.e., vermiculite or 1.4-nm intergrade mineral, may be significant to soil properties, such as soil acidity, exchangeable Al, electric charge amount and specific surface area. Therefore, the management for the soil in which 1.4-nm mineral is mainly 1.4-nm intergrade mineral or vermiculite should be dealt with differently.  相似文献   

7.
华南兴国县影响土壤侵蚀时空动力学的环境因素   总被引:7,自引:0,他引:7  
By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination with the remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South China were analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The results showed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land under severe erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were more susceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between 7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. These areas deserve special attention in monitoring and controlling.  相似文献   

8.
The clay minerals of more than 200 soil samples collected from various sites of Fujian Province were studied by the X-ray diffraction method and transmission electron microscopy to study their distribution and evolution.Montmorillonite was found in coastal solonchak,paddy soils derived from marine deposit,lacustrine deposit and river deposit,and some lateritic red soil,red soil and yellow soil with a low weathering degree.Chlorite existed mainly in coastal solonchak and paddy soil developed from marine deposit.1.4nm intergradient mineral appeared frequently in yellow soil,red soil and lateritic red soil.The content of 1.4nm intergradient mineral increased with the decrease of weathering degree from lateritic red soil to red soil to yellow soil.Hydrous micas were more in coastal solonchak,paddy soils derived from marine deposit,lacustrine deposit and river deposit.and puple soil from purple shale than in other soils.Kaolinte was the most important clay mineral in the soils iun this province.The higher the soil weathering degree,the more the kaolinite existed.From yellow soil to red soil to lateritic red soil,kaolinite increased gradually,Kaolinite was the predominant clay mineral accompanied by few other minerals in typical lateritic red soil. Tubular halloysite was a widespread clay mineral in soils of Fujian Province with varying quantities.The soil derived from the paent rocks rich in feldspar contained more tubular halloysite.Spheroidal halloysite was found in a red soil and a paddy soil developed from olivine basalt gibbsite in the soils in this district was largely“primary gibbsite” which formed in the early weathering stage.Gibbsite decreased with the increase of weathering degree from yellow soil to red soil to lateritic red soil.Goethite also decreased in the same sequence while hematite increased.  相似文献   

9.
华南海岛土壤形成的地球化学   总被引:5,自引:0,他引:5  
The soils in South China sea Islands(SCSI)were divided into three types,nmaely,phospho-calc soils,skeletisols and coastic solonchake,which were derived from bio-clastic and strongly calcareous sediments.In comparison with their parent materials,the phospho-Calc soils have higher contents of P,Zn Cu,Ba,and Cd,which tend to increase gradually with time,and lower contents of Mg,Ca,Sr,B,V,Pb,and Mo,which tend to decrease by degrees with time,The above-mentioned constituents in skeletisols and coastic solonchaks are similar to those in their parent materials except for P and Na,The factors affecting element distribution are mainly special bioclimate and parent material,meanwhile,resulting in the remakable influence on element distribution through soil-forming time.  相似文献   

10.
土壤中氮磷钾肥转化中的交互作用: Ⅰ.土壤pH的动态变化   总被引:10,自引:0,他引:10  
Dynamic changes of soil pH as influenced by ammonium sulfate (AS), monocalcium phosphate (MCP),potassium chloride (KCl) and their interaction in soils were evaluated in incubation experiments. Applyingthese fertilizers significantly reduced soil pH values in all cases and followed sequences of AS > MCP >KCl, MCP > KCl > AS and KCl > AS > MCP for the paddy, calcareous and red soils, respectively. TheAS-induced reduction of pH in the three soils followed the sequence of red soil > paddy soil > calcareous soil,while in MCP and KCl systems the reduction of pH followed the sequences of calcareous soil > paddy soil >red soil and red soil > calcareous soil > paddy soil, respectively. The interactions of the NPK fertilizers on pHwere significant. MCP plus KCl or MCP plus AS reduced pH values more than the fertilizers applied solelyin the paddy soil, but AS partly counteracted the effect of MCP on pH in the 1 d sample of the calcareoussoil. The effect of MCP on pH was trivial when MCP was applied in combination with KCl or AS in the redsoil. When applied in combination with AS, KCl did not affect soil pH initially, but suppressed the reductionof pH at the later incubation stage, which was related to inhibition of nitrification by KCl in the soils.  相似文献   

11.
在山东省1∶100万SOTER数据库的支持下,运用土壤多样性理论及其测度方法对山东省不同地形单元上发育的土壤类型的多样性及其分布模式进行了初步的分析和定量化的研究。结果表明:土壤多样性指数从大到小依次为平原、中坡度、中坡度丘陵、山麓平原、中坡度峭壁带、低洼地和高坡度山地;土壤丰富度指数从高到低依次为平原、中坡度丘陵、中坡度、低洼地和山麓平原、中坡度峭壁带和高坡度山地;土壤均匀度指数从大到小依次为:中坡度、平原、山麓平原、中坡度丘陵、中坡度峭壁带、低洼地和高坡度山地。不同类型地形单元上发育的土壤的面积均不同程度地符合对数正态分布。  相似文献   

12.
基于PLSPM模型的鄂西南部分区域耕地土壤pH影响因素研究   总被引:2,自引:0,他引:2  
选用鄂西南部分区域采集的土壤pH数据,进行其影响因素研究。结果表明:研究区耕地土壤pH呈现东北向西南降低的趋势,整体属于酸性土壤;不同耕地类型土壤p H大小分别是:水浇地旱地水田;不同成土母质发育的土壤p H有所差异,碳酸盐岩发育的土壤p H较高,结晶岩和泥质岩发育的土壤p H较低;耕地土壤p H多因素综合模型显示,人为活动是该区耕地土壤p H的主要影响因素,其后依次是气候、作物和地形;不同土壤酸碱性的耕地对影响因素的响应程度存在差异,中性和弱碱性土壤对人为活动表现为正向响应,强酸性及弱酸性土壤对作物长势和地形同样表现为正向响应,极强酸性土壤对人为活动的响应程度最低,弱碱性土壤对气候的响应程度最强。  相似文献   

13.
The objective of the present investigation was to find out the effect of different parent materials and land use on soil erodibility. Four types of parent materials such as andesite, basalt, alluvial, and gypsum, and three land use types such as grass, clover, and maize, all wide spread in Erzurum Province in Turkey, were tested. Aggregate stability and soil erodibility factors were determined. The susceptibility of soils against erosion decreased in the order of parent materials basalt > andesite > alluvial > gypsum. Likewise, the susceptibility of land use can be sorted as follows: grass > clover > maize.  相似文献   

14.
Abstract

Six profiles, derived from Precambrian Basement Complex rocks (mainly gneiss), Cretaceous sediments (mainly shale and sandstone), and Quaternary alluvium, and which are typical of the major agricultural soils in the Lower Benue Valley (Nigeria) were studied with the objective to determine their overall potassium (K) reserves and any relationship between these and other soil properties including their parent materials. Total K in the soils varies from 0.13–27.1 g kg‐1 with average 6.64 g kg‐1. This correlates positively with the clay, and negatively with the sand contents of the soils and is also influenced by their parent materials. The order of abundance according to parent material is: alluvium‐ > Basement Complex (gneiss)‐ ≈ shale‐ > sandstone‐derived soils. The concentrations of readily available K (RAK) in the soils are quite low, accounting for only between 0.30 and 7.8% of the total K in the soils and less than 4.0% of their exchange capacities. Based on critical limits established for many Nigerian soils, the soils derived from sandstone are clearly deficient in RAK, while soils developed from gneiss, shale and alluvium parent materials have moderate to sufficient levels for a wide range of crops. Non‐exchangeable or moderately available K (MAK) in the soils is also relatively low (0.020–8.59 mmolc kg‐1); while the sandstone‐derived soils have the least MAK, the alluvial soils have the most levels. However, the potassium supplying power (KSP) of the soils may be considered to be generally high. Although this bears no particular relationship to soil parent materials, the sandstone‐derived soils have the lowest KSP. The bulk of the total K reserves in the soils (55–88%) exists as difficultly available or structural K (DAK). The alluvial soils first, then the gneiss‐ and shale‐derived soils next have the highest contents of DAK, while the highly weathered sandstone soils have the lowest. Simple correlation analysis shows that, irrespective of parent material and K form, clay content and CEC are the most important soil properties influencing the overall K supplying status of these soils. It is concluded that in major agricultural soils of the Lower Benue Valley of Nigeria K exists mostly in the lattice structures of K‐bearing minerals, with accumulations in the subsurface horizons. Its plant‐available or supplying status is low on sandstone‐derived soils and moderate to sufficient on soils derived from Basement Complex rocks, shales and alluvium.  相似文献   

15.
重庆紫色母岩及土壤As、Hg环境地球化学基线研究   总被引:5,自引:0,他引:5  
为了掌握紫色土类中As和Hg在不同发育阶段土壤中元素含量的理论值(基线值),在重庆市合川区系统采集侏罗系沙溪庙组(J2s)紫色母岩及其不同发育程度的各土种样品,利用土壤"钛值"法测定和验证土壤发育程度;通过对土壤全量As、Hg的测定,采用标准化方法,建立紫色土类中灰棕紫泥土属As、Hg的环境地球化学基线模型。结果表明:侏罗系沙溪庙组(J2s)紫色母岩发育的土壤As、Hg的环境地球化学基线均表现为随土壤发育加深而轻度累积,As基线值大小顺序为母岩石骨子土半沙半泥土大眼泥紫黄泥,而Hg的基线值大小顺序为母岩石骨子土半沙半泥土紫黄泥大眼泥;Hg在土壤发育过程中的富集程度约大于As;深度发育土中As和Hg的化学基线值分别为5.94 mg kg-1、29.0μg kg-1,可作为重庆地区中性紫色土亚类、灰棕紫泥土属土壤污染评价的参考。  相似文献   

16.
A standardized ultrasonic dispersion is presented with reference to soil structure. It is suggested that the parameters of aggregate stability can be expressed by the input of ultrasound energy which causes a soil-dependent process of aggregate dispersion. Preliminary results for soils of different land use and parent materials show that, for the soils examined, the stability of mesoaggregates (60–2,000 μm) lowers in the sequence forest > grassland > wasteland >arable land and limestone > basalt > loess > glacial till. Close correlations were also found to the content of carbon and clay.  相似文献   

17.
This study is based on a sequence of soils on a typical slope of the Himalayas in central Nepal from 2300 m to 4000 m. Above 2300 m the land is forested and at 4000 m forest gives way to alpine meadows.The soils have developed in silty loam materials derived from weathering of micaschists. They are humic, acid and strongly desaturated. Their spatial distribution is related to the bioclimatic zonation: acid brown soils and deep humic acid soils occur in the mountain zone and podzols and brown podzolic soils in the subalpine and alpine ones.Biological activity and “maturation” of humus decrease with increasing elevation. The podzolization process dominates. There is intense weathering of ferruginous phyllosilicates in eluvial horizons and accumulation of amorphous products in B horizons.  相似文献   

18.
广东省不同母质发育土壤颗粒分布的分形维数特征   总被引:6,自引:1,他引:5  
采集广东省主要成土母质(玄武岩、砂页岩、第四纪红土和花岗岩)发育的林地、耕地和园地土壤剖面各发生层土壤,测定了土壤颗粒组成、有机质、CEC等理化性质,探讨了不同母质发育土壤颗粒分布的分形维数特征及其与土壤理化性质的关系。结果表明,玄武岩、第四纪红土、花岗岩和砂页岩发育土壤分形维数变幅分别为2.923 9~2.981 2,2.858 8~2.937 7,2.769 3~2.923 1和2.544 6~2.885 6;玄武岩和第四纪红土发育土壤颗粒分布分形维数与砂页岩发育土壤存在显著差异。土壤颗粒分布的分形维数随土壤深度增加呈增大的趋势,相同母质发育土壤的深层土壤颗粒分布的分形维数接近一致。玄武岩和第四纪红土发育土壤颗粒分布的分形维数在不同深度土壤之间变幅较小,砂页岩和花岗岩发育土壤变幅较大。土壤颗粒分布的分形维数与砂粒含量呈极显负相关,与黏粒含量呈极显著正相关,与土壤全磷、速效钾、全铁、CEC、有机质、全氮、碱解氮呈极显著或显著正相关;土壤颗粒分布的分形维数可以作为表征土壤肥力状况指标。  相似文献   

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