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为全面了解宁夏山地土壤的发育特性及其系统分类归属,基于宁夏土系调查项目挖掘的典型剖面,选取10个发育在宁夏贺兰山山地(剖面编号为3、11、13、14和108)和六盘山山地(剖面编号为73、82、119、120和121)的土壤作为研究对象,结合剖面形态特征和理化性质,尝试对山地土壤的发育特征和系统分类归属进行研究。结果表明:(1)发育在宁夏的10个山地土壤高级单元归属为新成土、雏形土、淋溶土和均腐土等4个土纲,正常新成土、干润雏形土、湿润雏形土、冷凉淋溶土、湿润均腐土等5个亚纲,干旱正常新成土、简育干润雏形土、暗沃干润雏形土、冷凉湿润雏形土、简育冷凉淋溶土、斑纹湿润均腐土等6个土类,石灰干旱正常新成土、普通简育干润雏形土、普通暗沃干润雏形土、暗沃冷凉湿润雏形土、普通简育冷凉淋溶土、斑纹简育湿润均腐土等6个亚类,续分为10个土族,包括粗骨砂质硅质混合型温性—石灰干旱正常新成土,粗骨砂质长石型温性—石灰干旱正常新成土,壤质长石混合型石灰性冷性—普通简育冷凉淋溶土,砂质硅质混合型非酸性冷性—斑纹简育湿润均腐土等,10个供试剖面在土族完全分异,因而续分为10个土系,包括葡萄泉系、一堆系、滚钟口系、六盘山公园系、绿塬腰系等10个土系。(2)海拔对宁夏山地土壤的发育特征有着明显影响,表现为随海拔升高:腐殖质积累过程逐渐明显、土体淋溶过程加剧、土体石灰反应逐渐减弱直至消失;土壤水分条件逐渐改善,处于高海拔位置的山地土壤土体底部有弱氧化还原反应发生,形成铁子和铁锰胶膜;土壤pH逐渐减小,土壤酸碱性发生一定的变化。(3)受成土环境和成土因素的作用,土壤发育规律在诊断特征上的反映为随海拔高度的抬升呈现一定的垂直分异规律,其中诊断表层由淡薄表层演变为暗沃表层;土壤水分状况经干旱/半干润土壤水分状况向湿润土壤水分状况演化;土壤温度状况由温性土壤温度状况变为冷性状况。 相似文献
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河南省典型淋溶土土系划分研究 总被引:6,自引:0,他引:6
在河南省选取8个典型土壤剖面,对其进行景观特征、剖面形态学特征的描述及其理化性质的分析,并确定其在土壤系统分类(Chinese Soil Taxonomy)中的归属,结果表明,供试土壤归属于壤质混合型石灰性温性普通简育干润淋溶土、壤质混合型非酸性温性斑纹简育湿润淋溶土、黏壤质混合型温性斑纹钙积干润淋溶土、黏壤质混合型温性普通钙积干润淋溶土、壤质混合型石灰性温性普通简育湿润淋溶土和壤质混合型非酸性温性普通简育湿润淋溶土等6个土族;并在此土族基础上,根据土系划分规则和河南地区淋溶土诊断特征及构型特征,尝试提出"土系对比检索逻辑图"以阐述土系参比划分的逻辑过程。通过对比,可将8个典型土壤剖面划分为7个土系:汤阴系、汲水系、神沟系、尚庄系、侯集系、枣林系和尚店系。 相似文献
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为了明确陕西省烟叶主产区土壤类型归属,选取了陕西省烟叶适宜种植区中洛南县、陇县、旬阳县3个典型剖面,分别进行了野外观察描述土壤性状和室内测试土壤剖面各层次的基本理化性质。在研究了各取样地土壤形成条件和特点的基础上,按照《中国土壤系统分类检索(第3版)》,鉴定了诊断层和诊断特性,明确了供试土壤剖面在中国土壤系统分类中的归属。检索结果表明,陕西洛南、陇县、旬阳3个烟叶种植基地土壤分别为普通铁质湿润淋溶土、普通钙积干润均腐土、普通简育湿润淋溶土。同时与中国土壤发生分类进行了比较,以便于今后陕西省烟叶种植区对土壤系统分类的推广及利用,并为陕西省烟叶种植基地土壤规划利用和国际间土壤学术交流提供科学依据。 相似文献
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长期不同施肥措施下塿土细菌群落结构变化及其主要影响因素 总被引:2,自引:0,他引:2
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宁夏中部地区典型灰钙土的发育特性及系统分类研究 总被引:4,自引:0,他引:4
为了解宁夏中部地区地带性土壤——灰钙土的发育特性及其在中国土壤系统分类中的归属,在研究区内挖掘8个代表性的土壤剖面,进行剖面形态观察,采集分层土壤样品,测试理化性状。结果发现:(1)灰钙土中发生的主要成土过程有:弱腐殖质积累、弱淋溶淀积过程。(2)8个供试剖面中检索出的诊断依据有淡薄表层、干旱表层、雏形层、钙磐等诊断层,黄土和黄土状沉积物岩性特征、半干润/干旱土壤水分状况、温性土壤温度状况、钠质特性、石灰性等诊断特性和钙积诊断现象等。(3)依据《中国土壤系统分类检索(第三版)》,可将8个供试剖面初步归属为雏形土、干旱土2个土纲,干润雏形土、正常干旱土2个亚纲,简育干润雏形土和简育正常干旱土2个土类,普通简育干润雏形土、钠质简育正常干旱土2个亚类。依据《中国土壤系统分类土族与土系划分标准》将供试剖面初步划分为5个土族,5个土系。(4)参比研究表明,灰钙土在土壤发生分类和系统分类中的分类类别不是简单一对一的关系,发生分类中相同的类别可对应系统分类中不同类别,系统分类定量化的分类指标使土壤分类更加量化,减少了同名异土情况的发生,提高了分类的准确性。 相似文献
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为研究有机无机肥料配施对植烟土壤细菌群落结构的影响,采用Illumina MiSeq高通量测序技术,分析了连续3年施用化肥(CF)、烟草秸秆生物有机肥配施化肥(TBF)和高碳基土壤修复肥配施化肥(HCF)对土壤细菌多样性和群落结构的影响,同时结合土壤理化性质探究不同施肥条件下细菌群落变化的重要影响因素。与CF处理相比,HCF处理土壤碱解氮含量显著降低了34.09%。多样性指数分析显示有机无机肥料配施有提高土壤细菌多样性的趋势,HCF处理土壤细菌多样性最高。有机无机肥料配施提高了土壤放线菌门(Actinobacteria)、变形菌门(Proteobacteria)、酸杆菌门(Acidobacteria)、芽单胞菌门(Gemmatimonadetes)、拟杆菌门(Bacteroidetes)和浮霉菌门(Planctomycetes)细菌丰度,降低了土壤绿湾菌门(Chloroflexi)、Saccharibacteria、厚壁菌门(Firmicutes)、WD272和蓝细菌门(Cyanobacteria)细菌丰度。有机无机肥料配施显著增加了土壤Patulibacter、短芽孢杆菌属(Brevibacillus)、农研丝杆菌属(Niastella)等有益细菌属丰度。Spearman相关性分析和典范对应分析(CCA)表明土壤pH值、碱解氮和速效钾是影响土壤细菌群落结构的重要因子。有机无机肥料配施对植烟土壤细菌多样性和群落结构产生了深刻影响,土壤pH值、碱解氮和速效钾是调控细菌群落结构的重要影响因素,在土壤培肥中应引起充分的重视。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(6):367-375
Abstract Soil samples were obtained at 0–3, 3–6, 6–9 and 0–9 inch depths from experimental plots receiving five tillage treatments. Each of two samplers composited approximately six one‐inch cores from each plot. Soil samples were analyzed for acidity, P and K using routine analysis procedures in the University of Illinois Soil Testing Laboratory. Few significant differences were attributed to sampler and it was concluded that samplers using similar sampling techniques were obtaining soil samples from the same population. No significant differences in soil acidity at different depths were observed. The different tillage methods did significantly affect soil P at the 0–3 inch depth, but had no significant effect on soil P at deeper depths. Different tillage methods also significantly affected soil K values at different depths. 相似文献
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E. A. Mikhailova C. J. Post M. A. Schlautman J. M. Galbraith H. A. Zurqani 《Communications in Soil Science and Plant Analysis》2018,49(15):1826-1834
Soil textural information is an important component underlying other soil health indicators. Soil texture analysis is a common procedure, but it can be labor intensive and expensive. Soil texture data typically are available from the Soil Survey Geographic (SSURGO) database, which may be an option for determining soil health texture groups (SHTG). The SSURGO database provides soil texture information in the soil map unit (SMU) name, taxonomic class category (family), and detailed values (≤ 2 mm soil fraction) of percent sand, silt and clay by soil horizon. The objective of this study was to examine the possibility of using SSURGO data for SHTG at the 147-ha Cornell University Willsboro Research Farm in New York state as an alternative for soil texture data determined manually on collected soil core samples. Comparative results revealed that representative values for soil texture from the SSURGO database generally matched measured mean values for all SMUs. 相似文献
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土壤含水率与土壤碱度对土壤抗剪强度的影响 总被引:11,自引:11,他引:11
土壤含水率和土壤碱度是表征土壤物理化学性质的两个重要参数。通过室内三轴不固结不排水试验,研究了土壤含水率和土壤碱度对土壤抗剪强度的影响。试验处理采用5种土壤碱度(土壤可交换钠百分比ESP=0、5、10、20、40)和4种土壤质量含水率(0.05、0.10、0.20以及饱和含水率0.34)水平。试验结果显示,土壤黏聚力随着土壤含水率的增加基本上呈先增大后减小之趋势;当土壤含水率在0.10附近时黏聚力达到其最大值。土壤内摩擦角随着土壤含水率的增加而线性减小。土壤碱度对土壤黏聚力的影响机理较为复杂,其影响效果随土壤含水率的增加而减小;但土壤碱度对土壤内摩擦角的影响较小。土壤碱度对土壤抗剪强度的影响程度明显地小于土壤含水率对其的影响程度。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(6):567-571
Abstract The design, materials and dimensions for constructing a coring device for sampling soil fauna and flora at different depths is described. 相似文献
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The interaction of soil microbes with their physical environment affects their abilities to respire, grow and divide. One of these environmental factors is the amount of moisture in the soil. The work we published almost 25 years ago showed that microbial respiration was linearly related to soil-water content and log-linearly related to water potential. The paper arose out of collaboration between two young researchers from different areas of soil science, physics and microbiology. The project was driven by not only our curiosity but also the freedom to operate without the constraints common to the current system of science management. The citation history shows three peaks, 1989, 1999 and from 2002 to the present day. Interestingly, the annual citation rate is as high as it has ever been. The initial peak is due to the application of the work to studies on microbial processes. The second peak is associated with the rise of simulation modelling and the third with the relevance of the findings to climate change research. In this article, our paper is re-evaluated in the light of subsequent studies that allow the principle of separation of variables to be tested. This re-evaluation lends further credence to the linear relationship proposed between soil respiration and water content. A scaled relationship for respiration and water content is presented. Lastly, further research is suggested and more recent work on the physics of gas transport discussed briefly. 相似文献
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Microbial activity is affected by changes in the availability of soil moisture. We examined the relationship between microbial activity and water potential in a silt loam soil during four successive drying and rewetting cycles. Microbial activity was inferred from the rate of CO2 accumulating in a sealed flask containing the soil sample and the CO2 respired was measured using gas chromatography. Thermocouple hygrometry was used to monitor the water potential by burying a thermocouple in the soil sample in the flask. Initial treatment by drying on pressure plates brought samples of the test soil to six different water potentials in the range -0.005 to -1.5MPa. Water potential and soil respiration were simultaneously measured while these six soil samples slowly dried by evaporation and were remoistened four times. The results were consistent with a log-linear relationship between water potential and microbial activity as long as activity was not limited by substrate availability. This relationship appeared to hold for the range of water potentials from ?0.01 to ?8.5 MPa. Even at ?0.01 MPa (wet soil) a decrease in water potential from ?0.01 to ?0.02 MPa caused a 10% decrease in microbial activity. Rewetting the soil caused a large and rapid increase in the respiration rate. There was up to a 40-fold increase in microbial activity for a short period when the change in water potential following rewetting was greater than 5 MPa. Differences in microbial activity between the wetter and drier soil treatments following rewetting to the original water potentials are discussed in terms of the availability of energy substrate. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(7):833-840
Abstract The design, dimensiors and materials for constructing volumetric soil measures for routine soil testing use are presented. Scoop calibration techniques are also described. Reproducibility of results obtained under routine laboratory, conditions are shown. The measures include volumes of 1.0‐, 2.5‐, 5.0‐ and 10‐ cm3 respectively. 相似文献
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《CATENA》1998,32(1):15-22
Evaluation of various soil erosion models with large data sets have consistently shown that these models tend to over-predict soil erosion for small measured values, and under-predict soil erosion for larger measured values. This trend appears to be consistent regardless of whether the soil erosion value of interest is for individual storms, annual totals, or average annual soil losses, and regardless of whether the model is empirical or physically based. The hypothesis presented herein is that this phenomenon is not necessarily associated with bias in model predictions as a function of treatment, but rather with limitations in representing the random component of the measured data within treatments (i.e., between replicates) with a deterministic model. A simple example is presented, showing how even a `perfect' deterministic soil erosion model exhibits bias relative to small and large measured erosion rates. The concept is further tested and verified on a set of 3007 measured soil erosion data pairs from storms on natural rainfall and run-off plots using the best possible, unbiased, real-world model, i.e., the physical model represented by replicated plots. The results of this study indicate that the commonly observed bias, in erosion prediction models relative to over-prediction of small and under-prediction of large measured erosion rates on individual data points, is normal and expected if the model is accurately predicting erosion rates as a function of environmental conditions, i.e., treatments. 相似文献
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Soil hydraulic properties play a crucial role in simulating water flow and contaminant transport. Soil hydraulic properties are commonly measured using homogenized soil samples. However, soil structure has a significant effect on the soil ability to retain and to conduct water, particularly in aggregated soils. In order to determine the effect of soil homogenization on soil hydraulic properties and soil water transport, undisturbed soil samples were carefully collected. Five different soil structures were identified: Angular-blocky, Crumble, Angular-blocky (different soil texture), Granular, and subangular-blocky. The soil hydraulic properties were determined for undisturbed and homogenized soil samples for each soil structure. The soil hydraulic properties were used to model soil water transport using HYDRUS-1D.The homogenized soil samples showed a significant increase in wide pores (wCP) and a decrease in narrow pores (nCP). The wCP increased by 95.6, 141.2, 391.6, 3.9, 261.3%, and nCP decreased by 69.5, 10.5, 33.8, 72.7, and 39.3% for homogenized soil samples compared to undisturbed soil samples. The soil water retention curves exhibited a significant decrease in water holding capacity for homogenized soil samples compared with the undisturbed soil samples. The homogenized soil samples showed also a decrease in soil hydraulic conductivity. The simulated results showed that water movement and distribution were affected by soil homogenizing. Moreover, soil homogenizing affected soil hydraulic properties and soil water transport. However, field studies are being needed to find the effect of these differences on water, chemical, and pollutant transport under several scenarios. 相似文献