中南地区典型地带性土壤团聚体抗张强度的变化及影响因素

发布时间：2018-08-21 10:03

【摘要】：团聚体的力稳性是决定土壤抗侵蚀能力的关键因素。为探究地带性土壤团聚体抗张强度的变化规律及其影响因素,自北向南选取我国中南部地区6种典型地带性土壤(褐土、黄褐土、棕红壤、红壤、赤红壤和砖红壤)的不同粒径(1~2,2~3,3~5,5~10mm)团聚体作为研究对象,通过测定团聚体的抗张强度(TS),探究其与土壤基本理化性质的关系,揭示该区域团聚体抗张强度的变化特点和稳定机制。结果表明:(1)供试土壤皆为黏性土壤,自北向南,随着水热条件的增加,土壤的pH值逐渐降低,高岭石含量和游离氧化物(Fe_d、Al_d)呈现明显的增加趋势;有机质含量随土壤深度的增加而降低。(2)同种土壤团聚体的抗张强度随着粒径的增大而逐步减小,从北至南,相同粒径团聚体的抗张强度整体呈现减小的趋势。(3)TS与pH、粉粒含量、蛭石含量呈极显著正相关(r0.63,p0.01),TS与黏粒含量、1.4nm过渡矿物含量、高岭石含量、游离氧化铁、铝(Fe_d、Al_d)呈显著负相关(r-0.53,p0.05)。(4)逐步回归分析表明,Fe_d和CEC可以较好的预测和评价3~5mm团聚体的抗张强度(R~2=0.80,p0.01)。总体而言,黏土矿物类型及其含量是影响地带性土壤团聚体力稳性的重要因素。研究结果可为该区域土壤侵蚀预测提供一定的理论依据。
[Abstract]:The force stability of aggregate is the key factor to determine soil erosion resistance. In order to investigate the variation of tensile strength of zonal soil aggregates and its influencing factors, six typical zonal soils (cinnamon soil, yellow cinnamon soil, brown red soil) were selected from north to south of China. The aggregates of different particle sizes (1 ~ 2 ~ 2 ~ 3 ~ 3 ~ 3 ~ 5 ~ 5 ~ 5 ~ 5 ~ 5 ~ 10 mm) of lateritic red soil and latosol were studied. The relationship between the tensile strength of the aggregate and the basic physical and chemical properties of the soil was investigated by measuring the tensile strength of the aggregates, and the characteristics of the tensile strength and the mechanism of stability of the aggregates in the region were revealed. The results showed that: (1) all the tested soils were clay soils, from north to south, with the increase of water and heat conditions, the pH value of the soil gradually decreased, and the kaolinite content and free oxide (FeD Ald) showed an obvious increasing trend; The content of organic matter decreased with the increase of soil depth. (2) the tensile strength of the same soil aggregates gradually decreased with the increase of particle size. From north to south, the tensile strength of the same size aggregates decreased as a whole. (3) TS, pH, silt content, Vermiculite content was positively correlated with clay content at 1.4nm transition mineral content, kaolinite content, free iron oxide, aluminum (FednAld). Stepwise regression analysis showed that Fetid and CEC could predict and evaluate the tensile strength of 3~5mm aggregates (r-0.53p0.05). (_ 4). In general, clay mineral types and their contents are important factors affecting the physical stability of zonal soil agglomeration. The results can provide some theoretical basis for the prediction of soil erosion in this region.
【作者单位】：华中农业大学资源与环境学院农业部长江中下游耕地保育重点实验室;
【基金】：国家自然科学基金项目(41471231,41630858)
【分类号】：S152.4

【相似文献】