柴达木盆地不同盐化土壤粒级组成及可蚀性  

Particle size distribution and erodibility of soils under different salinization levels in the Qaidam Basin

作　　者：王鸿霞 操一芸 宋明丹 塔林葛娃 王乾冰[1] 刘承琦 李月梅 WANG Hongxia;CAO Yiyun;SONG Mingdan;Talin Gewa;WANG Qianbing;LIU Chengqi;LI Yuemei(Qinghai University,Xining 810016,China;Academy of Agriculture and Forestry Sciences,Qinghai University,Xining 810016,China;National Agricultural Environment Xining Observation Experimental Station,Xining 810016,China)

机构地区：[1]青海大学,西宁810016 [2]青海大学农林科学院,西宁810016 [3]国家农业环境西宁观测实验站,西宁810016

出　　处：《应用与环境生物学报》2024年第6期1101-1107,共7页Chinese Journal of Applied and Environmental Biology

基　　金：第二次青藏高原综合科学考察研究项目(2019QZKK0303);青海省重大科技专项(2023-NK-A3)资助。

摘　　要：柴达木盆地属封闭性的巨大山间断陷盆地,盆地土壤盐化程度较高,研究盐化土壤粒级组成、分形特征及土壤全盐量对土壤可蚀性的影响,可以为该区域盐化土壤改良和土壤侵蚀的精准防控提供科学依据.基于EPIC模型估算柴达木盆地地区可蚀性因子K值,并结合分形理论探究不同盐化土壤全盐量、粒级组成、土壤有机碳等要素对K值的影响.结果显示:(1)柴达木盆地表层土壤粒级以粉粒(64%-84%)和砂粒(14%-35%)为主,土壤质地以粉土和粉壤土为主.随着盐化程度的增加,土壤颗粒和质地逐渐变细,有机碳含量呈下降趋势.(2)研究区不同盐化土壤平均分形维数D的变化范围为2.38-2.55,可蚀性因子K值介于0.050和0.059之间,总体存在较高的侵蚀风险,且随盐化程度增加,分形维数D和可蚀性因子K值呈上升趋势,即土壤盐分的积累会增加土壤侵蚀风险.(3)可蚀性因子K值与黏粒、粉粒体积分数及全盐量呈正相关,与砂粒体积分数和土壤有机碳含量呈显著负相关.逐步回归方程结果表明对可蚀因子的影响从大到小依次为粉粒体积分数、土壤有机碳、分形维数D和全盐量.综上,柴达木盆地不同盐化土壤粒级分形特征差异明显,土壤可蚀性受环境因素影响而较高,建议利用秸秆还田改良土壤和合理调控土壤颗粒配比.The Qaidam Basin is a large,closed mountain discontinuous basin with a high degree of soil salinization.Understanding the effects of grain composition,fractal characteristics,and the total salt content of salinized soil on erodibility can provide a scientific basis for the improvement of salinized soil and the prevention and control of soil erosion in this region.This study estimated the K value of erodibility factor in the Qaidam basin based on the erosion-productivity impact calculator(EPIC)model,and combined with fractal theory,explored the effects of different salinized soil total salt content,grain composition,soil organic carbon,and other factors on K value.The results showed that:(1)The surface soil in the Qaidam Basin was mainly composed of silt(64%-84%)and sand(14%-35%),and the soil texture was mainly silt and silty loam.With an increase in the salinization degree,the soil particles and texture gradually became finer,and the organic carbon content showed a decreasing trend.(2)The average fractal dimension D of different salinized soils in the study area ranged from 2.38 to 2.55,and the value of erodibility factor K was between 0.050 and 0.059.The overall erosion risk was high,and the fractal dimension D and erodibility factor K showed an upward trend with the increase of salinization degree,that is,the accumulation of soil salt would increase the soil erosion risk.(3)The erodibility factor K was positively correlated with clay,silt volume fraction,and total salt content,and negatively correlated with sand volume fraction and soil organic carbon content.The stepwise regression results highlighted the order of factors influencing erodibility:powder volume fraction,soil organic carbon,fractal dimension D,and total salt content.These findings indicate that the fractal characteristics of different salinized soil grain sizes in the Qaidam Basin are significantly different,and soil erodibility is highly affected environmental factors.Suggestions are proposed that Straw returning to improve the soil and reasonab

关 键 词：盐化 分形维数 粒级组成 土壤可蚀性 柴达木盆地 

分 类 号：S152.4[农业科学—土壤学]