晋西北柠条长期种植对根系分布及土壤水碳的影响  

Impact of Long-Term Caragana korshinskii Plantation on Root Distribution and Soil Water-Carbon Dynamics in Northwestern Shanxi

作　　者：杨璐 刘小芳 张秀敏 巨佳敏 常富强 杨泽芃 赵勇钢[1] Yang Lu;Liu Xiaofang;Zhang Xiumin;Ju Jiamin;Chang Fuqiang;Yang Zepeng;Zhao Yonggang(College of Life Sciences,Shanxi Normal University,Taiyuan 030031,China)

机构地区：[1]山西师范大学生命科学学院,太原030031

出　　处：《水土保持研究》2024年第6期199-206,212,共9页Research of Soil and Water Conservation

基　　金：国家自然科学基金(42007064);山西省研究生教育创新项目(2022Y486);山西省自然科学基金面上项目(202203021221133)。

摘　　要：[目的]探究晋西北不同种植年限人工柠条深层土壤水碳和根系的相互作用,为黄土丘陵区人工植被恢复提供一定的理论基础。[方法]以不同种植年限(20,40,60 a)柠条林为研究对象,对0—300 cm土层水分、有机碳和根系特征参数进行测定,分析了三者的相互关系。[结果](1)相较于荒草地,柠条长期种植(大于40 a),降低了剖面土壤水分含量,但增加了剖面土壤有机碳含量。土壤水分亏缺现象主要集中在0—60,200—300 cm土层中,而有机碳含量主要分布在0—60 cm土层中。柠条种植显著增加了0—60 cm剖面根系特征参数,其根系生物量占0—300 cm土层的50%。(2)在0—60 cm土层,有机碳与土壤水分显著负相关(p<0.01),与根体积密度显著正相关(p<0.05);在60—200 cm土层,土壤水分与有机碳、根表面积密度和根体积密度显著负相关(p<0.05);在200—300 cm土层,土壤水分与根系参数均显著正相关(p<0.05)。多元回归和通径分析结果表明根体积密度和土壤水分是影响有机碳的主要因素,较高的根体积密度和较低的土壤水分有助于增加土壤有机碳。[结论]晋西北黄土丘陵区长期种植柠条后,对表层根系特征参数的增加促进了土壤有机碳积累,但加剧了表层土壤水分消耗,并促使根系向深层生长以适应水分条件。在区域进行植被建设时有必要综合考虑植被种植年限和土层深度对土壤水分、有机碳和根系特征的综合影响。[Objective]This study aims to explore the interaction between deep soil water,carbon and roots of artificial Caragana korshinskii with different planting years in northwest Shanxi Province,and to provide a theoretical basis for artificial vegetation restoration in the loess hilly region.[Methods]Caragana korshinskii forests with different planting years(20,40,60 years)were used as the research objects.The water content,organic carbon and root characteristic parameters of the 0—300 cm soil layer were measured,and the relationship between the three was analyzed.[Results](1)Compared to barren grasslands,long-term Caragana korshinskii cultivation(over 40 years)reduced soil moisture content across the profile while increasing soil organic carbon content.The deficit in soil moisture primarily occurred at depths of 0—60 cm and 200—300 cm,whereas the organic carbon content was predominantly distributed within the 0—60 cm depth.Caragana korshinskii planting significantly enhanced root characteristic parameters within the 0—60 cm profile,with root biomass accounting for 50% of the total in the 0—300 cm soil layer.(2)Within the 0—60 cm soil layer,organic carbon exhibited a significant negative correlation with soil moisture(p<0.01)and a positive correlation with root volume density(p<0.05);in the 60—200 cm layer,soil moisture showed a significant negative correlation with organic carbon,root surface area density,and root volume density(p<0.05);in the 200—300 cm layer,soil moisture was significantly correlated positively with root parameters(p<0.05).Multivariate regression and path analysis indicated that root volume density and soil moisture were principal factors influencing organic carbon,with higher root volume density and lower soil moisture contributing to an increase in soil organic carbon.[Conclusion]After long-term planting of Caragana korshinskii in the loess hilly area of northwest Shanxi,the increase in surface root characteristic parameters promoted soil organic carbon accumulation,but aggravat

关 键 词：柠条林 根系特征参数 水分亏缺效应 土壤有机碳 

分 类 号：S154.4[农业科学—土壤学]