陇中黄土高原不同土地利用方式对土壤氮组分及酶活性的影响  

Effects of different land use practices on soil N fractions and enzyme activities in the Loess Plateau of Longzhong

作　　者：郭疆 袁建钰 卓玛草 闫丽娟[3] 姚武扬眉 杜梦寅 李广[1] GUO Jiang;YUAN Jianyu;Zhuomacao;YAN Lijuan;YAO Wuyangmei;DU Mengyin;LI Guang(College of Forestry,Gansu Agricultural University,Lanzhou 730070,China;College of Geology and Jewelry,Lanzhou Resources and Environment University Voc-Tech,Lanzhou 730000,China;College of Agronomy,Gansu Agricultural University,Lanzhou 730070,China)

机构地区：[1]甘肃农业大学林学院,甘肃兰州730070 [2]兰州资源环境职业技术大学地质与珠宝学院,甘肃兰州730000 [3]甘肃农业大学农学院,甘肃兰州730070

出　　处：《甘肃农业大学学报》2024年第6期186-194,共9页Journal of Gansu Agricultural University

基　　金：甘肃省优秀博士生项目(22JR5RA843);甘肃省科技厅青年科技基金项目(20JR10RA493);甘肃省优秀研究生“创新之星”项目(2022CXZX-641);甘肃省重点研发计划项目(22YF7FA116);甘肃省产业支持计划项目(2021CYZC-15)。

摘　　要：【目的】为探究陇中黄土高原土壤氮组分和酶活性在不同土地利用方式下的分布特征和变化规律。【方法】以陇中黄土高原地区5种不同土地利用方式(撂荒地、云杉林地、沙棘林地、苜蓿地、小麦地)条件下的土壤为研究对象,测定和分析了土壤氮组分含量以及土壤酶活性的变化特征。【结果】在5种土地利用方式下,0~60cm土层中云杉林地显著增加了土壤全氮和微生物量氮含量,撂荒地和小麦地相对较低。土壤铵态氮和硝态氮含量均在苜蓿地达到最高。此外,土壤氮组分含量在土层间也存在差异,其含量分布随土层深度增加而降低。除亚硝酸还原酶活性随土层深度增加表现为上升外,土壤脲酶、蛋白酶、硝酸还原酶活性随土层加深而降低。与撂荒地相比0~60cm土层云杉林地和沙棘林地土壤脲酶活性显著增加,苜蓿地和小麦地则有所下降。蛋白酶活性以云杉林地最优,撂荒地最低。苜蓿地硝酸还原酶活性最高,云杉和沙棘林地次之,小麦地最低。亚硝酸还原酶活性在不同土地利用方式中由强到弱依次为苜蓿地、撂荒地、沙棘林地、云杉林地、小麦地。相关性分析表明,土壤氮组分与酶活性之间存在一定的显著正相关关系(P<0.05)。【结论】土地利用方式是影响土壤氮素含量和酶活性变化的重要因素,土壤氮素含量增加,相关土壤酶活性也会升高,尤以云杉林地和苜蓿地表现最佳。【Objective】To study the distribution characteristics of nitrogen and enzyme activities in soils of the Longzhong Loess Plateau due to land use change and the effects on regional soil quality and microen-vironmental changes.【Method】Soils from five different land uses(abandoned land,spruce woodland,sea buckthorn woodland,alfalfa land,and wheat land)in the Loess Plateau area of Longzhong were used as re-search objects to determine and analyze the content of soil nitrogen fractions and the characteristics of changes in soil enzyme activity.【Result】Among the five land use approaches,spruce woodlands in the 0~60 cm soil layer significantly increased soil total and microbial nitrogen contents,while the abandoned land and wheat land had relatively low content.Soil ammonium and nitrate nitrogen contents were both highest in the alfalfa field.In addition,the content of soil N fractions varied between soil layers,its content distribu-tion decreases with increasing soil depth.Soil urease,protease and nitrate reductase activities decreased with soil depth,except for nitrite reductase activity which showed an increase with soil depth.Soil urease ac-tivity increased significantly in spruce woodland and buckthorn woodland in the 0~60 cm soil layer com-pared with the abandoned land,and decreased in alfalfa and wheat land.The protease activity was optimal in spruce woodland and lowest in abandoned land.Nitrate reductase activity was highest in alfalfa land,fol-lowed by spruce and buckthorn woodland,lowest in wheat land.The nitrite reductase activity in the differ-ent land use patterns from strong to weak was in the order of alfalfa land,abandoned land,sea buckthorn woodland,spruce woodland,and wheat land.Correlation analysis showed that there was some significant positive correlation between soil N fraction and enzyme activity(P<0.05).【Conclusion】Land use was an important factor influencing soil nitrogen content and soil enzyme activities,with an increase in soil nitrogen content,soil enzyme activities would also i

关 键 词：土地利用方式 陇中黄土高原 土壤氮组分 土壤酶活性 

分 类 号：S153[农业科学—土壤学]