摘要
【目的】研究不同海拔下草地表层土壤养分和酶活性的变化特征。【方法】以祁连山西段的天然草地为研究对象,分析了不同海拔(2 995、3 170、3 403、3 620、3 817、4 068 m)表层土壤养分含量、生态化学计量比和酶活性的变化特征。【结果】海拔对草地表层土壤养分和酶活性具有显著影响;随着海拔的升高,土壤pH值、Cu含量呈上升趋势,土壤有机碳、全氮、全磷、N/P比、脲酶活性、碱性磷酸酶活性、过氧化氢酶活性、Zn含量、Mg含量呈先升高后降低,土壤C/N比、C/P比、Fe含量呈先下降后上升,但各指标最小值和最大值出现的海拔梯度各异;不同海拔N/P比处于3.58~5.86,均小于10;基于冗余分析(RDA)发现土壤有机碳和全磷是影响土壤酶活性的关键养分因子。【结论】草地表层土壤养分和酶活性随不同海拔高度呈规律性分布,且生产力主要受氮素的限制。建议依据海拔差异制定合理的管理措施,促进草地生态的健康发展。
【Objective】The aim of the study is to investigate the characteristics changes of soil nutrients and en-zyme activities in surface layer soil of grassland at different altitudes.【Method】In this research,the natural grassland in the middle of Qilian Mountains was used as the research object,and characteristics changes of soil nutrient content,ecological stoichiometry ratio and enzyme activity at different altitudes(2995 m,3170 m,3403 m,3620 m,3817 m and 4068 m)were analyzed.【Result】The research showed that altitude had significant effects on the nutrient and en-zyme activities of the grassland surface soil.With the increase of altitude,soil pH and Cu content showed an increas-ing trend,while soil organic carbon,total N,total P,N/P ratio,urease activity,alkaline phosphatase activity,peroxi-dase activity,Zn content and Mg content first increased and then decreased.Soil C/N ratio,C/P ratio and Fe content decreased first and then increased.However,the minimum and maximum values of each index occurred in different al-titude gradients.Meanwhile,the N/P ratios in different altitude were 3.58~5.86,and were all less than 10,which meant that grassland productivity was limited by nitrogen.Based on RDA analysis it could be found that soil organic carbon and total phosphorus were the key nutrient factors affecting soil enzyme activity.【Conclusion】The soil nutri-ents and enzyme activities in the surface layer of grassland showed regular distribution with altitude,and the productiv-ity was mainly limited by nitrogen.It is suggested that reasonable management measures should be formulated accord-ing to altitude differences to promote the healthy development of grassland ecology.
作者
李强
张英
李晓晴
柳小妮
张德罡
LI Qiang;ZHANG Ying;LI Xiao-qing;LIU Xiao-ni;ZHANG De-gang(State Key Laboratory of Ecology of Sanjiangyuan and Plateau Agriculture and Animal Husbandry,College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China;College of Grassland,Gansu Agricultural University,Lanzhou 730000,China)
出处
《草原与草坪》
CAS
CSCD
2024年第4期26-33,共8页
Grassland and Turf
基金
青海大学省部共建国家重点实验室自主项目(2023-ZZ-05)
国家重点研发计划项目(2021YFC3201604)。
关键词
祁连山中段
土壤养分
酶活性
海拔
Qilian Mountains
enzyme activity
soil nutrients
altitude
