哈溪林区土壤氮矿化随海拔植被变化特征  

Characteristics of Soil Nitrogen Mineralization Changes with Altitude Vegetation in Haxi Forest Region of Qilian Mountain

作　　者：张恒平 张富[1] 车宗玺 顾玉梅 ZHANG Hengping;ZHANG Fu;CHE Zongxi;GU Yumei(Forestry College of Gansu Agricultural University,Lanzhou 730070,China;Gansu Qilian Mountain National Nature Reserve Administration,Zhangye Gansu 73400,China;Haxi People’s Government,Tianzhu Gansu 733206,China)

机构地区：[1]甘肃农业大学林学院,甘肃兰州730070 [2]甘肃祁连山国家级自然保护区管理局,甘肃张掖734000 [3]天祝藏族自治县哈溪镇人民政府,甘肃天祝733206

出　　处：《甘肃林业科技》2020年第3期1-5,共5页Journal of Gansu Forestry Science and Technology

基　　金：国家自然科学基金“祁连山土壤氮矿化特征及分异规律研究”(31260141)。

摘　　要：土壤氮矿化过程决定陆地生态系统的初级生产力。采用顶盖埋管培养法,研究了祁连山哈溪林区不同植被类型、不同海拔梯度的土壤氮矿化特征。结果表明:1)青海云杉林土壤氮矿化量高于草地近一个数量级;2)青海云杉林土壤氮矿化量在海拔2800 m处最大为156.77 mg/(kg·a),2900 m处最小为92.60 mg/(kg·a),相对矿化能力在海拔2900 m处最强;3)草地土壤氮矿化量在海拔2900~3000 m处最大为19.16~20.66 mg/(kg·a),2800 m处最小为2.15 mg/(kg·a),相对矿化能力在海拔3000 m处最强;4)青海云杉林土壤氮铵化过程在海拔3100 m处最强,硝化过程在海拔2800 m处最强;5)草地土壤氮铵化过程在海拔3000 m处最强,硝化过程在海拔2900 m处最强。研究表明:海拔梯度相同时,青海云杉林土壤氮矿化以及铵化、硝化过程均显著强于草地;植被类型相同时,土壤氮绝对矿化与相对矿化、铵化、硝化能力随海拔变化过程各不相同。The process of soil nitrogen mineralization determines the primary productivity of terrestrial ecosystems.The soil nitrogen mineralization characteristics of different vegetation types and different altitude gradients in different vegetation types and different altitude gradients in the Haxi forest area of Qilian Mountains were studied using the method of burying the tube under the roof.The results show that:1)The soil nitrogen mineralization of Picea crassifolia forest is nearly an order of magnitude higher than that of grassland;2)The soil nitrogen mineralization of Picea crassifolia forest was 156.77 mg/(kg·a)at 2800 m and 92.60 mg/(kg·a)at 2900 m,and the relative mineralization capacity was the strongest at 2900 m;3)The maximum amount of nitrogen mineralization in grassland soil is 19.16~20.66 mg/(kg·a)at an altitude of 2900~3000 m,and the minimum is 2.15 mg/(kg·a)at an altitude of 2800 m.The mineralization capacity is strongest at an altitude of 3000 m;4)The ammonium nitrification process of Picea crassifolia forest soil is strongest at an altitude of 3100 m,and the nitrification process is strongest at an altitude of 2800 m;5)The nitrogen ammonium process of grassland soil is strongest at an altitude of 3000 m,and the nitrification process is strongest at an altitude of 2900 m.Research shows that when the altitude gradient is the same,the soil nitrogen mineralization,ammonium and nitrification processes of Picea crassifolia forest are significantly stronger than grassland;when the vegetation type is the same,the absolute mineralization,relative mineralization,ammonium and nitrification capacity of soil nitrogen varies with altitude the process of change varies.

关 键 词：祁连山 土壤氮矿化 青海云杉林 草地 海拔 

分 类 号：S714.2[农业科学—林学]