小兴安岭典型森林土壤中外源丙氨酸的潜在周转差异  

Potential turnover differences of exogenous alanine in soils of typical forests in the Xiaoxing’an Mountains,China

作　　者：郝静 郭亚芬[1] 高雷 HAO Jing;GUO Ya-fen;GAO Lei(School of Forestry,Northeast Forestry University,Harbin 150040,China;School of Forestry,Beihua University,Jilin 132013,Jilin,China)

机构地区：[1]东北林业大学林学院,哈尔滨150040 [2]北华大学林学院,吉林吉林132013

出　　处：《应用生态学报》2022年第12期3237-3244,共8页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31370617)资助。

摘　　要：以小兴安岭白桦林、蒙古栎林、白桦+红松+五角槭混交林、红松林和长白落叶松林5种典型森林为对象,研究林型(阔叶林、混交林、针叶林)和土层(0~10、10~20和20~30 cm)对土壤中外源丙氨酸周转的影响。结果表明:外源丙氨酸在不同林型土壤中的周转存在时间差异和剖面异质性,总体表现为阔叶林周转较快,混交林次之,针叶林最慢,外源丙氨酸在3种林型的半衰期依次为2.6~4.2、3.6~5.5和4.3~7.0 h。随着土层的加深,各林型外源丙氨酸的潜在周转速度均变慢,半衰期变长,土壤对丙氨酸的吸附性变弱。加入外源丙氨酸后,阔叶林、混交林、针叶林的铵态氮和硝态氮含量显著增加,铵态氮分别增加了83.8%~95.3%、80.9%~94.6%和73.7%~93.2%,硝态氮分别增加了82.9%~94.7%、82.3%~93.8%和78.1%~92.5%。不同林型土壤净氨化作用速率和净硝化作用速率均呈先激增后缓慢降低的趋势,且均为正值。土层和林型及二者交互作用均显著影响外源丙氨酸的周转、半衰期、氨化作用、硝化作用。Taking five typical forests(Betula platyphylla forest,Quercus mongolica forest,B.platyphylla+Pinus koraiensis+Acer mono mixed forest,P.koraiensis forest,and Larix olgensis forest)in Xiaoxing’an Mountains as test objects,we investigated the effects of forest types(broadleaved forest,mixed forest,and coniferous forest)and soil layers(0-10 cm,10-20 cm,20-30 cm)on the turnover of exogenous alanine.The results showed that the turnover of soil exogenous alanine varied across different forest types,with significant difference in time and profile.The turnover rate was the highest in the broadleaved forest,followed by the mixed forest,and the lowest in the coniferous forest,with the half-life being 2.6-4.2,3.6-5.5,and 4.3-7.0 h,respectively.With increasing soil depth,the potential turnover rate of exogenous alanine decreased,the half-life became longer,and soil adsorption of alanine weakened.With the addition of exogenous alanine,the content of ammonium and nitrate significantly increased,with the former being increased by 83.8%-95.3%,80.9%-94.6%and 73.7%-93.2%,and the latter being increased by 82.9%-94.7%,82.3%-93.8%and 78.1%-92.5%in the broadleaved forest,mixed forest,and coniferous forest,respectively.The net ammoniation and nitrification rates increased sharply at first and then decreased slowly,which were both positive.Soil layer and forest type as well as their interaction significantly affected the turnover,half-life,ammoniation,and nitrification of exogenous alanine.

关 键 词：外源丙氨酸 周转 半衰期 氨化作用 硝化作用 

分 类 号：S714[农业科学—林学]