模拟氮沉降对油松林土壤有机碳和全氮的影响  

Effects of simulated nitrogen deposition on soil organic carbon and total nitrogen content in plantation and natural forests of Pinus tabuliformis

作　　者：汪金松[1,2] 赵秀海[1] 张春雨[1] 李化山[1] 王娜[1] 赵博[1] 

机构地区：[1]北京林业大学森林资源与生态系统过程北京市重点实验室 [2]中国林业科学研究院森林生态环境与保护研究所

出　　处：《北京林业大学学报》2016年第10期88-94,共7页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(31340022)

摘　　要：本文通过长期原位模拟氮沉降试验,研究暖温带油松林土壤有机碳和全氮对外源氮添加的响应过程与机制。从2009至2011年,氮处理水平分别为对照（0 kg/（hm2·a）,N0）,低氮（50 kg/（hm2·a）,N1）,中氮（100 kg/（hm2·a）,N2）和高氮（150 kg/（hm2·a）,N3）。利用土钻法研究油松人工林和天然林不同土壤深度土壤有机碳和全氮对模拟氮沉降的响应。结果表明,氮沉降降低了人工林和天然林不同土层深度有机碳含量,有机碳含量下降幅度随氮沉降量的增加而增大,且表层土壤（0~20 cm）下降幅度大于深层土壤（20~40 cm,40~60 cm）。天然林表层土壤有机碳下降幅度大于人工林。氮沉降显著增加了人工林表层土壤全氮含量（P〈0.05）,但对天然林表层土壤全氮含量无显著影响（P〉0.05）。Through a long-term in situ simulated nitrogen（ N） deposition experiment,we explored the response and mechanism of soil organic carbon（ SOC） and total N content（ TN） to exogenous N addition in warmtemperate Chinese pine（ Pinus tabuliformis） forests. The levels of simulated N deposition were set as control（ 0 kg /（ ha·a）,N0）,low N（ 50 kg /（ ha·a）,N1）,medium N（ 100 kg /（ ha·a）,N2）,and high N（ 150 kg /（ ha·a）,N3）. Soil core method was used to investigate the responses of SOC and TN at different soil depths to simulated N deposition in the plantation and natural forests of P. tabuliformis. The results showed that SOC was reduced at different soil depths due to N deposition in both plantation and natural forests and the reduction of SOC was increased with N levels. Moreover,the SOC at surface layer（ 0-20 cm） declined more than that at deep layers（ 20-40 cm,40-60 cm）. Additionally,the SOC at surface layer in the natural forest declined more than that in the plantation. N deposition significantly increased soil TN at surface layer in the plantation（ P 〈0. 05）,however,the TN at surface layer in the natural forest was not significantly affected by simulated N deposition.

关 键 词：氮沉降 土壤有机碳 全氮 人工林 天然林 油松 

分 类 号：S718.554.2[农业科学—林学] S791.245