增温对秦岭温带森林土壤N_(2)O通量的影响  

Effects of Warming on Soil N_(2)O Flux in Qingling Temperate Forest

作　　者：王小鸽[1] 彭长辉[2] 薛巍[2] 王辉[2] 李卫忠[2] Wang Xiaoge;Peng Changhui;Xue Wei;Wang Hui;Li Weizhong(Yangling Vocational&Technical College,Yangling Shaanxi 712100,China;College of Forestry,Northwest A&F University,Yangling Shaanxi 712100,China)

机构地区：[1]杨凌职业技术学院,陕西杨凌712100 [2]西北农林科技大学林学院,陕西杨凌712100

出　　处：《西南林业大学学报（自然科学）》2021年第4期35-41,共7页Journal of Southwest Forestry University：Natural Sciences

基　　金：国家重点研究发展计划(十三五规划-2016YFC0500203)资助;陕西省林业重点项目(SHLY-2018-02)资助。

摘　　要：为探讨气候变暖对温带森林土壤N_(2)O通量的影响,在秦岭火地塘林区锐齿栎林内利用开顶式增温装置对土壤进行2 a的增温模拟试验,分析增温条件下土壤N_(2)O通量的变化规律和土壤特性对N_(2)O通量的影响。结果表明:增温处理使锐齿栎林土壤N_(2)O通量增加了13.9%,年排放量(1.88±0.57)kg/(hm^(2)·a),其中显著增加了春季和夏季土壤N_(2)O通量。增温处理对土壤碳氮含量影响显著,与对照相比,土壤硝态氮含量平均增加8.4%,土壤有机碳和全氮含量分别下降了30.1%、34.9%,C/N提高了7.5%。土壤N_(2)O通量与土壤温度、含水量、硝态氮含量,呈显著的正相关(P<0.05),与土壤有机碳含量呈显著负相关(P<0.05)。土壤温度和硝态氮含量可以解释土壤N_(2)O通量变异的70%以上,土壤含水量可以解释变异的39.5%。因此,土壤温度和硝态氮含量是影响土壤N_(2)O通量的关键因子,未来气候变暖会增加秦岭锐齿栎林土壤N_(2)O的排放。In order to investigate the effect of global warming on soil N_(2)O flux from temperate forest,we conducted warming experiment using open top chambers(OTC)for 2 years in the Quercus aliena var.acutiserrata forest in Huoditang forest Station,Qinling Mountains.In this study,we explored the emission pattern of N_(2)O and the effect of edaphic factors after soil warming.The results showed that the annual N_(2)O flux increased by 13.9%with an average of(1.88±0.57)kg/(hm2·a)after soil warming,and N_(2)O flux was significantly increased in spring and summer.Soil warming significantly increased soil NO_(3)^(−)−N content by 8.4%and decreased soil organic car-bon and total N contents by 30.1%and 34.9%,respectively,and consequently increased C/N ration by 7.5%.The N_(2)O flux had a significantly positive correlation with soil temperature,water filled pore space and NO_(3)^(−)−N con-tent(P<0.05).There was a significantly negative correlation between soil SOC content and N_(2)O flux(P<0.05).The soil temperature,NO_(3)^(−)−N content and WFPS accounted for 70%and 39.5%of the variation in N_(2)O flux,respect-ively.Therefore,soil temperature and NO_(3)^(−)−N content were the key factors affecting N_(2)O emission.The projec-ted climate warming would increase the N_(2)O flux in in the Q.aliena var.acutiserrata forest of Qinling Moun-tains.

关 键 词：增温 森林生态系统 N_(2)O通量 土壤有效氮 

分 类 号：S714[农业科学—林学]