模拟氮沉降对华西雨屏区慈竹林土壤呼吸的影响  

Effects of simulated nitrogen deposition on soil respiration in a Neosinocalamus affinis plantation in Rainy Area of West China

作　　者：李仁洪[1,2] 涂利华[1] 胡庭兴[1] 张健[1] 鲁洋[2] 刘文婷[1] 雒守华[1] 向元彬[1] 

机构地区：[1]四川农业大学林学院四川省林业生态工程省级重点实验室,四川雅安625014 [2]四川省林业调查规划院,成都610081

出　　处：《应用生态学报》2010年第7期1649-1655,共7页Chinese Journal of Applied Ecology

基　　金：国家"十一五"科技支撑计划重大项目(2006BA01A11-03);四川省重点学科建设项目(SZD0419);四川农业大学"211"工程建设科技支撑计划项目资助

摘　　要：2007年12月至2008年11月,在华西雨屏区采用0(对照)、50、150、300kg.hm-2.a-1施氮处理和红外CO2分析法,研究了模拟N沉降对慈竹林土壤呼吸特征的影响.结果表明:慈竹林土壤呼吸速率年内季节变化呈明显的单峰型曲线,7月末最高,为(3.36±0.20)μmol.m-2.s-1,2月末最低,为(0.33±0.07)μmol.m-2.s-1.土壤呼吸速率与土壤温度之间呈极显著指数相关(P<0.001),10cm深的土壤温度解释了土壤呼吸速率季节变化的91.6%;而土壤含水量与土壤呼吸之间相关性不显著(R2=0.0758).2008年6—11月根呼吸对土壤总呼吸的贡献率在46%～59%.50、150和300kg.hm-2.a-1施氮处理的年CO2释放量分别比对照低23.6%、46.7%和50.5%.0、50、150和300kg.hm-2.a-1施氮处理的土壤呼吸速率Q10值分别为3.72、3.51、2.95和2.71.From December 2007 to November 2008,an in situ experiment was conducted to study the effects of simulated nitrogen deposition on the soil respiration in a Neosinocalamus affinis plantation in Rainy Area of West China.Four treatments were installed,i.e.,0 （CK）,50,150,and 300 kg N·hm-2·a-1,and soil respiration rate was measured by infrared gas analyzer.In the test plantation,soil respiration rate had a distinct seasonal fluctuation,with the highest （3.36±0.20 μmol·m-2·s-1） by the end of July and the lowest by the end of February （0.33±0.07 μmol·m-2·s-1）.There was a significant exponential relationship （P0.001） between soil respiration rate and soil temperature,and the temperature at 10 cm soil depth explained 91.6% of the seasonal change of soil respiration.However,less relationship was observed between soil respiration rate and soil moisture content （R2=0.0758）.From June to November 2008,the contribution of root respiration to total soil respiration ranged from 46% to 59%.The annual release amount of CO_2 in treatments 50,150,and 300 kg·hm-2·a-1 was 23.6%,46.7%,and 50.5% lower than that in CK （2.17×104 kg ·hm-2）,and the Q_10 value of soil respiration rate in treatments 0,50,150,and 300 kg·hm-2·a-1 was 3.72,3.51,2.95,and 2.71,respectively.

关 键 词：氮沉降 土壤呼吸 慈竹林 华西雨屏区 

分 类 号：S714[农业科学—林学]