摘要
毛竹(Phyllostachys edulis)是中国南方重要的森林资源,在区域碳平衡中扮演重要的作用。研究毛竹林土壤呼吸特征及影响因子有助于了解其土壤CO2释放过程的关键驱动因子,为进一步揭示毛竹林土壤碳循环特点提供科学依据。以浙江省西天目山自然保护区毛竹林为研究对象,利用LI-Cor8100开路式土壤碳通量测量系统测定(2007年5、8、11月,2008年1、3月)土壤呼吸速率及环境因子,同时取0—20 cm土层土样测定土壤酶活性,结果表明:(1)毛竹林土壤呼吸具有典型的日动态和季节变化模式,日动态变化较为平缓,土壤呼吸的季节变化较为显著(P<0.05),最大值(5.99μmol.m-2.s-1)出现在2007年8月,最小值(1.08μmol.m-2.s-1)出现在2008年1月。(2)回归方程表明,土壤呼吸与土壤5 cm温度呈极显著的指数相关关系(P<0.001),与土壤体积含水量相关性较弱(P>0.05),与近地面大气温度和CO2浓度分别呈极显著的指数相关关系(P<0.001)和显著的线性相关关系(P<0.05)。(3)相关分析表明,土壤尿酶、蔗糖酶、纤维素酶活性与土壤呼吸均呈正相关,其中纤维素酶活性达到显著水平。综合分析表明毛竹林土壤温度是调控土壤呼吸季节变化的主要驱动因子,近地面大气环境及土壤酶活性的变化也对其产生不容忽视的影响。
The phyllostachys edulis are the most important composition of forest resources in the south of China.In order to quantify soil respiration dynamics and its regulating factors,we conducted a set of relevant experiments in phyllostachys edulis forest in west Tianmu Mountain,Zhejiang province.Soil respiration rate and relevant factors were measured by Li-cor8100 from May 2007 to March 2008,then we investigated soil enzyme activities above 20cm surface.Results were displayed as follows：（1） Soil respiration of phyllostachys edulis forest emerged typical diurnal and seasonal dynamic patterns.The diurnal variation was gentle,the mean soil respiration showed significant difference among seasons（P 0.05）;the maximum（5.99μmol·m-2·s-1） appeared in August 2007,the minimum（1.08μmol·m-2·s-1） appeared in January 2008.（2） Regression equation analysis showed that the relationship between soil respiration and soil temperature of 5cm depth can be described as an exponential equation,and it was very significant（P 0.001）.The relationship between soil respiration and soil volumetric water content can be described as linear equation,but it was not significant（P 0.05）.The relationship between soil respiration and near-surface atmospheric temperature were described as an exponential equation,it was a close relation（P 0.001）.The relationship between soil respiration and CO2 concentration were described as a liner equation,it was a significant correlation（P 0.05）.（3）Correlation analysis showed that urease,sucrase and cellulase activities and soil respiration were positively correlated,but only the activity of cellulase achieved a significant level.All of these results suggest that soil temperature is a dominant factor to impact soil respiration,yet the effect of near-surface atmospheric conditions and soil enzymes could not be ignored.
出处
《生态学报》
CAS
CSCD
北大核心
2010年第17期4590-4597,共8页
Acta Ecologica Sinica
基金
科技部973项目(2005CB422207&2005CB422208)
科技部数据共享平台建设项目(2005DKA32306和2006DKA32308)
科技部国际合作项目(20073819)
科技部重大科技基础项目(2007FY110300)
国家自然科学基金项目(40671132)
浙江省科技厅重大项目(2006C12060和2008C13G2100010)资助
关键词
毛竹
土壤呼吸
环境因子
脲酶
蔗糖酶
纤维素酶
Phyllostachys edulis
soil respiration
environmental factors
urease
sucrase
cellulase
作者简介
通讯作者Correspondingauthor．E-mail：Hongjiang．china@gmail．com.
