田间条件下黑垆土基础呼吸的季节和年际变化特征  

Seasonal and annual variation characteristic in basal soil respiration of black loam under the condition of farmland field

作　　者：张彦军[1] 郭胜利[1,2,3] 刘庆芳[3] 南雅芳[3] 郭慧敏[2] 李俊超[3] 

机构地区：[1]西北农林科技大学水土保持研究所,杨凌712100 [2]中国科学院水利部水土保持研究所,杨凌712100 [3]西北农林科技大学资源与环境学院,杨凌712100

出　　处：《生态学报》2013年第22期7270-7276,共7页Acta Ecologica Sinica

基　　金：2012年公益性行业(农业)科研专项经费资助项目(201203039);国家自然科学基金资助项目(41071338)

摘　　要：明确土壤基础呼吸的季节和年际变化及其影响因素,对了解土壤有机碳的变化机理具有重要的意义。在长武农田生态系统国家野外科学观测研究站,依托其长期(始于1984年)的裸地处理,于2009—2011年,利用Li-8100系统(Li-COR,Lincoln,NE,USA)监测了土壤呼吸、土壤水分和土壤温度,研究田间条件下土壤基础呼吸的年际和季节间变化及其与环境变量之间的关系。裸地土壤呼吸具有显著地季节和年际变异特性。2009年土壤呼吸速率波动于0.62—1.83μmol·m-2·s-1,平均为1.16μmol·m-2·s-1;2010年土壤呼吸的变化范围为0.30—1.46μmol·m-2·s-1,均值为0.92μmol·m-2·s-1;2011年则为0.06—1.68μmol·m-2·s-1和0.88μmol·m-2·s-1。2009到2011的3a期间裸地土壤呼吸的年累积量依次为282、234和230 g C/m2。裸地土壤呼吸与土壤温度呈显著指数关系,而与土壤水分呈显著一元二次方程关系。土壤温度和土壤水分共同控制土壤呼吸的变化。试验期间,土壤呼吸累积量与试验期间降水总量相反,但与年均气温无关。在裸地处理上,因土壤呼吸年流失有机碳达到2.5Mg C/hm2。Basal soil respiration is an important factor to influence soil organic carbon dynamics in the terrestrial ecosystem. Soil respirations were measured with the automated CO2 flux system （Li-8100,） in a long-term bare soil in the Changwu State Key Agro-Ecosystem Experimental Station （35° 12′ N, 107° 40′ E）, Shaanxi, China from March 2009 to November 2011. Soil temperature and soil moisture at the 5-era depth was measured using a Li-COR thermocouple and oven drying method, respectively. Significant variations in seasonal and annual soil respiration were observed in the experimental period of three years. Soil respiration averaged at 1.16 μmol. m-2. s-1, 0.92 μmol. m-2. s-1 and 0.88 μmol-m-2. s-1 in 2009, 2110 and 2011, respectively. The cumulative soil respiration in 2009, 2010, and 2011 soil were 282 g C/m2, 234 g CO2/C mE and 230 g C/mE, respectively. The soil respiration was significantly related with seasonal soil temperature or soil moisture. A bivariate model more accurately soil respiration in the bare soil ecosystem than a univariate model with only soil temperature or soil moisture as the driver. During the experimental period of three years, the accumulation of soil respiration in bare soil was negative correlation with annual precipitation, whereas there was no relationship between soil respirationand annual air temperature. In the bare soil, the annual loss of carbon was estimated at 2.5 Mg/hm2 according to soil respiration.

关 键 词：土壤呼吸 土壤水分 土壤温度 裸地 

分 类 号：S154[农业科学—土壤学]