塔克拉玛干沙漠腹地冬季土壤呼吸及其驱动因子  

Environmental factors driving winter soil respiration in the hinterland of the Taklimakan Desert,China

作　　者：刘跃辉[1,2,3] 艾力·买买提依明 杨帆[2,3] 杨兴华[2,3] 何清[2,3] 

机构地区：[1]新疆大学,资源与环境科学学院,乌鲁木齐830046 [2]中国气象局乌鲁木齐沙漠气象研究所,乌鲁木齐830002 [3]塔克拉玛干沙漠大气环境观测试验站,塔中841000 [4]南京信息工程大学应用气象学院,南京210044

出　　处：《生态学报》2015年第20期6711-6719,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金(41175140);公益性行业(气象)科研专项(GYHY201306066)

摘　　要：利用Li-8150系统测定了塔克拉玛干沙漠腹地冬季(1月)土壤呼吸,分析了环境驱动因子对极端干旱区荒漠生态系统土壤呼吸的影响。结果表明:(1)冬季土壤呼吸日变化呈现出显著的单峰曲线,土壤呼吸速率最大值出现在12:00,为0.0684μmol CO2m-2s-1,凌晨04:00附近出现最小值,为-0.0473μmol CO2m-2s-1;(2)土壤呼吸速率与各层气温,0cm地表温度均存在着极其显著或显著的线性关系,且都具有正相关性;(3)土壤呼吸速率与5cm土壤湿度存在着较为明显的线性关系,该层湿度能够解释土壤呼吸的69.5%;(4)0cm地表温度对土壤呼吸贡献最大,其次是5cm土壤湿度;(5)以0cm地表温度、5cm土壤湿度为变量,通过多元回归分析表明:土壤温度-湿度构成的多变量模型能够解释大于86.9%的土壤呼吸变化情况;(6)研究时段内土壤呼吸速率的平均值是-1.45mg CO2m-2h-1。In order to analyze the environmental drivers of soil respiration in an extreme arid desert ecosystem,we measured diurnal variation in winter soil respiration at Tazhong,a hinterland of Taklimakan Desert in northwest China. Regression analysis was performed with SPSS 21. 0. We observed that：（ 1） Diurnal variation in winter soil respiration showed a single peak at 12： 00 noon（ local time）,after which soil respiration began to decrease,reaching a minimum value at around 4： 00 a. m.（ 2） Soil respiration and the air temperature at each height tested（ 0. 5 m,2 m） were significantly and positively correlated. Air temperature at 2 m was able to explain 67. 8% of the diurnal variation in soil respiration.（ 3） Soil temperature at 0 cm,modeled by linear equations,was able to explain 86. 3% of the diurnal variation in soil respiration,demonstrating that this process is more sensitive to temperature at 0 cm than at any other soil layer（ 10 cm,20 cm,40 cm）.（ 4） Soil respiration exhibited a positive linear correlation with soil moisture at a depth of 5 cm. When linear regression analysis was used to model the relationship between these variables,the fitted linear model explained 69. 5% ofthe diurnal variation in soil respiration,demonstrating that,in the extreme arid desert ecosystem,this shallow layer of moisture exerts a large effect on soil respiration.（ 5） The greatest contributors to soil respiration were soil temperature at a depth of 0 cm,followed by soil moisture at 5 cm.（ 6） Multiple regression analyses showed that a multi-variable model of temperature and soil moisture explains 86. 9% of the diurnal variation in soil respiration,which is not significantly better than a single-variable model.（ 7） For winter soil respiration,the daily average rate of CO2 absorption was- 1. 45 mg CO2m- 2h- 1.

关 键 词：塔克拉玛干沙漠 土壤呼吸 温度 土壤湿度 

分 类 号：S154[农业科学—土壤学]