Temporal and spatial variability and controls of soil respiration in a temperate steppe in northern China
Temporal and spatial variability and controls of soil respiration in a temperate steppe in northern China
复制标题
中国北方温带草原土壤呼吸的时空变化及其控制
DOI：
10.1029/2009gb003538
复制
发表时间：
2010-05-20
影响因子：
5.2
通讯作者：
Li, Linghao
中科院分区：
文献类型：
--
作者：
Chen, Quansheng;Wang, Qibing;Li, Linghao
以内蒙古温带草原为研究对象，以土壤呼吸和环境变量为指标，探讨了沿沿着东西向样带的8个植物群落土壤呼吸的时空变异及其控制。结果表明，土壤呼吸具有显著的时间变异性（变异系数CV = 58.6 +/-1.54%，n = 14）和空间变异性（CV = 32.6 +/-2.65%，n = 8）。土壤温度和水分比植物生长更重要的控制在所有8个草原群落的场地内土壤呼吸的季节格局。土壤呼吸速率的空间差异主要是由土壤水分和净初级生产力（NPP）的差异引起的，而土壤温度对土壤呼吸的空间格局的调节作用较小。土壤呼吸与土壤碳、氮、粘粒含量等土壤性状之间存在显著的正相关关系。土壤呼吸与土壤容重、砂粒含量呈负相关。这些结果表明，非生物和生物因子在调节土壤呼吸的相对重要性在时间和空间上是不同的。从本研究得出的结论提供了有价值的信息，开发未来的土壤呼吸模型驱动的现场气候和土壤变量，适用于大规模的草地生态系统土壤呼吸的估计。
In this study, soil respiration and environmental variables were examined to explore the temporal and spatial variability and controls of soil respiration in eight plant communities along an east-west transect in a temperate steppe of Inner Mongolia, China. Our results show that there was substantial temporal (coefficient of variation (CV) = 58.6 +/- 1.54%, n = 14) and spatial variability (CV = 32.6 +/- 2.65%, n = 8) in soil respiration. Soil temperature and moisture were more important than plant growth in controlling the seasonal patterns of within-site soil respiration in all the eight steppe communities. Spatial differences in soil respiration rate could be mainly attributed to the differences in soil moisture and net primary productivity (NPP) among the study sites, whereas soil temperature played a minor role in regulating the spatial pattern of soil respiration. Significantly, positive site-to-site correlations were found between soil respiration and site soil traits such as soil C, N, and clay contents. In contrast, soil respiration was negatively correlated with soil bulk density and sand content. These findings indicate that the relative importance of abiotic and biotic factors in regulating soil respiration differs temporally from spatially. The conclusions drawn from the present study provide valuable information for developing future models of soil respiration driven by site climatic and soil variables, applicable for large-scale estimates of soil respiration in grassland ecosystems.