We reviewed the measurement methods, measurement scale, modeling method, and application of soil respiration in terrestrial ecosystems, in order to provide relevent information about this important carbon cycle process. Soil respiration is a process that release CO2 from the soil to atmosphere. Soil respiration has important impacts on the carbon balance in ecosystem. Methods for measuring soil respiration can be classified into the three types which are alkali absorption method, closed chamber-gas chromatograph method and infra-red gas analyzer method. Scales for measuring soil respiration can be classified into four types which are daily change measurements, seasonal change measurements, interannual change measurements and spatial change measurements. Given enough in situ measurement data available, the temporal and spatial variability in soil respiration can be simulated by semi-empirical models, which use precipitation, air temperature, soil property, vegetation characteristics, nitrogen deposition, latitude and longitude as input variables. The semi-empirical models which are the main methods for estimating global soil respiration have given the reasonable scales 88.0~98.0 Pg·a-1(by C). On the other hand, although most terrestrial biogeochemical models include the module simulating the dynamics of soil organic carbon, they do not include the module for simulating soil respiration. The study of soil respiration has important application values. Firstly, soil respiration is the indicator of soil fertility. Secondly, other terrestrial carbon fluxes can be estimated, as soil respiration is correlated to other carbon fluxes. Thirdly, the response of soil respiration to the global change is an important aspect of the ecological response to global change. Future investigations should focus on the simultaneous measurements of soil respiration and climate, soil, and vegetation factors, which may improve the accuracy of modeling the temporal and spatial variability in soil respiration. The long-termin situ measurements of soil respiration in typical ecosystems are also needed, which may be useful to analyze the response of soil carbon pool to environmental factors.%主要对陆地生态系统土壤呼吸的观测方法、观测尺度、模拟方法、应用价值进行评述,以期为更深入地研究土壤呼吸这一重要的碳循环过程提供一些参考依据.土壤呼吸是土壤向大气释放CO2的过程,其对生态系统碳平衡具有重要影响.土壤呼吸的观测方法主要包括碱液吸收法、密闭箱–气相色谱法、红外气体分析法.土壤呼吸的观测尺度主要包括日变化、生长季变化、年际间变异、空间变异.在获得充足实测数据的基础上,半经验模型可有效地模拟土壤呼吸的时空变异.这些半经验模型以降水、气温、土壤性质、植被特征、氮沉降、经纬度作为输入变量,是当前估算全球土壤呼吸的主流模型,其估算的全球土壤呼吸量的合理范围为88.0~98.0 Pg·a-1(以C计).土壤呼吸研究具有重要的应用价值:(1)土壤呼吸是土壤肥力状况的表征指标;(2)土壤呼吸与其他碳通量指标具有相关性,利用模拟的土壤呼吸量值可估算其他碳通量;(3)土壤呼吸对全球变化的响应规律是生态系统对全球变化的响应规律的重要表现方面.今后的研究应关注土壤呼吸与气候、土壤、植被因子的同步观测,这将大大提高土壤呼吸时空变异模拟的准确性,还应对一些典型生态系统的土壤呼吸进行长期定位观测,这有助于分析土壤碳库对环境因子变化的响应规律.
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