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土壤异养呼吸主要指土壤中微生物分解有机质释放CO2的过程,是陆地生态系统中土壤碳的主要净输出途径,土壤异养呼吸与净初级生产力的差值是决定生态系统碳源/汇的关键。本文介绍了土壤异养呼吸的测定方法———室内培养的去根土壤样品培养和原状土柱培养,以及野外原位测定的根排除法、环割法和同位素法等操作方法的优缺点以及适用范围。在土壤异养呼吸的研究方面,土壤异养呼吸温度敏感性(Q10)是碳循环研究的重要方面之一,温度、水分以及土壤呼吸底物是影响Q10的主要因子,一般情况下,随着温度的升高,Q10下降;土壤含水量过低或过高时,Q10降低;土壤有机碳的有效性影响着土壤异养呼吸对温度变化的响应程度,当有效性降低时Q10下降,不同周转时间的有机碳的温度敏感性也不相同,活性有机碳的温度敏感性较惰性有机碳的温度敏感性低。
Soil heterotrophic respiration mainly refers to the process by which microorganisms in the soil decompose organic matter to release CO2 and is the main net output of soil carbon in terrestrial ecosystems. The difference between heterotrophic respiration and net primary productivity is the key factor that determines ecosystem carbon source / sink . In this paper, the methods of determination of heterotrophic respiration in soils, ie, cultivation of soil samples for root exudation in indoor culture and cultivation of undisturbed soil columns, as well as the advantages and disadvantages of the root exclusion method, ring cutting method and isotope method, The scope of application. Soil heterotrophic respiration temperature sensitivity (Q10) is one of the important aspects of carbon cycle research in the study of soil heterotrophic respiration. Temperature, moisture and soil respiration substrate are the main factors affecting Q10. Under normal circumstances, Q10 decreased when the soil moisture was too low or too high, and the Q10 decreased when soil moisture was too low or too high. The availability of soil organic carbon affected the response of soil heterotrophic respiration to temperature changes. When the effectiveness decreased, Q10 decreased, The temporal carbon sensitivities are also different, and the active organic carbon is less sensitive to temperature than the inert organic carbon.