大气CO2浓度升高对土壤碳库的影响

Effects of elevated atmospheric CO_2 concentration on soil carbon

土壤碳库是输入、输出土壤碳量的平衡:大气CO2浓度升高有可能通过生态系统中的各种生理过程来增加输入土壤的碳量,输入土壤碳量的增加使土壤成为一个潜在的碳汇,有可能缓解大气CO2浓度的升高;但另一方面输入土壤碳量的增加,为微生物的生长提供了能量,从而提高了微生物的活性,因此土壤呼吸增强,土壤碳输出增加。本文综述了大气CO2浓度升高对土壤碳输入、输出的影响以及目前研究中存在的争论,并提出有待进一步研究的领域和方向。

Soil carbon is the balance between carbon input into and loss from the soil. CO2 enrichment may increase new carbon input into the soil,making it a potential carbon pool,and therefore mitigate increasing of the atmospheric C02 concentration. However,increased carbon input into the soil may lead to more available substrate for microorganisms,increasing microorganismic activity,thereby enhancing soil respiration,hence more soil carbon loss. In this paper,we advance the effect of elevated CO2 on soil carbon input and output,review scholarly debates on the displine and recommend further studies.