Resnonses of forest soil methane uptake to global change
Forest soils are the main sink of atmospheric methane(CH4)in the terrestrial ecosystems.Global chan-ges,such as increasing atmospheric CO2 concentration,warming,changing rainfall regime,and increasing nitrogen(N)deposition,affected soil CH4 uptake by altering soil physicochemical properties,plant growth,and soil micro-organisms.In this study,we conducted a meta-analysis of the impacts of global changes on CH4 uptake in forest soils.Based on 195 sets of data collected from 155 papers,we found that the rate of CH4 uptake by forests decreased significantly under elevated CO2 and N deposition,but increased under drought.There were no significant differences in CH4 uptake rates at the annual scale in tropical,temperate,and boreal forests.Global warming did not affect CH4 uptake rates in forest soils.Moreover,the results of seasonal and drought experiments on forest soil CH4 uptake demonstrated that soil moisture was negatively correlated with CH4 uptake.The linear model of CH4 uptake in soil water balance fitted in this study did not reflect the negative correlation between soil water surplus and soil CH4 uptake.These results indicate that soil water balance model requires more empirical data when it is applied at the global scale.Our results shed light on future experiments related to the impacts of global change on CH4 uptake in forest soils.
climate changemeta-analysisCO2 concentrationsoil water
万方数据
维普
