Flooding influences on the C, N and P stoichiometry in terrestrial ecosystems: A meta-analysis

Extreme climate events such as flooding have profound impacts on the nutrient stoichiometry and function of terrestrial ecosystems. This study aimed to investigate the influencing mechanisms of flooding on C:N:P stoichiometry in different terrestrial ecosystems, which mainly focused on abiotic factors and their linkages with biotic factors. A global meta-analysis of 69 published studies (885 paired observations) was conducted to examine the effects of flooding on the C:N:P stoichiometry of plants, soil and microorganisms in different terrestrial ecosystems. The collected data included broad variations in climate parameters and flooding durations. Flooding was found to significantly elevat the C and N contents of the whole ecosystem. The responses of overall (across plant-soil-microorganism) C, N and P contents to flooding were pronounced among different ecosystem types or components. Flooding markedly increased the ratios of overall C:N, C:P and N:P ratios by 9.7%, 20.1% and 7.4%, respectively. Flooding with a short duration elevated the overall C:P ratio more than C:N and N:P ratios. Flooding regulated the ecosystem components of C and N, with both elements were also being affected by duration times and climate parameters to some extent. These results provide new insights into understanding the impacts of extreme climate events on ecosystem nutrient turnover under the circumstance of global climate change.