Impacts of Climate and Nutrients on Carbon Sequestration Rate by Wetlands: A Meta-analysis

Global numerous wetlands are the most productive ecosystem and have high carbon sequestration potential to mitigate increasing CO(2)in the atmosphere. However, few are available on estimating average carbon sequestration rates by global wetlands (Carbon(sq)) at century timescale. In this article, Carbon(sq)data of 473 wetland soil/sediment cores from the literatures were collected in detail by the meta-analysis method. These cores were no more than 300 years old and spanned a latitudinal range from 33.6 degrees S to 69.7 degrees N. Globally, the average Carbon(sq)was 185.2 g/(m(2)center dot yr) regardless of wetland types. Carbon(sq)varied remarkably between wetland types and ranked as an order of salt marsh (247.7 g/(m(2)center dot yr)) > mangrove (229.8 g/(m(2)center dot yr)) > freshwater marsh (196.7 g/(m(2)center dot yr)) > peatland (76.9 g/(m(2)center dot yr)). Carbon(sq)was positively related to mean annual temperature (AMT) and annual precipitation (Pre). Nitrogen was the most common and primary factor controlling Carbon(sq)regardless of wetland types.