%0 Journal Article
%T Carbon Budget Dynamics over a Rain-Fed Maize Agricultural Ecosystem in Northeast China and Its Regulation
%A Rongping Li
%A Guangsheng Zhou
%A Li Zhou
%A Yang Yang
%J Open Journal of Ecology
%P 377-391
%@ 2162-1993
%D 2017
%I Scientific Research Publishing
%R 10.4236/oje.2017.76027
%X Based on the eddy-covariance observation data over rain-fed maize agricultural ecosystem during 2005-2011, the dynamics of net ecosystem CO2 exchange (NEE) and its control mechanism were analyzed in the present study. We found that the average carbon budget of non-growing season, growing season and annual were 153.16 - 202.03 g C/m2, −689.36 - −488.17 g C/m2, and −316.96 - −487.33 g C/m2, respectively. Maize carbon content of grain yield was −226.6 - −339.94 g C/m2, accounting for 55.4% of carbon budget in the growing season. From sowing to seven-leaf stage, the carbon budget of this ecosystem was characterized by carbon release, with the rate of 0.028 ± 0.0056 mg CO2 m−2⋅s−1. From seven-leaf to mature stage, the carbon budget was characterized by carbon absorption, with the rate of −0.256 ± 0.0693 mg CO2 m−2