Carbon absorption and emission in the farmland ecosystem of Dezhou City in Shandong Provincewere estimated and their changes were analyzed based on the statistical data of crop yield

cultivated land areaand agricultural input from 2001to 2010.The total carbon absorption in the farmland ecosystem showed anincreasing trend during 2001-2010and the increasing trend was obvious after 2004.The carbon absorptionof wheat and corn

as the main grain crops

was significantly higher than other crops

and the carbon absorption of cotton

as the main cash crop

was not high.The carbon emission presented the trend from increasingto decreasing due to eco-efficient and high-quality crop development.Different counties had different carbonemissions because of different agricultural development directions and characteristics.The carbon emission ofchemical fertilizer contributes a higher percentage in three ways of carbon emissions

which showed a decreasing trend.The carbon absorption was far higher than the carbon emission in Dezhou City from 2001to2010.Farmland ecosystem of Dezhou City had an evident carbon sink function.