Abstract:

The carbon emissions from agricultural ecosystem of the Wan Jiang City Belt from 1991 to 2010 was calculated based on seven main kinds of agricultural carbon sources including fertilizers,pesticides,agricultural films,agricultural irrigation,farmland tillage,agricultural machinery and the decomposition of roots after the harvest of the crops.The result showed that the carbon emissions from the farmland of the research area from 1991 to 2010 increased from 273 to 535 million ton with an average annual growth rate of 1035%,meanwhile the carbon emissions accounted for 443% of the total amount of Anhui province in 2010.The carbon emissions from the farmland per capital and the density of carbon emissions had an average growth rate of 26% and 584% respectively during 19912010,while the carbon emission intensity decreased 3769 t/（108 Yuan·a）. The decomposition of the residual roots of the crops after harvest which accounted for 5987% was the main composition of the carbon emissions from farmland in the research area,simultaneously carbon emissions from fertilizers increased the most with an average growth rate of 1618%. Among all the cities of the research area, the maximum of carbon emissions from farmland was in Lu’an and the average growth was 298×104 t/a, followed by Anqing, and the minimum was in Tongling with the least growth of 900 t/a.The maximum of carbon emission intensity was in Lu’an,secondly in Chuzhou with the largest decrease of 64774 t/(108 Yuan·a),while the minimum was in Tongling with the least decrease of 19760 t/(108 Yuan·a).The maximum of carbon emissions from farmland per capital was in Chuzhou,but the minimum was in Tongling.The maximum of the increased amount per capital was in Lu’an which was 460 kg/a,while the minimum was in Hefei which was 039 kg/a.The maximum of the average growth rate of carbon emission density was 836% in Wuhu,while the minimum was 345% in Ma’anshan.Finally,some suggestions were put forward to reduce the carbon emissions from farmland according to the characters of the formation and dynamics of agricultural carbon sources in the research area