Abstract: The trend of the change in dependence of agricultural growth on resources and the interaction between agricultural development and environment change have attracted more and more attention from researchers the world over. Based on the theory of decoupling, data of a county as a whole during the two time spans from 2000 to 2005 and from 2005 to 2010, were analyzed to determine decoupling relationship between agricultural carbon emission and economic development in the Huang-Huai-Hai Plain, to reveal trends of the spatio-temporal variation of the decoupling development of the two and characteristics of its transfer and to explore inner mechanisms for decoupling. Results show that the type of decoupling has changed significantly in quantitative structure and spatial pattern, and the agricultural industry in the Huang-huai-hai Plain is right in the process of evolving from resource-dependence to technology-dependence. During the period of 2000 - 2005, agriculture carbon emissions and economic development was dominated with strong recoupling and expansive recoupling, and decoupling was rather dispersive in spatial pattern. However, the period of 2005 -2010 was dominated with strong decoupling and weak decoupling, and the decoupling zone displayed a trend of spatial agglomeration. If the affecting factors of carbon emission coefficient brought about by technological advancement are taken into account, the trend of decoupling would be more significant. The cause of forming this spatial pattern is the complicated relationship between economic development and environment. Factors, like economic development, technical advancement, institutional  innovation, etc. acted jointly on agricultural production and operation organizations through interactive mechanism. Transformation of decoupling types went like skipping, predominantly from strong recoupling and expansive recoupling to strong decoupling and weak decoupling, and moreover, the state of decoupling was unstable and it was very hard to keep on decoupling. The state of decoupling was subjected to the synergism of factors like economic effect, technical effect and policy effect. The dual character of the coaction of the three factors was the major cause of being hard to sustain decoupling.

Key words: agricultural carbon emissions, economic development, decoupling, temporal-spatial characteristics, Huang-Huai-Hai Plain