Abstract:

The Chang-Zhu-Tan urban agglomeration is one of the most important regions with well-developed socio-economy in the middle reaches of the Yangtze River. The study on carbon effect arising from transformation of land use types is of vital significance to carbon emission management and low carbon space planning in urban areas. Based on the land use data, vegetation type maps and soil type maps of 1990, 1995, 2000, 2005 and 2010 of the Chang-Zhu-Tan urban agglomeration, carbon effects arising from changes in land use/cover over the 20 years in the region were analyzed from the aspects of land use structure, its transformation direction, and consequent variation of carbon emission intensity and spatial distribution of carbon sequestration. Results show that: (1) in the period from 1990 to 2010, the changes in land use in the Chang-Zhu-Tan urban agglomeration were characterized mainly by transformations of cultivated land into wood land and vice versa, and of cultivated land and wood land into construction land; (2) the changes in carbon effect demonstrated a reversed "U-shape" trend, a weakening overall carbon sequestration capacity and distinct spatial differentiation of carbon effect. Compared with other areas, the five areas of the Urban Agglomeration, i.e. Changsha City, Zhuzhou City, Xiangtan City, Wangcheng County and Changsha County, witnessed remarkable changes in carbon effect and carbon sequestration capacity as a result of changes in land use, but the changes varied sharply from area to area, which is thought to be directly related to regional population density and unbalanced development of regional economy; and (3) it is advisable to control and use-triggered carbon emission through limiting alienation of forest land and grassland, optimizing land use structure and economic layout, and preventing fragmentation of habitat and degradation of ecosystem.

Key words: Chang-Zhu-Tan urban agglomeration, land use/cover, carbon effect