关键词: 土壤有机质, 碳同位素, 碳循环, 亚热带, 鼎湖山

Abstract: By using Landsat TM images and socio-economical data, the dynamics of urban sprawl in Suzhou City from 1984 to 2003 was investigated, and analyzed from multi-disciplinary viewpoint. The results showed that with the rapid urbanization and industrialization, an overwhelming consumption of urbanused land from non-agricultural land was happening everywhere in the study area. In the past 20 years (1984 to 2003), the urban-used land had grown about 2.9 times, from 10 200 hm² in 1984 to 29 200 hm² in 2003. Temporally, urban-used land had a marked increasing intensity, while spatially, it expressed as the sequence of urban > town> village. The land consumption per capita in urban area (including urban and town) was lesser than that in village, indicating that in the Yangtze Delta, the most urbanized area in China, and at least in Suzhou or in other cities with the similar economic patterns to Suzhou in the Southeast China, further urbanization would help to weaken the conflict between urbanization and food security intrigued by the decrease of farmland.

Key words: Soil organic matter, ¹⁴C, Carbon cycling, Subtropical zone, Dinghushan Biosphere Reserve