Abstract: Based on the classification of paddy wetlands in Youxian County of Hunan Province, theirspatial pattern and function are analysed, and their comprehensive benefit is assessed by AHP method. The results show that paddy wetlands can divided into submerged, percogenic, puddled and gley ones, and their dominances are respectively 4.17,26.4,12.32 and 31.25. The ratio of energy output and input is 4.68, and those of N, P and K output and input are respectively 0.59, 1.59 and 1.23. The comprehensive benefit is 0.66.

Key words: Paddy field, Wetland, Landscape ecosystem, Hilly region, precipitation regime, soil water content, transpiration, sap flow, semi-aridarea