关键词: 生态效益, 围湖造田, 经济效益, 农业生态

Abstract: In the early 1970's guided by the policy of "Grain must be taken as the key link in agriculture", people in Hubei and some other provinces in China started a "land reclaimed from lake" upsurge, which however incurred some knotty problems in the reclaimed areas. Ecological and economic cost-benefit analyses are made in this paper based on the data obtained from the reclaimed lake regions. It is concluded that land-reclamation should be regarded as a kind of disadvantageous action because of its adverse impacts on agricultural ecology, fishery, navigation and the climate in the reclaimed areas, which has been shown in recent years despite its limited benefits in grain production and in the elimination of oncomelania, the host of blood fluke.This paper points out that only by exploiting and utilizing lake resources properly can lakes be well manayed and protected, and can those renewable and valuable resources be constantly available for human beings.

Key words: ecological cost-benefit, land-reclamation from lake, economic cost-be- nefit, agricultural ecology