Abstract: Based on the viewponits of systemology and the principles of agro-ecological engineering,the designing of home garden ecolomic system with methane generating as a tie in Nanxian county,Hunan province is differentiated and analysed systematically. Five kinds of developing types and basic ways of designing are introduced,and their structures,functions and efficiencies are analysed and evaluated quantitatively. The results show that in developing home garden economic system,methane generating can play a role of tie and multiple functions,make various vital factors of production and life of household ecosystem interdependent and inter-promotive,and achieve more comprehensive efficiency. The establishment of home garden economic system with methane generating as a tie is also discussed.

Key words: Salvia miltiorrhiza, seedling index, correlation , analysis, correlation degree analysis, simulation model.