Research On Agricultural Eco-efficiency In Xiangxi Area From The Perspective Of Emergy

Xiangxi Area is located in the west of Hunan Province,the economic development foundation is weak,and the overall level of social development is low.Because of its rich natural resources,agriculture and tourism are the most advantageous industries.Hunan Province,the precise poverty alleviation policy and"13th Five-Year development plan" has been clearly put forward that to rely on agriculture and ecological advantages to help implement the policy of poverty alleviation in Xiangxi Area,take advantage of the opportunity to build ecological and cultural belt in Western Hunan and construct Xiangxi mountain ecological agriculture area.Under the requirement of the construction of ecological civilization,the development of agriculture in Xiangxi Area must take the modern efficient ecological agriculture as the goal,utilize the resources efficiently and explore the path of sustainable development.Therefore,it is necessary to understand the present situation of the agricultural ecosystem in Xiangxi,and to evaluate the efficiency and sustainable development of Xiangxi agricultural ecosystem.In this paper,emergy analysis method is used to analyze the agricultural ecosystem of Xiangxi Aera,and the results and conclusions are as follows:① As for agricultural ecosystem in Xiangxi Area,its emergy investment is 3.59E+22sej,accounting for 40%of total emergy investment of agricultural ecosystem in Hunan Province and emergy yield of agricultural products is 1.56E+23sej,accounting for 30.7%of total emergy yield of Hunan province.②Emergy investment on environment and resources accounts for a great proportion in agricultural development in Xiangxi Area for 31.97%(Emergy Self-Sufficiency Ratio)with average level of Hunan Province of 29.25%.It shows that investment on environment and resources costs a lot for economic development of agricultural ecosystem in Xiangxi Area.③ Emergy investment on labor force and chemical fertilizer accounts for 60.62%of total emergy investment in agricultural ecosystem in Xiangxi Area with Hunan Province of 42.52%,while emergy investment on machinery,diesel,and organic fertilizer is relatively low.It means that the ecosystem is still at traditional stage with the extensive development pattern which is supported by a large amount of labor force and fertilizers.In contrast to Hunan Province,emergy investment ratio of Xiangxi Area is still on or below the medium level in Hunan Province.Therefore,agricultural ecosystem is still undeveloped for large investment on environment and resources but low utilization efficiency of agricultural ecosystem in Xiangxi Area.④Among products of agricultural ecosystem in Xiangxi Area,crop farming ranks No.1 followed by stocking breeding,while forestry and fishery account for less.As for crop farming,Chinese herbal medicine is in leading role while oil plants,grain,and fruit are still in advantageous position.As for stock breeding,pork is still in leading position with beef and poultry still in advantageous position.Emergy yield ratio is 6.41,which is much lower than Hunan Province of 8.05.Overall speaking,industry emergy return ratio is relatively low and industry competitiveness is rather low.⑤As for emergy yield of five regions in Xiangxi Area,Shaoyang is more advantageous in grain,beans,Chinese herbal medicine,pork,mutton,poultry,milk,tea-oil tree,and aquatic product.There is higher emergy yield of Huaihua in cotton,oil plants,sugarcane,Chinese herbal medicine,fruit,rabbit meat,honey,and forestry.There is the largest emergy yield in tea and poultry and eggs for Loudi with emergy yield of pork in agricultural ecosystem in Loudi of absolute advantage.Bast fibre plants and palm sheet of Zhangjaijie accounts for the most in Xiangxi Area with economic crops including cotton,sugarcane,tobacco,and tubers are in leading position.Emergy yield of tubers,vegetables,and tobacco of Xiangxi Autonomous Prefecture accounts for the greatest proportion in Xiangxi Area while fruit,tungoiltree,rosin,and bamboo wood are in an advantageous position.⑥Environmental loading ratio(ELR)of agricultural ecosystem in Xiangxi Area is lower than that in Hunan province.Although there is low pressure on environment,there is still fragile eco-environment and if is damaged,it is difficult to recover.Therefore,development in this area costs more prudence.⑦The sustainable development index of agricultural ecosystem in Xiangxi Area is 2.97,which is lower than the average level in Hunan Province of 3.25.The index falls into from 1 to 10,which shows that agricultural ecosystem in Xiangxi Area and agricultural ecosystem in Hunan Province are both energetic with potentiality of development.However,purchasing emergy of Xiangxi Area is relatively low that(assisting emergyinvestment ratio)and its system development performance is rather backward.According to yield of emergy investment and some indexes,measures and suggestions to promote sustainable development of agricultural ecosystem in Xiangxi Area are put forward as follows:①to optimize the system aided emergy investment ratio and improve operation efficiency of agricultural ecosystem in Xiangxi Area;②to reduce the number of farmers and enhance overall quality of farmers;③To take actions that suit local circumstances and develop specialties;④to enhance quality of agricultural products and establish local brand for agricultural products in Xiangxi Area.