| Emergy input-output, macro-economic benefits, environmental pressure and net emergy output of maize, soybean and rice in Jilin province and its typical areas are analyzed applying emergy theory and methods in this paper, and comparative advantage analysis model of these areas is established based on above analysis, and some case studies are carried out. The main results are following:(1) Net emergy output ratio and emergy input ratio of cropping system in Jilin province are both higher,they are 2.03 and 6.18.This shows that production technology level is high while its environmental pressure is severe. Proportion of environmental emergy is 14% of total emergy, Proportion of purchase emergy is 86%,among purchase emergy, Proportion of industrial assistant emergy is 85%, among industrial assistant emergy, the propotion of fertilizer is the highest, this shows that intenvisim degree of crop production in Jilin province is higher.(2) Main crops emergy comparative results. Net emergy output ratio is soybean (1.63) > rice (1.13) > maize (0.98), it showed that soybean productivity is higher, and maize output-input ratio is unreasonable; environmental pressure is maize (8.27) > rice (7.59) > soybean (4.39), it showed that environmental pressure of soybean is smallest; macro-economic benefits is maize (6659yuan/hm2) > rice (6041yuan/hm ) > soybean (3805.5yuan/hm ), and according market price the macro-economic benefits is 4582.5Yuan/hm2, 3904Yuan/hm2 and 8187 Yuan/hm2, it showed that market prices of maize is insufficient to compensate emergy cost, so ecological compensate mechanism should be setup and compensate amount of maize are 2076.5Yuan/hm2. Because market price of soybean and rice are higher than macro-economic benefits, the ecological compensation can achieved through market.(3) Emergy comparative results of maize in different ecological areas. Agricultural intension in Wangqing, Shulan, Gongzhuling and Da'an are higher, emergy flows of maize are mainly purchase emergy, and their purchase emergy proportions are 85.02%, 82.90%, 89.24% and 89.49% of total emergy; net emergy output are 0.57, 1.62, 1.25 and 0.70, and those of Shulan and Gongzhuling are higher than province average. Environmental pressure in Wangqing, Shulan, Gongzhuling and Da'an are 6.37, 5.83, 9.27 and 16.99, and those of Gongzhuling and Da'an are higher than province average.(4) Emergy comparative results of soybean in different ecological areas. Emergy flows of soybean in Wangqing, Shulan and Gongzhuling are mainly purchase emergy, and their purchase emergy proportions are 77.46%, 73.85% and 78.74% of total emergy, it showed that intension of soybean is higher; industrial assistant emergy proportion are 57.33%, 44.51% and 56.06% of total emergy, and they are lower than maize and rice, and it also showed that industrial assistant emergy proportion in Shulan is lower than the other areas; net emergy output are 1.24, 3.06 and 2.05(the province average is 1.63), and it showed that market competition in Shulan is strongest. Environmental pressure are3.61, 3.15 and 4.51, and those of Gongzhuling is 4.39 higher than province average.(5) Emergy comparative results of rice in different ecological areas. Emergy flows of rice in Wangqing, Shulan and Gongzhuling are mainly purchase emergy, and their purchase emergy proportions are 84.70%, 84.18% and 90.99% of total emergy, purchase emergy of Gongzhuling is higher than provincial average; industrial assistant emergy proportion are 68.14%, 66.83% and 79.27% of total emergy, and Gongzhuling is higher than provincial average, and it showed its higher intension; net emergy output are 0.90, 2.01 and 1.14, and it showed stronger market competition in Shulan. Emergy input are 5.86, 5.66 and 10.67, and those of Wangqing and Shulan are lower than province average, it showed lower costs and stronger market competition in these areas.(6) Setup comparative advantage analysis model based on emergy theory. The analysis results show in the following: comparative advantage index of maize production is Shulan (2.01)>Gongzhuling (1.
|
PDF Full Text Request