| The long-term incompatibility between ecosystem restoration and production of agriculture and animal husbandry in ecotone of North China is the radical reason hampering its sustainable development and to found the coupling mechanism of agriculture and animal husbandry system for advancing the agro-ecosystem productivity seems to be the ideal way of its developing harmoniously. The aim of this paper is to evaluate the actual ecosystem productivity and discuss the regional developing issue of the ecotone based on the typical case study with some prevalent approach. The region for cases studies includes two typical counties, Ansai county of Shaanxi province, Wuchuan county of Inner Mongolia, one watershed named Zhifanggou located in Ansai county with over 20 yrs artificial comprehensive ecological harness, and two different farmers household .The results are as follows.1. This paper first puts forward the framework of agro-ecosystem productivity constituted by primary productivity .secondary productivity .economic productivity of peasants household , ecosystem servicesproductivity and their evaluation indices, in which the approach of emergy analysis and ecosystem service was introduced and applied after being revised. This framework of agro-ecosystem productivity evaluation is expected to be an innovative attempt comparing to the similar research method before.2. The emergy evaluation results show that (1) The primary system productivity have risen greatly since 1990 in this region. As far as total emergy output ,Ansai county increased 34.5 percent in 2000 than in 1990,and Wuchuan county increased 36.1 percent in 2000 than in 1990,however, the primary productivity was still in the stage of traditional lower input. The emergy of industrial auxiliary energy increased but its percent in total input was less than 10 percent .The input of manpower emergy was above 60 percent of the total emergy input, and the non industrial emergy input was above 90 percent of the total emergy input. So, the net emergy yield ratio was lower, and the average ratio of emergy output to emergy input was less than 1.0. (2) The secondary productivity increases quickly in this area, however the effect of coupling between agriculture and animal husbandry is poor. The radical reason of lower ecosystem productivity and disharmonic developing in this ecotone is the improper configuration inner animal husbandry for example of Ansai county and big animal scale exceeding the threshold of the primary productivity for example of Wuchuan county, which above-mentioned leads to the fact that coupling mechanism between agriculture and animal husbandry system has not been established, and agriculture and animal husbandry is still in the state of disharmonic on the whole.3. With respect to the ecosystem service, the results show that the value of ecosystem service of Ansai county and Wuchuan county is 170 times and 151 times of their product value respectively, which reveals that even in fragile area the ecosystem services are do existed and have great value, mat definitely could provide important support to the strategy of restoring vegetation whereas reducing field for raising system productivity. However, the service function is poor and is not consistent with our expecting. The value of containing soil and water is only 5.1 percent and 0.7 percent in total ecosystem value respectively in Ansai county and Wuchuan county, however in Zhifanggou valley the ration gets to 60.3 percent. So some measures of increasing the vegetation and strengthening the service function should be taken continuingly.4. The practical income of farmers increases to some extent, but the emergy analysis of typical peasant household shows that the emergy input is in lower level with the fact of the imbalance existed in grass and animals of peasant household and overloading severely in animal husbandry. Their income is based on the great pressure to the environment. Population in different scale all exceeds the lower limit of carrying capacity of renewable re...
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