不同海拔高度下恩施烟田的 物质流、能量流和价值流特征.

[Objective]The illumination, temperature and production efficiency of the ecological system in the tobacco field were significantly affected by the altitude. [Method]The article focused on the production of 32 typical peasant households in Enshi of Hubei province, the in­put and output of nutrients, energy and economic benefits in die production process of diree different altitude flue-cured tobacco(500 -900. 900 - 1200,1200 - 1500 m) were studied, and the characters of the material, energy and value flow of different altitudes were analyzed. [Result] In all the altitude of tobacco area, there were needs for controlling the amounts of N, P fertilizers and increasing the fertilizer appli­cation efficiency. In the construction of energy input, the labor energy was the highest among the energy components, and the fertilizer ener­gy followed. With the increase of altitude, the P, K and energy input to output ratio increased, and the N and value input to output ratio in­creased at first and then decreased. [Conclusion]The ratios of material, energy and value input to output at the altitude of 500 to 900 meters tobacco were minimum, and the altitude of 900 to 1500 meters was better to improve the ratio of nutrients input to output, energy efficient utilization and the ratio of value input to output. [ABSTRACT FROM AUTHOR]