甘肃河西地区农田生态系统能量投入产出及效率分析  

Analysis of input and output of energy and energy efficiency in cropland-ecosystem of Hexi district, Gansu

作　　者：魏小红[1] 蔺海明[1] 胡恒觉[1] 

机构地区：[1]甘肃农业大学农学系,甘肃兰州730070

出　　处：《草业学报》2001年第3期79-84,共6页Acta Prataculturae Sinica

摘　　要：应用生态学能流研究方法 ,对河西 4 5年农田系统能量输入输出及效率进行了力能学分析。结果表明 ,总投能逐年增加 ,1994年总投能最高的县为张掖市 (131.5 9× 10 3MJ/ hm2 )。无机能在总投能中所占比例依次呈现出平稳、快速、缓慢增长的变化趋势 ,天祝县无机能投入远远低于其它县市 ,1994年为总投能的 18%。总产能呈现出递增趋势 ,但自 2 0世纪 80年代中期以后增长缓慢 ,4 5年来不同县市总产能增加以酒泉市和张掖市最大 ,1994年酒泉市和张掖市总产能分别为2 35 .93× 10 3和 2 32 .38× 10 3MJ/ hm2 。 4 5年中 ,能量产投比出现 2个高峰和 1个低谷 ,自 80年代高峰过后 ,大多数县市产投比下降 ,其中天祝县产投比最低 ,1994年仅为 0 .83。 7县市中酒泉市、民乐县、天祝县、武威市、张掖市农田单位面积投能分别超出其临界值 :5 .66× 10 3、4 .61× 10 3、8.73× 10 3、15 .91× 10 3和 36.84× 10 3MJ/ hm2。The input and output of energy and energy efficiency in cropland-ecosystem of Hexi district, Gansu, for 45 years were analyzed by using method of energy flowing of ecology. The results showed that total input energy to the system increased annually. The maximum of input energy was found in Zhangye city (131.59×103 MJ/hm2) in 1994. From 1949 to 1994, proportion of inorganic in the total energy appeared a tendency to flat-rapid -slow increasing, and the lowest one was found in Tianzhu (only 18% in 1994). The total output energy increased annually as well, but its trends went slowly after mid-1980's. The total of output energy in Zhangye and Jiuquan increased faster than others, there were 235.93×103 and 232.38×103 MJ/hm2 respectively in 1994. The rate of energy output /input appeared two peaks and one valley. In most counties the rate of output/input reduced after 1985.The smallest rate was found in Tianzhu with only 0.83. The input energy in Jiuquan, Minle,Tianzhu, Wuwei and Zhangye went beyond their critical values of 5.66×103, 4.61×103,8.73×103,15.91×103and 36.84×103 MJ/hm2,respectively.

关 键 词：农田系统 力能学 产投比 甘肃河西 

分 类 号：S181[农业科学—农业基础科学]