保护性耕作小麦—玉米农田生态系统能流特点的研究

Energy Flow in Winter Wheat Corn Farmland Ecosystem Under Conservational Tillage Sys- tem

通过在黑龙港地区主要土壤类型壤质潮土上连续3年的耕作试验,研究在不同耕作条件下农田生态系统的能流特点与能量分配的合理性。结果表明,与传统耕作制度相比,保护性耕作(免耕)能够明显提高小麦—玉米一年两作农田生态系统的能量转化率,能量投产比间的差异显著(P<0.01);不同耕作农田生态系统的熵变和自由能绝对值的差异均无统计学意义,但在一定程度上表明免耕增强了农田生态系统的有序性,从而提高了系统的相对生产力。

The study on the utilization coefficience of input energy in farmland ecosystem is an important part in sustainable agriculture research. The objective of this study was to determine the characteristics of energy flow in farmland ecosystem in which two crops (winter wheat and corn)were planted around a year under four tillage systems. The experiment was carried out in Hengshui,Hebei on a loam soil from 1992 to 1994. The results indicated that there were no significant differences between output energy, and the changes in entropy of the winter wheat and corn farmland ecosystems under the four tillage systems. But input energy utilization rate of the zero tillage system was significantly higher than that of the other three tillage systems.