Study On Ecological Effect In Farm System Of Different Amount Of Crop Residues Incorporation

Located on the field in wheat-maize double-cropping area of Huang-Huai-Hai plain from summer in 2001 to 2002, the effect of large amount of crop residue incorporation to soil, atmosphere, and crop were analyzed. Research showed that:1.The effect of different amount of crop of residues to soil temperature appeared in the initial stages after crop residues incorporated in summer, and the more crop residues, the higher the soil temperature in 5cm. But the difference is not significant among treatments. It showed no difference on soil water content.2. The more crop residue incorporated, the more CO2 emitted, which enhanced the C cycling. After three times incorporation, soil respiration in TN and DN increased 14%, 61% than that in NN.3. Whether the crop residue was incorporated and the amount of crop residue incorporated caused different effect to different soil depth. In 2001 the sum of soil biomass of DN and TN increased 21.93%, 19.26% than that of NN. After three times incorporation, the increments were 11%, 22%. The soil biomass increased in 2002 maize, and the range of fluctuation decreased.4.Succesive crop incorporation had no obvious effect on soil urease activity. And the dynamitic of urease activity was the same as soil biomass in three treatments. Urease actived vehemently when crop growing strongly, which would be useful for crop absolving nutrition. After three times incorporation, the sum of urease in DN decreased, but TN increased.5. With the increment of crop incorporation, the seeding in maize decreased, but wheat increased. Yield increased with the incensement of the amount of crop incorporated, but only DN showed signifance. In 2001 the yield increasements of maize were HN 12%, TN 13%, DN 18%, and in 2002 HN 5%, TN4%, NN 10%.