| In order to determine a reasonable tillage system, a two-year experiment was conducted in Ansai, northern Shaanxi to test soil unease activity and sucrase activity of the fields of Glycine max L, Zea mays L, Semen Phaseoli and Solanum tuberosum Linn in the treatments of the tillage fertilizer (CF) , tilling organic manure (CM) , tillage no fertilizer (CN) ;no-till fertilizer (NF) , no-till organic manure (NM) , no-tillage no fertilizer (NN) in loess hilly and gully region.The results showed that: in the flowering stage soil unease activity of soybean and maize fields increased, but sucrase activity decreased, while those of adzuki bean and potato were opposite.After harvest time, soil unease activity and sucrase activity of maize field increased by 83%, while soil unease activity of potato, adzuki bean and soybean fields decreased, and the decreasing range was above 10% and sucrase activity increased by over 40%.From flowering stage to harvest time, no tillage reduced soil unease activity but increased sucrase activity.The effect of environmental protection was that the two kinds of soil enzyme showed high activity in the growth period but low activity after harvest, which can improve fertilizer efficiency in crop growth period and reduce the emission of greenhouse gas after harvest. |