Abstract:
According to the characteristics of different planting ecological areas in Heilongjiang Province, different straw returning tillage modes were selected to analyze and discuss the indexes, such as soil moisture content, temperature, corn growth and yield under different modes.The results showed that dual effect of straw returning on soil temperature increasing or decreasing was affected by different ecological regions and different growth stages.Additionally, in the humid area, the soil moisture content under straw burying returning increased compared with that without straw returning to the field, but did not reach the significant difference level.The impact on the plant was mainly reflected in the seedling stage and jointing stage, and the final yield increased by 4.2%.In the semi-humid area, the soil moisture content of straw mulching was the highest in each growth period.Compared with CK,the yields of straw crushing and mixing, straw burying and straw mulching were increased by 4.7%,4.2% and 0.6%,respectively.In the semi-arid area, straw mulching, no tillage for two years and subsoiling for one year with straw returning had little effect on soil agitation and maintained relatively high soil moisture content.In the whole growth period, the aboveground dry weight of no tillage for two years and subsoiling for one year with straw returning were always greater than that of other treatments.The yield performance was as follows: No tillage for two years and subsoiling for one year with straw returning>straw crushing and mixing returning>straw burying returning>straw mulching>CK,which increased by 8.1%,7.7%,7.2% and 1.8% respectively compared with CK.To sum up, it is beneficial to increase production by straw burying returning in humid area, while the mode of straw crushing and mixing returning, no tillage for two years and subsoiling for one year with straw returning is more suitable to improve yield in semi humid and semi-arid areas, respectively.