Effects Of Autumn Mulching On Soil Environment And Growth Of Spring Maize

This study analyzed the effects of autumn mulching on soil environment, spring maize growth and yield, through mulching plastic film and straw after the rain in autumn. The main results are summarized as follows:1. Different mulching materials showed different effects on temperature.In the early growth stage of spring maize, plastic film mulch significantly increased soil temperature, the difference decreased with the growth and development. Straw mulch significantly decreased the soil temperature, and the difference increased with the increas of straw covering quantity, the difference between straw mulch and control were significant during the whole growing season.2. Autumn mulching can significantly improve the soil water storage at planting time. Compared with control, the flat-film mulching, ridge-film mulching, straw mulching3000kg/hm2. straw mulching6000kg/hm2and straw mulching9000kg/hm2significantly increased the soil water storage by21.22,20.49,18.37and19.5mm respectively. In the spring maize growth period, different mulching materials had different effect on the soil water storage in0～200cm of soil layer. The flat-film mulching, ridge-film mulching, straw mulching6000kg/hm and9000kg/hm2can significantly increase soil water storage (0～200cm). Compared with control, flat-film mulching and ridge-film mulching increased the average soil water storage by15.57and15.73mm, respectively, at sowing-bell-mouthing stage. Straw mulching6000kg/hm2and9000kg/hm2increased the average soil water storage by12.05and12.73mm, respectively, compared with control. The soil water storage under straw mulch treatments was higher than the control at the late maize growth stage, while the differences among them were not significant. Compared with control, flat-film mulch and ridge-film mulch decreased the average soil water storage by6.70and3.5mm at the heading～filling stage.3. The soil available K、available P and available N contents under different mulching materials were higher than the control after maize harvest, as manifested in20cm soil layer, and the effect gradually decreased with the increase of soil depth. The soil nutrient content increased with the increase of straw mulch amount, while different mulching materials had not significant effects on soil total N content. 4. Different mulching materials improved the photosynthetic rate, transpiration rate, stomata conductance and intercellular CO2concentration. The photosynthetic rate and transpiration rate under straw mulch were significantly higher than the control during the entire growth season. There were no significant differences in the photosynthetic rate, transpiration rate and intercellular CO2concentration compared with plastic film and the control at filling stage. In jointing stage, the difference of intercellular CO2concentration between stalk mulch and the control were not significant. The stomata conductance of straw mulch had no significant differences compared with the control in bell-mouthing. The photosynthetic indexes of stalk mulching3000kg/hm2had no significant differences compared with the control during the entire growth season.5. The mulching treatment could accelerate the emergence of maize and the emerging stage with plastic film and straw mulch treatments advanced5d and2d compared with the control. The whole growing season of plastic film treatment shortened11d compared with the control, but there were no significant differences between stalk mulch and the control.6. Plastic film treatment could significantly enhance dry biomass. plant height and leaf area at the early stage of maize and stalk mulch treatment could significantly enhance these in the later growth stage. The mulching treatment could significantly increase ear length. ear diameter, and hundred-kernel weight, and reduced the rate of bald war. Plastic film could significantly increase crop yield and water use efficiency, and the maize yield and water use efficiency under flat-film mulching and ridge-film mulching were increased by14.59%,13.94%,11.04%, and11.11%compared with the control, and while the effect of stalk mulch treatment on maize yield was not significant compared with the control.