Natural Precipitation Redistribution in the Cultivation of Whole Plastic-film Mulching on Double Ridges Ditch Sowing

Abstract：In the study,we determined the redistribution of the natural precipitation in the flat blocks of the rain fed agricultural region of east Gansu Province for corn fields,and analyzed and compared the effects on the effective infiltration of natural precipitation in the corn＇s three kinds of cultivation.The results showed that： The effects of the natural precipitation＇s collection was 72.46%～87.95% in the cultivation of whole plastic-film mulching on double ridges ditch sowing,but it was poorer in the process of light snow and rain and the precipitation was lower than 1mm,and it also was affected on the low temperature,frozen and snowfalls in February;The effects of the natural precipitation＇s infiltration was 61.44%～80.06%,but it had great influence by the process of light snow and rain,and torrential rain,it was also affected on the low temperature,frozen and snowfall in February and high temperature and drought in June and July.The cultivation of the whole plastic-film mulching on double ridges ditch sowing would make more precipitation that would be accepted to infiltrate into the small region where the plant roots could directly use（the layer of lower than that the seeding hole）,and the precipitation＇s infiltration of the per unit area was respectively increased by 11.76～43.30 times and 52.60～229.77 times than the culture of half plastic-film mulching on the ridge and the open field.The water would infiltrate more deeply,but the total amount of the main distribution area where the plant roots would use the infiltration was not much higher than the cultivations of the other two kinds.