Maize Yield And Soil Water Responses To Cultivating Patterns In Weibei Dry Land

Dryland farming in the semi-arid regions of Weibei dry land is dominated by conventional tillage systems,constrained by low and variable rainfall,and by improper management practices.In this area,persist Six months fallow duration with an average of 30% of entire precipitation of maize production.Conventional tillage(moldboard plowing followed by disc harrowing)method used by farmers results in soil degradation and increases soil evaporation.This study compared the effect of six cultivation pattern with different tillage and fertilization,setting conventional tillage with no fertilization(CT),reduce tillage with no fertilization(NT),subsoiling tillage with no fertilization(ST),conventional tillage with low fertilization(LCT),reduce tillage with high fertilization(HNT),subsoiling tillage with balance fertilization(BST),thousand kernels weight,grain yield and soil water storage were also determined in this research.Results indicated that:(1)At the beginning of fallow period,soil water storage was in different degrees of deficit status,with the insufficient rainfall soil water recoup was not obvious.NT,ST improved soil water storage by 11.91mm、13.66 mm and Water conservation rate improve with 38.5%,56.9% respectively compare with CT at the end of fallow periods.(2)At the growth stage,this resulted in a better water storage during with NT and ST,average improved 27.4mm、15.1mm under CT and certainly improved WUE and PUE.The fertilization with LCT and HNT also had the influence on soil water storage with the increase of soil water consumption 7.8mm、10.9mm compare to CT and NT but BST.(3)Thorough the soil nutrient and plant nutrient uptake we analyzed the nutrient of different cultivating patterns and the results showed that: the conservation tillage with straw retention can effectively improve the soil organic matter content.Simultaneously,the application of chemical fertilizers can effectively promote the formation of soil organic matter,and thus has an effect on soil fertility.Analysis of available nutrient in soils showed that,application of nitrogen and potassium chloride had significant role in nitrogen and phosphorus supplementing,while no significant effect was observed in phosphate,and in our study,the content of available P in soil was mainly affected by tillage,the subsoiling had the stronger capacity to release phosphorus.Furthermore,our results indicated that partial productivity and agronomic efficiency decreased with increments of nitrogen and phosphorus application under the three cultivating patterns,while the decreasing degree had the highest in nitrogen 150kg/hm2 and phosphorus 120kg/hm2.(4)Yield and yield components were also observed in this study.The two year results in a better yield in ST with 492kg/hm2、489kg/hm2 increase than CT.Compared to conventional methods,BST and HNT has similar grain yields but with a higher yields to conventional methods and increase yields with 973 kg/hm2,1260kg/hm2.We can get the result that the grain yield improve accompanied by per area ears and per ear grains improve and BST,HNT has better yield than LCT.