Effect of Different Tillage Methods and Nitrogen Application Amount on Lime Concretion Black Soil Physical, Microbial Characteristics and Wheat Yield

DU Congyang; YANG Xiwen; WANG Yong; ZHOU Hongmei; WANG Wenliang; HE Dexian

doi:10.15933/j.cnki.1004-3268.2017.08.003

Abstract：Under the condition of returning corn stalks to field,this paper was carried out to investigate the effects of different tillage methods [rotary tillage (RT),deep tillage (DT)] and nitrogen application amount[high nitrogen level(HN),medium nitrogen level(HN),low nitrogen level(LN)] on lime concretion black soil physical properties,microbiological characteristics and wheat yield,with wheat cultivar Aikang 58 as the material.The results showed that compared with RT treatment,soil bulk density of DT treatment significantly decreased in 15-35 cm soil layer,and decreased by 5.9％ and 7.7％ in 15-25 cm and 25-35 cm soil layer respectively;soil water content of DT treatment significantly improved in 15-35 cm soil layer at seedling stage;soil microbial biomass carbon (SMB-C) content of DT treatment increased in 15-25 cm soil layer,soil microbial biomass nitrogen(SMB-N) content of DT treatment increased significantly in 15-25 cm soil layer;activity of soil enzyme of DT treatment significantly increased;grains per spike and 1000-grain weight of DT treatment significantly increased and hence grain yield increased by 7.5％ and 7.7％ in two years.The nitrogen application amount had no significant influence on soil bulk density and water content,nitrogen could inhibite SMB-C content,promote the SMB-N content.Compared with MN and LN treatments,yield of HN treatment increased by 2.3％,2.6％ and 7.2％,6.9％ in two years.Compared with different treatments,DT + HN/MN treatments did well in decreasing soil bulk density,increasing soil water content and SMB-N content,enhancing both soil urease and catalase activities.The yield of DT + HN treatment was the highest,and DT + MN treatment was the second.There was no significant difference between the two treatments.RT + LN treatment was the lowest.Compared with DT + MN and RT + LN treatments,wheat yield of DT + HN treatment increased by 2.7％ and 14.7％ respectively.In summary,DT + MN treatment was the best.