Research On Change Of Soil Organic Carbon Storage,and Bacterial Community Under Different Tillage And Application Organic Fertilization

In order to explore suitable tillage and fertilization patterns,optimize soil structure,improve soil quality and yield of winter wheat and summer corn,this experiment is designed.Based on a six-year field positioning tillage and fertilization experiment,the study field was located at Xuchang,Henan province.The design of two-factor zone was adopted,setting six treatments,which were deep tillage(DT),shallow tillage(ST),zero-tillage(ZT),deep tillage and application of organic fertilizer(DTF),shallow tillage and application of organic fertilizer(STF)and zero-tillage and application of organic fertilizer(ZTF),respectively.This study investigated the effects of different tillage and fertilization on change of soil organic carbon storage,and varity of bacterial community The main conclusions are as follows:1.Tillage and application of organic fertilizer had a significant effect on soil structure.Soil water content in all treatments decreases first,and then increases along with the advancement of the growth period.Soil water content under ZTF was the highest than that of other treatments in the 0-5cm soil layer.DT and DTF could improve the soil moisture content in the 20-60cm soil layer.Soil water content was higher under applying organic fertilizer than that of not applying organic fertilizer under the same tillage method.Soil bulk density increased along with the increase of soil depth,and soil porosity was the opposite.In terms of tillage,soil bulk density under deep tillage was lower than that of shallow tillage,and the soil porosity was greater than that of shallow tillage.Soil bulk density was lower under applying organic fertilizer than that of not applying organic fertilizer under the same tillage method,and the soil porosity was the opposite.2.DTF had a significant effect on wheat yield.Compared with other treatments,grains per spike,1000-grain weight and yield of wheat were the highest under DTF.Under the same tillage method,the yield of wheat and its constituent factors were higher under applying organic fertilizer than that of not applying organic fertilizer.The corn yield was 889.69 kg/hm~2.3.Tillage and application of organic fertilizer had a significant effect on soil organic carbon storage.Compared with other treatments,soil organic carbon and soil active organic carbon content could be improved under zero-tillage and zero-tillage and application of organic fertilizer in the 0-5cm soil layer.The content of soil organic carbon and soil active organic carbon under STF was higher than that of other treatments in the 5-20cm soil layer.The soil organic carbon content and soil active organic carbon content under ZTF were significantly higher than that of STF and DTF(P<0.05).Soil organic carbon and soil activated carbon were higher under applying organic fertilizer than that of not applying organic fertilizer under the same tillage method.4.The relative abundance and diversity of soil bacterial communities were gradually decreased under tillage and application of organic fertilizer.The species coverage of wheat season and maize season was96.7%,93.3%,respectively.The Alpha diversity index of wheat growth period was higher than that of corn growth period.The Simpson index and Shanno index under ZTF were higher than other treatments.Compared with ZTF,the relative abundance of Bacteroidetes under DTF and STF was reduced.Both OTUs and Alpha diversity index were higher under applying organic fertilizer than that of not applying organic fertilizer under the same tillage method.5.Using redundancy analysis,the relationship between environmental factors and bacterial community composition was analyzed.On the first main axis,DOC was the main influencing factor.On the second spindle,MBC was the main influencing factor.DOC was positively correlated with SOM,LOC and MBC.MBC was positively correlated with LOC.MBC was negatively correlated with Proteobacteria but was positively correlated with Firmicutes and Gemmatimonadetes.Bacteroidetes was positively correlated with the content of DOC,SOM and LOC content.The Planctomycetes were positively correlated with MBC,but were negatively correlated with SOM,LOC and DOC.