Study On The Effect Of Corn Straw On Main Physical And Chemical Characteristics Of Black Soil

The soil nitrogen and carbon are the nutritive elements of crops grow. The soil carbon and nitrogen not only be related with the productivity of soil, but also have close contacting with the change of the greenhouse gas in atmospheric. To make clear about the relationship between soil carbon and nitrogen, which will help to improve the level of soil carbon and nitrogen.The experiment was carried out on cultivation corn in experimental base of the Northeast Agricultural University. The purpose of the study was to understand how soil fertility maintaining practices, such as’trichotomy" Big Ridge subsoiling with the return of crop straw to the field, the use of organic fertilizers, and the adding of different microbial agents affected the dynamics of soil microbial biomass carbon (MBC) content. Five treatments of fertility maintaining practices in the field were chosen (where the symbol"+" means combination application):①Traditional small ridge (TR);②Big Ridge subsoiling (BR);③Big Ridge subsoiling+organic fertilizers (BO);④Big Ridge subsoiling+corn straw (BC);⑤Big Ridge subsoiling+corn straw+cellulose decomposing bacteria agents (BCC);⑥Big Ridge subsoiling+corn straw+surface active agents (BCS);⑦Big Ridge subsoiling+corn straw+surface active agents+cellulose decomposing bacteria agents (BCSC).The main conclusions are shown as follow:The treatment of BC’s soil bulk density was significantly lower than TR, but its soil porosity was significantly higher than TR. BC’s soil bulk density and porosity can be better ensure the requirements of the crops. BC or BCSC’s soil organic matter content also be increased on the basis of the straw and Big Ridge, but its did not reach significant level,The treatment of BCS significantly increased the soil organic matter content by13.43%in the maturity of the corn.The total soil nitrogen content was relatively reduced in straw decomposition process. Microbial biomass nitrogen and microbial biomass carbon content of big ridge treatment have been promoted and the effects reached a significant level in the jointing stage、 filling stage and maturity stage.The soil microbial biomass nitrogen content of BO treatment has been improved significantly in n whole growth period of corn compared with the BR.At the same time, the effects of cellulose decomposing bacteria agents and surface active agent treatments on soil microbial biomass carbon and nitrogen content influence also reached a significant level on the basis of the corn straw returning. The soil soluble carbon content was highest in the jointing stage and grain filling stage of the corn between different treatments.BC’s soil soluble carbon content was significantly higher than BR treatment. But the impact of BCC on soil soluble carbon content was not significant. The soil inorganic nitrogen content was significant difference between different treatments during the first two stage s of the corn growth. The performance of the BR and BC’s soil inorganic nitrogen content was significantly higher than CK, But the last three periods in each treatments were no significant differences.