Study On Influencing Factors And Ecological Response Of Returning Corn Stalk To Soil

There are the abundant crop straw resources in China,and how to degrade straw quickly is a current problem to be solved.To explore the rapid degradation of corn stalks,this study used two four-factor three-level orthogonal experiments to explore the influence of the straw-degrading bacteria,carbon-to-nitrogen ratio,straw length,soil depth and nitrogen source type,metal ions,straw weight on the return of corn stalks to the field.In the meantime,the ecological effects of the farmland are explored through various indicators in the return of corn stalks to the field,by which the main factors affecting the return of corn stalks to the field are made to provide a theoretical basis for the sustainable return of corn stalks,and also develop new ideas of green and efficient return of corn stalks to the field.The main results of this study are as follows:In order to explore the effects of straw-degrading bacteria,carbon-nitrogen ratio,straw length,and soil depth on corn stalks returning to the field,the four-factor three-level orthogonal experiment have been adopted to conclude and rank the influencing factors of corn stalks returning to the field: straw-degrading bacteria,straw Length,carbon to nitrogen ratio,soil depth.Straw degrading bacteria showed significant differences in various indicators including straw degradation rate,stem thickness,ear length,bald tip length,ear weight,thousand-grain weight,and soil enzyme activity.It is concluded that the best factor level combination for returning corn stalks to the field is A2B3C1D3,that is,the concentration of straw degrading bacteria is 0.5×106 cfu/m L,the ratio of carbon to nitrogen is 2%,the length of straw is 2 cm,and the soil depth is 25 cm.Based on the analysis of variance of all indicators,the order of the influencing factors of returning corn stalks to the field is: straw-degrading bacteria,straw length,carbon-nitrogen ratio,and soil depth.In order to research the effects of nitrogen source types,metal ions,straw weight,and quicklime on corn stalks returning to the field,four-factor three-level orthogonal experiment has been used,which have found that the best combination of factor levels in corn stalks returning to the field is A2B1C3D2,namely,the nitrogen source is Ammonium sulfate and metal ions are treated with magnesium sulfate,straw weight30 g,and 0.6% quicklime.Based on the analysis of variance of multiple indicators,the influencing factors of corn stalk returning to the field are ranked as follows: straw weight,metal ions,quicklime,and nitrogen source type.On the basis of the results of two orthogonal experiments,the recommended combination when returning corn stalks to the field in agricultural production is that the concentration of straw degrading bacteria is 0.5×106 cfu/m L,the carbon to nitrogen ratio is 2%,the length of straw is 2 cm,and the soil depth is 25 cm,the nitrogen source type is ammonium sulfate,the metal ion is magnesium sulfate,the straw weight is 30 g,and the quicklime is 0.6%.Under this combined treatment,the degradation efficiency of corn straw and the ecological effect in the field can achieve better results.