Screening Of Degrading Weathered Coal Strains And Study On The Efficacy Of Liquid Film

With the development of agricultural industrialization in China and the increasing environmental pollution,how to solve the problem of "white pollution" caused by plastic mulch has become an urgent hot topic for researchers.However,the weathered coal resources in China are widely distributed and have large reserves,but because of their low activity,they are difficult to be widely used in agriculture and other fields.Therefore,this study takes the weathered coal rich in humic acid as the main raw material to prepare the biodegradable liquid film of weathered coal,which can be used to solve the "white pollution",promote the growth of crops.By screening the strains that can degrade weathered coal and studying the fermentation conditions of its medium pH,temperature,time and inoculation quantity,it provides certain theoretical basis for increasing the content of free humic acid and further application,and also lays a theoretical foundation for realizing the resource utilization of weathered coal.The specific results of the study are as follows:(1)Eighteen strains of decomposing bacteria capable of degrading weathered coal and increasing the content of free humic acid were screened out from the weathered coal and soil,among which five strains had better degradation ability.Combined with the original actinomycetes(CG5)that can degrade weathered coal in the research group,after determining the content of free humic acid in residual coal and antagonizing test,three strains of degradation bacteria combination of weathered coal were selected.(2)According to the best proportion of mixed bacterial solution,quantitative weathered coal degrading bacteria were added to liquid film,so as to improve the degradation effect of liquid film.The effects of different weathered coal content on the water retention performance of liquid film were studied.The results showed that 30%weathered coal had the best water retention effect,and the water loss decreased by 31.49%compared with the non-film mulching.(3)The influence of liquid fild mulching on soil microbial community structure was evaluated by the change of soil microbial quantity.The results showed that the number of bacteria,fungi,and actinomycetes increased by 222.3%,129%and 113.2%respectively.(4)Determination of soil nutrients before and after mulching.The results showed that liquid mulching also had a promoting effect on soil nutrient content.Compared with CK,soil total nitrogen content increased by 0.17%,total phosphorus content increased by 0.1882%,total potassium content increased by 0.844%,and soil organic matter content increased by 6.64 g/kg.(5)Plant growth test.Finally,the effects of spraying liquid mulch on crop germination rate and plant height were compared.The results showed that spraying liquid film could promote the germination rate and plant height of sweet sorghum and maize.