Study On The Effect Of Biochar Based Phosphate Fertilizer On Leymus Chinensis Growth And Soil Physicochemical Properties In Waste Dump

The dump formed by the mining of open-pit coal mine has brought a series of ecological problems.The soil structure and physicochemical properties of the dump are worse than those of the natural grassland,so it is difficult for plants to build,survive and grow.Therefore,it is necessary to carry out the research on vegetation restoration scheme of waste dump.In this paper,through the indoor pot experiment,taking Leymus chinensis as the characteristic plant species,we simulated the vegetation growth,soil physical and chemical properties and phosphorus loss of the dump under the conditions of applying different concentrations of phosphate fertilizer,including phosphate rock powder,superphosphate and biochar based phosphate fertilizer combined with biochar.The main conclusions are as follows(1)In this experiment,different fertilization methods,including different concentrations of phosphate rock powder,calcium persulfate,biochar,carbon based phosphate rock powder and carbon based calcium superphosphate,can promote the increase of plant height,fresh weight and dry weight of Leymus chinensis in the dump;in general,compared with phosphate rock powder and biochar,the values of plant height,fresh weight and dry weight of Leymus chinensis in different phosphorus concentrations are different At 5 mg/kg P concentration,the effect of carbon based Superphosphate on the growth of Leymus chinensis was greater than that of superphosphate and biochar in soil environment,but at 10 mg/kg and 20 mg/kg P concentration,the effect of carbon based Superphosphate on the growth of Leymus chinensis was slightly lower than that of superphosphate and biochar;carbon based phosphate rock powder and carbon based superphosphate Calcium can promote the growth of Leymus chinensis,but there is no significant difference between them.(2)Different fertilization methods had no significant effect on soil p H,but could significantly increase the concentrations of soil organic matter,soil available phosphorus and soil nitrogen.Compared with phosphate rock powder and biochar,carbon based phosphate rock powder fertilizer significantly increased the contents of soil organic matter,available phosphorus and total nitrogen,but decreased the contents of soluble organic carbon(DOC)and soil available nitrogen.