Effect Of Inoculating Soil Functional Organisms With Pig Manure Composting On Soil Fertilization In Upland Red Soil

The issues of soil fertility and microbial function degradation has been put forward because of the straw burning and the improper handling of pig manure which brings a lot of environmental problems as well.The organic fertilizer of pig manure and straw can improve soil structure and fertility.It is well known that soil functional organisms such as earthworms and nematodes,which they can modify soil physical,chemical and biological properties in terrestrial ecosystem.Phosphate-solubilizing microorganism can transform phosphoric ions adsorbed in soil into soluble phosphate so that it can be easily utilized by the plants.Due to the degradation of soil fertility and ecosystem function of upland red soil in Southern China,based on the long-term experiment,this research investigated that soil biological resource could self-regulate soil ecosystem foundation such as to elevate the crop yield.This research investigated the effects of earthworms,nematodes and phosphate-solubilizing bacteria(PSB)and their interactions on the characters of red soil(physical,chemical and biological properties)and the growth and yield of peanut and sweet potato.Our objective is to further elucidate the role of earthworms,nematodes and PSB in the fertilization of red soil ecosystem,providing scientific basis for the sustainable management of upland red soil ecosystem.The research site is located in Yingtan ecological experiment station of red soil academy sciences.The field experiment designed to have ten treatments including CK(chemical fertilizer);RO(composted pig manure);R(composted pig manure and chemical fertilizer);RN(composted pig manure based chemical fertilizer and nematodes);RE(composted pig manure based chemical fertilizer and earthworms);RP(composted pig manure based chemical fertilizer and phosphate-solubilizing bacteria);RNE(composted pig manure based chemical fertilizer and nematodes and earthworms);RNP(composted pig manure based chemical fertilizer and nematodes and phosphate-solubilizing bacteria);REP(composted pig manure based chemical fertilizer and earthworms and phosphate-solubilizing bacteria);RNEP(composted pig manure based chemical fertilizer and nematodes and earthworms and phosphate-solubilizing bacteria)were conducted to expore the effects of different fertilization managements on soil microbial community,the biological properties of soil,soil nutrient and the crop yield at peanut and sweet potato different stages.The results as follows:1)Inoculated soil functional organisms with composted pig manure could improve the colonization of earthworms and nematodes.The inoculation of PSB,and the combination of them could improve the colonization of PSB at peanut and sweet potato different stages.And the fertilization management also increased the PLFAs content of soil bacteria,fungi,gram negative bacteria,gram positive bacteria and actinomycetes.2)The inoculation of earthworms,nematodes,PSB,and the combination of them could improve the activity of soil microbial community significantly compared with R treatment in different cropping system.But the effect was different in different sampling time.The different microbial ability of carbon source utilization analysis shows:inoculated soil functional organisms could improve the carbon source utilization compared with R treatment.So the fertilization management could improve the microbial ability of carbon source utilization.The inoculation of soil functional organisms altered the microbial community structure.In the same cropping system,the fertilization management enhanced the abundance of bacterial PLFAs(gram-positive and gram-negative)and fungi PLFAs,the RNP treatment reached significant differences in comparison with R(P<0.05).But the fertilization management reduced fungal to bacterial ratio compared with R treatment.3)Regardless of peanut season or sweet potato season,inoculated soil functional organisms with composted pig manure could improve the soil enzyme activity of soil invertase,urease and phosphatase.The inoculation of earthworms,nematodes,PSB did not have a significantly effect on soil basal respiration.And the combination them(RNEP treatment)reached significant differences in comparison with CK and R(P<0.05).4)In the cropping system,the inoculated soil functional organisms(RNP treatment)increased the contents of soil total organic carbon,the RNE and the RNEP treatment increased the contnents of soil available phosphorus,and the RE treatment intreased the contents of soil available potassium(P<0.05).With single or combined inoculation,the root length,area,volume,numbers of tips were improved than the control,and the combined inoculation(RNEP treatment)reached significant differences in comparison with CK and R(P<0.05).The fertilization management could improve the peanut yield,but only the RP and RNE treatment reached significant differences in comparison with CK and R(P<0.05).The fertilization management also could improve the sweet potato yield,but only the RNEP treatment reached significant differences in comparison with CK and R(P<0.05).