Effects Of Biogas Slurry And Biochar On Soil Faunal Community Structure In A Poplar Plantation

Biogas slurry is one kind of liquid residues after anaerobic fermentation of animal and crop waste.It contains a huge number of amino acids,humic acid,indole acetic acid and other substances,it also contains N,P,K as ion state which plants can directly absorbed.But heavy metals and antibiotics in Biogas slurry is a problem.Biochar comes from pyrolysis of crop wastes and other organic materials.Biochar can absorb Biogas slurry and sustained releasing the nutrients.Biochar can also improve soil structure.In this study,we applied four treatments of biogas slurry(CK-0,L-125,M-250,H-375 m³·hm^-2)and biochar(B0-0,B1-40,B2-80,B3-120 t·hm^-2)through randomized Blocks-Nest design in the poplar plantations of the northern Jiangsu Province.This study aimed to reveal the effects of biogas slurry and biochar on soil faunal community structure in different soil layers?i.e.0-10cm,10-25cm and25-40cm?for providing a theoretical basis for the scientific use of biogas slurry and biochar.The result shows that:?1?Treatments of biogas slurry and biochar did not change the ingredient of soil faunal.Prostigmata and Oribatida were still the dominant groups.Treatment of biogas slurry and biochar did not change other groups from common groups to dominant groups.?2?In 3 different soil layers of March,treatment of B1?B2?B3 biochar significantly decreased the soil faunal diversity and group number.Treatment of biogas slurry significantly increased the soil faunal diversity and group number under B0 biochar,in all the 3 soil layers,soil faunal density and group number under treatment of H biogas slurry were significantly higher than those under treatment of CK?L?M biogas slurry.Compare with spring,biogas slurry treatment of M?H decreased the soil faunal group number in summer under biochar treatment B0.Biogas slurry treatment of L?M?H decreased the soil faunal density in summer under biochar treatment B0;But all biogas slurry treatment increased the soil faunal density and group number in summer under biochar treatment of B1?B2?B3.?3?Application of biogas slurry and biochar affected soil faunal by changing soil physicochemical properties.Soil faunal density significantly decreased with soil pH increased,significantly increased with soil bulk density increased;Soil faunal Shannon-winer index significantly increased with soil MBC content increased,significantly decreased with soil NO₃^-N content increased.Soil faunal Simpson index significantly increased with soil bulk density increased,significantly increased with soil MBC content increased,significantly decreased with soil NO₃^-N content increased.In one word,Application of biogas slurry and biochar effected soil faunal by changed the soil physicochemical properties.B0 treatment of biochar and H treatment of biogas slurry significantly increased soil faunal density and group number in spring,but did not change the ingredient of soil faunal.Soil faunal community structure significantly related to soil pH,soil bulk density,soil MBC content and soil NO₃^-N content.