Effects Of Biochar Application On Bacterial Diversity And Physical-Chemical Properties In Fluvor-aquic Soil Of North China

Biochar is a by-product of biomass pyrolysis, incorporation of it into soil is currently being promoted as one of the tools that could be deployed to combat anthropogenically induced increases in atmospheric CO2concentrations. It is generally accepted that biochar-C is largely unavailable to soil microbes but changes in soil physicochemical properties and the introduction of metabolically available labile-C compounds associated with the biochar may shift the soil microbial community structure. Six treatments were investigated:T1(no biochar and urea-N); T2(no biochar+225kg urea-N-hm-2);T3(7.5t-hm-2biochar+225kg urea-N·hm2); T4(15t·hmm2biochar+225kg urea-N-hm2); T5(25t-hm2biochar+225kg urea-Nhm2);T6(30thm-2biochar+225kg urea-N-hm2). The biochar used was obtained from peanut shells by pyrolysis at300℃. All treatments replicated four times,and arranged in randomized blocks design.The results show that:(1) With the increase of biomass, the soil nutrient content is improved. Biochar could significantly increase soil organic matter, and has appreciable effect with soil physical-chemical properties.(2) In the event that biochar becomes widely applied to agricultural soils as a soil conditioner. A field experiment was designed to investigate temporal changes bacterial diversity in fluvor-aquic soil of North China. The DGGE-cloning sequencing method was used to study the bacterial diversity presence and absence of biochar. The results showed that the bands were increased4or5in16S rDNA DGGE fingerprints while comparing biochar amended soils with controls, Changes in bacterial family abundances were included that Shannon-Wiener diversity index and Pielou evenness index decreased by11.49%-12.98%,14.14%-16.47%, where the biochar had a negative influence. Cluster analysis demonstrated that fingerprint of all treatments were different with similarity being60%, there was a decreased trend on the similarity of bacterial community composition with increased biochar application rate.13bands were selected from DGGE gel and DGGE-cloning sequenced, which showed that they are bacterial DNA sequences. In treatment T5and T6, band p, band q and band r had been found, which represented unclassified bacterial, but band e and band f had been disappeared, which represented Proteobacteria. Results from this study indicate that biochar promotes new bacterial species, simultaneously, inhibits customary bacterial, changes bacterial community composition, decreases of diversity index and evenness index of soil bacterial community through increasing differences of bacterial families structure.(3) With the increase of biomass, soil microbial diversity is on the increase. A WCD is also increased.