Quality Analysis Of Biochar Derived From Different Sources Biomass And The Effect On Sugarcane Nitrogen Utilization

Biochar has been reported to increase biomass of many crops.However its effect on sugarcane nitrogen dynamics is still not fully understood.Guangxi province is rich in agro-forestry wastes resources.A long-lived problem of sugarcane industry of Guangxi was excessive nitrogen fertilization and lower nitrogen use efficiency(NUE).This study was conducted to screen some good quality biochars apply in sugarcane plant and want to clear the mechanism of biochar impact on sugarcane,by the hypothesis that biochar could promoted the growth and improved NUE of sugarcane.We hope the results could provide some theories basis help in sugarcane breed and cultivation to develop high yield,high sugar content and high NUE.In this study,eight resources biomass:banana Leaf,Banana Stalk,banana pseudo stem,Sugarcane Leaf,Sugarcane Stalk,Cassava Stem,Mulberry Stalk,and Eucalyptus Branch were pyrolyzed at different temperatures among 350?,500 ? and 650 ? and attained 24 types biochar.For the purpose to screen the suitable biochar to applied in sugarcane,the physical and chemical properties and max adsorption capacity of nitrate nitrogen(NO3--N)and ammonia nitrogen(NH4+-N)were analyzed.In this study,N isotope composition,15N was used to facilitate the understanding of the processes involved in the growth,N uptake,distribution,nitrogen use efficient(NUE)of sugarcane(ROC22)and impact on soil properties when biochar is applied.15N and a field experiment were set up to study how the biochar and nitrogen fertilizer impact on two sugarcane varieties(GT11 and B8)which with different NUE.The main results were summarized as follows:1.Biochar material resource and pyrolysis tempertauture significantly affect the physical quality of biochar.Pyrolysis tempertauture significantly affect the physical quality of biochar.Biochar pyroloysised at high temperature has higher surface area and entrance,but lower yield and aperture.But pH value,cation exchange capacity(CEC),content of C,C/H ratio,C/N ratio are higher,while contents of H,N,P,K,and organic mater(OM)are lower.The absorption of biochar NH4+-N and NO3--Nwassignificantly influenced by biochar material sources.Absorption experiments showed that adsorption capacity of NH4+-N of biochar is evidently higher than of Pyrolysised temperature has not significant effect on adsorption capacity of NH4+-N and NO3--N of biochar.Biochar derived from banana leaf,stalk and pseudo stem has equal adsorption capacity of NH4+-N and NO3--N.2.Factor analysis showed that the most important five factors affecting the quality of biochar are chemical facter,physical factor,activation energy factor,nutrient factor and mmoina nitrogen adsorption capacity factor.According to the comprehensive factor socre,we screen some better quality biochars as following:Y24(EB650?)?Y6(BS650?)?Y23(EB500?)?Y17(CS500?)?Y18(CS650?)?Y15(SP650?)?Y3(BL650?)and Y20(MS500?),which had prospect to used as soil amended.3.The effects of biochar on sugarcane vary depending on the varities,growth stages and organ.The impact of biochar on sugarcane biomass showed that ROC22 leaves and roots' growth were sinificantly promoted by biochar,however the effect on the growth of stem was not obvious.Biochar promoted the growth of root,stem and green leaves of GT11 under lower nitrogen fertilizer conditions.Biochar only promoted the growth of stem and tilling stage's root and green leaves of B8.4.Biochar encourage N uptake of sugarcane and promote to absorb more N from nitrogen fertilizer or from soil.Biochar significantly promoted N uptake of ROC22 at tilling stage and elongating stage with a increase of 4.84--10.68%.Biochar mainly promoteds the N uptake of root and stem of GT11 during elongating stage.While B8 olny get the promotion under high nitrogen fertilizer conditions.Compare to pure N fertilizer treatment,biochar increased the proportion of N from fertilizer of GT11 and B8 from 25.12%to 40.79.5.Nitrogen use effecience of sugarcane was enhence by biochar in a certain degree.Biochar mainly promotedthe nitrogen theory yield(PE)and nitrogen fertilizer productivity(PFP)of ROC22 leaves and root during elongating stage and mature stage.Biochar primarily promoted PFP of GT11 root at elongating stage,green leaves at tilling stage under lower N fertililzer contiditions.Biochar primarily promoted PFP of B8 root at tilling stage,green leaves at tilling and mature stage.Biochar promoted stem PE of GT11 at all Growth stage and root PE at mature stage under ower N fertililzer contiditions.But root,stem and leaves PE of B8 were all restain at whole Growth stages.6.Biochar affects the accumulation and distribution of N,P and K in sugarcane and improves soil nutrition.Biochar promoted P distributed to leaf and root of tilling stage and matue stage,stem of mature stage.K was assigned to leaf and stem of mature stage,root of elongate stage.And the other way,biochar obviously increased content of N,P,OM and pH value of soil,but lowed the content of K.Biochar has no effect on electrical conductivity(EC)of soil.7.Biochar could improve the growth,N uptake and nitrogen use effecience of sugarcane under low nitrogen fertilizer applied.The field experiment showed that biochar slightly increasedthe seedling rate of GT11 and B8,but has not obvious effect on plant height,stem diameter and number of productive tiller.Biochar slightly increasing the sugar yield of GT11,but has no obvious effect on yield of GT11&B8.Biochar inhibited the nitrogen accumulation of GT11 stem,especially under high N fertilizer conditions,but the accumulation of green leaves was slightly increased.B8 showed the opposite pattern.Biochar has no obvious effects on stem PFP of GT11&B8.Green eaves of GT11 get promoted by biochar while B8 was suppressed.Biochar only promoted the stem PE of GT11 under lower N fertililzer contiditions.While PE of B8 all was hampered by biochar.