Magnesium-doped biochars increase soil phosphorus availability by regulating phosphorus retention,microbial solubilization and mineralization  

作　　者：Muhammed Mustapha Ibrahim Huiying Lin Zhaofeng Chang Zhimin Li Asif Riaz Enqing Hou 

机构地区：[1]Key Laboratory of National Forestry and Grassland Administration On Plant Conservation and Utilization in Southern China and Guangdong Provincial Key Laboratory of Applied Botany,South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650,China. [2]Key Research Laboratory of Soil Ecosystem Health and Regulation,College of Resources and Environment,Fujian Agriculture and Forestry University,Fuzhou 350002,Fujian,China

出　　处：《Biochar》2024年第1期1213-1229,共17页生物炭(英文)

基　　金：support was received from the Guangdong Basic and Applied Basic Research Foundation(2022B1515020014);China Postdoctoral Science Foundation(2023M743544);Fujian Forestry Science and Technology Promotion Project(2020TG17);the University-Industry Cooperation Project of Fujian Province(2021N5002).

摘　　要：Despite fertilization efforts,phosphorus(P)availability in soils remains a major constraint to global plant productivity.Soil incorporation of biochar could promote soil P availability but its effects remain uncertain.To attain further improvements in soil P availability with biochar,we developed,characterized,and evaluated magnesium-oxide(MgO)and sepiolite(Mg4Si6O15(OH)2·6H2O)-functionalized biochars with optimized P retention/release capacity.Field-based application of these biochars for improving P availability and their mechanisms during three growth stages of maize was investigated.We further leveraged next-generation sequencing to unravel their impacts on the plant growth-stage shifts in soil functional genes regulating P availability.Results showed insignificant variation in P availability between single super phosphate fertilization(F)and its combination with raw biochar(BF).However,the occurrence of Mg-bound minerals on the optimized biochars’surface adjusted its surface charges and properties and improved the retention and slow release of inorganic P.Compared to BF,available P(AP)was 26.5%and 19.1%higher during the 12-leaf stage and blister stage,respectively,under MgO-optimized biochar+F treatment(MgOBF),and 15.5%higher under sepiolite-biochar+F(SBF)during maize physiological maturity.Cumulatively,AP was 15.6%and 13.2%higher in MgOBF and SBF relative to BF.Hence,plant biomass,grain yield,and P uptake were highest in MgOBF and SBF,respectively at harvest.Optimized-biochar amendment stimulated microbial 16SrRNA gene diversity and suppressed the expression of P starvation response and P uptake and transport-related genes while stimulating P solubilization and mineralization genes.Thus,the optimized biochars promoted P availability via the combined processes of slow-release of retained phosphates,while inducing the microbial solubilization and mineralization of inorganic and organic P,respectively.Our study advances strategies for reducing cropland P limitation and reveals the potential of optimized bio

关 键 词：Phosphorus limitation CROPLAND Functional genes Field crops Maize production 

分 类 号：S15[农业科学—土壤学]