Distinct biophysical and chemical mechanisms governing sucrose mineralization and soil organic carbon priming in biochar amended soils:evidence from 10 years of field studies  

作　　者：Haoli Zhang Tao Ma Lili Wang Xiuling Yu Xiaorong Zhao Weida Gao Lukas Van Zwieten Bhupinder Pal Singh Guitong Li Qimei Lin David R.Chadwick Shenggao Lu Jianming Xu Yu Luo David L.Jones Peduruhewa H.Jeewani 

机构地区：[1]College of Land Science and Technology,China Agriculture University,Yuanmingyuan West Road,Beijing 100193,China. [2]Crop Research Institute,Guangxi Agricultural Vocational University,Guangxi,China. [3]Agro-Environmental Protection Institute,Ministry of Agriculture and Rural Affairs,Tianjin 300191,China. [4]Institute of Soil and Water Resources and Environmental Science,Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment,Zhejiang University,Hangzhou 310058,China. [5]School of Environmental and Natural Sciences,Environment Centre Wales,Bangor University,Gwynedd LL572UW,UK. [6]NSW Department of Primary Industries,Wollongbar Primary Industries Institute,Wollongbar,NSW 2477,Australia. [7]Soils West,Centre for Sustainable Farming Systems,Food Futures Institute,Murdoch University,90 South Street,Murdoch,WA 6150,Australia.

出　　处：《Biochar》2024年第1期927-945,共19页生物炭(英文)

基　　金：supported by Key R&D Program of Zhejiang(2022C02046);Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-CSGLCA-202402);Biotechnology and Biological Sciences Research Council(BBSRC)funded Greenhouse Gas Removal Peatland Demonstrator projects(BB/V011561/1).

摘　　要：While many studies have examined the role of biochar in carbon(C)accrual in short-term scale,few have explored the decadal scale influences of biochar on non-biochar C,e.g.,native soil organic C(SOC)and added substrate.To address this knowledge gap,soils were collected from decade-old biochar field trials located in the United Kingdom(Cambisol)and China(Fluvisol),with each site having had three application rates(25-30,50-60 and 75-100 Mg ha^(−1))of biochar plus an unamended Control,applied once in 2009.We assessed physicochemical and microbial properties associated with sucrose(representing the rhizodeposits)mineralization and the priming effect(PE)on native SOC.Here,we showed both soils amended with biochar at the middle application rate(50 Mg ha^(−1)biochar in Cambisol and 60 Mg ha^(−1)biochar in Fluvisol)resulted in greater substrate mineralization.The enhanced accessibility and availability of sucrose to microorganisms,particularly fast-growing bacterial genera like Arenimonas,Spingomonas,and Paenibacillus(r-strategists belonging to the Proteobacteria and Firmicutes phyla,respectively),can be attributed to the improved physicochemical properties of the soil,including pH,porosity,and pore connectivity,as revealed by synchrotron-based micro-CT.Random forest analysis also confirmed the contribution of the microbial diversity and physical properties such as porosity on sucrose mineralization.Biochar at the middle application rate,however,resulted in the lowest PE(0.3 and 0.4 mg of CO_(2)-C g soil−1 in Cambisol and Fluvisol,respectively)after 53 days of incubation.This result might be associated with the fact that the biochar promoted large aggregates formation,which enclosed native SOC in soil macro-aggregates(2-0.25 mm).Our study revealed a diverging pattern between substrate mineralization and SOC priming linked to the biochar application rate.This suggests distinct mechanisms,biophysical and physicochemical,driving the mineralization of non-biochar carbon in a field where biochar was applied a decade b

关 键 词：X-ray CT Porosity Aggregates Microbial community Decadal-scale field study 

分 类 号：S15[农业科学—土壤学]