Post-processing of biochars to enhance plant growth responses:a review and meta-analysis  

作　　者：Sean C.Thomas 

机构地区：[1]Institute of Forestry and Conservation,University of Toronto,33 Willcocks St.,Toronto,ON M5S 3B3,Canada

出　　处：《Biochar》2021年第4期437-455,共19页生物炭（英文）

基　　金：This work was funded by grants from Natural Science and Engineering Research Council of Canada,with additional support from Haliburton Forest and Wild Life Reserve and the Ontario Mining Association.

摘　　要：A number of processes for post-production treatment of“raw”biochars,including leaching,aeration,grinding or sieving to reduce particle size,and chemical or steam activation,have been suggested as means to enhance biochar effectiveness in agriculture,forestry,and environmental restoration.Here,I review studies on post-production processing methods and their effects on biochar physio-chemical properties and present a meta-analysis of plant growth and yield responses to post-processed vs.“raw”biochars.Data from 23 studies provide a total of 112 comparisons of responses to processed vs.unprocessed biochars,and 103 comparisons allowing assessment of effects relative to biochar particle size;additional 8 published studies involving 32 comparisons provide data on effects of biochar leachates.Overall,post-processed biochars resulted in significantly increased average plant growth responses 14%above those observed with unprocessed biochar.This overall effect was driven by plant growth responses to reduced biochar particle size,and heating/aeration treatments.The assessment of biochar effects by particle size indicates a peak at a particle size of 0.5-1.0 mm.Biochar leachate treatments showed very high heterogeneity among studies and no average growth benefit.I conclude that physiochemical post-processing of biochar offers substantial additional agronomic benefits compared to the use of unprocessed biochar.Further research on post-production treatments effects will be important for biochar utilization to maximize benefits to carbon sequestration and system productivity in agriculture,forestry,and environmental restoration.

关 键 词：Activation GRANULATION LEACHATES Particle size PELLETIZATION POST-PROCESSING 

分 类 号：Q945[生物学—植物学]