生物炭制备工艺及其对土壤特性影响的研究进展OA

Biochar exhibits multidimensional effects of soil conditioning,nutrient retention,and quality enhancement in soil improvement.This article systematically reviewed the regulatory laws of raw material types,pyrolysis temperature,heating rate,and residence time on the physicochemical properties of biochar and their impact mechanisms on soil properties.Existing studies had shown that raw materials determined the fundamental properties of biochar,with woody biochar having the highest yield and optimal pore structure,which was beneficial for water and fertilizer retention;livestock manure biochar was rich in nutrients and was a high-quality slow-release fertilizer carrier.The pyrolysis temperature was the core driving force for regulating the physicochemical characteristics of biochar.Low temperature pyrolysis was beneficial for retaining acidic functional groups,medium temperature pyrolysis could increase the specific surface area and cation exchange capacity of biochar,and high temperature pyrolysis could enhance the long-term stability and alkaline neutralization effect of carbon.Meanwhile,slow heating mode and extended residence time could effectively promote the formation of micropores inside biochar.At the level of soil improvement,the compatibility between the preparation process and the physical and chemical properties of soil directly determined the effectiveness of biochar improvement.Among them,biochar prepared by slow heating at medium temperature had the most significant effect on reducing soil bulk density.Compared with manure based biochar,wood and shell biochar had a better effect on increasing the effective water content of sandy soil.Biochar regulated soil biological properties by providing microbial habitat and nutrient supply for soil microorganisms,and its impact on enzyme activity exhibited a feedback mechanism that varied depending on the enzyme.In the future,the focus should be on the construction of big data prediction models for process-characteristics-function,analysis of the long-term evolution of soil-crop systems and their micro ecological mechanisms,as well as the creation of customized biochar based new products for specific scenarios.