Carbon Transformations of Biochar Based Co-Composting - A Review

Abstract

Abstract:: Biochar-Amended Composting (BAC) plays an integral role in sustainable agricultural practices due to its multiple benefits in crop production, soil nutrient retention, carbon sequestration and environmental protection. Although accepted as a traditional method, there is lack of understanding in defining its suitability and efficiency on various base-materials and conditions. Being two carbon-based entities with plentiful nutrients and surface activity, biochar and compost find application in agricultural fields together or separately for improving the soil properties and crop productivity. Recent studies focus on defining the optimum conditions for their preparation, mixing, application and monitoring under various feed, soil, crop and climatic conditions. However, due to the complexity and specificity of the system, many influencing aspects of their interaction are yet unknown in detail. In this review, we analyze the recent advancements in the selection and preparation of new materials for BAC, and explain the mechanisms of Organic Matter (OM) degradation/sequestration happening in soil based on possible chemical/morphological transformations of organic carbon. Most of the performance results are in agreement with the previous records, but a few contradictions observed under diverse experimental conditions. In general, BAC enhanced the mineralization of carbon and sequestration of heavy metals, and stabilized labile fraction of OM due to the development of carbonyl, phenolic and aromatic functional groups on its surface. In addition, aging of biochar resulted in stable N-C=O and amino groups for the adsorption of nitrogen compounds thus decreasing the potential greenhouse gas emissions. The study further identifies potential future research gaps in this area.

Organic residues and their impact on soil health, crop production and sustainable agriculture: A review including bibliographic analysis

“…This combination compost is generally preferred over the use of biochar alone because of direct implications on the surface modification of biochar. This leads to improved nutrient recovery, slow release of toxins and reduced GHG emissions when applied to soil (Pandiyan et al, 2021). COMBI can also be used to remediate soil that is contaminated with potentially toxic metals (Chen et al, 2020; Luo et al, 2017; Rodríguez‐Vila et al, 2016; Teodoro et al, 2020; Ye et al, 2019).…”

Atmospheric Emissions of Volatile Organic Compounds from a Mine Soil Treated with Sewage Sludge and Tomato Plants (Lycopersicum esculentum L.)

“…Amendment addition enhances soil OC, which is the main controlling factor of the adsorption of BTEX and other neutral hydrophobic pollutants (Zytner 1994;Takaki et al 2014). For instance, an inhibition of greenhouse gas emissions, such as CO 2 , N 2 O, methane or ammonia, after sewage sludge amendment has been reported (Awasthi et al 2016;Pandiyan et al 2021). Besides, addition of sewage sludge does not only modify the soil porous micro-structure, which in turn promotes adsorption, but also provides the soil with a source of labile OM, boosting the activity of soil microbes, which contribute to degrade VOCs (Agegnehu et al 2016;Awasthi et al 2020).…”

Biochar can mitigate co-selection and control antibiotic resistant genes (ARGs) in compost and soil

“…Biochar have been reported to enhance the effectiveness of biowastes composting and to improve the quality of the final product ( Chavez-Garcia et al., 2020 ; Godlewska et al., 2017 ; Liu et al., 2017 ; Pandiyan et al., 2021 ; Teodoro et al., 2020 ; Wang and Zeng, 2018 ; Wu et al., 2017b ; Xiao et al., 2017 ; Yin et al., 2021 ; Zhang et al., 2021c ). Biochar has been shown in literature to reduce gaseous emissions ( Awasthi et al., 2017 , 2020a ), reduce N and C losses ( Awasthi et al., 2020b ; Zhang et al., 2021a ), reduce composting duration ( Qu et al., 2020 ), increase humification ( Vandecasteele et al., 2014 ; Jindo et al., 2016 ), improve aeration and porosity ( Zhang et al., 2014 ), reduce bioavailable HMs fraction ( Cui et al., 2020b ), reduce ARGs ( Qian et al., 2019 ; Cui et al., 2016a , 2016b ), improve microbial activity ( Awasthi et al., 2020b ; Lia et al., 2020 ; Qu et al., 2020 ), improve available nutrient ( Zainudin et al., 2020 ; Wei et al., 2021 ), and reduce ecotoxicity in compost ( Wang et al., 2017 ).…”

“…Biochar is used in improving physicochemical and microbiological properties of soil ( Guo et al., 2021 ; Kaur and Sharma, 2021 ) and compost ( Akdeniz, 2019 ; Pandiyan et al., 2021 ; Yin et al., 2021 ). It is also used to remove contaminants (including antibiotics) from aqueous solutions and environmental media ( Chen et al., 2021 ; Cheng et al., 2021 ).…”