Open AccessGas permeability in soil amended with biochar at different compaction states
Author(s) -
He Huang,
Weiling Cai,
Qian Zheng,
Pei-Nan Chen,
Chun-Rui Huang,
Qiaoying Zeng,
Himanshu Kumar,
HongHu Zhu,
Ankit Garg,
Kulenbekov Zheenbek,
Vinod Kushvaha
Publication year - 2020
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/463/1/012073
Subject(s) - biochar , compaction , water content , soil water , soil science , water retention , environmental science , soil compaction , field capacity , wetting , moisture , porosity , permeability (electromagnetism) , chemistry , geotechnical engineering , materials science , geology , pyrolysis , composite material , biochemistry , organic chemistry , membrane
Biochar amended soil (BAS) is widely studied to apply in green infrastructure, such as landfills and slopes. Presence of biochar improved soil hydraulic properties (e.g. water retention ability) in previous studies, while influence of biochar on gas permeability (k g ) under different compaction states is not clear yet. The main objective of this study is to investigate the k g of BAS under different soil compaction conditions. The soil selected for investigation was poorly graded sand. BAS was compacted in an in-house built 1-D column set up under three different soil density (65 %, 80 % and 95% degree of compaction) were considered in mixtures with 0% and 10% biochar content. The tests were carried out in a greenhouse at Shantou University. In tests, soil column was designed and subjected to drying-wetting cycles, during which soil suction, moisture content and k g were measured. Results showed that BAS (i.e. minimum water content 37.2% and 22.1%) had better water retention performance than bare soil (i.e. minimum water content 20.2% and 19.5%) at compaction conditions (65% and 80% degree of compaction). However, when the degree of compaction increased to 95%, bare soil and BAS shows similar water retention characteristic (i.e. minimum water content 15.7% and 15.9% respectively). The addition of biochar could decrease k g as compared with that of the bare soil, meanwhile, in the lower suction range, k g decreased with an increase of compaction (i.e. k g 65%> k g 80%> k g 95%).