Biological conversion of low-grade coal discard to a humic substance-enriched soil-like material  

作　　者：Lerato Mary Sekhohola Ashton Keith Cowan 

机构地区：[1]Institute for Environmental Biotechnology, RhodesUniversity (EBRU), P.O. Box 94, Graharnstown 6140, SouthAfrica

出　　处：《International Journal of Coal Science & Technology》2017年第2期183-190,共8页国际煤炭科学技术学报（英文）

摘　　要：A mutualistic relationship between grasses, coal-degrading fungi, and arbuscular mycorrhizal fungi was pro- posed to account for the phyto-biodegradation of coal discard. In this study pot trial experiments were carried out to confirm transformation of the carbonaceous substrate, in the presence of a suite of coal degrading fungi and arbuscular mycorrhizal fungi, into a humic-enriched soil-like material in the Cynodon dactylon/coal rhizosphere. The results show that after 47 weeks of C. dactylon growth on coal discard the concentration of humics increased from （62.9 -4- 1.5） to （112.1 ＋ 5.4） mg/kg. Substrate humic acid-like substance concentration positively correlated （r2 = 0.95） with accumu- lation of above ground C. dactylon biomass. FTIR spectroscopy of the extracted humic-like substances confirmed both product identity and increased oxidation of the coal discard substrate. Substrate ash content and electrical conductivity declined coincident with an increase in humic acid-like substance concentration, which together reduced the intensity of acidity in the C. dactylon/coal discard rhizosphere. These observations support the proposal that biological oxidative degradation of coal discard leads to increased humic-like substance concentration and formation of a soil-like material. Results have profound implications for use of coal discard as an organic substrate to replace topsoil in phyto-bioreme- diation strategies for sustainable large-scale rehabilitation of coal discard dumps.

关 键 词：BIODEGRADATION Cynodon dactylon Humic acid-like substances Neosartorya fischeri Coal discard 

分 类 号：TD[矿业工程]