Contents lists available at ScienceDirect Journal of Environmental Management journal homepage: www.elsevier.com/locate/jenvman Research article Thermophilic ligno-cellulolytic fungi: The future of efficient and rapid bio- waste management Asha Sahu a,* , M.C. Manna a , Sudeshna Bhattacharjya a , J.K. Thakur a , A. Mandal a , Mohammad Mahmudur Rahman b , U.B. Singh c , V.K. Bhargav d , S. Srivastava a , A.K. Patra a , S.K. Chaudhari e , S.S. Khanna f a ICAR- Indian Institute of Soil Science, Bhopal, 462038, India b Global Centre for Environmental Remediation (GCER), Faculty of Science, The University of Newcastle, Callaghan NSW 2308, Australia c ICAR- National Bureau of Agriculturally Important Microorganisms, Mau Nath Bhanjan, 275103, India d ICAR- Central Institute of Agricultural Engineering, Bhopal, 462038, India e Assistant Director General (S&WM, NRM), ICAR, New Delhi, 110001, India f Former Member, Planning Commission, Government of India, New Delhi, 110001, India ARTICLE INFO Keywords: Composting Ligno-cellulolytic Thermophilic Maturity indices Stability indices Crop residues ABSTRACT To accelerate the process of decomposition using consortia of thermophilic ligno-cellulolytic fungi, different crop residues viz. sorghum (SG), soybean (SS), maize (MS), sugarcane (SC), cotton (CS) and pigeon pea (PS) with a varied C:N ratio and sawdust (SD) having high lignin content were collected and used for decomposition process. Compost quality assessed by evaluating different maturity and stability indices at five succeeding stages [first mesophilic (M1), thermophilic (T), second mesophilic (M2), cooling (C) and humification (H)]. A significant reduction was observed in the C:N ratio, biodegradability index, nitrification index, ratio of water-soluble carbon to organic nitrogen (WSC/Org.N) with an increase in concomitant over time while Ash (%), organic matter loss (%), CEC/TOC ratio, cellulose biodegradation ratio (BR) and lignin/cellulose ratio were significantly increased with time. By correlation study, biodegradability index (BI) and fluorescein diacetate (FDA) hydrolysis emerged as the most suitable compost maturity and stability parameters, respectively. Principal component analysis (PCA) results confirmed that BI, BR, WSC/Org. N and FDA can be regarded as key indicators for assessing compost quality. Our findings conclude that fungal consortia of Tricoderma viride, Rhizomucor pusillus, Aspergillus awamori and Aspergillus flavus can accelerate decomposition time from 8 to 12 months (which is normal farming practice) to 120 days. 1. Introduction World's most important zones devoted to intensive agriculture are located in sub-tropical climates that produce several million tonnes (Mt) of crop residues annually. These residues either burnt or removed from agricultural fields due to scarcity of time, space and manpower. The result is a substantial decline in productivity, soil organic carbon, soil health, and indirect loss of biodiversity, human health problems and climate change. It is estimated that burning of 98.4 Mt of crop re- sidue emits 8.57 Mt CO, 141.15 Mt CO 2 , 0.037 Mt SO x , 0.23 Mt NO x , 0.12 Mt NH 3 (Jain et al., 2014). In the past few decades, strategies have been adopted for managing the huge amounts of crop residues and these methods include residue incorporation, conservation agriculture, off-farm composting, etc. However, the pace of residue generation is making it challenging to manage it scientifically and effectively. Thus, more emphasis has been given to residue recycling back into the soil because it can stabilize organic matter, reduce environmental pollution and serve as a potential source of soil humus and humic substances (Manna et al., 2018). Surface retention and composting are promising on-farm management options to address the issue of burning as well as maintaining soil health and long-term sustainability of crop pro- ductivity. In general, farmer's practice takes 8–12 months for making compost. Thus, there is an urgent need to produce compost in a shortest possible time that may minimize burning of residues. A few studies have at- tempted to assess compost quality in terms of stability and maturity. Compost maturity refers to its efficiency for plant growth, whereas stability points to the degree or rate of organic matter decomposition https://doi.org/10.1016/j.jenvman.2019.04.015 Received 10 October 2018; Received in revised form 23 February 2019; Accepted 6 April 2019 * Corresponding author. Division of Soil Biology, ICAR- Indian Institute of Soil Science, Bhopal-462038, India. E-mail address: ashaars.iiss@gmail.com (A. Sahu). Journal of Environmental Management 244 (2019) 144–153 0301-4797/ © 2019 Elsevier Ltd. All rights reserved. T