In‐situ biochar production associated with paddies: Direct involvement of farmers in greenhouse gases reduction policies besides increasing nutrients availability and rice production
Mohammad Ghorbani, Elnaz Amirahmadi, Kazem Zamanian
Abstract
Abstract Treating soils with pyrolyzed biomass, that is biochar, is proposed as a conditioner and a carbon geoengineering measure. Rice is known as a strategic crop and rice husk is a cheap and available feedstock material for biochar in particular in Asia. We conducted a field experiment with laboratory biochar (LB) and locally produced [in‐situ biochar (IB)] applied at rates of 10 and 20 t ha −1 using a randomized block design in three replicates to examine the efficiency of IB for improving soil condition for rice production, and to propose a cheap and in‐farm applicable measure to decrease greenhouse gases (GHGs) emissions from the agricultural sector. Grain yield significantly increased following biochar addition by 52.2%, 53.2%, 65.4%, and 67.2% in LB10, IB10, LB20, and IB20, respectively. Total biomass in all biochar treatments had a significant difference ( p < 0.05) compared with our control and the highest biomass belonged to LB20 and IB20 with 12.2 and 15.7 t ha 1 , respectively. The highest grain nitrogen, phosphorus, and potassium was in IB20. Compared to the control, IB20 significantly decreased emissions of CH 4 by 72.3%, N 2 O by 85.8%, and CO 2 by 32.9%. IB is as effective as LB. IB production and application provide a sustainable management approach for dealing with crop residues, improves soil conditions (aeration and nutrients availability) for crop growth, and directly and in a practical way involves farmers in GHGs reduction policies.