AbstractThe present study was conducted at SKUAST-K Shalimar during 2021-2022 to evaluate the effect of biochar amendments on soil microbiological properties under heavy metal contamination (Cd, Pb, and Cu). Pots were filled with soil spiked with heavy metals at double the threshold levels (5.2 ppm Cd, 100 ppm Pb, and 200 ppm Cu) and treated with biochar at rates of 0%, 1%, 3%, 5%, and 10% (w/w). Biochar was prepared through pyrolysis at 550°C using dal weed, deodar needles, and apple leaves. Spinach (Spinacia oleracea) was grown under these conditions, and soil microbial properties were analyzed post-harvest. Results indicated a significant improvement in the total microbial count (CFU/g) with biochar application. The pooled mean bacterial counts ranged from 4.466 × 107 CFU/g (T1 i.e., control with no biochar) to 14.50 × 107 CFU/g (T5: 10% biochar from dal weed), with dal weed biochar showing superior enhancement. Similarly, the pooled mean fungal counts varied between 1.60 × 105 CFU/g (T1) and 4.65 × 105 CFU/g (T5). Higher biochar concentrations and dal weed based biochar consistently enhanced microbial proliferation compared to control and other treatments.
Azad et al. (Wed,) studied this question.