A field study was conducted at research farm of Arid Agriculture University Rawalpindi, to find the relation between biochar application rates and days after its application on soil pH, EC, TOC, Nitrate-Nitrogen, extractable phosphorus and available potassium. Samples were taken from 0-15 cm depth at 0 days, 60 days, and 120 days of biochar application. Biochar were made from wheat straw and sugarcane bagasse, and applied at the rate of 5 and 10 t/ha of both type. Results showed no significant change in soil pH, Nitrate, and Nitrogen. While soil electrical conductivity, total organic carbon, phosphorus and potassium showed significant increase. Soil EC increased by 24% in treatment sugarcane bagasse at 10 t/ha after 120 days of its application. 36% increase was observed in total organic carbon in soil treated with sugarcane bagasse biochar at 10 t/ha after 60 days of its application. Soils treated with 10 t/ha wheat straw biochar and sugarcane bagasse biochar showed 27% and 26% increase in extractable phosphorus respectively after 60 days of its application. Biochar (wheat straw) applied at 10 t/ha elevated soil extractable potassium 10.7% after 120 days of its application and 10.3% increase was observed after 60 days of its application.
