effects of bagasse and its biochar on the leaching of solutes and water uptake by field pea (pisum sativum l.) under controlled and free drainage conditions and irrigation with municipal wastewater

This study examined the effects of sugarcane bagasse and its biochar on soil properties, field pea (pisum sativum l.) yield, and nutrient absorption under different drainage conditions using municipal wastewater for irrigation. the experiment was conducted as a factorial design with two factors in a greenhouse. the first factor was drainage condition at two levels: controlled drainage (cd) and free drainage (fd). the second factor was the application of sugarcane bagasse and its biochar at four levels: 1% bagasse (ba1), 2% bagasse (ba2), 0.66% biochar (bic0.66), and 1.32% biochar (bic1.32). municipal wastewater was used for irrigation throughout the study. results showed that adding sugarcane bagasse and its biochar improved soil physical properties, particularly water holding capacity, with bic1.32% being the most effective. in cd treatments, capillary rise provided additional water and nutrients, increasing irrigation water productivity for field pea by 1.8 times compared to fd. the controlled drainage also reduced water consumption by 22% and enhanced nitrate and phosphate absorption by 44.25% and 28.78%, respectively. however, it decreased nitrate leaching, phosphate leaching, and drainage water volume by 19.73%, 24.23%, and 31.23%, respectively. additionally, nitrate and phosphate uptake by field pea increased by 75% and 13.3% under cd compared to fd. the interaction between additives and drainage treatments significantly affected plant weight, with the highest yield observed in the cd and bic1.32% treatments. overall, cd combined with bic1.32%, bic0.66%, ba1%, and ba2% increased plant dry weight by 26.2%, 13.2%, 25.8%, and 26%, respectively, compared to fd. these findings highlight the potential of sugarcane bagasse and biochar for enhancing soil quality, improving water-use efficiency, and boosting crop yields under various drainage conditions.