Water Use of Peppers Treated with Biochar and Irrigated with Wastewater
Abstract
Drought is one of the most significant risk factors threatening agricultural production today. Managing soil moisture through the application of biochar and using treated wastewater as an alternative irrigation water source to fresh water are promising approaches to mitigating the effects of drought. This study was conducted in Van province (Türkiye), a semi-arid region, to investigate the effects of varying doses of biochar applications (0, 0.5, 1.5, and 3.0 tons da-1) and different irrigation water qualities (fresh water and treated wastewater) on plant yield, water use potential, and water efficiency of pepper plants (Capsicum annuum L.) using a randomized block design with 3 replications. The results showed that biochar and increasing doses of biochar, and irrigation with treated wastewater compared to fresh water increased pepper yield, decreased irrigation water amount and actual plant water consumption, thus improving water and irrigation water productivity with biochar and treated wastewater. The highest yield increase (16.85%) was obtained at a biochar dose of 3.0 tons da-1. Irrigation with treated wastewater increased yield by 9.75% compared to fresh water and resulted irrigation water saving of approximately 1% on a mean. At a dose of 3.0 tons da-1, biochar application resulted in a mean decrease of 5.21% in irrigation water mount compared to the control. Water and irrigation water productivity increased by 22.42% and 21.26%, respectively, in biochar applications. In irrigation with treated wastewater, water and irrigation water productivity also improved by 10.68% and 10.56%, respectively. In conclusion, applying 3.0 tons da-1 of biochar to the soil and irrigating with treated wastewater in pepper cultivation was found to be recommendable for effective water resource management and sustainable agricultural production under drought conditions. However, further comprehensive studies are needed, and the risks of salinity and heavy metals from treated wastewater should also be considered.