Potential use of biochar as a soil amendment to sorb terbuthylazine and 2-methyl-4-chlorophenoxyacetic acid

Protecting natural water resources is al the farefront af agroecosystem sustainability. The intensification of agricultural activity ineludes using pesticides for crop protection, but pesticides also have associated potential environmental risks. Pesticides can contaminate soils, and pesticide runoff and leaching can impact surface and groundwater quality. Terbuthylazine and 2-methyl-4-chlorophenoxyacetic acid (MCPA) are common herbicides used in olive agroecosystems in Southern Spain. Both terbuthylazine and MCPA are mobile and have a high risk as a water contaminate. Developing low-cost, effective adsorbents that sequester surp lus applied pesticides not utilized by the target may reduce the potential contamination risk. Biochars, carbon-rich materials created by heating biomass in a lowoxygen environment have been shown to have a high capacity to sorb organic compounds. In this work, the terbuthylazine and MCPA sorption properties of a biochar sourced from agricultural, garden, and sustainable forestry wastes are investigated. Sorption results and cost efficiency will be discussed. Biochar sourced from agricultural waste can be a low-cost sustainable strategy to reduce pesticide leaching and runoff, decreasing the risk of groundwater and surface water contamination.