Abstract:A better understanding on the effect of biochar derived from different straw types on soil infiltration and evaporation is of great significance for resource utilization of agricultural straw waste and efficient use of soil and water resources. In the present study, by using the soil column simulation investigation, biochars derived from three straw materials (oilseed rape stalk, quinoa stalk, and potato stalk) were used to explore the effect of biochar from different raw materials on soil wetting process, the cumulative infiltration amount and evaporation. The results showed that biochars derived from different feedstocks had significant effect on soil infiltration and evaporation. Biochar derived from potato stalk accelerated significantly the advancement of wetting front, while the ones derived from oilseed rape stalk, quinoa stalk slowed down the mid-late wetting process. Overall, biochar addition improved early soil infiltration rate and decreased stable infiltration rate in late period. Among the three tested biochars, the one derived from potato stalk performed the best in improving soil infiltration, with the cumulative infiltration 67.8 mm after 55 minutes, which was 41.8% higher than control treatment without biochar addition. The Kostiakov model performed best in simulating soil infiltration with biochar addition. Biochar addition had no significant effect on early soil evaporation, but increased significantly the later soil evaporation rate. After the successive evaporation of 30 days, the cumulative evaporation rates with biochar addition derived from potato stalk, oilseed rape stalk, and quinoa stalk were 5.2%, 9.2% and 10.2% respectively higher than CK. Our results suggest that biochar derived from potato stalk could improve soil infiltration ability, which provides scientific basis for choosing reasonable biochar raw materials in the eastern Qinghai Province.