Abstract: In recent years, biochar has become a research hotspot in agriculture, ecological remediation and environmental protection. It is generally believed that biochar can improve the soil quality, increase soil carbon sequestration, reduce atmospheric CO₂ concentrations, and remediate the polluted environment. After a large amount of utilization, biochar may change the property of soils and affect environmental behaviors and fate of heavy metals and organic pollutants in soil. In this review, the effects of biochar on adsorptiondesorption, species transformation, and migration behaviors of heavy metals in soilplant systems, as well as on adsorption, volatilization, other environmental behaviors and bioavailability of organic pollutants were summarized. Accordingly, some current problems such as environmental risks of biochar application were analyzed, and future research directions were prospected in terms of transformation and fate, long-term environmental effects and application direction of biochar.

Key words: landscape pattern, land use intensity, spatial evolution, Guizhou., basin