Carbon mineralization in subtropical alluvial arable soils amended with sugarcane bagasse and rice husk biochars

Subtropical recent alluvial soils are low in organic carbon (C). Thus, increasing C is a major challenge to sustain soil fertility. Biochar amendment could be an option as biochar C-rich pyrolyzed material, which slowly decomposed soil. We investigated mineralization (CO2-C evolution) two types of (recent and old soils) amended with feedstocks (sugarcane bagasse rice husk) (1%, weight/weight), well their biochars aged under controlled environment (25 ± 2 °C) over 85 d. For the (charland soil), highest absolute cumulative CO2-C evolution was observed sugarcane treatment (1 140 mg kg-1 soil) followed by husk 090 soil); lowest amount (150 treatment. Similarly, for (farmland 290 then 270 (200 Aged treatments reduced 10% 36%, respectively, compared unamended soil, 18%, Both normalized were similar between treatments, treatments. In both soils, feedstock resulted evolution, The rate constant stable pool (Ks) lower those had negative priming effect but more prominent These results would have good implications improving matter content C-poor soils.