Long-term intensive management increased carbon occluded in phytolith (PhytOC) in bamboo forest soils

Carbon (C) occluded in phytolith (PhytOC) is highly stable at millennium scale and its accumulation in soils can help increase long-term C sequestration. Here, we report that soil PhytOC storage significantly increased with increasing duration under intensive management (mulching and fertilization) in Lei bamboo (Phyllostachys praecox) plantations. The PhytOC storage in 0-40 cm soil layer in bamboo plantations increased by 217 Mg C ha(-1), 20 years after being converted from paddy fields. The PhytOC accumulated at 79 kg C ha(-1) yr(-1), a rate far exceeding the global mean long-term soil C accumulation rate of 24 kg C ha(-1) yr(-1) reported in the literature. Approximately 86% of the increased PhytOC came from the large amount of mulch applied. Our data clearly demonstrate the decadal scale management effect on PhytOC accumulation, suggesting that heavy mulching is a potential method for increasing long-term organic C storage in soils for mitigating global climate change.