Research progress and forecast of phytolith-occluded organic carbon stability in soil
HE Shanqiong;MENG Cifu;HUANG Zhangting;JIANG Peikun;WU Qifeng;SHEN Jing;School of Environmental and Resource Sciences, Zhejiang A & F University;Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration, Zhejiang A & F University;Agricultural Technology Extension Centre,Lin'an;Shaoxing Station of Agricultural Technique Popularization;
As an important long-term terrestrial carbon fraction, the phytolith-occlu ded organic carbon(Phyt OC) has become an important mechanism in the long-term terrestrial carbon sequestration. The contribution of Phyt OC stability to the global terrestrial soil carbon pool is much greater than Phyt OC stocks. The paper reviewed the formation mechanism and characteristics of Phyt OC, the significance of studying the Phyt OC stability, and the determinants of the Phyt OC stability. Phyt OC produced from different types of vegetations had significantly different stability. Phyt OC produced from the same type of vegetations but under different growth environments also had different stability. The Phyt OC in ancient soil was more stable than that in young soil. The morphological combinations of phytolith in plants were able to respond sensitively to saline-alkali concentrations and p H values in soil. The humidity and precipitation could affect the quantity, size, morphology, assemblages δ~(13)C and δ~(18)O of phytolith. The smaller the Si/Al ratio of phytolith was, the higher the stability would be.