PhytOC in plant ecological system and its important roles in the global soil carbon sink.

Abstract

As a substantial component of soil organic carbon occluded within phytoliths，PhytOC is a result of biomineralization within plants and highly resistant to decomposition in the soil environment. PhytOC accumulation rates have contributed about 15.0%-37.0% to the estimated global mean long-term soil carbon accumulation rate which is 2.4 gm-2a-1 over the last 10 000 years. There are ways to enhance both short and long-term carbon sequestration by cultivation of high PhytOC-yielding plant species of agricultural crops. Most of the economically important agricultural plant species such as barley，maize，rice，sorghum，sugarcane and wheat, are producers of phytoliths. It was estimated that the above-mentioned crops globally produced PhytOC of （5.08-12.01）106 ta-1. The paper reviewed the formation mechanism，characteristics and accumulation rate of PhytOC in the plant ecological system，the agronomy measures to improve the accumulation rate and its important role in the global soil carbon sink. ［Ch，56 ref.］