Silicon Affects Plant Stoichiometry and Accumulation of C, N, and P in Grasslands

Frontiers in Plant Science

Fan Ding¹  Hongyan Liu²  Changxun Yu³  Guozheng Hu⁴  Zhaoliang Song⁵  Qian Hao⁵  Shilei Yang⁵  Zichuan Li⁶ 

[1] College of Land and Environment, Shenyang Agriculture University, Shenyang, China;College of Urban and Environmental Sciences, Peking University, Peking, China;Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden;Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China;Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China;Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, China;

关键词: carbon cycles;    grasslands;    silicon;    nutrient utilization;    stoichiometry;    P deficiency;   

DOI  :  10.3389/fpls.2020.01304

来源: DOAJ

【 摘 要 】

Silicon (Si) plays an important role in improving soil nutrient availability and plant carbon (C) accumulation and may therefore impact the biogeochemical cycles of C, nitrogen (N), and phosphorus (P) in terrestrial ecosystems profoundly. However, research on this process in grassland ecosystems is scarce, despite the fact that these ecosystems are one of the most significant accumulators of biogenic Si (BSi). In this study, we collected the aboveground parts of four widespread grasses and soil profile samples in northern China and assessed the correlations between Si concentrations and stoichiometry and accumulation of C, N, and P in grasses at the landscape scale. Our results showed that Si concentrations in plants were significantly negatively correlated (p < 0.01) with associated C concentrations. There was no significant correlation between Si and N concentrations. It is worth noting that since the Si concentration increased, the P concentration increased from less than 0.10% to more than 0.20% and therefore C:P and N:P ratios decreased concomitantly. Besides, the soil noncrystalline Si played more important role in C, N, and P accumulation than other environmental factors (e.g., MAT, MAP, and altitude). These findings indicate that Si may facilitate grasses in adjusting the utilization of nutrients (C, N, and P) and may particularly alleviate P deficiency in grasslands. We conclude that Si positively alters the concentrations and accumulation of C, N, and P likely resulting in the variation of ecological stoichiometry in both vegetation and litter decomposition in soils. This study further suggests that the physiological function of Si is an important but overlooked factor in influencing biogeochemical cycles of C and P in grassland ecosystems.

【 授权许可】

Unknown