Soil Warming Accelerates Biogeochemical Silica Cycling in a Temperate Forest

Frontiers in Plant Science

卷:10

Jonathan Gewirtzman¹  Andrew C. Kurtz²  Robinson W. Fulweiler²  Joanna C. Carey³  Jerry M. Melillo⁵  Jianwu Tang⁵  William J. Werner⁵ 

[1] Department of Biology, Boston University, Boston, MA, United States;

[2] Department of Earth and Environment, Boston University, Boston, MA, United States;

[3] Division of Math and Science, Babson College, Babson Park, MA, United States;

[4] Institute at Brown for Environment and Society, Brown University, Providence, RI, United States;

[5] The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, United States;

关键词: silica;    climate change;    soil;    warming;    phytoliths;    plants;   

DOI  :  10.3389/fpls.2019.01097

来源: DOAJ

【 摘 要 】

Biological cycling of silica plays an important role in terrestrial primary production. Soil warming stemming from climate change can alter the cycling of elements, such as carbon and nitrogen, in forested ecosystems. However, the effects of soil warming on the biogeochemical cycle of silica in forested ecosystems remain unexplored. Here we examine long-term forest silica cycling under ambient and warmed conditions over a 15-year period of experimental soil warming at Harvard Forest (Petersham, MA). Specifically, we measured silica concentrations in organic and mineral soils, and in the foliage and litter of two dominant species (Acer rubrum and Quercus rubra), in a large (30 × 30 m) heated plot and an adjacent control plot (30 × 30 m). In 2016, we also examined effects of heating on dissolved silica in the soil solution, and conducted a litter decomposition experiment using four tree species (Acer rubrum, Quercus rubra, Betula lenta, Tsuga canadensis) to examine effects of warming on the release of biogenic silica (BSi) from plants to soils. We find that tree foliage maintained constant silica concentrations in the control and warmed plots, which, coupled with productivity enhancements under warming, led to an increase in total plant silica uptake. We also find that warming drove an acceleration in the release of silica from decaying litter in three of the four species we examined, and a substantial increase in the silica dissolved in soil solution. However, we observe no changes in soil BSi stocks with warming. Together, our data indicate that warming increases the magnitude of silica uptake by vegetation and accelerates the internal cycling of silica in in temperate forests, with possible, and yet unresolved, effects on the delivery of silica from terrestrial to marine systems.

【 授权许可】

Unknown