The Impact of Native Grassland Conversion to Cultured Systems On the Terrestrial Silica Cycle.

The mineralogical components of soils are both directly and indirectly linked to biological activity. A key component of the soils mineralogical composition is Biogenic Silica (BSi) which is derived directly from plants and has been used as a key indicator of past climatic and vegetative history and as a proxy for biological cycling of nutrients in soils.  Because grassland ecosystems are a particularly large reservoir of BSi (due to dominance by grasses with relatively high silica content), we argue that  that udnderstanding the primary controls on soil BSi pools in grass dominated ecosystems is particularly critical to the coupling of terrestrial and aquatic Si cycles, and thus the global Si and C cycles. Because precipitation, fire and land use regimes are being impacted directly and indirectly by human activities in grasslands and savannas worldwide and these activities have potential implications for terrestrial BSi totals and cycling, and thus the future of global grasslands in the presence of a changing climate.