Understanding the ecological mechanisms governing the biogeogoraphy of organisms is essential to predict how climate change will alter ecosystems and their functioning. Factors affecting the patterns of aboveground plant and animal communities across landscapes have received extensive attention in recent decades. In contrast, despite their importance for the functioning of all ecosystems, the processes structuring below ground diversity has received relatively little attention. Moreover, the below ground biogeogoraphy of endangered habitats remains unexplored.
Native tallgrass prairie once dominated large areas of the midwestern United States, but this biome and the soil microbial diversity that once sustained this highly productive system have been almost completely lost, following decades of agricultural practices. Fierer et al. analyzing relict prairie soils, enabling them to reconstruct the soil microbial diversity that once existed in this biome. They found that the biogeographical patterns were largely driven by changes in the relative abundance of one poorly studied bacterial phylum (Verrucomicrobia), that appears to dominate many prairie soils. Metagenomic data suggested that these spatial patterns were associated with strong shifts in carbon dynamics, providing a direct functional consequence of the change in bacterial community composition.
Fierer et al. show that metagenomic techniques can be used to reconstruct below-ground diversity patterns in ancient, or endangered ecosystems. Such information could be used to inform restoration efforts, given the fact that even subtle changes in microbial community composition can have distinct impacts on ecosystem functioning and the global carbon cycle.
Reconstructing the Microbial Diversity and Function of Pre-Agricultural Tallgrass Prairie Soils in the United States by Noah Fierer et al. 2013. Published in Science