Toward an integrative understanding of soil biodiversity

Soil is one of the most biodiverse habitats on Earth. However, we still lack an integrative conceptual framework for understanding the patterns and mechanisms driving soil biodiversity. This is due to our poor understanding of whether key biodiversity theories (historically developed for aboveground organisms) explain the patterns of soil biodiversity. Here, we present a systematic literature review to investigate how key biodiversity theories (species-energy relationship, theory of island biogeography, metacommunity theory, niche theory and neutral theory) explain observed patterns of soil biodiversity. Then, we discuss spatial compartmentalization of soil into three key parts: soil, soil hotspots and soil microsites, and show how biodiversity theories could be applied at these scales for integrative understanding of soil biodiversity