Differential soil fungus accumulation and density dependence of trees in a subtropical forest

Fungal influence on density dependence Tree species in highly diverse tropical forests tend to exhibit conspecific negative density dependence, a phenomenon whereby individuals of the same species tend to grow at a distance from one another. This is understood to be a key driver of species coexistence. The strength of negative density dependence varies between species, but the mechanisms driving this variation are unknown. Chen et al. studied tree species in a subtropical forest in China and found an important role for soil-dwelling fungi in this variation. Elevated accumulation of pathogenic fungi leads to stronger negative density dependence, whereas elevated accumulation of mutualistic fungi leads to weaker negative density dependence. Science , this issue p. 124