Dr. Brian Brassard and colleagues have a paper in the Journal in vol 101:1 titled Tree species diversity increases fine root productivity through increased soil volume filling. Read the paper here.
The authors have provided a short synopsis of the paper and a nice photo.
The small fine roots of plants are responsible for taking up nutrients and water from the soil and their production account for a major share of the production of terrestrial ecosystems. While diversity effects on ecosystem function have been extensively studied for the aboveground component of terrestrial ecosystems, diversity effects on fine root productivity and their mechanisms remain unclear. In our current paper, we investigated the effects of tree species diversity on fine root productivity and soil volume filling of mature, naturally established boreal forests. We found that fine root production increased with tree species evenness. Higher fine root productivity in evenly mixed- than single-species dominated stands was realized by filling more soil volume horizontally and vertically, driven by differences in inherent phylogenetic and/or functional traits among the mixtures’ component species. Our results provide some of the first direct evidence that tree species diversity can achieve higher productivity belowground by using site resources more completely. Our results indicate managing forest tree diversity will be an effective means to improve ecosystem function in natural environments.