The influence of nutrient availability on plant production and on above- and belowground diversity across grasslands worldwide.

Herbaceous Diversity Network (HerbDivNet, including 30 grassland sites distributed across 19 countries and 6 continents) recently demonstrated that grassland plant diversity peaks at intermediate productivity. While climate was accounted for in their analyses of the relationship between plant diversity and productivity, as usual, belowground factors such as nutrient availability and microbial diversity were not. However, nutrient availability is a crucial determinant of plant productivity and plant species composition and diversity. Microbial diversity is a key unknown link here as it is strongly driven by nutrient availability and plant diversity, but microbes too can feed-back to both by determining nutrient cycling and by acting as symbionts or parasites on plants. This study aims to evaluate to what extent different soil factors that determine nutrient availability, in combination with climate can explain plant biomass production, species diversity (plant and soil microbial diversity), and the relationship between these within and across the HerbDivNet sites. To this end, soil samples from HerbDivNet sites will be analyzed for nutrient availability and microbial diversity to determine: (1) how nutrient availability influences grassland productivity, diversity and their relationship, (2) how nutrient availability influences microbial diversity and (3) whether these factors can be integrated to better understand above- and belowground diversity patterns in grasslands worldwide.

Keywords:ECOSYSTEMS, GRASSLANDS

Disciplines:Plant biology, Terrestrial ecology