One of the major human impacts on grassland ecosystems, is the the application of fertilizers and the alteration of grazer-plant interactions.
Nash's Field Experiment, situated in Silwood Park, manipulates grassland to investigate how nutrient availability and grazing alters plant species composition and productivity.
The experiment is a factorial split-plot design, replicated in two blocks of 22 x 44 m plots. The experimental plots receive a combination of treatments: the application of nutrients (N, K, P, Mg) in different combinations, the exclusion of herbivores including rabbits and molluscs, the manipulation of soil pH through periodic applications of lime, and the application of selective herbicides.
Initiated by Professor Mick Crawley, treatments have been applied to all plots continuously since 1992. Data has been collected relating to the standing biomass or percentage coverage of each plant species present in all plots .
This experiment has been supported by the Department of Life Sciences at Imperial College London and more recently by NERC grants to Dr. Thomas Bell.