Heterotrophic Respiration from Nine Nutrient Network Grasslands in North America

This experiment tracks the response of soil heterotrophic respiration (i.e., soil organic matter decomposition), enzyme expression, and microbial biomass in nine US grasslands participating in the globally-distributed Nutrient Network. At Cedar Creek, as in over 70 other sites in grasslands around the world, the experiment aims to describe impacts of increased nutrients (nitrogen, phosphorus, potassium, sulfur and other metals) and decreased herbivory (removal of mammals by fencing). Two overarching questions are being explored with these manipulations: 1. To what extent are plant production and diversity co-limited by multiple nutrients in herbaceous-dominated communities? 2. Under what conditions do grazers or fertilization control plant biomass, diversity, and composition? By utilizing identical protocols at diverse grassland sites around the world, NutNet aims to uncover both the generalities in ecosystem functioning, and the contingencies or differences which can obscure those common mechanisms. In addition to the standard NutNet protocol, e247 includes an additional low Nitrogen gradient (1 gram Nitrogen per meter squared per year and 5 grams Nitrogen per meter squared per year in addition to the standard 10 grams Nitrogen per meter squared per year). These samples in the present dataset were collected at the same time as soil and plant samples for https://doi.org/10.6073/pasta/7f984c2ed9e63754577ee711e6d74a6e.