The Nutrient Network 2012 Workshop

1. The Nutrient Network 2012 Workshop Sponsored by NSF,UMN, and Institute on the Environment

2. The Nutrient Network • Conceived in 2006, in part because of the limitations of meta-analysis • 60 sites (48 experimental, 12 observational), 13 countries, 6 continents • Standard NPK fertilization protocol implemented in 2008 (at most sites) • 42 sites have built vertebrate exclusion fences • 3+ papers published; 2 in submission; 20+ more in progress … You are here

3. Creating a predictive framework for a critical global biome 2000 - Reactive nitrogen deposition [mg N/m2/year] • How general is our current understanding of productivity-diversity relationships? • To what extent are plant production and diversity co-limited by multiple nutrients? • Under what conditions do grazers or fertilization control plant biomass, diversity, and composition?

4. The Nutrient Network • Standardized experimental and sampling protocols • Nominal annual time and financial investment for any single site • At all experimental sites: • N,P, K factorial addition • At all fence sites: • 2 Herbivore exclusion fences per block (around N+P+K, and control plots)

5. Vancouver Island, BC Cedar Creek LTER, MN Hanover, NH Andrews LTER, OR Savannah River, SC Sagehen Reserve, CA Sevilleta LTER, NM

6. Mt. Gilboa, South Africa Serengeti, Tanzania Pappenburg, Germany Mustair, Switzerland Kinypanial, Australia Mt. Caroline, Australia

7. new NutNet member sites CEREES – Ecotron IDF (France) Companhia das Lezírias (Portugal)

8. new NutNet member sites Kibber, Spiti Valley (India)

9. new NutNet member sites Pichincha (Ecuador) Mar Chiquita (Argentina)

10. new NutNet member sites Koffler Scientific Reserve at Joker's Hill University of Toronto

13. State of the Nut-work • 50 experimental sites in 14 countries • 44 both experiments, 6 nutrient experiment only • 1830 – 5 x 5 m plots in the network • Information on species identity, cover, biomass, light, soil chemistry from almost all plots • 1,752 taxa, 117 distinct families, 47 orders • (~0.6% of Earth’s estimated vascular plant flora) Azi, China

14. NutNet “active” manuscripts * Nutrients and herbivores control plant diversity and function in a global grassland experiment * Biological invasion in the world’s grasslands A global test of niche destruction and biodiversity loss * What limits productivity in grasslands worldwide? Production and mass loss relationships show regional contingencies within the world’s grasslands Relative importance of deterministic vs. stochastic community assembly increases with increasing productivity Life history constraints in grassland plant species: a growth-defense tradeoff is the norm Diversity and stability - A worldwide test of the insurance hypothesis within herbaceous dominated ecosystem Global variation in nutrient limitation of grassland litter decomposition How do fluctuating resource conditions alter the abundance of introduced Beyond complementarity: multi-factor effects of native richness underlie the invasion paradox What are the effects of fertilization and herbivory on spatial and temporal turnover of species composition? Multivariate control over the global productivity-diversity relationship Nutrient additions and grazing shift plant functional group composition across grasslands worldwide A global experimental examination of ecological contingency in the strength herbivore-mediated biological invasions Strong abiotic controls over seed predation at biogeographic scales Global drivers of loss of biodiversity with eutrophication Impact of atmospheric nitrogen deposition and nitrogen addition on herbaceous vegetation Global predictors of soil organic matter in grassland ecosystems Evolutionary history of vertebrate grazing and plant invasions Effects of primary production and producer diversity on consumer biomass: bottom-up control and compensatory feeding in grassland invertebrate communities Val Mustair, Switzerland

15. NutNet proposed manuscripts Observational Study Does diversity determine resilience of grassland productivity to heat/drought stress? Effects of Plant Invasions on the Richness and Spatial Heterogeneity of Grasslands Ecosystems A global analysis of the relationship between species richness and temporal turnover A global test of the environmental heterogeneity hypothesis of biological invasions Exploring the relationship between the phylogenetic diversity and invasibility of communities at two spatial scales Phylogenetic, functional, and plant trait diversity: Examining potential drivers of primary production in herbaceous systems Multi-Nutrient Experiment Bottom-up Constraints on the Composition of Grassland Arthropod Communities: A Global Comparison Nutrient limitations on biodiversity and primary production between sites of co-varying and decoupled climatic patterns  N and P limitations on N fixing species across a global network of experimental grassland sites (requires foliar analysis)  Organic matter and nutrient export from soils Enemy release and nutrient availability – Biogeographic and community level comparisons How leaky are grassland ecosystems? Fertilization-Exclosure Experiment Positive feedbacks between invasive plants and consumers:  consumer-mediated invasional meltdown of worldwide grassland ecosystems Interactions between plant and microbial communities and nutrient cycling as influenced by grazing and fertilization Global importance of bottom-up versus top-down forces to grassland invertebrate communities Compensation between herbivore guilds in a grassland system Multi-level trophic effects as controlled by grazing and fertilization Do dominant plant species drive community changes in response to alterations in bottom-up and top-down control? Alterations in the reproductive effort of dominant grasses in response to changes in bottom-up and top-down forces Bottom-up and top-down controls of woody encroachment across the North American Great Plains A global study of below-ground allocation patterns in grasslands Val Mustair, Switzerland

16. The task at hand: from ideas/abstracts/drafts & graphs to Manuscripts!