1. Predicting diversity of large herbivores from moisture and nutrient availability based on the article of Olff et al. (2002): “Global environmental controls of diversity in large herbivores” John Garcia and Corina Del Fabbro 20.10.2015 1Predicting diversity of large herbivores from moisture and nutrient availability

2. Introduction  Large mammalian herbivores are threatened  Large herbivores require great plant abundance whereas small herbivores require high nutrient content  Rainfall, soil fertility and primary productivity influence plant quality and herbivore community biomass How do rainfall, soil fertility and primary productivity affect herbivore diversity? 20.10.2015 2Predicting diversity of large herbivores from moisture and nutrient availability

3. Outline  Theory and Hypotheses  Model Construction  Model Validation  Predictions on a global scale  Implications  Conclusions Klipspringer (http://www.wildlife-pictures- online.com/image-files/klipspringer_rctb-6638.jpg) 20.10.2015 3Predicting diversity of large herbivores from moisture and nutrient availability

4. Model theory (1)  Plant productivity and quality change across environmental gradients 20.10.2015 4Predicting diversity of large herbivores from moisture and nutrient availability

5. Model theory (2) 20.10.2015 5Predicting diversity of large herbivores from moisture and nutrient availability

6. Model theory (3) 20.10.2015 6Predicting diversity of large herbivores from moisture and nutrient availability

7. Model theory (4) 20.10.2015 7Predicting diversity of large herbivores from moisture and nutrient availability

8. Hypotheses  Increasing moisture → larger herbivores Less moisture + increasing nutrient availability → smaller herbivores  Increasing nutrient availability + intermediate moisture → increasing species diversity 20.10.2015 8Predicting diversity of large herbivores from moisture and nutrient availability

9. Methods  Compilation of occurrence and richness data of all terrestrial species of herbivores (mass > 2 kg)  33 sites in North America and 85 in sub-Saharan Africa  Elaboration of indices for plant-available Moisture and Nutrients  Species Richness is expressed as a proportion of the total species richness per continent (to standardize differences) 20.10.2015 9Predicting diversity of large herbivores from moisture and nutrient availability

10. Model Construction – Species level  Larger species peak at higher moisture levels.  Larger species seem to be independent form plant-available nutrients levels.  Smaller species are more frequent at higher quality plants levels. 20.10.2015 10 Predicting diversity of large herbivores from moisture and nutrient availability

11. Model Construction – Species Richness  Herbivores diversity is higher at sites with intermediate plant-available moisture levels and increases with plant- available nutrients 20.10.2015 11Predicting diversity of large herbivores from moisture and nutrient availability

12. Model Validation  Using the multiple regression model, areas with high diversity of large herbivores were predicted for 10 natural areas in Australia.  Results were compared to observed diversity.  Strong correspondence between predicted and observed areas (R 2 =0.63, p=0.003, n=10). 20.10.2015 12Predicting diversity of large herbivores from moisture and nutrient availability

13. Predictions on a global scale  At global scale predicted regions seem to correspond to areas considered as diverse for this herbivores groups. 20.10.2015 13Predicting diversity of large herbivores from moisture and nutrient availability

14. Implications  25% of the large herbivore species per continental pool can be hosted in less than 5% of land.  Less than 2% of the prime regions for large herbivore diversity overlap with regions designated as biodiversity hotspots.  Current land-use practices suggest that less than 1.2% of the earth's surface might remain to support uniquely diverse, grazing ecosystems by 2025.  The study of these factors could help in spotting potential areas for the conservation of herbivore species. 20.10.2015 14Predicting diversity of large herbivores from moisture and nutrient availability

15. Conclusions  Plant resources (Plant-available moisture and nutrients) constrain the distribution of large herbivores.  Plant-available moisture and nutrients predict patterns of large herbivores diversity  Authors suggest that this approach could be applied to other groups of organisms. 20.10.2015 15Predicting diversity of large herbivores from moisture and nutrient availability