1. A glimpse below… The soil food web Teri C. Balser, Assistant Professor, UW-Madison tcbalser@wisc.edu

2. What is soil biology? What role does it play in soil quality?

3. Soil organisms are involved in nearly every aspect of soil quality Organic matter Nitrate Leaching Soil Community Nutrient cycling Structure/Aggregation Humification Decomposition

4. In order to understand how biology affects our soils - we need to understand a little about the organisms who live there

5. Water Soil particles Plant roots Soil is a habitat

6. Soil is alive… For example, in 1g of soil: >100,000,000 bacterial cells >11,000 species of bacteria Also fungi and larger animals

7. Who’s there? Macrofauna: Soil ‘Engineers’

8. TermiteSnail Earthworm Vole Soil Animals Centipede Pseudoscorpion

9. 1.Decomposition (shredding residues) 2.Mixing soil (aeration) Decomposition rate of blue grama (Bouteloua gracilis) Soil animals are important for

10. Who’s there? Mesofauna: Soil predators, pathogens, herbivores

11. Soil mesofauna Nematodes Mites Protozoa

12. Soil mesofauna Nematodes Mites Protozoa Soil mesofauna are important for 1.Residue decomposition 1.Predation 1.Pathogenesis

13. Microorganisms: Soil process controllers

14. Soil microorganisms Fungi Bacteria

15. Filamentous growth What are the advantages of filamentous habit?

16. Fungi Filamentous growth Functionally critical! -Wood degrading -Mycorrhizal association myco (fungus) + rhiza (root) (Symbiotic structure formed by a fungus plus a plant)

17. Source: Harrison et al 1999 Roots without mycorrhizae

18. Source: Harrison et al 1999 Roots with mycorrhizae

19. Bacteria Small, single celled ~2µm What is the importance of small size?

21. Bacteria Small, single celled Abundant Bacteria Fungi Conventionaltillage No-till Prairie Forest

22. Bacteria Small, single celled Abundant Diverse - taxonomically and functionally!

23. Diversity in soil is important for nitrogen cycling.

24. Relationship to soil quality?

25. Diversity may be important in response to management

26. Ecosystem Microbiology Laboratory, UW-Madison (www.ecosystem-microbiology.wisc.edu) Teri C. Balser tcbalser@wisc.edu USDA-CREES, NSF, Andrew W. Mellon Foundation, NASA Lab members: Jessica Mentzer, Jenny Kao, Liang Chao, Nicole Craig, Lindsey Moritz, Meredith Schuman, Dr. David Bart, Dr. Daouda Ndaiye, Dr. Harry Read THANK YOU!