1. Mixed Oak Ecosystem: Field and Lab Data Integration Deborah Hudleston Catherine Resler Mary Walton Chris Weber

2. Review of Field Data Mixed Oak Site 1 (Deborah) Site 2 (Chris) Site 3 (Mary) Site 4 (Cat) Total BA51.4746.5624.2849.80 Lab Soil Texture Analysis Loam Soil Profile Site 1Site 3Site 2Site 4 Oi/Oe1-02-0 1-0 A0-60-50-80-11 E6-275-138-4311-24 Bt5-5213-2743-6324-56 B51-6827-35N/A C68+35+63+56+

3. Soil Texture  Loam textured soil was found at all Mixed Oak sites sampled.  Mixed oak has a greater amount of clay compared to the other three sites sampled.  > amount of rich clay minerals fosters higher NPP.

4. Available Water Content  Decrease in Pore Size= Greater AWC  Mixed Oak has a greater amount of clay than sand compared to the other three sites sampled, therefore a higher AWC.

5. Bulk Density  Well-structured soils have > amounts of macropores -> a higher water-holding capacity than less developed soils.  Mixed Oak had a larger bulk density than the other three sites sampled.

6. Chemical Properties DebChrisMaryCatMean pH H 2 O5.806.126.085.885.97 pH CaCl 2 5.535.615.555.405.52 OM(%)4.273.474.323.713.94 Total Acidity [cmol(+)/kg]0.12 0.060.130.11 CEC [cmol(+)/kg]9.887.788.738.448.71 Base Saturation (%)98.7098.0099.2998.5098.62

7. MO Chemical Properties  pH Calcium rich parent material Buffer to weathering  Organic Matter Oak/maple leaves; moderate A Horizon Large above ground biomass- rapid decomposition  CEC/ Base Saturation Large CEC 98% base saturation Lots of nutrients for plants Consistent with soil type

8.  Largest biomass pool of the Mixed Oak ecosystem is aboveground  Largest pool of N in Mixed Oak ecosystem is in the belowground pool  Highest Aboveground Biomass of all ecosystems studied  Large Discrepancy between aboveground biomass and forest floor biomass - rapid decomposition Nutrient Pools

9.  Net N mineralization is highest in the MO ecosystem - high-lignin litter of the oak trees provide a poor quality substrate to microbial decomposers.  Microbes receive little energy from the lignified litter, supporting little microbial growth, and resulting in low microbial N sink, making the N available to plants. Nitrogen Mineralization

10. Microbial respiration is low – indicating low microbial activity Specific respiration is low - each individual decomposes a relatively small amount of C for the N produced The ratio of C respired to N mineralized is one of the smallest of the 4 ecosystems - this is a further indication of the poor quality of the oak leaf litter as substrate for decomposers. Microbial Biomass and Respiration

11. High Aboveground Biomass Substantial High-Lignin Litter Production Poor Quality Substrate for Microbial Decomposers High N mineralization High Plant Available N Biological Property Connections

12. Summary Physiography Climate Soil Development (Clay = High bulk density and AWC) High CEC and base saturation = High nutrients High N mineralization High biomass NUTRIENT RICH SITE WELL DEVELOPED SOIL

13. MO is a Highly Productive System