1. Black Oak- White Oak Forest

2. Manistee National Forest * Outwash plain dominated by Jack Pine to the west * Northern hardwood forest to the east

3. Land Form Kamic Hills Formed by Wisconsin Glaciation approx. 8000-9000 years ago

4. Parent Material Ice contact material Derived from outwash stratified drift laid down by previous Illinoian glaciation (128,000 yrs. ago)

5. Ecosystem overview:

6. Northern Oak Relationships:

7. Soil Profile O e/i/a 2-0 cm; intact and partially decomposed Quercus rubra, Acer rubrum, Q. alba leaves; abrupt smooth boundary. A0-3 cm; black (7.5 YR 2.5/1) loamy sand, weak fine subangular blocky structure; very strongly acid; abrupt smooth boundary. E 3-6 cm; dark gray (7.5YR 4/1) loamy sand; weak medium subangular blocky structure; very strongly acid:, abrupt smooth boundary. B S1 6-14 cm; brown. (7.5YR 4/4) sand; single grain; moderately acid; diffuse smooth boundary. B S2 14-26 cm; strong brown (7.5YR 5/8) sand; single grain; moderately acid; diffuse smooth boundary. C26 cm; dark yellowish brown (10YR 5/8) sand; single grain; moderately acid.

8. Soil Profile

9. Soil Texture Group% sand% silt% clayIn labIn situ Fine Young Entisols 91.153.645.21 sandloamy sand Duripan 90.935.563.51sandloamy sand Bt Boys76.9417.405.60loamy sand Average86.348.874.77

10. Bulk Density, AWC and OM Bulk Density: 1.08 g/cm3 Available Water Content: 0.23 cm 3 H 2 O/ cm 3 soil Organic Matter Content: 2.06 %

11. Soil pH, CEC & base saturation pH Using H 2 O: 4.62 Using CaCl 2 : 3.46 CEC (cmol c / kg) 1.19 % Base Saturation 13%

12. Soil Profile Summary Soil Texture: Sand (76-91%) Silt (3-17%) Clay (3-5%) - Affects Db and AWC Lowest CEC and base saturation Non-calcareous; acidic Soil horizons shallow and not well developed

13. Soil Profile Summary Texture= Sand (90-92%) Clay (3.5%) & Silt ( 5-5.5%) * Non-calcareous; Acidic * Well-developed forest floor * Soil Horizons shallow & not very developed

14. Plant Profile Predominant Overstory plants Quercus alba, Quercus rubra, Acer rubrum Understory plants included Pinus Strobus, Sassafras albidum, Hamamelis virginiana Groundcover plants included Pteridium aquilinum, Carex Pensylvanica, Gaylussacia bacata

15. Plant Factors Influencing Soil Slow Decomposition Nutrient Poor Litter High Content of Organic Acids

16. NO and NH Nutrient Pools

17. Nitrogen Exchange Nitrogen is often a limiting factor in the productivity of terrestrial ecosystems. Microbial activity fixes organic nitrogen into forms that are available to plants plants use fixed nitrogen to manufacture organic compounds, N returns to the microbes tied in organic compounds forming plant litter

18. Nitrogen Exchange N cycling is controlled by: Litter production, above and below ground Litter chemical composition Microbial community numbers and types Temperature and moisture affecting the activity of microorganisms

19. Role of Organic Matter (Carbon) Carbon supplied by plant litter limits microbial growth Amount of N released during decomposition reflects the “quality” of organic matter

20. The Connection Plant and microbial activity within terrestrial ecosystems is tightly linked through the exchange of C and N

21. Chemistry N is released from OM by heterotrophic soil organisms (bacteria,fungi, actinomycetes) in the form of ammonia R-NH3 + H2O  R-OH + NH4+ Ammonia can then be assimilated by plants, participate in ion exchange reactions or…

22. Chemistry …it can be oxidized by chemoautotropic bacteria to form nitrate 2 steps: NH4+ + 1 1/2 O2  NO2- + H2O + 2H+ NO2- + 1/2 O2  NO3-

23. Nitrifying Bacteria Only 3 genera carry out the first step, and only 1 genera carry our the second All nitrifying bacteria are –strictly anaerobic and –intolerent of low soil pH Thus, their activity is restricted in acidic conditions like the northern oak ecosystem

24. N and C Exchange in the Northern Oak Ecosystem Microbial biomass is very small Thus, so is the specific microbial respiration rate, indicating the relative efficiency of the microbial community to convert organic C to biomass. (higher = less efficient) sitemicrobial biomassspec resp units g C/g mg/g/d NH117.09215.04 NO20.84556.34

25. N and C Exchange in the Northern Oak Ecosystem The low biomass of microorganisms contributes to a small amount nitrogen produced. The acidity of the site may contribute to the very low amount of nitrate. siteincub NH4+incub NO3- unitsug N/g soil NH31.6727.35 NO23.270.32

26. N and C Exchange in the Northern Oak Ecosystem The ratio of C respired to N mineralized indicates the litter quality of a site. A high ratio indicates a good substrate for microbial growth, but little N released where it can be assimilated for plants. SiteC respired:N mineralized NH7.16 NO11.11

27. How does it all fit together? Fire from west burns through NO forest burn  quick release & loss of nutrients Vegetation = response to /100yr disturbance Less nutrients in oak litter  slow decomp. Canopy less dense  site drier than NH Less water  less weathering of soil