Reminder 1: Your 5-10 photos are due today ! …most of you already have them

1. Reminder 1: Your 5-10 photos are due today ! …most of you already have them Worth 5 Points ! Also, make sure you have 5-10 photos for your longer Plant-Report !

2. Reminder 2: Exam-3 is next Friday! Chapter 37 (all) Chapter 38 (pp. 781-784, 787-792) and related pages on water, chemistry, etc. Chapter 39 (pp. 795-801) …this is what we will be covering the next three lectures

3. Reminder 3 : Office Visits need to be completed by next Thursday! …about 1/3 of class is finished ..only takes about a half-hour. …e-mail for appointments. Worth 5 Points !

4. Announcement: Lab Next Week = Field Trip ….to Louisville Nature Preserve ! …so dress appropriately

5. Chapter 38 - Plant Nutrition

6. Joke

7. p. 782 Pages 41-58 Page 153

8. * There are other minerals that are required by animals (but not plants): Sodium Iodine* Chromium* Selenium* Cobalt* Fluorine * note that some of these can occur as radioactive isotopes

9. Typical example of Nitrogen Deficiency

11. ‘Wooden Barrel Model’ demonstrating the Principle of Limiting Factors of plant growth

12. * Now, Limiting Factor Is Potassium add nitrogen Factors For Optimal Plant Growth Limiting Factor is Nitrogen

13. p. 782 Most Often Needed

14. * Numbers = % Fertilizer Weight

15. Seeds have a complete supply of nutrients

16. Early growth depends a lot on Nitrogen

17. Root growth depends more on Phosphorus & Potassium Ginseng

18. Flowers & Fruits also need more Phosphorus & Potassium But it really depends on species

19. Plants absorb just about any mineral elements that happen to be in the soil… * Some plants are even “Hyperaccumulators” (absorbing more than 100x more chemical than what is in the soil)

20. Locoweed (Colorado) absorbs selenium. If eaten by cattle or horses it cause tremors & lack of coordination (‘loco’ is spanish for crazy). This plant is in the Legume family.

21. Dr. Chris Anderson, New Zealand, is mining gold by growing plants near old gold mines (in the ‘tailing waste’) He is finding concentrations of gold at 100 ppm in the plants. The trick is simply to extract the gold cheaply.

22. * ‘Phytoremediation’ = using plants to reduce pollution • Absorbs pollutant and either • metabolizes it (breaking it down) or • at least, concentrates it in the plant. • Reduces erosion of the polluted soil • by the action of the roots holding on • to the soil.

23. Botanists conducting research on Phytoremediation

24. old Army Ammunition Dump St. Paul, Minnesota

25. Chernobyl Nuclear Power Accident, 1986 Float sunflower plants in a pond near the nuclear power plant. The plants absorbed 8000x more radioactive cesium, and 2000x more radioactive strontium than what was found in the pond!

26. Lead Pollution from leaded-gas, lead-paints, factories Darker color = more lead

27. Plants are also being ‘genetically engineered’ to absorb more pollutants…

28. * Three Factors that can affect plant uptake of nutrients: 1) Soil pH = concentration of H+ • Acid Soils Tend to Have: • Higher Rainfall • Higher Amounts of Decaying Plant Debris in Soil • Alkaline Soils Tend to Have: • Lower Rainfall • Lower Amounts of Decaying Plant Debris in Soil Which type of soil do you think Kentucky has?

29. * The way to overcome acidity = ….add Lime (CaCO3) (calcium carbonate) • In Acidic soils, some minerals become deficient • (like Phosphorus and Molybdenum) • Other minerals are more soluble at higher acidity • and so are taken up more readily by plants: • Iron • Zinc • Manganese • Magnesium • Boron • Copper • One mineral (aluminum) can even become toxic • to the plant because it is so soluble.

30. * Three Factors that can affect plant uptake of nutrients: 2) Biological Activity • Three primary examples: • Fungi • Bacteria • Earthworms

31. Mycorrhizae (fungi)

32. Announcement: Lab Next Week = Field Trip ….to Louisville Nature Preserve ! …so dress appropriately

33. Meet Here 12:10

34. * Symbiotic Root Nodules = Nitrogen-fixing bacteria living inside specialized root structures Bacteria Only members of Legume Family (pea, bean, lentils, clover, alfalfa, soybean, peanut, etc.)

35. * …only occurs in certain bacteria

36. An acre of alfalfa can capture up to 200 lbs of nitrogen per year !

38. The “Dead Zone” in the Gulf of Mexico is due to overstimulated phytoplankton growth (called ‘blooms’). When they die and settle to bottom of ocean. Their decompostion consumes too much oxygen, which leads to fish death, etc. *

39. * Earthworms Giant earthworm (Australia) One earthworm digests 1 ton of soil per year • Aerates soil • Recycles nutrients Castings

40. Joke Three Factors that can affect plant uptake of nutrients: * 3) Soil Texture: “The relative concentrations of Sand, Silt, Clay” Sand = .02 - 2 mm diameter Silt = .002 - .02 mm Clay = less than .002 mm

41. Sand

45. * • Advantages of sandy soil: • - good aeration • good drainage • can’t be compacted • - warms easily • Disadvantages of sandy soil: • - poor water-holding capacity • - poor nutrient-holding capacity

46. Clay

47. Has few air spaces because particles fit together so closely

49. * Pure clay can be molded into any shape you want… …and when it dries doesn’t “crack”….that shows how few air/water spaces there are.

50. * Clay is Negatively-charged.... …so attracts Positively-charged minerals (cations). This represent a ‘storage facility’ for cations.