1. Announcements Kevin and I will hold office hours together today in Girvetz 2307 Kevin and I will hold office hours together today in Girvetz 2307 Michael Pollan article to read for section this week Michael Pollan article to read for section this week

2. Summary from Friday Definition of soil Definition of soil Soil development Soil development additions, losses, transformations, and translocationsadditions, losses, transformations, and translocations Classification of soil Classification of soil 12 different orders12 different orders Factors of soil formation: Cl.O.R.P.T.H. Factors of soil formation: Cl.O.R.P.T.H. Biomes Biomes function of temperature and moisturefunction of temperature and moisture

4. Two-Minute Quiz During your spring break you decide to take a road trip through 18 states in 7 days. Early one morning in the middle of the week you wake up and realize that you can’t remember where you are. You step outside to investigate your surroundings, and notice a lovely road cut where the soil profile is visible from “O” horizon to bedrock.

5. Here are your observations: The soil is dark red and clayey. The soil is dark red and clayey. The profile is deep. The profile is deep. There are rolling hills, but no sharp peaks in the distance There are rolling hills, but no sharp peaks in the distance The temperature is 65° F. The temperature is 65° F. The air is humid, and the vegetation is lush. The air is humid, and the vegetation is lush.

6. Where are you? a) upstate New York b) near Ames, Iowa c) down a backcountry road in Georgia d) along the coast of Maine e) near the border of New Mexico in Arizona

7. Biome: A large climatic region where plants are similar to each other

9. What is missing?

11. Arctic Tundra:  Short growing season  Intense cold  Strong winds  Permafrost  Low primary productivity  Slow decomposition

12. Boreal forest:  Cold winters, warm summers  Cone-shaped trees - shed snow - catch light  Peatlands - slow decomposition  Fire

13. Temperate forest:  Evergreen and deciduous  Intermediate temperature  Adequate moisture  Few constraints on growth High primary productivity

14. Grasslands:  Continental regions - hot summer, low rainfall  Fires  Grazing

15. Deserts:  North and south of tropics  Dry  Hot or cold Organisms have adapted to this environment

16. Plant adaptation to hot environments: Physical Structure

17. Plant adaptations: Physiology Stomata must be open to take in CO 2 Stomata must be open to take in CO 2 Open stomata = water loss Open stomata = water loss How can a plant minimize water loss? How can a plant minimize water loss? Keep stomata closed as much as possibleKeep stomata closed as much as possible Open only at night = CAM plantsOpen only at night = CAM plants Cactus, some epiphytes, succulentsCactus, some epiphytes, succulents Open only a little bit = C 4 plantsOpen only a little bit = C 4 plants Some grassesSome grasses

19. Which grasslands are likely to be C 4 ?

20. Tropical Rainforests

21. Tropical rainforests:  Near the equator  Hot  Moist conditions  Tight cycling of nutrients - soils are actually quite poor  High primary productivity  Fast decomposition

22. Where is Santa Barbara?

23. Chaparral or Mediterranean-type Strong seasonality Strong seasonality Hot, dry summersHot, dry summers Mild, wet winters  high productivityMild, wet winters  high productivity Fires feed on large fuel supply Fires feed on large fuel supply

24. Announcements I will be gone on Friday – Theresa and Kevin will be giving presentations I will be gone on Friday – Theresa and Kevin will be giving presentations Read the Michael Pollan article for section. It is now available online too. Read the Michael Pollan article for section. It is now available online too.

25. Summary from Monday Biome= climatic region where the vegetation is similar Biome= climatic region where the vegetation is similar Hadley Cells Hadley Cells Terrestrial Biomes Terrestrial Biomes Arctic TundraArctic Tundra Boreal ForestBoreal Forest Temperate ForestTemperate Forest GrasslandGrassland Desert- physical and physiological adaptations of plantsDesert- physical and physiological adaptations of plants Tropical RainforestTropical Rainforest Mediterranean/ChaparralMediterranean/Chaparral

26. What is missing?

27. Aquatic Ecosystems Streams and Rivers Streams and Rivers Lakes Lakes Estuaries Estuaries Freshwater wetlands Freshwater wetlands Oceans Oceans

28. Streams and Rivers

29. 5 th order 4 th order 3 rd order 2 nd order 1 st order (headwaters)

30. How do large and small streams differ? Low stream order (i.e., 1 st or 2 nd order) Low stream order (i.e., 1 st or 2 nd order) Small, narrow, shallow Small, narrow, shallow Steep, fast-flowing rocky bottom Steep, fast-flowing rocky bottom Detritivore community breaks down litter Detritivore community breaks down litter High stream order (i.e., 4 th or 5 th order) High stream order (i.e., 4 th or 5 th order) Big, wide, deep Big, wide, deep Shallow slope, slow flowing Shallow slope, slow flowing Processed litter comes from upstream Processed litter comes from upstream

31. Production vs. Biomass Pyramids Primary Producers Herbivores Carnivores

32. Production vs. Biomass Pyramids Primary Producers Herbivores Carnivores Standing Biomass Primary Producers Herbivores Carnivores Productivity

33. Production vs. Biomass Pyramids Primary Producers Herbivores Carnivores Standing Biomass Primary Producers Herbivores Carnivores Productivity How do these pyramids differ in terrestrial vs. aquatic ecosystems?

34. Light Penetration in Lakes Secchi disk Euphotic zone Aphotic zone Sediment eu: well or good a: without

35. Thermal Stratification of Lakes Epilimnion Hypolimnion Sediment Summer Thermocline

36. Thermal Stratification of Lakes Epilimnion Hypolimnion Thermocline Sediment Epilimnion Hypolimnion Sediment (wind) SummerFall

37. Thermal Stratification of Lakes Epilimnion Hypolimnion Thermocline Sediment Well-mixed profile Sediment Epilimnion Hypolimnion Sediment (wind) SummerFall Winter

38. Thermal Stratification of Lakes Epilimnion Hypolimnion Thermocline Sediment Well-mixed profile Sediment Well-mixed profile Sediment Epilimnion Hypolimnion Sediment (wind) SummerFall Winter Spring

39. Thermal Stratification and Oxygen Well-mixed profile Sediment Epilimnion Hypolimnion Sediment Summer Winter

40. Phytoplankton and abiotic factors in a lake

41. Oligotrophic vs. Eutrophic Lakes

42. Wetlands: where water meets land All wetlands are ecotones Salt marshes: costal, brackish Salt marshes: costal, brackish Swamps: wooded, fresh water Swamps: wooded, fresh water Fens: external water and nutrient inputs Fens: external water and nutrient inputs dominated by sedges dominated by sedges Bogs: little external nutrient input Bogs: little external nutrient input dominated by sphagnum moss dominated by sphagnum moss

43. Wetland Biogeochemistry

44. When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic Wetland Biogeochemistry

45. When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic Demand for O 2 is still high Demand for O 2 is still high Wetland Biogeochemistry

46. When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic Demand for O 2 is still high Demand for O 2 is still high Other minerals containing oxygen get reduced Other minerals containing oxygen get reduced Wetland Biogeochemistry

47. When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic Demand for O 2 is still high Demand for O 2 is still high Other minerals containing oxygen get reduced Other minerals containing oxygen get reduced Reduction is when a compound gains an electron- in this case by giving up an O 2 atom Reduction is when a compound gains an electron- in this case by giving up an O 2 atom Some molecules release O 2 more easily than others Some molecules release O 2 more easily than others Wetland Biogeochemistry O 2  NO 3 -  Fe(OH) 3  MnO 2  SO 4 2-  CO 2

48. When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic When land is flooded, O 2 gets used up by decomposers and the soil becomes anaerobic Demand for O 2 is still high Demand for O 2 is still high Other minerals containing oxygen get reduced Other minerals containing oxygen get reduced Reduction is when a compound gains an electron- in this case by giving up an O 2 atom Reduction is when a compound gains an electron- in this case by giving up an O 2 atom Some molecules release O 2 more easily than others Some molecules release O 2 more easily than others If the water level drops, O 2 enters the soil again, and the reduced substances can get oxidized If the water level drops, O 2 enters the soil again, and the reduced substances can get oxidized Wetland Biogeochemistry O 2  NO 3 -  Fe(OH) 3  MnO 2  SO 4 2-  CO 2