1. Biomes

2. Weather - particular set of physical properties of the Earth’s troposphere:
Temperature, pressure, humidity, precipitation, sunshine, cloud cover, wind direction and speed
Climate – a region’s general pattern of atmospheric or weather conditions, including seasonal variations and weather extremes over a long period.
Biome – a large geographical region having a defining climate to which plants show a similar physiological adaptation.

3. Four Global Temperature Regimes
Hot
Tropical
Temperate
Subpolar
Polar
Cold

4. Four Plant Types
Succulent – vertical orientation on most parts, no leaves, store water, photosynthesis in tissue
Cactus
Broadleaf Evergreen – keep most of their broad leaves year-round
Tropical trees
Broadleaf Deciduous – drop their leaves when it gets cold (dry in the tropics)
Oak, maple, pecan
Coniferous (cone-bearing) Evergreen Plants – keep their narrow pointed leaves (needles) all year
Pine, spruce, fir

5. General Biome Types Forest – dominated by trees
A lot of precipitation needed
Scrubland – small deciduous trees and shrubs
Some precipitation needed
Grassland – dominated by grasses
Does not need as much precipitation as a forest
Usually needs disturbance to limit tree growth
Grazing, fire
Desert – dominated by succulents
Very little precipitation
‘For plants, precipitation generally is the limiting factor that determines whether a land area is desert, grassland, or forest.’

6. Temperature and precipitation regulate plant growth, thus the regional distribution of biomes.
Boundary lines between biomes are not as distinct as implied here.

7. Tropical, Temperate, or polar – Depends on Temperature
Forest, Grassland, or Desert – Depends on Rainfall

8. Tropical deciduous forest
Global air circulation affects local precipitation
Cell 3 South
Cold,
dry air
falls
Moist air rises — rain
Cell 2 South
Cool, dry
air falls
Cell 1 South
Moist
air rises,
cools, and
releases
moisture
as rain
Cell 1 North
Cell 2 North
Cell 3 North
Cold, dry
Polar cap
Arctic tundra
60°
30° 0°
Evergreen
coniferous forest
Temperate deciduous
forest and grassland
Desert
Tropical deciduous
forest
Equator
Tropical
rain forest
Tropical deciduous forest
A combination of insolation and precipitation determines global biome distribution

9. Net Primary Production of Terrestrial Biomes
NPP (g C/m2/yr)
Tropical Rain Forest
900
Tropical Dry Forest
675
Temperate Evergreen Forest
585
Temperate Deciduous Forest
540
Boreal Forest
360
Tropical Grasslands
315
Cultivated land (USA)
290
Chaparral
270
Prairie
225
Tundra
Desert 32
Extreme Desert
1.5

10. Rivers and Streams
Generally represent the excess of precipitation on land areas over evaporation from them.
Precipitation that falls is either evaporated, transpirated, enters the ground water supply, or flows down rivers
Flow is down-hill and varies seasonally
Related to rainfall and ice/snow melt
Beginning of a river = the source and the end of a river = the mouth
Discharge - volume of water passing a given point during a period of time
Channel Width X Depth X Velocity

11. Rivers and Streams
Flow velocity is important in determining abiotic and biotic components.
Flow related to slope and precipitation
Sediment type, current strength
The faster the flow, the more material can be transported in the water
Only certain organisms can withstand strong flow
Materials are transported by running water in three principal states
Dissolved matter
Suspended solids
Bed load

12. Stream Order
Used to classify a stream in relation to tributaries, drainage area, total length, and age of water. 1 2 3
Stream Order – Strahler Method
1  1 = 2
1  2 = 2
2  2 = 3
1  3 = 3
2  3 = 3
3  3 = 4
Mississippi River is classified as a 10th or 12th order stream.
Headwater stream classification matters

13. Major Rivers of The World
Name
Discharge 103 m3/sec
Length 103 km
Drainage Area 106 km2
Amazon, South America
212.40
6.44
5.78
Congo, Africa
39.65
4.70
4.01
Ganges-Brahmaputra, India
38.50
2.90
1.62
Yangtze, China
21.81
5.98
1.94
Yenisei, USSR
17.39
5.54
2.59
Mississippi North, America
17.30
6.02
3.22
Mekong, Asia
11.04
4.00
0.80
Nile, Africa
3.10
6.65
3.35

14. You will be required to draw a map of the major rivers of the Mississippi River Basin as part of exam 1.

15. Mississippi River (Main Stem) Atchafalaya River (Distributary)
Distributary – A smaller channel that takes water away from the main stem river.
Mississippi River (Main Stem)
Atchafalaya River (Distributary)
Flow

16. Large River Floodplain Ecology

19. Construction of levees along the Mississippi River and many of its tributaries has severed the river from over 90% of its floodplain, denying fish and other aquatic species access to millions of acres of foraging, spawning and nursery habitat.
Miss. Dept. of Archives and History

22. Net Primary Production (measure of available energy)
Estuaries
Swamps and marshes
Tropical rain forest
Temperate forest
Northern coniferous forest (taiga)
Savanna
Agricultural land
Woodland and shrubland
Temperate grassland
Lakes and streams
Continental shelf
Open ocean
Tundra (arctic and alpine)
Desert scrub
Extreme desert
800
1,600
2,400
3,200
4,000
4,800
5,600
6,400
7,200
8,000
8,800
9,600
Average net primary productivity (kcal/m2/yr)

23. Where Are We?
Ponchartrain
Atchafalaya N
Barataria
Terrebonne

24. Terrestrial Vegetation Growth During Low Water
Nutrients Released During High Water

25. More Nutrients = More Plants = More Animals
Simply put:
More Nutrients = More Plants = More Animals
= Happy Cajuns!!
Inundation of the floodplain is the mechanism of energy and nutrient transfer from terrestrial vegetation to the aquatic community.

26. Swamps are not wastelands!

27. The Floodplain Extends to the Coast
All flowing Louisiana waterways eventually drain to the Gulf of Mexico
Energy and nutrients from floodplain terrestrial vegetation are carried to coastal waters and sustain estuarine and coastal production
The coast is ultimately supported by floodplain ecosystem processes

28. Barataria-Terrebonne National Estuary
Baton Rouge
New Orleans
Thibodaux
Houma
Grand Isle
Port Sulphur

30. Three General Types of Water
Brown
High flow, lots of sediment, fairly high oxygen levels, riverine
Green
Low flow, stratification, very high surface oxygen levels, highly productive, lacustrine
Black
Low flow, very low surface oxygen levels, not productive, swamp

31. Backwater Interior Lakes Mainstem
December
June
August

32. Oxygen Level Controls Photosynthesis produces oxygen:
Solar Energy + CO2 + H20  C6H12O6 + O2
Respiration consumes oxygen:
C6H12O6 + O2  CO2 + H20 + chemical energy(ATP)

33. What is Hypoxia Dissolved Oxygen (DO) less than 2.0 mg/L
Normoxic = DO > 2.0 mg/L
Generally, most fish can not tolerate hypoxic conditions for long periods.
Gar, bowfin (choupique), bullheads can

34. Why Hypoxia?
During low water times, the dry lands are extremely fertile and grow a lot of plants.
When the spring floods come and temperatures rise, bacteria begin to decompose the vegetation on the floodplain floor.
Bacterial respiration is what removes the oxygen (lack of flushing in backwater habitats contributes).
Respiration rates exceed photosynthetic rates.

35. When and Where Is Hypoxia?
Generally found during high water times when temperatures are warm.
Backwater areas (away from the mainstem river).
Low flow

37. Eventually the swamp drains and backwater areas become very productive.

39. How Do ‘Unproductive’ Areas Support Living Populations?
Submerged Aquatic Vegetation
Oxygen Refuge
Productive microhabitats

40. Fish and Aquatic Vegetation
Densities of young fish are often greater in aquatic vegetation than in adjacent open water

41. Mean Surface Dissolved Oxygen in Open Water and Plants at Each Site
Normoxic
Hypoxic
Green
Brown
Black

42. Atmospheric oxygen diffuses into water
Air-Water Interface
Atmospheric oxygen diffuses into water
Fish ‘pipe’ at the microsurface layer
Low DO Water

43. How Do ‘Unproductive’ Areas Support Living Populations?
Detritus-Based Production
Decomposers (e.g., bacteria) transfer energy stored in old organic matter to consumers
Insects, crawfish
Low-oxygen tolerant organisms
Gar, bowfin (choupique), bullheads

44. Energy flow through an aquatic ecosystem.
From Cole 1988, Waveland Press

45. Terrestrial leaf litter/detritus input during Flood Pulse
Detritus Based Food Web.
From Cole 1988, Waveland Press

46. Major Ocean Currents Effect on Climate
Insolation (and associated effects), the Earth’s rotation, plus difference in water density, create warm and cool currents.

47. Ocean currents can affect local climate

48. Oceans
Coastal regions are much more productive than non-coastal areas.
Rich nutrient input from coastal rivers
Most of the worlds great fisheries come from the continental shelf
Too many nutrients can lead to algal blooms, which may deoxygenate the water (eutrophication)

49. Oceans Salinity averages 35 ppt (full strength sea water).
Due to high concentrations of sodium and chloride
Ocean is more than salt and water, but most ocean waters are very poor in nutrients
Phosphate, nitrate, ammonium, iron
Oceans cover ~71% of Earth, but only account for 50% of the Earth’s primary production.
Biological deserts not limited by water, but by nutrients
Unlike terrestrial biomes, production is not higher at equator and lower at the tropics –respond to nutrient concentrations like upwellings.

50. Upwelling Productivity
Global estimates of the primary production required to sustain fisheries in five marine ecosystems.
Production is highest in shallow well-lit coastal waters and upwellings.

51. Upwelling Productivity
Primary production dependent on nutrients brought from the ocean depths.
This is a function of ocean currents driven by wind pattern and the Earth’s rotation
A disturbance to wind patterns can affect the primary production of upwellings, which can have an effect ‘up the food chain.’

52. Productivity Aquatic Productivity relies on nutrient input/cycling
Whether from terrestrial ecosystems or upwellings

53. The River Continuum Concept
Energy flows downstream
CPOM – course particulate organic matter
FPOM – fine particulate organic matter
UPOM – ultra-fine particulate organic matter
DOM – dissolved organic matter
Invertebrate Community Groups
Shredders – Feed on CPOM
Collectors – Feed on FPOM and UPOM
Grazers – Feed on algae/periphyton growth
Predators – Feed on other invertebrates

54. 1 – 3 order: P/R < 1.0 4 – 6 order: P/R > 1.0
Energy rich allochthonous materials are entering the system
Collectors, shredders
4 – 6 order: P/R > 1.0
More materials are produced by photosynthesis than are used by respiration
Collectors, grazers
> 6 order: P/R < 1.0
Collectors, predators

55. What did the fish say when it hit a brick wall?
Dam!

56. River Dam(n)s Block passage of migratory species
Anadromous, catadromous
Reduce stream sediment load
How can this affect ecosystems?
(Freeman 2003)

57. Spawning Migrations
Salmon and trout bring marine derived nitrogen (MDN) upriver
Important for offspring
Important source of nutrients for many animals
How does a decrease in salmon and trout (and other anadromous fishes) populations affect ecosystems
(Willson and Halupka 1995)

58. Salmon Carcass Replacement Program
Program places harvested salmon carcasses in streams
Could be placing PCB’s and other pollutants into the ecosystem
(Missildine 2005)