1. FOREST BIOMES (ECOSYSTEMS)

2. Characteristics of Earth’s Forests
Area
(km2)
NPP
Biodiv-
ersity
Forest
Type
Where?
Rainfall
Soil
gC/km2/yr
Immature, but
abundant
minerals yet
to be released
High N
Latitudes
(50-60 °N)
Low
20-50
cm/yr
Boreal
12 M
300 M
Low
Rich, fertile,
abundant
nutrient
reserves
Mid-
Latitude
(30° - 50°)
Moderate
50 to 100
cm/yr
Temperate
12 M
500 M
Moderate
Poor, highly
leached. Most
nutrients
recycles
Low
Latitude
(0 - 30°)
High
2 to 10
m/yr
Tropical
Rainforest
17 M
1000 M
High

3. Boreal Forests: slow growing, cold, 1/2 year low light, shallow, immature, but mineral-rich soils. Low plant and animal diversity.
Capable of sustained harvest, but low yield (slow growth)
Temperature Forests: Mixed deciduous hardwoods and evergreens, fertile soils. Resistant to disturbance: if cleared, rapid recolonization. Sustained yield OK in most regions.
Tropical Rainforest: Closed canopy, high rainfall. Most in Brazil (Amazonia), central West Africa (Congo, Zaire), Indonesia and Madagascar. Also Central America, Angola, Peru, Bolivia, India and scattered outliers.

4. NPP: Net Primary Productivity
What is the net annual production of organic matter by a particular ecosystem, usually measured in the amount of Carbon fixed as organic matter.
Net means the total fixed minus the total respired.
gC/km2/yr is the (net) grams of carbon fixed over each square kilometer in an average year.

6. Percentage area covered by different ecosystems

7. NPP (gC/m2/yr) for different ecosystems

8. 70%
Percentage net NPP (gC/m2/yr) for different ecosystems 3%

10. How a geologist views a tree.…Key variables:
Leaf area index
Rooting depth
Water-holding capacity of the soil.

11. * The process whereby natural forests are cleared
through logging and/or burning, either to use the
timber or to replace the area for alternative uses.
MAJOR CONCERNS ARE:
* Loss of biodiversity
* Global warming (burning releases CO2)
* Climate impacts

12. Deforested
Forested

13. ROLE OF THE FOREST