Transcript Temperate Forests - Blue Valley Schools

Temperate Forests
Climate
• Named for their
occurrence at MidLatitudes
• Extreme fluctuations
in daily and
seasonal
temperatures and
precipitation
Forest Biotic Structure
• Upper Canopy Layer
Dominant Trees
• Lower Canopy Layer
Saplings & Understory
Trees
• Shrub Layer
Woody Shrubs
• Ground Layer
Herbs, Ferns, and Mosses
Ground Layer Decomposition
• Fungi, bacteria, and
Soil Invertebrates
act to recycle the
nutrients from
leaves and trees
limbs back into the
soil
• This is the most
diverse layer of the
forest
Symbiosis & the Forest
• Mycorrhizae
Fungi that have
developed beneficial
relations with the
tree roots providing
them water and
nutrients for sugars
• Lichens
Fungi and algae that
live on tree bark
Forest Abiotic Factors
• Sunlight,
Temperature, and
Humidity change
seasonally
• These factors may
effect the stomatal
densities of forest
plants
Spring
Summer
Fall
Winter
Secondary Growth
• The Vascular Cambium is responsible for creating
new xylem and phloem tissues
• Xylem is thick and is created to the inside of the tree
with identifiable annual rings
• Phloem thin and is created to the outside and part
forms protective bark
Xylem Growth Rings
• During the Spring
when there is
sufficient water and
sunlight the xylem
tubes are large
• As precipitation
decreases in
Summer the xylem
tubes produced are
smaller in size
Old Growth & Secondary
Forests
• Old Growth Forests
show variation in tree
ages, contain more
woody debris, fallen
logs, and a greater
diversity of animal life
• Secondary Forests
have young
homogeneous aged
tree stands with little
diversity and developed
layers
Human Impacts
• Lumber and Paper
• Cleared for
Agriculture
• Mining
• Human
Development
• Global Warming