Transcript Aquatic Plants ppt email version

Aquatic Plants
Aquatic Ecology
Mr. Werner
PLANTS (MACROPHYTES)
TAXONOMY and DIVERSITY
Macro-algae (Chara) – Several forms
Flowering Plants – 2 dozen families (several hundred species)
4 categories: Floating unattached, Floating attached, Submerged, Emergent
AQUATIC MACROPHYTE HABITAT
Attached, Floating, submerged, emergent,
SWIMMING AND ESCAPE BEHAVIOR
none
FEEDING PREFERENCES AND BEHAVIOR
Photosynthesis
LIFE CYCLE AND DIAPAUSE
The seed bank
ECONOMIC IMPORTANCE AND MANAGEMENT
Large: Ecologically important
Sometimes nuisances
EXTERNAL STRUCTURE, APPEARANCE
and ANATOMY
Typical plant structures:
roots (rhizome, holdfast)
stem (single cell in macro-algae)
leaves
flowers
“Plants are inside-out animals.”
Tim Allen
The importance of aquatic macrophytes in
freshwater systems
• Aquatic macrophytes play a vital role in ecosystems.
• They are primary producers and an important food
source.
• They provide a substrate for algae and shelter for
invertebrates and young fish.
• They offer nesting sites or birds and mammals
• They aid in nutrient cycling.
• They catch sediments and help stabilize river and
stream banks.
Rhizomes
1. Floating unattached plants
• Roots, if present,
hang free in the
water and are not
anchored to the
bottom.
Duckweed
2. Floating attached plants
• …have leaves which
float on the surface,
but their stems are
beneath the surface,
and their roots
anchor the plant in
the substrate.
3. Submerged plants
• … the entire plant is
below the surface.
Elodea nuttallii
4. Emergent aquatic macrophytes
• …have roots below
and stems and leaves
above the water’s
surface.
Sedges - Carex
b.
For Picture see Fig. 5.6 p.136 in
Textbook
a.
a.
Sedge - Wetlands
b.
Grass – Emergent
c.
Lily pads – Floating Attached
d.
Sundew - Emergent
e.
Duckweed – Floating Unattached
c.
d.
e.
Representative of aquatic
submerged macrophytes
For Picture see Fig. 5.7 p.136 in Textbook
Chara (macroalgae)
Pond weeds (narrowleafed water weed)
Boad-leafed water
weed
Utricularia (bladder
wort)
Milfoil
(Myriophyllum)
Life Cycle
• Reproduce once a year
• Macro-algae = release motile gametes
• Flowering Plants = flowers on stalks,
pollinated by wind or insects/birds.
• Seeds mature during warm season & enter
diapause stage in winter.
The speed of the water determines the
type of plants found.
• Fast water
encourages low,
encrusting forms
Lentic Systems
• Slow flowing or
lentic bodies can
have large leafy
forms present.
Factors affecting plant growth
• Light is the most important factor in determining the
presence of plants
• Light levels beneath the surface can be affected by
many factors such as:
–
–
–
–
–
Depth
Turbidity (sediment)
Shading (trees etc.)
Water color (chemical staining)
Ice formation