Transcript Aquatic_Ecology_lab_5

Aquatic Ecology374
First Term of year 1432-1433
Nuha AL-Abdulhadi
Dr.promy
lab 5
Macrophytes
Macrophytes: the aquatic
macroscopic plants confine
themselves to the shallow zone
of water.
A macrophyte is an aquatic plant that grows in or near water,
or floating.
- In lakes macrophytes provide cover for fish and substrate for
aquatic invertebrates, produce oxygen, and act as food for
some fish and wildlife.
-A decline in a macrophyte population may indicate water
quality problems. Such problems may be the result of excessive
turbidity, herbicides, or salinization.
-Conversely, overly high nutrient levels may create an
overabundance of macrophytes, which may in turn interfere
with lake processing.
Monitoring macrophyte levels are easy to sample, do not
require laboratory analysis, and are easily used for calculating
simple abundance metrics.
These plants can be emergent, submergent or floating.
Macrophytes
Importance of Macrophytes
in the aquatic environment
 Aquatic macrophytes play a vital role in healthy ecosystems. They
serve as primary producers of oxygen through photosynthesis,
provide a substrate for algae and shelter for many invertebrates, aid
in nutrient cycling to from the sediments, and help stabilize river
and stream banks.
Biological filtration is an increasingly popular method of sewage
treatment; some aquatic plants are being used to remove nutrients
and reduce concentrations of phosphorus and nitrogen from raw
sewage or from the effluent sewage treatment facilities. Aquatic
plants are also able to absorb other substances, including pollutants
such as phenols.
-duckweeds(type of macrophyte) are known to reduce mosquito
numbers, which has the added benefit of decreasing the incidence of
insect-borne diseases.
Disadvantages:
Fishing and navigation is another concern, as
tall emergent plants can prevent access for
shoreline fishing.
. Several human diseases are transmitted
through intermediate hosts that are either
dependent upon certain macrophytes
Schistosomiasis (African sleeping sickness) is
one example; the intermediate host is an
aquatic snail that lives among aquatic
vegetation.
Types of Macrophytes:
1-Calss : Dicotyledons
- also known as dicots, are a group of
flowering plants.
- Leaves are typically articulately veined
1-ex :Nymphoides cristatum
1-ex :Nymphoides stellata
Leaves glabrous(without hair),
flowers blue, white, rose or
purple, open in the morning .
2-ex:Nymphoides indicum
plant large, leaves upto 30cm
in diameter, long unequal ;
white with yellow center ,the
surface with long white hairs
.
Ex:3- Ipomoea aquatica
plant aquatic, annual or
biennial; stem hollow,
corolla pinkish ,darker in
the throat
2-Class:Monoctyledons
-leaves are parallel veined
Flowers with their parts usually in
three or multiples of three (trimerous)
1- ex:Hydrilla verticillata
Stem branched, leaves usulally
linear to lanceolate ,entire or
toothed, flowers minute with
three sepals, petals .
It is a perennial
monocotyledon with thick,
soft leaves that form a
rosette. It floats on the
surface of the water, its roots
hanging submersed beneath
floating leaves. The leaves
can be up to 14 cm long and
have no stem. They are light
green, with parallel veins,
wavy margins and are
covered in short hairs.Also
called water cabbage.
2-ex:Pistia stratiotes
3:ex:Spirodela polyrhiza
Common in stagnant waters;
Spirodela species are free-floating
thalli, 2-5 plants may remain
connected to each other. Plants are
green, but may have a red or brown
underside. Multiple roots (7 to 12)
emerge from each thallus
.Commonly called duckweed.
.
4-ex:Potamogeton pectinatus
Rhizome tuber bearing; stem
leaves sub merged, tips
pointed,1-3 veined; (Example
of pond weed)
NUHA