Phytoplankton Characteristics Common name
Diatoms Stonewarts, Desmids Greens Chrysophytes Cryptomonads Blue-greens Dinoflagelates Euglenoids
Division
Unit of Classification
Unit phylum classis Order family genus species variety forma Character -phyta -phyceae -ales -aceae latin latin latin latin Example Chlorophyta Chlorophyceae Chlorococcales Chlorococcaceae Chlorella vulgaris vulgaris tertia
Order Chlorellales
Chlorella
Scenedesmus
Pediastrum
CHRYSOPHYTA (GOLDENBROWN ALGAE)
The single cells, colonies or filaments are yellow, goldenbrown or rarely green. Motile cells usually have two anterior flagella of unequal length.
Common Genera Chlamydomonas Volvox
Class Chlorophyceae: Order Oedogonials
Oedogoniumlorophyceae:
Division Chlorophyta
Common Genera Chlamydomonas Volvox
According to different classification system, there are 8-13 divisions of algae represented in inland waters. Each division includes a wide range of vegetative and reproductive diversity, and in some cases almost identical taxa may reside in two different divisions—— Similar environmental pressures may have led to the evolution of similar traits in organisms with a fundamentally different origin.
Common Name Diatoms
Division Bacillariophyta
Common Genera Cyclotella Asterionella
Two main groups
Centric – radial symmetry
Pennate – bilateral symmetry
Common Name Diatoms
Phytoplankton Characteristics Common name
Diatoms Stonewarts, Desmids Greens Chrysophytes Cryptomonads Blue-greens Dinoflagelates Euglenoids
reflect colors of different groups
Some Concepts
• Assemblage: a group of populations or species of similar organisms that co-occur in a defined area • Community: an interactive assemblage of species occurring together within a particular geographical area • Association: repeatedly encountered assembly of species which were commonly found to co-occur
BACILLARIOPHYTA (DIATOMS) The single cells, colonies or filaments are yellow to light brown. The cell wall always consists of two overlapping silica shells (like a petri-dish).
1. Going to talk about specifics such as seasonal succession
2. Different groups are better or worse under different conditions e.g. Phosphorous levels or other nutrients 3. Vary in nutritional value with implications for the overall food web 4. Impact human health and recreation
Algae Classification System
Taxonomy(分类学)
What is taxonomy?
A discipline of biology concerned with naming and classifying the diverse forms of life
Why is it useful?
Classification schemes depends on reference Different physiological requirements and vary in response to physical and chemical parameters (e.g. light, temperature, nutrient regime)
Common Name Green algae
Division Chlorophyta
Common Genera Chlamydomonas Volvox
Most chlorophytes are aquatic, but some can live on the surface of snow, tree trunks, in soil, or symbiotically with protozoans, hydras, or fungi Extremely large and morphologically diverse group Class chlorophyceae: some of the most common and ecologically important freshwater algae (350 genera and 2650 living species)
Taxonomy
Kingdom 8 common divisions Phylum (Division) of phytoplankton Class Order Family Genus Species
1. Monera - bacteria, cyanobacteria 2. Protista - an intermediate between bacteria and other kingdoms 3. Fungi 4. Plantae - vascular plants, mosses 5. Animalia - rotifers, arthropoda
Division Bacillariophyta
Common Genera Cyclotella Asterionella
Excellent food source for plankton (Highly nutritious) even though most are sessile and associated with littoral substrates Heavy (sink) strongly tied to mixing patterns of lakes Cell is contained in a silica frustules (cell wall is made of glass) Cells reproduce asexually (Epitheca and hypotheca) until a small size threshold were they reproduce sexually
Common Name Chyrsophytes
Common Name Stonewarts Desmids
Division Charophyta
Common Genera Chara Micrasterias
Can be unicellular or multi-cellular Not of great ecological importance in food chain Chara Desmids (micrasterias)
People like to classify things (shift from morphology to molecular methods) Important to have classification system to understand ecology and evolution of systems
Common Name Green algae
Class Chlorophyceae:
Division Chlorophyta