Energy Sources in Aquatic Ecosystems Flashcards
What are the two types of energetic resources found in aquatic systems?
Autochthonous and allocthonous
This type of resource is found within the body of water
Autochthonous
These are not as major primary producers in aquatic systems as they are in terrestrial systems
Plants
Aquatic food webs are primarily based on these primary producers
Algae/diatoms
These are incredibly important single-celled protists found in aquatic systems
Diatoms
What percent of global carbon fixation is done by diatoms?
20%
What are diatom shells called?
Frustrule
What are diatom frustrules made of?
Silica (SiO2)
What are three functions of diatom frustrules?
Protection, light absorption, distinctive shape
Diatoms are relatives of this type of algae
Brown algae
Are diatoms closely related to plants?
No
How many valves are frustrules made of?
2
What is one of the best ways to ID a diatom?
By its frustrule
Are both frustrule valves the same size?
No
Do diatoms occasionally discard their frustrules?
Yes
What is a human use of fossilized diatom frustrules?
Diatomaceous earth
Are diatoms relatively poorly competitive photosynthesizers?
No
What is the limiting substance for diatom growth in the water?
Silica
What are four types of algae that serve as primary producers in aquatics?
Blue-green algae, red algae, brown algae, green algae
Which type of algae are bacteria?
Blue-green algae
Which three types of algae are protists?
Red, brown, green algae
Algae growing on rocks are known as this
Periphyton
Algae found in the water column are known as this
Phytoplankton
These algae were the first and best to ever make oxygen
Blue-green algae
Blue-green algae can form these, though they are not multicellular
Long chains
Blue-green algae chains have one different cell, known as this
Heterocyst
Blue-green algae heterocysts are very important to this part of the nitrogen cycle
Nitrogen fixation
Blue-green algae can produce this during harmful algal blooms
Neurotoxin
This type of algae grows on rocks
Epilithon
This type of algae grows on plants
Epiphyton
This type of algae grows on wood
Epidendron
This type of algae grows on sediment
Epipelon
This type of algae grows on sand
Episammon
This type of algae grows on animals
Epizoon
Different types of algae grow together to form these
Biofilms
What are three processes that biofilms are resistant to?
Loss, abrasion, disruption
Biofilms can form this to catch food particles and prevent them from washing away
Sticky matrix
Biofilms can be thought of as the aquatic version of these
Forests
Aquatic plants are also known as these
Macrophytes
Most freshwater plants tend to be this type of plant
Angiosperm/flowering plant
Is pollination easy in aquatic systems?
No
What are four reasons why pollination is difficult for aquatic plants?
- Seeds get washed downstream; 2. Pollinators are less able to get to open water; 3. Flowers are difficult to support out of water for wind pollination to be effective; 4. Sediment is an unstable growing medium
What are five limitations on plants in aquatic systems?
Light, water velocity, settlement rate, other macrophytes, pH
What are four things that do not limit plants in aquatic systems?
Water, CO2, nutrients, herbivory
When are plants important to aquatic systems?
When conditions are relatively ‘good’
What are two important sources for food webs in aquatic systems?
Algae (mostly diatoms) and tree leaves
This type of resource is found outside the body of water
Allocthonous
This is made up of decomposing organic matter suspended in water
Particulate organic matter (POM)
This type of particulate organic matter is made up of large matter, such as whole leaves
Coarse particulate organic matter (CPOM)
This type of particulate organic matter is made up of large matter that has been shredded down to smaller matter
Fine particulate organic matter (FPOM)
This type of organic matter has been reduced to soluble size
Dissolved organic matter (DOM)
Evolution has produced solutions to processing these when they regularly fall into the water
Leaves
These leach out from dead leaves into the water within 2 days
Soluble nutrients
These two types of organisms colonize dead leaves in the water immediately
Bacteria and fungi
These invertebrates begin to break up dead leaves in the water at around 2 weeks
Shredders
This ratio can vary considerably among leaves in the water
C:N ratio
What are three different terms for woody debris found in streams
Large woody debris (LWD), coarse woody debris (CWD), large organic debris (LOD)
What are five effects of wood on stream systems?
- Food source; 2. Influences stream morphology; 3. Decreases water velocity; 4. Traps sediment; 5. Creates habitat
What is another name for a wood-eating organism?
Xylivores
Is wood an easily-accessed source of nutrients?
No
This substance makes wood difficult to digest
Lignin
Do most organisms that eat wood eat other materials as well?
Yes
These organisms are extremely important to aquatic systems
Terrestrial insects
Can terrestrial insects alone support stream fishes?
Yes
How do terrestrial insects link aquatic and terrestrial systems?
By bringing nutrients onto land from their aquatic larval stages or into water via predation by fish
Some fish can link freshwater systems with these systems
Marine systems
Can fish move nutrients around within a system?
Yes
Are most migratory species of fish thriving today?
No
Are fish highly important to nutrient inputs?
No
