Aquatic Biomes

Wetlands

Areas where the soil is saturated with water. Plants have adapted to living with roots submerged in water.

- made up of marsh, swamp, and bog

Salinity = >0.5 ppt

Wetlands - Threats

1) Urban Development and Draining - Fills marshes and swamps to clear land for housing

2) Hydrological Alterations - dams, water-division, etc.

Marsh

dominated by grasses and reeds

Swamp

dominated by trees and shrubs

Bog

acidic wetland, moss (sphagnum)

Benefits of wetland

1) Stores excess water during storms, lessening floods

2) Recharges groundwater by infiltrating rainfall water into soil

3) Roots of wetland plants filter pollutants from water by draining soil

4) High plant growth due to lots of nutrients (soil organic matter, organic carbon) in sediments

5) Support many species of plants and animals, high biodiversity

Dissolved oxygen

Measure of the amount of oxygen gas in water, necessary for organisms' cellular respiration

healthier ecosystem

Higher DO =

stressed ecosystem

Lower DO =

Note: Can create dead zones where no aquatic life can survive

high DO

When flow rate is high-water movement mixes oxygen into water

temperature is low-cooler water holds more DO than warmer water

nutrient pollution is low photosynthesis is high (releases O2)

Oligotrophic

low level of productivity

Mesotrophic

moderate level of productivity

Eutrophic

high level of productivity

Salinity

Abiotic condition - how much salt is in a body of water, determines which species can survive and drinking capability (even in freshwater)

Flow/velocity

Abiotic condition - determines which plants and organisms can survive, how much oxygen can dissolve in water

Temperature

Abiotic condition - warmer water holds less dissolved oxygen, and can support less aquatic organisms

Depth/light

Abiotic condition - influences how much sunlight can penetrate and reach plants below the surface

Nutrients

Abiotic condition - Nutrients-chemicals in water that aquatic plants and animals need to survive

Bottom substrate

abiotic condition - substrate-what makes up the bottom of the body of water

- ex. rocks, mud

Turbidity

Abiotic Condition - measure of suspended particles in water, how cloudy the water is

Rivers

High amounts of oxygen due to running water, carry nutrients (deltas & floodplains = nutrient-rich soil)

Rivers - Threats

1) Dams and Infrastructure - Blocks moving sediment and alturs natural water flow

2) Pollution and Runoff

Lakes

standing bodies of freshwater, key drinking water source

Salinity = >0.5

Lakes - Threats

1) Climate change - rising temps cause increased evaporation, which shrinks water levels

2) Pollution and Eutrophication - Agricultural fertilizers wash into lakes, releasing excess nitrogen and phosphorus

Littoral

1st freshwater stratification - shallow water w/emergent plants (cattails, reeds, roots embedded in soil)

Limnetic

2nd freshwater stratification - where light can reach (photosynthesis!), no rooted plants, only phytoplankton

Profundal

3rd freshwater stratification - too deep for sunlight (no photosynthesis.)

Benthic

4th Freshwater stratification - bottom where invertebrates (bugs) live, nutrient-rich sediments

Intertidal Zone

- Area between high and low tide

- Organisms in an ______ zone live with wave action, drying out due to

tidal action, changing temperature, and changing salinity

- Moderate to high productivity and diversity

- ex. tide pools, crabs, mussels, starfish, sea urchins

Intertidal. - threats

1) Climate Change/Sea Level Rise- Rising temps, increased water acidity, and weather storms stress habitats/organisms

2) Coastal Squeeze - Man made buildings block zones from naturally shifting inland as sea levels rise

Eustaries

- Area where freshwater from rivers and streams mixes with ocean water (brackish water)

- Highly productive and diverse due to nutrients from rivers

- Filters pollutants, reduces flooding, supports fish and aquatic organism breeding

Eustaries - Threats

1) Habitat loss and alteration - large scale conversion w/ draning and filling

2) Pathogens and Nutrient Overload

Coral Reefs

Mutualistic relationship between coral (animals) and algae (plants)

1) Coral take CO2 out of ocean to create calcium carbonate exoskeleton (the reef) & also provide CO2 to the algae

2) Appear in warm, shallow, tropical waters

3) Algae live in the reef & provide sugar (energy) to the coral through photosynthesis

4) Both species rely on the other: (mutualism +/+)

- Coral couldn't survive without energy from algae.

- Algae need the home of the reef & CO2 from the coral

- Extremely high biodiversity and productivity

- Highly sensitive to changes in acidity and temperature, pollution, and overfishing

Coral reefs - Threats

1) Ocean acidification - higher carbon dioxide levels increase acidity in water, so coral cant maintain calcium carbonate skeletons

2) Severe Storms - break apart fragile coral structures

Open Ocean

- Largest biome on Earth

- Generally nutrient-poor and lower productivity than coastal waters

- Although productivity per square meter is low, the ocean contributes a large amount of Earth's total photosynthesis due to size

Open Ocean - Threats

1) Overfishing and Industrial Fishing - deplete fish populations and entangle sharks and turtles

2) Plastic and Chemical pollution - millions of plastic waste break down into microplastics and spread through ocean

Photic zone

upper layer where light reaches, photosynthesis

Aphotic zone

deeper layers where no light reaches