Marine Biomes & Water Pollution

first half of unit 7

Freshwater biomes

Biomes with low salt concentration, including lakes, rivers, and wetlands.

Saltwater (Marine) biomes

Biomes with high salt concentration, including oceans and estuaries.

What determines the categorization/type of biome?

salinity, temperature, and amount of sunlight

Salt concentration of Marine Biome

3%

Salt concentration of Freshwater Biome

0.1%

Earth coverage of Marine Biome

97% of Earth’s surface

Earth coverage of Freshwater Biome

<3% of Earth’s water supply

Estuary

A transitional area where freshwater from rivers meets saltwater from the ocean (Mixing of fresh and salt water bc of tides)

Intertidal Zones

Areas where land meets the sea, characterized by fluctuating water levels and exposure to air.

Organism adaptations to Intertidal Zones

1. tolerances to varying water levels & air exposure

2. ability to attach to substrates

3. ex: urchins, sea stars, anemones

Primary Productivity

The rate at which sunlight is converted into organic compounds via photosynthesis.

Net Primary Productivity

The remaining glucose (organic matter) available for use after accounting for cellular respiration in an ecosystem

Net Primary Productivity Formula

Net Primary Productivity = Gross Primary Productivity - Cellular Respiration

Euphotic Zone

The upper part of the ocean where sunlight penetrates (up to 200m deep)

Euphotic Zone Importance

it is home to phytoplankton and controls populations of other organisms

Thermoclines

thin layer where temperature changes rapidly

Thermoclines effect

can restrict nutrient flow

Ocean’s Role In Global Productivity

1. almost half of global photosynthesis occurs in oceans

2. phytoplankton are key players

Euphotic Zone

part of ocean where sunlight penetrates (200m deep)

Importance of Euphotic Zone

home to phytoplankton, controls populations of other organisms

Factors that Affect Ocean Productivity

1. thermoclines

2. upwelling

3. nutrient availability

4. sunlight

Climate Change Impact

1. increased temperatures in Southern Ocean

2. greater thermoclines reduce nutrient upwelling

3. potential increase in ocean “desert” areas

Water pollution categorization by source

1. point source pollution

2. non-point source pollution

Water Pollution categorization by composition

1. nutrient pollution

2. thermal pollution

3. sediment pollution

4. biological pollution

5. chemical pollution

effect of nutrient pollution

1. causes oxygen sag curve

2. affects dissolved osygen (DO) levels and biodiversity

effect of thermal pollution

decreases DO levels (power plants, urban runoff)

effect of sediment pollution

1. reduces light penetration

2. disrupts benthic habits

effects of biological pollution

1. caused by pathogens (bacteria, viruses)

2. major human health concern, especially in developing countries

effects of chemical pollution

1. can affect both surface and groundwater

2. pesticides, heavy metals, petroleum

Persistent Organic Pollutants (POPs)

do not easily break down in environment

effects of POPs

1. bioaccumulations

2. biomagnification

Bioaccumulation

absorption into fatty animal tissue

Biomagnification

concentration increases up the food chain

bioassays

test to determine effects of chemical/Pollutants on living organisms (LD50 or Lethal Dose 50%)

wetlands characteristics

1. water present at least part of the year

2. hydric (wet) soils

3. hydrophytic vegetations

wetland importance

1. water retention

2. erosion reduction

3. pollutant filtration

4. carbon sequestration

Carbon sequestration in wetlands

1. anoxic soils slow decomposition of organic matter

2. vegetation fixed atmospheric carbon through photosynthesis

wetland disturbance result

releases stored carbon due to increased decomposition

wetland protection

creating, enlarging, or preserving wetlands to offset human impacts

1. productivity distribution: open ocean

   1. 65% of Earth) = low productivity

   2. algal beds and coral reefs (0.1% of Earth’s surface): highest marine productivity