13-24 Human Impacts on Ecosystems

APES 2024

Human impacts on ecosystems

Human impacts on ecosystems

• Some countries dump their waste in the ocean

• Has led to plastic pollution

• Large floating islands of plastic have resulted

• Great Pacific Garbage Patch

• Wildlife can become entangled in the waste and ingest it

Coral reefs have been suffering damage due to

• Increasing ocean temperature

• Sediment runoff

• Destructive fishing practices

Corals are particularly sensitive to global warming because

their range of temperature tolerance is quite small

An increase of just 1° Celsius can lead to

coral bleaching

Coral bleaching

when stressed corals release their mutualistic algae which provide the corals with energy, loss of algae causes the coral to turn white

• an be temporary but if it lasts for a while the coral will die

Causes of coral bleaching

warming oceans, pollution and sedimentation

Humans are converting salt water to fresh water through desalination or desalinization

Process through distillation and reverse osmosis

Distillation

water is boiled and steam is captured and condensed back into water

Reverse osmosis

water is forced through a semipermeable membrane at high pressure, water goes through but salt does not

Brine

Leftover liquid has a very high salt concentration can cause harm if dumped

Oil pollution

Petroleum products are highly toxic to many marine organisms, including birds, mammals, and fish, as well as to the algae and microorganisms that form the base of the aquatic food chain

Oil on the surface can

coat feathers of birds and fur on marine mammals

Some oil can sink to ocean floor and

kill bottom dwelling organisms

Oil that washes up on the beach can lead to

decrease in money for fishing and tourism industries

Sources of oil in the ocean

natural seeps, extraction of oil from underneath the ocean, transport of oil by tanker or pipeline, and consumption of petroleum-based product

Ways to remediate oil pollution

• Containment: Booms keep the floating oil from spreading, then boats equipped with giant oil vacuums suck up as much oil as possible
  • Chemicals: Chemicals break up the oil on the surface, making it disperse before it hits the shoreline
  • Bacteria: A particular bacterium consumes oil; scientists are currently trying to genetically engineer the bacterium to consume oil even faster

Wetland

areas where water covers the soil either all or part of the time

Ecological services

water purification, flood protection, water filtration and habitat for organisms

Threats to wetlands

Nitrogen and phosphorous, sediment, motor oil, pesticides, endocrine disruptors, developments, overfishing, and water diversion for flood control, agriculture and drinking water

Development

draining wetland to build

Mangrove forest

along tropical and subtropical coasts, tree roots are submerged in water (salt tolerant)

Mangrove Services

Stabilize coastline and protect shorelines

Mangrove threats

commercial development, dam construction, overfishing, pollutants from agriculture and industrial waste

Litter

• Can be unsightly

• Can create intestinal blockage and choking hazards for wildlife

• Introduce toxic substances into the food chain

• Ex. Plastic straws and plastic

Increased sediment in waterways can

reduce light infiltartion

30% of all sediments in our waterways comes from

natural sources while 70% comes from human activities

Problems with sedimentation

• Suspension of soil particles cause waterways to become brown and cloudy

• Reduced infiltration of sunlight lowers productivity of aquatic plants and algae

• Sediments clog gills and prevent aquatic organisms from obtaining oxygen