APES Unit 8

point source

Pollutant that is easily identified and in a confined place

You can point to it

nonpoint source

Pollutants entering the environment from many places at once

Difficult to “point” to one individual source

point source examples

• Animal waste runoff from a CAFO

• Emissions from smokestack

• Oil Spill

nonpoint source examples

• Urban runoff (motor oil, nitrate fertilizer, road salt, sediment)

• Pesticides sprayed on fields; carried by wind and washed off large agricultural regions into bodies of water

range of tolerance components and physiological effects

abiotic conditions:

• pH

• temperature

• salinity (saltiness)

• sunlight

• nutrient levels (ammonia, phosphate)

physiological stress that pollutants cause

• Limited growth

• Limited reproductive function

• Difficulty respiring → potentially asphyxiation (suffocation)

• Hormonal disruption

• Death

environmental effects of acid rain

pH tolerance

• As pH decreases (more acidic) outside optimal range for a species, pop. declines

indicator species

can be surveyed and used to determine conditions of an ecosystem

coral reef and photosynthetic algae relationship

mutualistic

what does algae supply

sugar and pigment

what does coral reef supply

CO₂ and organic matter

what happens to coral reef and algae when temperatures rise? what are the effects for the coral? what is something else that forces algae away from coal?

algae has a narrow temperature tolerance and leaves the coral when temp rises, so coral loses color and looks bleached → stressed and vulnerable to disease w/out algae (main food source)

pollutants from runoff (sediment, pesticides, sunscreen) can force algae away from coral

Human impacts on coral reef

• greenhouse gas emissions

  • warming ocean temps

  • bleaching coral

• overfishing

  • decrease fish populations

• bottom trawling

  • break reef structure

  • stir up sediments

• sediment pollution

  • caused by runoff

  • reduces sunlight

• toxicants

  • chemicals in sunscreen

  • oil from roadways

  • pesticides from ag. runoff

• nutrients

  • ammonia from animal waste

  • nitrates/phosphates from fertilizers

oil spill effects

• toxic to marine organisms, especially if they eat/absorb oil

  • decreased visibility

  • decreased photosynthesis

  • oil sticking to bird feathers

  • oil sinking to bottom and killing bottom-dwellers

    • direct toxicity or suffocation

• decrease fish revenue

  • hurt restaurants that serve fish

• decrease tourism revenue

  • isn’t aesthetically pleasing

oil spill clean up

• try to contain oil spill

• vacuum

• physical removal of oil from beach sand and rocks with towels, soaps, shovels

• get it to sink to the bottom

• burn oil off the surface

Describe two effects that an oil spill can have on marine organisms

Sinks to bottom and kills bottom-dwellers (toxicity or suffocation)

Decreases photosynthesis due to less sunlight

Identify specific pollutants that disrupts coral reef ecosystems

Phosphate and nitrogen from agricultural or land fertilizers can damage coral reef system

Endocrine Disruptors

Chemicals that interfere with the endocrine (hormonal) systems of animals by blocking or mimicking the hormone via cellular receptors

• can amplify or block hormone’s effects

• caused by urine or flushing meds into sewers

Atrazine (endocrine disruptor)

herbicide used to control weeds & prevent crop loss

• Applied to ag. fields → runs off into local surface or groundwater or carried by wind

• Can contaminate human well-water

DDT (endocrine disruptor)

insecticide (phased out → still persists in env.)

• Applied to ag. fields, runs off into local surface or groundwater or is carried by wind

Phthalates (endocrine disruptor)

compounds used in plastic and cosmetic manufacturing → skin absorbs chemicals

what are 3 endocrine disruptors that are heavy metals?

lead, arsenic, and mercury

Lead source, effects, and mitigation

source: old paint in homes, old water pipes, soil contaminated by PM from vehicle gas

effects: neurotoxicant, endocrine disruptor

mitigation: water filters

Coal ash

source of mercury, lead, and arsenic

• carried by wind and deposited in ecosystems far away w/ PM

• can leach into groundwater and nearby surface waters

• can be caused by ash left behind from campfire

what are non lethal effects that endocrine disruptors can have

altered reproductive development and reduced fertility

toxic form of mercury

methylmercury

teratogen

chemical harming a pregnant woman’s baby

• birth defects