Lecture 6 - Pollutants Intro

Question 1

Difference btw pollution, environmental stressors, and disturbance

Answer 1

Pollution: Exposure to chemicals or energy at an intensity that exceeds the tolerance of organisms
- different from contamination, which is when potentially damaging stressors are present at intensities too low to cause damage
- all pollutants are contaminants, but not all contaminants are pollutants
- can be natural or anthropogenic

Disturbance: Episodic, but intense influence that causes severe biological and ecological damage

Environmental stressor: factors that constrain productivity, reproductive success, and ecological development

Question 2

Natural vs. anthropogenic sources

Answer 2

Pollutants can be natural or anthropogenic
- ex natural. volcanoes

Question 3

Main types of pollution (with examples)

Answer 3

1. Chemical
   - when 1 or more substances occur in concentrations high enough to prompt negative physiological responses in organisms, potentially causing toxicity and/or ecological change
   - ex. sulfur dioxide, metals, pesticides, petroleum
2. Thermal
   - when the release of heat into the enviro results in ecological stress, due to variations in species tolerance of temp extremes
   - ex. hot sea vents, power plants
3. Biological
   - when humans release organisms beyond their natural range
   - ex. invasive species, pathogens
4. Sensory (noise + light)
   - when the level of ambient sound becomes distracting to the normal activities of humans or are detrimental to wildlife; when artificial light levels are detrimental to wildlife
5. Aesthetic
   - ex. visual images, displeasing enviros

Question 4

Secondary pollution

Answer 4

The release of substances that react in the environment, to synthesize chemicals of greater toxicity