1.13 Pollutants in Ecosystems

(Sec 5.2 pg 113 – 117)VIDEO (Crash Course – Pollution)

http://www.youtube.com/watch?v=kdDSRRCKMiI

• Healthy ecosystems exist in a dynamic (changing) equilibrium (balance) – the abiotic and biotic components tend to be kept in a ‘balance’ through complex interactions in the system.

• Sometimes, factors are introduced that upset the balance of an ecosystem.

• Pollutants are defined as substances introduced into the air, water, soil or food in concentrations that threaten the health or survival of organisms, and can seriously upset the natural balance in ecosystems.

• They’re classified by the part of the environment they affect...

• Pollutants are classified by the part of the environment they affect:– Air pollutants = anything that changes the quality or

properties of air. – Some examples include: acid precipitation (‘acid rain’ –

see p.114), greenhouse gas emissions, ground-level ozone (adds to smog), etc. (see & understand Table 1 p.114)

• Pollutants are classified by the part of the environment they affect:– Water pollution = air pollution often ends up dissolved

in water (e.g. acid rain). Also, any pollutants spilled on land often end up in rivers, lakes and/or the ocean due to runoff.

– Examples include; organic waste (e.g. feces) – depletes oxygen in H2O, dangerous solvents that build-up and poison the food chain, hot water that raises the temperature of rivers & lakes killing fish, etc. (see and understand Table 3 p.116)

• Pollutants are classified by the part of the environment they affect:– Land pollution = anything that uses up land space

and/or harms an ecosystem. – May include: hazardous wastes like batteries that leak

acid, radioactive waste that can cause cancers, etc. (see and understand Table 4 p.117)