4.4 - WATER POLLUTION Flashcards
What are types of pollutants that affect water systems?
Plastic waste, nets, microplastics.
Runoff from fields, sewage, Solid domestic waste.
How is water quality controlled?
Collection of samples followed by analytical tests (pH, temp, turbidity, presence of metals). Considered polluted if chemical concentrations are high.
How can biological materials pollute water?
If natural components infest water, they can deplete it of its oxygen and create anoxic conditions (eutrophication)
What is biochemical oxygen demand?
the amount of dissolved oxygen that must be present in water in order for microorganisms to decompose the organic matter
Why is cold water more tolerant to fluctuating oxygen levels?
Because it holds more oxygen than warm water.
What is a biotic index?
Measurement used to assess the quality of an environment by indicating the types of organisms living in it.
Indicator species
Species that by their presence or absence can indicate water pollution
How does eutrophication affect water?
Increased turbidity, loss in dissolved oxygen, increase in primary productivity –> algal bloom, loss in species diversity.
How can eutrophication be reduced?
using fertilizing alternatives, phosphate-free detergents, advanced sewage treatment processes. Cleanup and species restoration.
