4.4 Water Pollution

Question 1

Ex situ

Answer 1

Latin for Off site

Opposite of in situ

Question 2

In situ

Answer 2

Latin for On Site

Opposite of ex situ

Question 3

Concentrate vs dissipate

Answer 3

To increase the amount (stormwater concentrates pollution) vs to decrease the amount (wetlands work to dissipate pollutants)

Question 4

Pollution

Answer 4

the addition of a substance or an agent to an environment by human activity at a rate greater than that at which it can be rendered harmless by the environment, and which has an appreciable effect on the organisms within it.

In other words…the contamination of air, water, or soil by substances that are harmful to living organisms.

Question 5

Acute Pollution

Answer 5

Stems from a single output/event, often with singular impact

Question 6

Chronic Pollution

Answer 6

Occurs over a wide area, and long period of time.
Difficult to identify source, and difficult to manage.

Question 7

Point source pollution

Answer 7

Discharges from a single outlet (such as a pipe). Traceable to a single source.

Question 8

Non-point source pollution

Answer 8

Many sources/origin points. Normally contained within runoff.
Difficult to assign responsibility. Difficult to manage.

Question 9

Organic Pollution

Answer 9

“Organic” typically means carbon-based. Includes things like oils as well as biological material, such as leaves.

Question 10

POP

Answer 10

Persistent organic pollution/pollutant. “Persistent” means it doesn’t readily breakdown (or biodegrade)

Question 11

Anthropogenic pollution

Answer 11

As opposed to “natural pollution” is pollution attributable to the actions of humans

Question 12

Secondary Pollution

Answer 12

(As opposed to primary pollution which is nasty the moment it is discharged) is benign when it enters the environment, but undergoes a transformation (chemical change), which makes it more potent/volatile/impactful.

Question 13

Outfall

Answer 13

the place where a river, drain, or sewer empties into the sea, a river, or a lake.

Question 14

Discharge

Answer 14

Pollution being released into the environment. Can refer to a quantity or a process.

Question 15

Functions of a wetland

Answer 15

• Dissipation of flow energy (flood control)
• Storage (containment) of water
• Filtering of pollutants
• Settling of sediment
• Aeration
• Habitat value

Question 16

Nitrates

Answer 16

Contained within fertilizer and manure. Often in farm runoff. Is a nutrient for plant growth, so often contributes to algal blooms.

Question 17

Phosphates

Answer 17

A nutrient pollutant the sources of which include fertilizers and detergents.

Question 18

Heavy metals

Answer 18

Toxic metals (mercury, lead, cadmium, arsenic) - often as ions. Can accumulate in systems and impact health.
Source from mines and industrial activities.

Question 19

Suspended pollutants

Answer 19

Not soluble. Held in suspension in the water column.
Fine sediment.
Can settle (sink) in still water.

Question 20

Pesticides

Answer 20

Include insecticides.
Sprayed on crops to prevent insect infestation.
Famously includes DDT (a persistent pollutant)

Question 21

Herbicides

Answer 21

Sprayed on plants (weeds) to kill them.
Glyphosate (also known by the product name Round-up) is a well known non-selective one (which means it kills non-discriminately). It breaks down (biodegrades) in soil (it is not a POP!), but you don’t want it washing into waterways while it does so (fish and aquatic organisms) are also killed.

Question 22

Gross Pollutant Trap

Answer 22

“Gross” means “big” in German, right?
A gross pollutant trap is one of those big nets or grates you see over a drain that traps big waste, like water bottles, plastic bags and big sticks and branches. It stops these materials from clogging up or contaminating the system downstream.

Question 23

Riparian buffer

Answer 23

Planting trees/shrubs/grass on and adjacent river banks to trap and store polluting agents before they make their way into water catchments during runoff events.

Question 24

Rain gardens

Answer 24

Collect road runoff and allows storage and infiltration of deposited water before entering water courses.

Question 25

Pollution Management Model

Answer 25

Three steps/approaches to pollution management.
1. Modify the polluting behaviour (manufacture/creation of pollutants)
2. Regulate/control the release of pollutants into the environment.
3. Clean up and rehabilitate impacted environments.

Question 26

Aeration

Answer 26

Important aspect of aquatic environments. Provides opportunity for water to become oxygenated. Oxygen is used by aquatic organisms.

Question 27

Sedimentation

Answer 27

Settling of sediment. Occurs in still watter, when sediment falls out of suspension.

Question 28

Dredging

Answer 28

clear the bed of (a harbour, river, or wetland) by scooping out mud, weeds, and rubbish with a dredge.

Question 29

Eutrophication

Answer 29

When a body of water becomes enriched in dissolved nutrients that stimulate the growth of aquatic plant life, usually resulting in the depletion of dissolved oxygen.

Question 30

Algae

Answer 30

a simple, non-flowering, and typically aquatic plant of a large group that includes the seaweeds and many single-celled forms. Algae contain chlorophyll but lack true stems, roots, leaves, and vascular tissue….so often float on the surface

Question 31

Anoxic conditions

Answer 31

the absence of oxygen (used in the context of eutrophication)

Question 32

BOD

Answer 32

Biochemical Oxygen Demand: the amount of dissolved oxygen that organisms need to break down organic materials in water

Question 32

Algal bloom

Answer 32

A proliferation of algae (often covering the surface of a body of water). Brought about by high temperatures and nutrient excess.

Question 32

Aerobic

Answer 32

In the presence of oxygen.
Used in the context of aerobic respiration, which produces energy from food in the presence of oxygen.

Question 33

Anaerobic

Answer 33

In the absence of oxygen.
Used in the context of anaerobic respiration, in which some organisms can produce energy through respiration in the absence of oxygen. Usually produces toxic or bad smelling byproducts.

Question 34

Decomposition

Answer 34

The breaking down or decay of something. When organic materials decompose, they use oxygen, so in an aquatic system this can reduce the amount of dissolved oxygen.

Question 35

Water column

Answer 35

a vertical expanse of water stretching between the surface and the floor of a body of water.

Question 36

Turbidity

Answer 36

In water, the quality of being cloudy, opaque, or thick with suspended matter (sediment)

Question 37

Dead Zone

Answer 37

areas of water bodies where aquatic life cannot survive because of low oxygen levels

Question 38

Red tide

Answer 38

a discoloration of seawater caused by a bloom of toxic red algae

Question 39

Cyanobacteria

Answer 39

Also called blue-green algae, are essentially autotrophic (photosynthesizing) aquatic bacteria.
As opposed to algae, which is a plant.

Question 40

Aerator

Answer 40

Technocentric solution to improve dissolved oxygen in water. A simple fountain is enough o agitate the srface.to allow the diffusion of oxygen

Question 41

Agitate

Answer 41

When water passes over rapids or encounters obstacles or is roughened. Allows for aeration - diffusion of oxygen

Question 42

Slurry

Answer 42

Semi-liquid, made of suspended solids in water. Can have the consistency of a paste.
Farm slurry is a mixture of cow manure, mud and water.

Question 43

Sewage

Answer 43

Wastewater and excrement conveyed in sewers

Question 44

Wastewater

Answer 44

Used water.
What we put down the drain.

Question 45

Effluent

Answer 45

liquid waste or sewage discharged into a river or the sea.

Question 46

Hypoxic/Hypoxia

Answer 46

Oxygen delivery is insufficient to meet the metabolic needs of an organism.

Distinct from anoxic/anoxia, which is the complete absence/lack of oxygen.

Question 47

What processes consume oxygen in an aquatic ecosystem?

Answer 47

Respiration
Decomposition

Question 48

Two ways oxygen can get into an aquatic system:

Answer 48

Photosynthesis of aquatic plants.
Diffusion from the atmosphere.

Question 49

Limiting Factor (for production)

Answer 49

A plant can only grow as fast as the required resource in the lowest amount/quantity. This resource is the “limiting factor”. In the case of primary production during eutrophication, oxygen is the limiting factor.

Question 50

DDT

Answer 50

A biomagnifying POP pesticide, banned in many countries for its impact on the environment.