4.4 Water Pollution

Question 1

Pollution

Answer 1

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 2

Acute Pollution

Answer 2

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

Eg Bhopal disaster

As opposed to chronic pollution.

Question 3

Chronic Pollution

Answer 3

Occurs over a wide area, and long period of time.

Difficult to identify source, and difficult to manage.

As opposed to acute pollution

Question 4

Point Source Pollution

Answer 4

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

Question 5

Non Point Source Pollution

Answer 5

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

Question 6

Organic pollution

Answer 6

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

Question 7

Hydrocarbons

Answer 7

An organic compound, consisting of chains of carbon, hydrogen and oxygen atoms.

Eg Petrol, Oil, Diesel, Alcohol, Natural Gas

Question 8

POP

Answer 8

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

Eg DDT

Question 9

Anthropogenic pollution

Answer 9

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

Question 10

Secondary Pollution

Answer 10

(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 10

Primary Pollution

Answer 10

Straight from the source (as discharged)

Question 11

Natural pollution

Answer 11

Organic matter (leaves), sediment, volcanic gases etc.

Question 12

Outfall

Answer 12

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

Question 13

Discharge

Answer 13

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

Question 14

Nitrates

Answer 14

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

Question 15

Phosphates

Answer 15

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

Question 16

Heavy metals

Answer 16

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

Question 17

Suspended pollutants

Answer 17

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

Question 18

Pesticides

Answer 18

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

Question 19

Herbicides

Answer 19

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 20

DDT

Answer 20

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

Question 21

Biomagnification

Answer 21

The concentration of toxic substances increases at each successive level of the food chain.

substances accumulate in tissues because they are not easily broken down or excreted. As a result, higher trophic levels (e.g., predators) tend to have higher concentrations.

Not to be confused with bioaccumulation

Question 22

Bioaccumulation

Answer 22

the gradual accumulation of substances, such as pesticides or other chemicals, in an organism’s tissue.

Not to be confused with biomagnification

Question 23

In situ vs Ex situ

Answer 23

Latin for on site and off site.

Eg. Water is far better off being stored in situ (where it lands) than running off and being stored ex situ.

Question 24

Concentrate vs dissipate

Answer 24

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

Question 25

5 ways a wetland can be used to manage water pollution.

Answer 25

1. filtering water 2. absorption and assimilation of nutrients 3. trapping or settling of sediment 4. UV treatment of microbes 5. water storage (flood dissipation)

Question 26

Gross pollutant trap

Answer 26

"Gross" means "big" in German. 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 27

Riparian buffer

Answer 27

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 28

Rain gardens

Answer 28

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

Question 29

Pollution Management Model

Answer 29

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 30

Aeration

Answer 30

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

Question 31

Sedimentation

Answer 31

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

Question 32

Dredging

Answer 32

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

Question 33

Eutrophication

Answer 33

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 34

Algal bloom

Answer 34

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

Question 35

Algae

Answer 35

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 36

BOD

Answer 36

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

Question 37

Anoxic Conditions

Answer 37

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

Question 38

Aerobic

Answer 38

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

Question 39

Anaerobic

Answer 39

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 40

Decomposition

Answer 40

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 41

Water column

Answer 41

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

Question 42

Turbidity

Answer 42

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

Question 43

Dead Zone

Answer 43

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

Question 44

Red Tide

Answer 44

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

Question 45

Aerator

Answer 45

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

Question 46

Cyanobacteria

Answer 46

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

Question 47

Agitate

Answer 47

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

Question 48

Slurry

Answer 48

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 49

Sewage

Answer 49

Wastewater and excrement conveyed in sewers

Question 50

Wastewater

Answer 50

Used water. What we put down the drain.

Question 51

Effluent

Answer 51

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

Question 52

Hypoxic/Hypoxia

Answer 52

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 53

What processes consume oxygen in an aquatic ecosystem?

Answer 53

Respiration Decomposition

Question 54

Two ways oxygen can get into an aquatic system

Answer 54

Photosynthesis of aquatic plants. Diffusion from the atmosphere.

Question 55

Limiting factor

Answer 55

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 56

Hydrocarbon Spill Management

Answer 56

Containment Booms Skimmers and Vacuums Absorbents Chemical Dispersants Combustion Bioremediation

Question 57

Bioremediation

Answer 57

using living organisms, such as bacteria, fungi, or plants, to degrade (breakdown) or detoxify environmental contaminants

Question 58

Hydrocarbon

Answer 58

an organic compound consisting primarily of hydrogen and carbon atoms. Eg. Oil, gas, petrol, diesel, methane, ethanol