4.4 Water Pollution Flashcards
Ex situ
Latin for Off site
Opposite of in situ
In situ
Latin for On Site
Opposite of ex situ
Concentrate vs dissipate
To increase the amount (stormwater concentrates pollution) vs to decrease the amount (wetlands work to dissipate pollutants)
Pollution
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.
Acute Pollution
Stems from a single output/event, often with singular impact
Chronic Pollution
Occurs over a wide area, and long period of time.
Difficult to identify source, and difficult to manage.
Point source pollution
Discharges from a single outlet (such as a pipe). Traceable to a single source.
Non-point source pollution
Many sources/origin points. Normally contained within runoff.
Difficult to assign responsibility. Difficult to manage.
Organic Pollution
“Organic” typically means carbon-based. Includes things like oils as well as biological material, such as leaves.
POP
Persistent organic pollution/pollutant. “Persistent” means it doesn’t readily breakdown (or biodegrade)
Anthropogenic pollution
As opposed to “natural pollution” is pollution attributable to the actions of humans
Secondary Pollution
(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.
Outfall
the place where a river, drain, or sewer empties into the sea, a river, or a lake.
Discharge
Pollution being released into the environment. Can refer to a quantity or a process.
Functions of a wetland
- Dissipation of flow energy (flood control)
- Storage (containment) of water
- Filtering of pollutants
- Settling of sediment
- Aeration
- Habitat value
Nitrates
Contained within fertilizer and manure. Often in farm runoff. Is a nutrient for plant growth, so often contributes to algal blooms.
Phosphates
A nutrient pollutant the sources of which include fertilizers and detergents.
Heavy metals
Toxic metals (mercury, lead, cadmium, arsenic) - often as ions. Can accumulate in systems and impact health.
Source from mines and industrial activities.
Suspended pollutants
Not soluble. Held in suspension in the water column.
Fine sediment.
Can settle (sink) in still water.
Pesticides
Include insecticides.
Sprayed on crops to prevent insect infestation.
Famously includes DDT (a persistent pollutant)
Herbicides
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.
Gross Pollutant Trap
“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.
Riparian buffer
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.
Rain gardens
Collect road runoff and allows storage and infiltration of deposited water before entering water courses.
Pollution Management Model
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.
Aeration
Important aspect of aquatic environments. Provides opportunity for water to become oxygenated. Oxygen is used by aquatic organisms.
Sedimentation
Settling of sediment. Occurs in still watter, when sediment falls out of suspension.
Dredging
clear the bed of (a harbour, river, or wetland) by scooping out mud, weeds, and rubbish with a dredge.
Eutrophication
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.
Algae
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
Anoxic conditions
the absence of oxygen (used in the context of eutrophication)
BOD
Biochemical Oxygen Demand: the amount of dissolved oxygen that organisms need to break down organic materials in water
Algal bloom
A proliferation of algae (often covering the surface of a body of water). Brought about by high temperatures and nutrient excess.
Aerobic
In the presence of oxygen.
Used in the context of aerobic respiration, which produces energy from food in the presence of oxygen.
Anaerobic
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.
Decomposition
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.
Water column
a vertical expanse of water stretching between the surface and the floor of a body of water.
Turbidity
In water, the quality of being cloudy, opaque, or thick with suspended matter (sediment)
Dead Zone
areas of water bodies where aquatic life cannot survive because of low oxygen levels
Red tide
a discoloration of seawater caused by a bloom of toxic red algae
Cyanobacteria
Also called blue-green algae, are essentially autotrophic (photosynthesizing) aquatic bacteria.
As opposed to algae, which is a plant.
Aerator
Technocentric solution to improve dissolved oxygen in water. A simple fountain is enough o agitate the srface.to allow the diffusion of oxygen
Agitate
When water passes over rapids or encounters obstacles or is roughened. Allows for aeration - diffusion of oxygen
Slurry
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.
Sewage
Wastewater and excrement conveyed in sewers
Wastewater
Used water.
What we put down the drain.
Effluent
liquid waste or sewage discharged into a river or the sea.
Hypoxic/Hypoxia
Oxygen delivery is insufficient to meet the metabolic needs of an organism.
Distinct from anoxic/anoxia, which is the complete absence/lack of oxygen.
What processes consume oxygen in an aquatic ecosystem?
Respiration
Decomposition
Two ways oxygen can get into an aquatic system:
Photosynthesis of aquatic plants.
Diffusion from the atmosphere.
Limiting Factor (for production)
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.
DDT
A biomagnifying POP pesticide, banned in many countries for its impact on the environment.
