NATS1512 FINAL EXAM Flashcards
Worldwide, how many people do not have access to an improved water source?
780 million
What is Water Pollution?
The contamination of bodies of water (eg. lakes, river) where pollutants are directly or indirectly discharged into them without adequate treatment
What is a point source? Provide an example.
Pollution that is a discharged from a single source/ point (eg. sewage, industrial, oil, mining)
What is a non-point source? Provide an example.
Pollution that is discharged from many sources rather than a single specific site (eg. road salt, animal waste, agriculture runoff, precipitation)
Is it harder to control pollution from a point source or a non point source? Why?
Non - point pollution is more difficult to control because it comes from multiple locations
What is a reservoir?
A location where water is stored
Major water reservoirs and percentages?
Ocean (96.5%)
Freshwater (2.5%)
What is the process that transports water TO the atmosphere?
Evaporation - as the sun heats up water (eg. in the ocean) it changes from a liquid to a gas
Sublimation - ice and snow can sublimate directly into water vapour
Evapotranspiration - evaporated water specifically from plants and soil
What is the process that transports water FROM the atmosphere?
water vapour in the atmosphere cools and condenses into clouds
Precipitation: if cloud particles grow large enough, they can fall out of the sky as precipitation (as either, snow, rain, hail etc)
Deposition - transfer of water vapour directly to solid water (ice/ snow)
What is the process that transports water ALONG the Earths surface?
Surface Runoff: precipitation flows over the ground until it ends up in a river/ stream because of gravity and then flows into a lake/ ocean eventually
Infiltration - precipitation can lead into the groundwater and eventually recharge into a lake/ ocean because of gravity
What are the 6 conventional water pollutants that are often present in large amounts and can have serious effects?
1 Biochemical Oxygen Demand (BOD)
2 Nutrients (eg. Nitrogen N)
3 Suspended soils
4 pH
5 Oil and Grease
6 Pathogenic microorganisms
Talk about case location: Baltic Sea (Case location for BOD and Nutrients)
95% of Baltic Sea is assessed as being eutrophied
Over 85 million people live within the Baltic Sea catchment area
Nutrients such as Nitrogen (N) and Phosphorus (P) are naturally occurring in our environment but excessive inputs of N and P into water systems is a direct result of _____
human activities
What are the primary sources of nutrient pollutions?
- Runoff of fertilizers from agricultural fields
- Animal manure
- Sewage and wastewater
- Laundry detergents and soap
Excess N and P in a water system can also lead to _____ ____?
cultural eutrophication
what is cultural eutrophication?
The process of nutrient enrichment and subsequent ecosystem degradation
What is the cultural eutrophication process?
- Nutrient input into a water system
- Algae at the surface of the water system feed on nutrients and flourish and block sunlight from entering ecosystem
- Eventually algae die and drift to the bottom of the water system, providing food for decomposers
- As decomposers breakdown algae, they remove oxygen from the water which limits the amount available for fish and plants (increased BOD)
- With a hypoxic zone created, most fish and plants die
What is BOD (Biochemical Oxygen Demand)
Amount of oxygen required to decompose a given amount of organic material. High BOD reduces or depletes dissolved oxygen in water. Fish that are mobile can move away from hypoxic (low oxygen) zones but sedentary organisms may die
True or false: prior to human existence on earth, eutrophication of aquatic ecosystems did not occur
False
What are some of the impacts of an aquatic ecosystem becoming eutrophied?
Aquatic - loss/ changes of biodiversity
Economic - loss in fishers/ tourism
Human - bloom of algae and phytoplankton can release toxins into the water or be toxic themselves
Suspended Soils (SS) is the most….
common pollutant in rivers, streams, lakes and reservoirs
What are some impacts of Suspended Soils (SS)
Human - can give drinking water drinking and odor problems
Economic - Sediment causes potentials of flooding in homes and sediment increases the cost of treating drinking water
Aquatic - Murky water prevents photosynthesis and vegetation from growing in water
Sediment pollution in water leads to a number of impacts on coral locations (case location: Australia) like…
- Injury to coal tissue
- Reduced photosynthetic efficiency (from shading caused by sediment)
- Change in coral colour arising from changes in the density of photosynthetic pigments (coral bleaching!)
Talk about Little Rock Lake, Wisconsin USA (case location for pH)
Northern half of Little Rock Lake was part of a research experiment to investigate the impacts of pH on aquatic systems. After 6 years of acidification, everything in the lake died (1984 - 1990)
What is pH?
A scale of acidity from 0 - 14
Acidic solutions have a pH less than…
7
Basic/ Alkine solutions have a pH greater than….
7
Neutral solutions have an exact pH of…
7
A lake that is NOT affected by human activity has a pH of…
6 - 7
Effects of pH levels
7…
6…
5….
4.5-5…
4
7: Neutral pH, optimal conditions
6: snails and crayfish begin to die
5: fish eggs do not hatch, some fish begin to die
4.5 - 5: Fish species begin to die (like bass)
4: Flies/ frogs begin to die
What is the indirect impact of pH?
Aluminum stress: high concentrations of Aluminum in water bodies can cause stress on fish species causing higher rates of mortality
Case Location: Nova Scotia (Oil and Grease)
There are both natural and anthropogenic sources of oil to aquatic ecosystems:
Natural: Marine Seeps (200 known significant marine seeps)
Anthropogenic: Platforms (more than 8,000 offshore platforms globally) and Atmospheric deposition, Pipeline Spills
What is Oil?
Complex substance composed of thousands of different kinds of organic molecules
What are the 2 toxic effects of Oil?
Oiling - Organisms most affected by oiling are aquatic birds, particularly auks, penguins and diving sea ducks because they spend most of their lives on the surface of the sea
Disruption of Function -
Direct toxic effects include:
- Development
* Reproduction
Sublethal effects include:
* Disruption to energetic processes
* Interference with biosynthetic processes
* Structural development
Impacts of oil and grease on aquatic plants?
Oil spills block the sunlight that is required for plants to photosynthesize, kills plants growing in water