Niagara Falls on the US-Canadian border: well worth seeing.
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Transcript of Niagara Falls on the US-Canadian border: well worth seeing.
Niagara Falls on the US-Canadian border: well worth seeing.
A Terrestrial Aquatic Ecosystem
Human Disruption of Ecosystems
1. Habitat destruction– Tropical rainforests: 20th
century– Illinois prairie: 19th century
• 0.1% remains– Eastern forests, 18th century
• 1 square mile of never-cut forest remains
– Micro-damage• Large Blue butterfly
(Maculinae arion) in England• Song birds in the US?• Amphibians world-wide• Salmon in the Northwest
Human Disruption of Ecosystems
2. Selective destruction of species– Hunting– Fishing
• Examples:• Passenger pigeon • Carolina parakeet
• Doesn’t work with pests– Imported fire ant– Etc, etc, etc
Human Disruption of Ecosystems
3. Importing new species– Perennial pests:
• gypsy moth, Japanese beetle…
– Current villains:• Asian longhorn beetle,
garlic mustard, purple loosestrife, …
– Diseases: • Dutch elm disease• Chestnut blight
– Dogwood anthracnose– Oak wilt …
Burmese python: Everglades
Feral pig damage: Hawaii
Human Disruption of Ecosystems
• Efffects of Chemicals on Ecosystems– Distribution to
• air• soil• water
– Transformation– Uptake by organisms
• Effects on individual organisms• toxicity• persistence• bioaccumulation
– Possible effects on populations• Reproduction• Food• Behaviour
– Possible effects on ecosystems• Alter food web
– Remove predator– Remove prey species
• Alter energy flow
4. Xenobiotics
Xenobiotics
• 4. Xenobiotics– DDT– PCBs– Mercury– Lead– Dieldrin …– Atrazine? – Phthalates?
Xenobiotics and Ecosystems
• Chemical identity– Persistence
• Duration of effects– Bioaccumulation– Number of applications
• Single• Multiple
– Ubiquity of contamination• Ecosystem structure
– Complexity of food webs– Most sensitive species
• Other stresses• Immigration
Operation Cat Drop: A Fable For Our Times
Articles About “Operation Cat Drop”
• O’Shaughnessy, PT, 2008. Parachuting Cats and Crushed Eggs: The Controversy over the use of DDT to control malaria. Am. J Public Health 98:1940–1948.
• On the web:– http://catdrop.com– http://catdrop.com/links.htm– http://the-sieve.com/2013/10/20/operation-cat-drop-history-
or-hoax/
Partial List of Ecologically Harmful Chemicals
• Persistent and bioaccumulative:– DDT and its congeners– Cycodienes
• Aldrin• Dieldrin• Endrin• Heptachlor• Chlordane• Mirex• Chlordecone (Kepone)
– PCBs – PBBs– PFOS & PFOA– Cadmium– Selenium– Organic mercury compounds– Organic tin compounds– Hexachlorobenzene
• Persistent but not bioaccumulative:– Aldicarb– Lead– DES
• Unduly Toxic– Fenthion– Parathion– Compound 1040
• Endocrine disruptors– Vinclozolin– Phthalates– Atrazine?– ….. etc
from Wikipedia:
• The phrase "Better Living Through Chemistry" is a variant of a DuPont advertising slogan, "Better Things for Better Living...Through Chemistry." DuPont adopted it in 1935 and it was their slogan until 1982 when the "Through Chemistry" part was dropped. Since 1999, their slogan has been "The miracles of science".[1]
• The phrase "Better Living Through Chemistry" was used on products that were not affiliated with DuPont to circumvent trademark infringement.[citation needed] This transmutation is now more commonly used than the original. This statement is used for commentary on several different topics, from the promotion of prescription or recreational drugs, to the praise of chemicals and plastics, to the sarcastic criticism of the same.
Water, Earth and Air:
Water Use, Sources of Pollution,
And then ….?
Water, Soil and Air Interconnect
Fields, parking lots,Roofs, roads
bubbles
Wells - private & public
Municipal water sources
Adsorption on solids; Absorption of gases
> 500 feet deep Often communicate with surface
*
Where Illinois gets its water*
Local Issues: Water in Champaign-Urbana
100 million gallons a day (MGD) is pumped 45% consumed by the public, 29% by industry, and 18% by commercial users
Clean Water and Public Health
Clean Water and Public Health:John Snow and the Broad Street Pump
• London, 1849 – cholera epidemic
• John Snow– epidemiology study– preceded Pasteur– Ended epidemic by removing
pump handle
Mapping Cholera Cases to Pump Locations
Clean Water and Public Health
• Water-borne diseases– Cholera– Typhoid– Amoebic dysentery– Giardia– Hepatitis A– Schistosomiasis
• Requires snail vector• Prevent contamination
– Siting of wells relative to • Sewage outflows• Industry
• Types of pollutants– Organic
• Bacteria • Viruses• Protozoans, etc
– Chemicals• Water purification
– Chlorination– Ozonation– Other
• Population density– Affects levels of pathogens
Purifying Water Before Use:Designed to destroy pathogens --
But are there risks?
• Coagulation – Removes solids
• Sedimentation – Removes solids
• Disinfection– Removes pathogens
• Disinfectants– Chlorine or
hypochlorite• trihalomethanes• haloacetic acids
– Chloramine• More stable• Fewer byproducts
– Ozone• Bromate?• No residual
disinfection
Processes for Cleaning Water after Use:also designed to destroy pathogens
• Human & animal waste– Filtration– Biodegradation– A river cleans itself
• Mississippi water is drunk 7x
• Chemical pollution– Pre-World War II
• Organic waste– Biodegradation
• Elemental wastes persist forever– Metals
5x106 T 1985: 100x106 T
Clean Water and Public Health• Consider: Source of water
– Spring– River– Reservoir– Shallow well – Deep well
What Happens When the Water Runs Out?
Summary: Water and Water Pollution
• Case histories of specific pollutants -– Effects of (persistent/bioaccumulative) water pollutants in
ecosystems• How does water become polluted?• Water treatment
– Classical, for pathogens– Other
• Chemicals may be removed by reverse osmosis, etc• Radioisotopes can be removed by aeration
• Where Illinois water comes from– And how that affects pollution
• Running out of (clean, unsalted) water
Water, Air and Soil as Media for Pollutants
Horseshoe Falls: The best views of the falls are from the Canadian side.