Chapter 5 Biodiversity and Conservation. "For if one link in nature's chain might be lost, another might be lost, until the whole of things will vanish by piecemeal." - Thomas Jefferson
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Chapter 5 Biodiversity and Conservation
"For if one link in nature's chain might be lost, another might be lost, until the whole of things will vanish by piecemeal."- Thomas Jefferson
"We consider species to be like a brick in the foundation of a building. You can probably lose one or two or a dozen bricks and still have a standing house. But by the time you've lost 20 per cent of species, you're going to destabilize the entire structure. That's the way ecosystems work."- Donald Falk, Christian Science Monitor, 26 May 1989
Dodo bird, Mauritius, extinct by 1681.
Passenger Pigeon, N.America, last one died in 1914 in the Cincinnati zoo.
A monument to the passenger pigeon in a Wisconsin State Park declares: "This species became extinct through the avarice and thoughtlessness of man.“
Passenger pigeons laid only one egg per nesting…
C – D.Lambert
Moa, extinct around 1800 in New Zealand
Habitat Degradation: damage to habitat due to pollution.
Air, water, or land.
Air: breathing problems, irritating membranes, acid rain damaging soil, trees, changes lake pH. Burning of fossil fuels is chief cause.
Ozone damage. O3 protects earth like sunscreen. Extremely vulnerable to oxidizers like chlorofluorocarbons (CFCs). Breakdown results in skin cancer and amphibian worldwide declines.
Water: industrial, animal waste, fertilizers, silt on coral reefs. Fertilizers often result in large algal blooms in water, die, decay, remove all oxygen. Results in loss of species and fish deaths. (This is common in our area).
Land: landfills, pesticides, chemicals. DDT (banned in U.S.) actually relatively nontoxic to humans in small amounts, but does not break down and accumulates in tissue. Thus passed higher and higher up food chain, concentrated.
Introduction of exotics: new species introduced to environment. Can be deliberate (bringing in a new garden plant or bug to control a weed) or accidental (sea lampreys making it into Great Lakes via canals). Exotic species are not native to a particular area. They can grow exponentially (no competition/predators) and take over niches, prey on native species, destroying them.