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Barry Commoner\'s Four Laws of Ecology, as written in The Closing Circle in 1971.

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Barry Commoner\'s Four Laws of Ecology, as written in The Closing Circle in 1971. . 1. Everything is Connected to Everything Else . There is one ecosphere for all living organisms and what affects one, affects all.

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slide1

Barry Commoner\'s Four Laws of Ecology, as written in The Closing Circle in 1971.

1. Everything is Connected to Everything Else. There is one ecosphere for all living organisms and what affects one, affects all.

Consider- let’s remove the gray wolf from the Lamar Valley of the Greater Yellowstone Ecosystem….

Wait! We already did that in the 1800-1900’s!

slide2

Okay fine, now what did the gray wolf normally eatin this ecosystem?

X

X

X

Human?

Cow?

Ok, a few

Sheep?

Once in a while

Elk

American Bison?

Yah Baby!

Moose?

slide3

Okay, so what do Elk eat?

Vegetation such as Aspen

or Willow

When the wolves were removed would you expect the number of Elk to increase or decrease?

Duh!

If the number of Elk increased, what would you expect to happen to the Aspen and Willow abundance?

slide4

Freshly sprouted willow branches, healthy and un-browsed by elk

A 1992 study in northern Yellowstone found that elk reduced potential willow seed production by 100% and that 47% of the willow communities had been height suppressed.

Wolves were re-introduced into the area starting in 1995

slide5

Photo taken 7/17/1997

Decadent (dying) Aspen in the northern Greater Yellowstone Ecosystem (northern range). All trees are 100-130 years old. No new growth since the root sprouts (ramets) have been completely eaten by Elk. (Page 66 in Yellowstone’s destabilized ecosystem by Frederic H. Wagner)

slide6

Over browsed Aspen stand being replaced by sagebrush and related species (Photo from the Northwest Habitat Institute.)

slide7

Aspen stands provide food or cover for literally hundreds (thousands) of other species, many of which have declining populations. For example,

Red-naped Sapsucker

MacGillivray’s Warbler

Yellow Warbler

CalliopeHummingbird

Additional information about bird declines due to lack of wolf predation on large herbivores J. Berger, et al, 2001. Ecological Applications 11(4):947-960

slide8

Back to willow- For the sake of discussion, does anything else eat willow plants?

Beavers!

So if the amount of available willow decreases, what would you expect to happen to the beaver population?

slide9

Do Beaver have any effect on the environment? Does anything depend on the Beaver?

So what was once a fast moving stream, is now a pond containing an entirely new ecosystem and supporting bank vegetation and creating flooded valleys which effect the water table.

slide10

Barry Commoner\'s Four Laws of Ecology, as written in The Closing Circle in 1971.

2. Everything Must Go Somewhere. There is no "waste" in nature and there is no “away” to which things can be thrown.

If willow and aspen communities are removed due to over browsing by Elk or Moose etc, and the beaver depart because of the lack of food/cover, can you predict what might happen to the stream banks and water table of the resulting ecosystem?

slide11

Can you predict what kind of species would be able to use this ecosystem?

What do you suppose would happen if land managers tried to re-introduce beaver into this system?

slide12

Barry Commoner\'s Four Laws of Ecology, as written in The Closing Circle in 1971.

3. Nature Knows Best. Humankind has fashioned technology to improve upon nature, but such change in a natural system is “likely to be detrimental to that system.”

So, what the heck, let’s just put the wolves back into the Greater Yellowstone Ecosystem?

Hmmmmmm…… now there’san idea……. Stay tuned.

slide13

Barry Commoner\'s Four Laws of Ecology, as written in The Closing Circle in 1971.

4. There Is No Such Thing as a Free Lunch. In nature, both sides of the equation must balance, for every gainthere is a cost, and all debts are eventually paid.

slide14

West Virginia mountain forest view, original photograph by Jim Clark, Mountain Memories, Vandalia Press 2003

slide15

A massive dragline, dwarfed by the huge scale of the operation, at work on a mountaintop removal surface mine operation near Kayford Mountain, West Virginia. Photo by Vivian Stockman, Oct. 19, 2003

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