Terms for organisms of different trophic levels in terrestrial ecosystems
Producers - Autotrophic organisms that make their own food via photosynthesis
Consumers - Heterotrophic organisms that eat the producers
Herbivores - Animals that eat plants; primary consumers
Omnivores - Animals that eat plants or animals; can be primary or secondary consumers
Carnivores - Animals that eat other animals; secondary consumers or tertiary consumers
Decomposers - Organisms that are involved in recycling nutrients back into the ecosystem; insects, scavengers, bacteria, fungi, other microorganisms
Humans as the ultimate consumer
Earth's ecosystems cannot sustain the current levels of economic activity and material consumption
- Current rates of resource harvesting & waste generation exceed natural regeneration rates
- Defined as the area of ecologically productive land and water in various classes (cropland, pastures, forests and other natural ecosystems) that would be required on a continuous basis to provide all the energy and material resources consumed, and to absorb all the wastes discharged by a population with prevailing technologies. (Wckernagel & Rees 1996 - Our Ecological Footprint)
- assumes that every category of energy & material consumption + waste discharge needs a certain amount of productive and absorptive capacity of a finite are of the planet
What is Ohio's Ecological Footprint?
Ohio has a population of about 11.5 million
11.5 million X 5.1 ha (the American EF) = 58,650,000 ha
Ohio has an area of 10,717,700 ha
It's about 5 times bigger than the state!!!!
Why do I need to know this stuff? It's so depressing!
Knowing our circumstances is an invitation to change
- The environment is not something "out there" -- we're part of it
- The current environmental crisis is more of a behavioral and social problem than a problem with technology and development
- Understanding ecological constraints can help in developing strategies for sustainable economies
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Last updated January 29, 1999.