All the individuals of a species that occupy a particular geographic area at a certain time.
For example, the population of humans in Elkhorn at the time the photo was taken was 4082.
Accelerating growth that produces a J-shaped curve when the population is graphed against time.
Though humans are not the best choice because we do not have a equilibrium yet, this graph does show the exponential growth of humans after the industrial revolution and major scientific and medical advances.
A factor that limits the growth, distribution, or amount of a population in a ecosystem.
Examples of limiting factors include food, water, space, and shelter.
The size of a population that can be supported indefinitely by the available resources and services of an ecosystem.
The way in which an organism occupies a position in an ecosystem, including all the nessasary biotic and abiotic factors.
An organism that kills and consumes other organisms.
For example, a lynx is a predator to a snowshoe hare.
An organism that is eaten as food by a predator.
For example, an insect is prey to baby crocodiles and many other predators.
A symbiotic relationship between two species in which both species benefit from the relationship.
For example, photosynthesis algae lives inside coral and provides the coral with nutrient while it receives protection and a constant supply of carbon dioxide for photosynthesis.
An organism whose niche is dependent on a close association with a larger host organism.
For example, a brainworm and a deer.
When two or more organisms compete for the same resource in the same location at the same time.
Use that does not lead to long-term depletion of a resource or affect the diversity of the ecosystem from which the resource is obtained.
Sustainable use of a resource, whether it is water or an entire ecosystem, allows the resource to meet the needs of present and future generations.
The period of time that is required for a population to double in size.
The current doubling time for humans (for when the textbook was written) is 60 years.
A measure of the impact of an individual or a population on the enviorment in terms of energy consumption, land use, and waste production.
A pattern or activity that leads to a decline in the function of an ecosystem.
Use of Earth's resources, including land and water, at levels that can continue forever.
The benefits experienced by organisms, including humans, that are provided by sustainable ecosystems.
provision of food and clean water
pollination of crops and vegetation
conversion of atmospheric carbon into biomass
beauty and spirituallity
cycling of nutrients
The change of non-desert land into a desert, which may result from climate change or from unsustainable farming or water use.
A form of tourism that is sensitive to the heath of an ecosystem and involves recreational activities provided by sustainable ecosystems.