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Chapter 3 Terms
APES Chapter 3 Terms
Question | Answer |
---|---|
a kind of system that occurs when output of the system also serves as input leading to changes in the system | feedback |
a type of feedback that occurs when the system's response is in the opposite direction of the output. Thus negative feedback is self-regulating | negative feedback |
a type of feedback that occurs when an increase in output leads to a further increase in output. This is sometimes known as a vicious cycle, since the more you have, the more you get. | positive feedback |
a type of system in which exchanges of mass or energy occur with other systems | open system |
occurs when growth in one part of a system over time exceeds carrying capacity, resulting in a sudden decline in one or both parts of the system. | overshoot and collapse |
when input equals output in a system, there is no net change and the system is said to be in a steady state. A bathtub with water flowing in and out at the same rate maintains the same water level and is in a steay state. | steady state |
a set of components that are linked and interact to produce a whole. For example, the river as a system is composed of sediment, water, bank, vegetation, fish, and other living things that all together produce the river. | system |
the principle stating that processes that operate today operated in the past. Therefore, observations that occurred in teh past and leave evidence, for example, in the fossil record or in geologic formations. | uniformitarianism |
a measure of the time it takes for a given part of the total pool or reservoir of a particular material in a system to be cycled through the system. ART is the ratio of the total size of the pool to the average rate of transfer through the pool. | average residence time ART |
That part of a planet where life exists. On Earth it extends from the depths of the oceans to the summits of mountains, but most exist within a few meters of the surface. | biosphere |
all the organisms of all species living in an area or region up to and including the biosphere, as in "the biota of the Mojave Desert" or "the biota in that aquarium." | biota |
a system in which there are definite boundaries to mass and energy and thus exchange of these factors with other systems does not occur. | closed system |
the time necessary for a quantity of whatever is being measured to double | doubling time |
An ecological community and its local, nonbiological community. The minimum system that includes and sustains life. It must have at least an autotroph, a decomposer, a liquid medium, a source and sink of energy, and all required chemical element. | ecosystem |
A principle of environmental sciences that states that everything affects everything else, meaning that a particular course of action could lead to a string of events. You can't do only one thing! | environmental unity |
Growth in which the rate of increase is a constant percentage of the current size; that is, the growth occurs at a constant rate per time period. | exponential growth |