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APES Ch3 Vocab Lytle
Lytle - APES Ch 3 Vocab
Question | Answer |
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average residence time | A measure of the time it takes for a given part of the total pool of a material in a system to be cycled through the system. he ratio of the total size of the pool or reservoir to the average rate of transfer through the pool. |
biosphere | The part of a planet where life exists. A 2nd meaning is: the planetary system that includes and sustains life, and therefore is made up of the atmosphere, oceans, soils, upper bedrock, and all life. |
biota | 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.” |
closed system | A type of system in which there are definite boundaries to factors such as mass & energy such that exchange of these factors w/ other systems does not occur. |
doubling time | The time necessary for a quantity of whatever is being measured to double. |
ecosystem | An ecological community & its local, abiotic community. It's the min. system that includes & sustains life. Must include an autotroph, decomposer, liquid medium, source & sink of energy, & all the chemicals required by the autrophs & decomposers. |
environmental unity | A principle of environmental sciences that states that everything affects everything else, meaning that a particular course of action leads to an entire potential string of events. Another way of stating this idea is that you can’t only do one thing. |
exponential growth | 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. |
feedback | A kind of system response that occurs when output of the system also serves as input leading to changes in the system. |
Gaia hypothesis | The surface environ of Earth, with respect to such factors as the atmospheric composition of reactive gases, the acidity-alkilinity of waters, & the surface temp., are actively regulated by the sensing, growth, metabolism, & other activities of the biota. |
lag time | The time between a stimulus and the response of a system. |
negative 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. |
open system | A type of system in which exchanges of mass or energy occur w/ other systems. |
overshoot and collapse | Occurs when growth in 1 part of a system over time exceed carrying capacity, resulting in sudden decline in one or both parts of the system. |
positive 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. |
steady state | When input equals output in a system, there is no net change and the system is said to be in a steady state. Compare with equilibrium. |
system | 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. |
uniformitarianism | The principle stating that processes that operate today operated in the past. Therefore observations of process today can explain events that occurred in the past and leave evidence, for example in the fossil record or in geologic formation. |