Stress , Environmental

Acute An exposure to an environmental stress that is brief in relation to the temporal scale of the biological system exposed. Biosphere All the plants and animals on Earth, together with the habitat they need for long-term survival. Biotic impoverishment The decline of a species to the point of having little or no ecological significance. Chronic An exposure to an environmental stress that is comparable in duration to the temporal scale of the biological system exposed. Ecosystem services The structures and functions of natural biological systems which directly or indirectly support human life. Environmental stress An action, agent, or condition that impairs the structure or function of a biological system. Function The performance of a biological system as a rate. Structure The number, kinds, and arrangement of component parts at one point in time. Tipping point When a complex system goes into disequilibrium and is replaced by a new system in evolutionary time. Uncertainty Imperfect knowledge concerning the current or future state of a system under consideration; a component of risk resulting from imperfect knowledge of the degree of hazard or of its spatial and temporal pattern of expression.