GLOSSARY abiotic: the nonliving elements of an ecosystem. Example: rocks, water abiotic factors: see ‘abiotic’ adaptation: a process over multiple generations in which an organism changes to better fit the habitat Example: Natural selection would favor the deeper-rooted plants during climate shifts that cause drought conditions arid: land or climate that receives limited precipitation (rain or snow) biodiversity: every living organism within a single ecosystem or habitat, including numbers and diversity of species biotic: living elements of an ecosystem. Example: soil bacteria, plants, predators biotic factors: see ‘biotic’ census: a complete population count cienega: alkaline, freshwater, spongy, wet meadows with shallow-gradient, permanently saturated soils in otherwise arid landscapes that often occupied nearly the entire widths of valley bottoms. They are usually associated with seeps or springs, found in canyon headwaters or along margins of streams. competition: Occurs due to limited resources, which prevents equal access and supply, as organisms compete for survival. Competition can occur between organisms of the same species or between members of different species. conservation: the preservation and protection of natural resources through sustainable practices to prevent loss of habitats and biodiversity cover: the area that plants take up when viewed from a bird’s-eye perspective ecological restoration (restoration): the process of repairing sites in nature whose biological communities and ecosystems have been degraded or destroyed ecosystem services: the benefits humans obtain from ecosystems. Examples: food and water, flood and disease control, nutrient cycling ecosystem: an interacting system of biotic and abiotic elements linked together through nutrient cycles and energy flows endangered Species: organisms whose number have reduced drastically and if not conserved could become extinct erosion: the process by which the surface of the earth is worn away by the action of water, glaciers, winds, waves, etc. geology: the study of the earth’s physical structure and substance, history, and the processes that act on it groundwater: water held underground in the soil or in pores and crevices in rock. habitat: The area or natural environment in which an organism or population normally lives herbivory: the consumption of plant material by animals hydrology: the study of water, and especially its movement in relation to land invasive species: an introduced organism that becomes overpopulated and negatively alters its new environment. Although there may be beneficial aspects, invasive species adversely affect the invaded habitats, causing ecological, environmental, and/or economic damage.
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