Abiotic: not biological; especially, not involving or produced by organisms (Merriam-Webster, 2001).

Alluvial Fans: A low, outspread, relatively flat to gently sloping mass of loose rock material, shaped like
an open fan or a segment of a cone, deposited by a stream (esp. in a semiarid region) at the place where it issues from a narrow mountain valley upon a plain or broad valley (Bates and Jackson, 1980).

Alluvium: A general term for all deposits resulting directly or indirectly from the sediment transport of streams deposited in riverbeds, flood plains, lakes, fans, and estuaries (Zedaker, 1998).

Annual: A species with a life cycle of 12 months or less (Begon et al.,1990).

Aquatic: Growing or living in or frequenting water; taking place in or on water (Warner and Hendrix, 1984).

Anthropogenic: Of human origin (Zedaker, 1998). Aquifer: A water-bearing stratum of permeable rock,
sand, or gravel (Merriam-Webster, 2001).

Arroyo: A water-carved gully or channel (Merriam- Webster, 2001).

Aspect: The direction towards which a slope faces; the seasonal appearance of a community, e.g. the spring aspect (Zedaker, 1998).

Bank: The portion of the channel cross section that restricts lateral movement of water at normal levels.
The bank often has a gradient steeper than 45 degrees and exhibits a distinct break in slope from the stream bottom (American Fisheries Society, 1985).

Bentonite: A soft plastic light-colored clay formed by chemical alteration of volcanic ash (Bates and Jackson, 1984).

Biennial: A species with a life cycle of approximately 2 years with fruiting occurring in the second year
(Zedaker, 1998).

Bio-complexity: A descriptive and as yet immeasurable condition or phenomenon encompassing the components and interdependent linkages among biotic and abiotic elements in a system.

Biodiversity: An index of species richness in a community and the relative abundance of these species; high biodiversity is achieved by high species richness and equal relative abundance (Zedaker, 1998).

Biodiversity: Refers to the variety and variability among living organisms and the ecological complexes in which they occur. Diversity can be defined as the number of different items and their relative frequencies. For biological diversity, these items are organized at many levels, ranging from complete ecosystems to the
biochemical structures that are the molecular basis of heredity. Thus, the term encompasses different ecosystems, species, and genes (EPA, 1998).

Biotic: Of living organisms and their ecological rather than physiological relations (Zedaker, 1998).

Canopy: The overhead or dominant trees in a forest; the overhead branches and leaves of streamside vegetation (Zedaker, 1998).

Channel: A natural or artificial waterway of perceptible extent that periodically or continuously contains moving water, having a definite bed and banks which serve to confine the water (Zedaker, 1998).

Channelization: The practice of straightening a waterway to remove meanders and make water flow faster. Sometimes concrete is used to line the sides and bottom of the channel.

Community: An association of living organisms having mutual relationships among themselves and their environment and thus functioning, at least to some degree, as an ecological unit (Warner and
Hendrix, 1984).

Creek: A small stream of water which serves as the natural drainage course for a drainage basin of nominal or small size (Zedaker, 1998).

Drainage: The manner by which the waters of an area flow off in surface streams or subsurface conduits (Bates and Jackson, 1984).

Diurnal: a) Active chiefly in the daytime; b) Recurring every day (Merriam-Webster, 2001).

Diversity: The variety and variability of all life forms, all plants, animals and micro-organisms, the genes they contain and the ecosystems they form.

Dominance: Refers to those plant species whose removal would result in the greatest impact on soils, climate, and biotic features of the ecosystem. Usually this is evidenced in the size, frequency, coverage, and
or distribution of a species (Holland and Keil, 1995).

Down-cutting (Incision): Cut down into, as a river cuts
into a flood plain terrace.