1. Variation in the physical characteristics of ecosystems across a landscape caused by variation in soil, slope, aspect, elevation, climate, and geology, and the accompanying variation in biotic communities. Also known as ecological or biological diversity.
1. The anticipated outcome of a scientific experiment according to the research hypothesis.
2. In the scientific method, the expected result is the outcome of the experiment if the research hypothesis is true.
The process used to test research hypotheses in the scientific method. In order to be useful in scientific inquiry, an experiment should be objective, with reliable and verifiable data. In addition, the results of the experiment must be reproducible by other scientists.
A flood wall, also known as a levee or dike, is a natural or man-made flood-control structure usually consisting of a wall or mound of earth (sometimes rock or stone) running generally parallel to a river or other drainage channel, or along ocean frontage. Flood walls help to contain floods within the channel by raising the height of the riverbank, thereby allowing the channel to hold a greater volume of water
before flooding begins. Flood walls are also used to protect low-lying land near the ocean that has been reclaimed by pumping and dredging and developed, as in the coastal areas of Louisiana (United States) or the Netherlands.
The study of the forces, processes, events, and actions that are responsible for shaping the Earth's surface. Of these forces, moving water at or near the soil surface (including surface runoff, overland flow, and interflow) has by far the greatest influence on surface alteration of the Earth.
Terms, Definitions, and Concepts: Geology, Hydrology, Science, Water
Describes the solar energy-driven process by which water moves and is distributed on the earth's surface; includes as major components precipitation, evaporation, transpiration, infiltration, surface runoff, and groundwater flows.
The area that immediately underlies a riverbed, varying in depth depending on geologic structure, composition, and the size of the river bottom. Organisms can be quite plentiful in this zone, at times even more abundant than those inhabiting the river bottom itself, with oxygen being the limiting factor.
Terms, Definitions, and Concepts: Biology, Ecology, Geology, Hydrology, Science, Water
An explanation for natural or other phenomena, developed using abductive reasoning following observation (the scientific method). The hypothesis is tested through the use of designed experiments, and shown to be either valid or invalid. If the original research hypothesis is deemed invalid, a new hypothesis must be developed, often based on further ovservation as well as the results from the previous experiment(s).
The process by which precipitation seeps into sub-surface layers of the soil; some is held as soil moisture recharge, some resurfaces as streamflow, and the remainder becomes part of groundwater flows (aquifers).
Also known as Percolation.
Terms, Definitions, and Concepts: Ecology, Forestry and Silviculture, Hydrology, Science, Water
Definition: An inland body of water, generally of considerable size, that collects and stores usually fresh water from surface runoff, and where there is little or no horizontal movement of the impounded water. Lakes can be formed by volcanic, human, or glacial activity; by mass wasting such as landslides; or by stream channel abandonment such as may occur with old, meandering rivers (an "oxbow" lake).
Terms, Definitions, and Concepts: Ecology, Geography, Geology, Hydrology, Real Estate, Science, Water
The activities, operations, or purposes that are employed in a particualr geographic area; the specific manner in which a parcel or tract of land is utilized. Land use is usually regulated by municipal governments through zoning ordinances, although some land uses are regulated by state or federal governments.
A levee, also known as a dike or flood-wall, is a natural or man-made flood-control structure usually consisting of a wall or mound of earth (sometimes rock or stone) running generally parallel to a river or other drainage channel, or along ocean frontage. Levees help to contain floods within the channel by raising the height of the riverbank, thereby allowing the channel to hold a greater volume of water
before flooding begins. Levees are also used to protect low-lying land near the ocean that has been reclaimed by pumping and dredging then developed, as in the coastal areas of Louisiana (United States).