In ecology, which Q is a rectangular frame laid on the ground to define an area for study?
Quadrat Quadrat A quadrat is a frame, traditionally square, used in ecology and geography to isolate a standard unit of area for study of the distribution of an item over a large area. Modern quadrats can for example be rectangular, circular, or irregular. The quadrat is suitable for sampling plants, slow-moving animals, and some aquatic organisms. The systematic use of quadrats was developed by the pioneering plant ecologists R. Pound and F. E. Clements between 1898 and 1900. The method was then swiftly applied for many purposes in ecology, such as the study of plant succession. Botanists and ecologists such as
Momentum–depth relationship in a rectangular channel to the bottom of the channel (Figure 1). The average pressure can be obtained from the integral of the pressure distribution: Where: Applying the continuity equation: For the case of rectangular channels (i.e. constant width “b”) the flow rate, Q, can be replaced by the unit discharge q, where q = Q/b, which yields: And therefore: By dividing the left and right side of the momentum-force equation by the channel’s width, and substituting the above relationships: Dividing through by ρg: Start with the conservation of momentum function formula_14, for rectangular channels: Where: Isolate the q terms on one side of