enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Drainage density - Wikipedia

    en.wikipedia.org/wiki/Drainage_density

    According to the equations, a basin with high drainage density, the contribution of surface runoff to stream discharge will be high, while that from baseflow will be low. Conversely, a stream in a low drainage density system will have a larger contribution from baseflow and a smaller contribution from overland flow. [8] [9]

  3. Drainage equation - Wikipedia

    en.wikipedia.org/wiki/Drainage_equation

    A drainage equation is an equation describing the relation between depth and spacing of parallel subsurface drains, depth of the watertable, depth and hydraulic conductivity of the soils. It is used in drainage design. Parameters in Hooghoudt's drainage equation. A well known steady-state drainage

  4. Runoff model (reservoir) - Wikipedia

    en.wikipedia.org/wiki/Runoff_model_(reservoir)

    The discharge may also be expressed as: Q = − dS/dT . Substituting herein the expression of Q in equation (1) gives the differential equation dS/dT = A·S, of which the solution is: S = exp(− A·t) . Replacing herein S by Q/A according to equation (1), it is obtained that: Q = A exp(− A·t) .

  5. Runoff curve number - Wikipedia

    en.wikipedia.org/wiki/Runoff_curve_number

    As can be seen in the curve number equation, runoff cannot begin until the initial abstraction has been met. It is important to note that the curve number methodology is an event-based calculation, and should not be used for a single annual rainfall value, as this will incorrectly miss the effects of antecedent moisture and the necessity of an ...

  6. Groundwater flow equation - Wikipedia

    en.wikipedia.org/wiki/Groundwater_flow_equation

    The above groundwater flow equations are valid for three dimensional flow. In unconfined aquifers, the solution to the 3D form of the equation is complicated by the presence of a free surface water table boundary condition: in addition to solving for the spatial distribution of heads, the location of this surface is also an unknown. This is a ...

  7. Stream power law - Wikipedia

    en.wikipedia.org/wiki/Stream_power_law

    The term stream power law describes a semi-empirical family of equations used to predict the rate of erosion of a river into its bed. These combine equations describing conservation of water mass and momentum in streams with relations for channel hydraulic geometry (width-discharge scaling) and basin hydrology (discharge-area scaling) and an assumed dependency of erosion rate on either unit ...

  8. Universal Soil Loss Equation - Wikipedia

    en.wikipedia.org/wiki/Universal_Soil_Loss_Equation

    The Universal Soil Loss Equation (USLE) is a widely used mathematical model that describes soil erosion processes. [1]Erosion models play critical roles in soil and water resource conservation and nonpoint source pollution assessments, including: sediment load assessment and inventory, conservation planning and design for sediment control, and for the advancement of scientific understanding.

  9. Playfair's law - Wikipedia

    en.wikipedia.org/wiki/Playfair's_Law

    By modeling Playfair's law in the following mathematical scheme, we can find the incision rate of the stream into the valley by following: ˙ = [1] where