Land and Watershed Management - Practices of Irrigation and On-farm Water Management - page 227

Several process-based models have been developed to predict runoff volume and
sediment yield from watershed.
6.5.8.1 SWAT
“SWAT” stands for “Soil and Water Assessment Tool.” SWAT is a continuous-time
model developed at the USDA-ARS to predict the impact of land management prac-
tices on water, and sediment yields in large (basin scale) complex watersheds with
varying soils, land use and management conditions over long periods of time (> 1
year). SWAT provides large-scale assessment of the status of surface water hydrol-
ogy in the watershed and is useful for ungauged watersheds, and watersheds with
limited data.
6.5.8.2 KINEROS
“KINEROS” stands for “Kinematic Runoff and Erosion Model.” KINEROS is a
physically based model designed to simulate runoff and erosion from single storm
events in small watersheds less than about 100 km 2 .
6.5.8.3 AGWA
“AGWA” stands for “Automated Geospatial Watershed Assessment Tool.” AGWA
is a GIS (Geographic Information System)-based hydrologic modeling tool that is
designed for performing relative assessments (change analysis) resulting from land
cover/use change (Burns et al. 2005).
6.5.8.4 RUSLE2
RUSLE2 is Revised Universal Soil Loss Equation (USDA-ARS). RUSLE2 includes
several components. One major RUSLE2 component is the computer program that
solves the many mathematical equations used by RUSLE2. A very important part of
the RUSLE2 computer program is its interface that connects the user to RUSLE2.
Another major component of RUSLE2 is its database, which is a large collec-
tion of input data values. The user selects entries from the database to describe
site-specific field conditions. The other major component of RUSLE2 is the mathe-
matical equations, scientific knowledge, and technical judgment on which RUSLE2
is scientifically based.
6.6 Watershed Management
6.6.1 Problem Identification
As human populations expand, and demands upon natural resources increase, the
need to manage the environments in which people live becomes not only more