|WORLD METEOROLOGICAL ORGANIZATION||
|Explanation of the criteria for classification and numbering of components|| L30.3.02
|Explanation of the dates on the component's description|
SALTMOD: PREDICTING DEPTH TO WATERTABLE AND SOIL SALINITY
1. Purpose and objectives
The expansion of large scale irrigation systems in the world has
caused wide spread waterlogging and salinity, which threatens the
sustainability of irrigated agriculture. Installation of vertical or
SALTMOD uses equations of seasonal water and salt balances and is not
based on traditional equations to describe flow of water and transport of
salt through aquifers and soils. As a result the predictions are seasonal estimates. This gives SALTMOD the character of an expert system,
which can make long term predictions of depth to water table and soil salinity for a defined area. In flat land a typical area covered by SALTMOD
is in the order of 10,000 ha. In undulating land the area is smaller.
The input requirements are less and more readily available than those of models using the traditional equations describing flow and transport of salt through aquifers and soils. Input data is the components of seasonal water balances related to surface hydrology such as rainfall, runoff, evaporation, irrigation and drain water reuse and related to aquifer hydrology such as upward seepage, natural drainage and water pumped from wells. Initial values of depth to water table and salinities of irrigation water and soil should be given as well as some soil and aquifer
characteristics. SALTMOD works with menus to assist the user with input
Output data is remaining components of the water balance such as downward percolation, upward capillary rise, gravity drainage and resulting depth to watertable and soil salinity.
5. Operational requirements and restrictions
Minimum requirement for application of SALTMOD is a 360 kB RAM PC.
6. Form of presentation
The program is available on diskette with a draft user manual. ILRI is working on a new version of this manual which will be issued in the ILRI
7. Operational experience
SALTMOD has been developed, tested and adjusted over the past ten years. It has been successfully used in Portugal, Egypt and India.
Application in Pakistan and China is in progress.
8. Originator and technical support
International Institute for Land Reclamation and Improvement ILRI
Through the HOMS National Reference Centre for The Netherlands or directly from ILRI.
10. Conditions of use
Current versions of program and manual are available from ILRI at no cost on condition that (1) the user acknowledges ILRI in any publication of work conducted with SALTMOD and (2) the users shares its experiences with ILRI.
|(First entered: 31 JULY 01||
Last updated: 19 JAN 98)