SALTIRSOIL_M: an application to predict monthly soil salinity in irrigated well-drained lands

 

SALTIRSOIL_M (SALTs in IRrigated SOILs Monthly assessment) is a computer program developed to calculate the ionic composition and electrical conductivity of saline, calcareous and gypsiferous soil solutions in the mid to long term in irrigated well-drained lands. SALTIRSOIL_M uses weather, soil, crop, irrigation water quality and irrigation management data. From the information of rainfall, evapotranspiration, irrigation management and crop and soil properties SALTIRSOIL_M carries out a monthly water balance. From this balance it calculates a concentration factor of the soil solution regarding the irrigation water for each of the months of the year. The major ion composition of the irrigation water is multiplied by this factor to obtain the ion concentration of a solution far from equilibrium. This composition is used as input for the module SALSOLCHEM integrated into SALTIRSOIL_M, which calculates the composition of the soil solution in equilibrium with calcite and gypsum minerals at the apparent partial pressure of CO2 in the soil. SALTIRSOIL_M is written in Microsoft Visual Basic 2005 ©. The data needed to perform the simulations of soil salinity are stored in a database in Microsoft Access© distributed together with the application, and in which the user can enter new data or modify existing ones according to the simulations he/she wants to perform. The simulations are batch run.

The essential steps for running the SALTIRSOIL_M model are described below.

SALTIRSOIL_M is copyrighted software by the author, distributed free for research, management and educational purposes and downloadable here.

The SALTIRSOIL_M model has featured several research articles which can be accessed from this page.

Thumbnail Image 1

Data base

All data needed to carry out the simulations are in the database SALTIRSOIL_m.mdb. In the "Batch_Clim" and "Weather_Stations" tables is the information on climate, in the "Batch_Soil" table is the information on soil, and in the 'Batch_Wat' table is the information on irrigation water quality. In the "Batch_Tree_Crops_Growth" and "Annual_Crops_Growth" tables is the information on crop development and management of multiannual and annual crops, respectively. Similarly in the "Batch_Tree_Crops_Irrigat" and "Annual_Crops_Irrigat" tables is the information on irrigation management of multiannual and annual crops, respectively. There are also three tables for the thermodynamic constants, ion parameters, and coefficients to calculate the EC25. These eleven tables contain the essential information to perform the simulations with SALTIRSOIL_M.

Thumbnail Image 1

Crop parameters

The do the simulations with annual crops and crop rotations we have to complete the data in the tables 'Batch_Annual_Crops_Growth' and 'Batch_Annual_Crops_Irrigat' from the data in the tables 'Annual_Crops_Growth' and 'Annual_Crops_Irrigat', respectively. This is carried out by means of this tool, which is accessed through the the "Tools" menu. In the dropdown list "Crop" we select one of the annual crops. The crop coefficients and length in days of each of the development stages of the selected crop are shown in the box "Crop parameters". In the dropdown list "Length / days" the total crop length is shown according to the information in the database. Unfolding the list we can select another length for our crop. Then we select the planting date of our crop. The calculations must be saved clicking on the "Annotate" button.

Thumbnail Image 1

Reference evapotranspiration

The absence of reference evapotranspiration data makes necessary their obtention from climate basic data. This can be accomplished by using this tool of the SALTIRSOIL_M model. It is accessed in the "Tools" menu by clicking in the submenu "Reference evapotranspiration". Then the dialog box "Calculation of reference evapotranspiration" is open. In this box we select the weather station from the dropdown list. When one weather station is selected the corresponding monthly average temperature and rainfall data are graphed in the climogram below. Simultaneously the options to calculate the reference evapotranspiration are activated according to the data requirements of each method and the data availability in the station. The methods available are "Thornthwaite", "FAO's Penman-Monteith", "Hargreaves", and "Blaney-Criddle". Provided we have our own ET0 measurements they can be also used by selecting "Default Data".

Thumbnail Image 1

Batch setup

To do the simulations the 'Batch_' tables have to be ready. Then we select "Batch Data" from the "Simulations" menu to open the dialog box "Batch setup". To setup a new simulation scenario the soil, irrigation water quality, climate, the crop or crop rotation, and the irrigation schedule are selected from the corresponding dropdown lists. Other data needed to carry out the simulations are then selected such as a method to assess the soil water contents, and the soil solutions for which the composition will be assessed. Every time we have a different combination of the input data, we have a different simulation scenario. The scenarios can be added to the simulation batch by clicking on the "Add" button, thereby appearing in the bottom grid. When we have a set of scenarios, we can save them in the database by clicking on the "Save Input Table" button. We will be able to recover this scenarios for simulating them later by clicking on the "Load Input Table" button.

Let's get started with SALTIRSOIL_M following these four steps:

              1. Click on the button below and and save the compressed zip file in your computer.
              2. Extract and save its content, which includes the user's manual and SALTIRSOIL_M.mdb, within your computer.
              3. Install the program by clicking on the setup.exe file.
              4. Follow the instructions.

download

Related publications:

  1. Soil, Water and Crop Management for Agricultural Profitability and Natural Resources Protection in Salt-Threatened Irrigated Lands (2012). In: Problems, Perspectives and Challenges of Agricultural Water Management, Chp. 15, pp. 293-310. Intech. ISBN 978-953-51-0117-8. Full text
  2. Irrigation recommendation in a semi-arid drip-irrigated artichoke orchard using a one-dimensional monthly transient-state model (2014). Agricultural Water Management 138, pp. 26-36. doi:10.1016/j.agwat.2014.02.019