Management of Salt-Affected Soils - Practices of Irrigation and On-farm Water Management - page 291

makers to design and target programs specific to the extent and the nature of the
problem.
Salinity mapping assists in

• targeting salinity control activities

•

focusing on the areas with the best opportunity for cost-effective control

•

creating a database with saline areas specified by the legal land location

• generating the color-coded salinity maps from the database

• calculating the areas affected by each salinity type

• applications at the provincial and farm levels

• creating regional and provincial salinity maps and database

• monitoring changes in salinity from provincial to farm level

• targeting provincial soil salinity control programs

The salinity databases have a number of applications. Most importantly, the munic-
ipality can use the information to target its salinity control programs. Because
the information is in digital format, it is simple to calculate statistics on the
areas affected by the different salinity types. These statistics allow the munici-
pality to focus on those saline areas which can be easily controlled with low-cost
methods.

8.3.4.2 Salinity Classification

The classification is helpful in salinity control programs because the cause of the
salinity determines which control practice is appropriate. Salinity may be classified
based on hydrogeology, surface water flow, geology, topography, and soils:

A: Classification based on causes/sources of salinity
B: Classification based on the development mode
C: Classification based on salt content or EC

A: Classification Based on Causes/Sources of Salinity

There are two different kinds of salinity visible around the world:

1. Groundwater fed salinity or Seasonal salinity
2. Saline soil or Permanent salinity

Groundwater Fed Salinity or Seasonal Salinity

In this category, salinity is groundwater fed with the rising and lowering of ground-
water. This happens mainly in low-rainfall area (dry area) and to seasonally dry
soil, caused by capillary rise of saline shallow underground water. Example is: the
eastern part of North Dakota, USA, which become saline in the dry part of the year.