2. Reclamation of salt- affected soils
Munwar Sultana Solangi
Lady Instructor
Agriculture Training Institute
Sakrand

3. Soil
An agricultural definition of soil is "a dynamic natural body on the surface of the earth in which plants grow, composed of mineral and organic materials and living forms"

4. Types of soil

5. Salt- Affected soils
The soils contain excessive amounts of either soluble salts or exchangeable sodium or both.

6. Nature of salt- affected soils
Saline soils:
Soils containing sufficient amount of soluble salts to interfere with germination and growth of most crop plants are classified as saline.

7. Sodic soils
Soils containing sufficient exchangeable sodium to adversely affect their properties and plant growth.

8. Soils containing both soluble salts and exchangeable sodium
Saline- sodic soils
Soils containing both soluble salts and exchangeable sodium

9. Soil Properties 1. Saline (non sodic) soils EC > 4 ds/m SAR < 15
pH < 8.5
 "neutral" salts
often calcareous (lime-
containing)
pH =
"white alkali" soils
= white surface crust
2. Saline-Sodic soils
EC > 4 ds/m
ESP (SAR) > 15
pH < 8.5
controlled by salts and lime
pH> 8.5
also called "white alkali“

10. 3. Sodic (non-saline) soils
EC < 4 ds/m
ESP (SAR) > 15
poor physical condition
pH > 8.5
high pH disperses organic matter Þ dark color
= "black alkali"
worst soil of the salt-affected
high dispersion = water-logging
can result from leaching saline-sodic soil
                   

11. Comparisons of Salt-affected Soils

12. Sources contributing salinity
Parent Material
Irrigation water
Ground water
Flood water
Sea water
Salt loving vegetation
Industrial wastage / sewage water
Overuse of chemical Fertilizer

13. Effects on plant growth

14. Sub-soiling Deep ploughing Sanding Horizon mixing Profile inversion
Reclamation of Salt- affected soils
Physical Methods
Sub-soiling
Deep ploughing
Sanding
Horizon mixing
Profile inversion

15. - Flooding - Growing of crops
Biological methods
- Flooding - Growing of crops
- Incorporation of organic matter

16. Chemical Methods
Gypsum (sodic & saline- sodic)
Sulfur
Sulfuric acid
Hydrochloric acid

17. Reclamation of Saline Soils
Reclamation of saline soil is done by applying excess water to the soil surface. The removal of salts may be accomplished either by continuous ponding of water on soil surface or by intermittent leaching.

18. Crop during Reclamation
Some kind of vegetation should be grown during reclamation, as they help reclamation and also provide some income to farmers. As,
Rice
Sesbania
Sorghum
Bermuda Grass
Kallar Grass

19. Salt Tolerance of crops
Tolerant
Moderately Tolerant
Wheat
Sorghum
Soybean
Saf flower
Oats
Sweet Clover
Rhodes Grass
Sudan Grass
Beet
Fig
Jujube
Olive
Papaya
Pine apple
Pomegranate
Barley
Cotton
Sugar beet
Kallar Grass
Wheat Grass (Tall)
Date palm
Asparagus

20. Moderately sensitive Sensitive Bean Sesame Carrot okra Onion Apple
Maize
Millet
Groundnut
Rice
Sugarcane
Sunflower
Barseem
Sesbania
Cabbage
Cauliflower
Corn
Cucumber
Egg plant
Lettuce
Muskmelon
Potato
Pumpkin
Radish
Spinach
Sweet potato
Tomato
Turnip
Water melon
Grape
Bean
Sesame
Carrot
okra
Onion
Apple
Apricot
Grapefruit
Lemon
Lime
Mango
Orange
Peach
Pear
Plum
Strawberry

21. Reclamation of sodic and saline-sodic soil
Reclamation of sodic and saline-sodic soil is more difficult, time consuming and expensive.
It involves not only leaching a soluble salts but also the replacement of exchangeable sodium with calcium and the improvement of physical properties of soil.
The two most difficult aspects of the reclamation process are
- Provision of source for replacement of sodium with calcium
- Water for leaching

22. Management of salt affected soils
Crop selection
Variety selection
Irrigation practices
Ridge sowing
Proper fertilizer and fertilizer use
Green manuring
Organic manures on sodic-soils
Sub-soiling and deep tillage
Mulching