Before going to learn about types of soils in Pakistan ,we need to go through five main types of soils .
There are roughly four different types of soil, based on differences in structure and texture: clay, sand and gravel, silt, and loam. A fifth type, organic soil, is less common. The descriptions that follow will help you identify your soil type.
1.Clay soils
Clay soil, composed of many small, flat particles, feels sticky or plastic in your hands. Clay comes in many colors: red, yellow, bluish gray, or almost black. Clay soils warm up and dry out slowly, take in water slowly, and can store reserves of nutrients better than most other soils.
Clay can become as hard as a rock duting dry, warm weather if not watered regularly. Once dried out, it is almost impossible to water clay soil adequately with sprinklers. The surface seals over and stops water from penetrating easily. If this happens, you should make irrigation furrows to hold the water until it can soak in. Improve clay soils by digging in generous amounts of organic matter, such as peat moss, compost, or well- rotted manure, to improve drainage and aeration. Gypsum also helps improve the texture of clay, but does not add nutrients to the soil. Adding only sand to clay will not improve it; the soil will continue to form crusts
Clay soil, composed of many small, flat particles, feels sticky or plastic in your hands. Clay comes in many colors: red, yellow, bluish gray, or almost black. Clay soils warm up and dry out slowly, take in water slowly, and can store reserves of nutrients better than most other soils.
Clay can become as hard as a rock duting dry, warm weather if not watered regularly. Once dried out, it is almost impossible to water clay soil adequately with sprinklers. The surface seals over and stops water from penetrating easily. If this happens, you should make irrigation furrows to hold the water until it can soak in. Improve clay soils by digging in generous amounts of organic matter, such as peat moss, compost, or well- rotted manure, to improve drainage and aeration. Gypsum also helps improve the texture of clay, but does not add nutrients to the soil. Adding only sand to clay will not improve it; the soil will continue to form crusts
2.Sand and gravel soils
If your soil looks and feels like a sandbox or gravel pit, you have sandy or gravelly soil. Sandy soil is easy to work and warms up rapidly. However, it dries out quickly and then may blow around. In direct sun it can reflect enough heat to damage a vegetable crop. Fortunately, most sandy soils contain enough clay particles to make them reasonably responsive to fertilizers. Pure sand contains almost no nutrients and has little capacity to store moisture. However, most sandy soils have enough clay particles to hold some nutrients.
Gravelly soils are usually a mixture of gravel and sand, silt, or clay. Generally low in organic matter, they are also low in natural fertility. The best way to improve sandy or gravelly soil is to remove the larger pebbles and stones; then add coarse organic matter, such as peat moss, compost, or well-rotted manure. Clay added to sandy or gravelly soils will tend to collect in impervious layers instead of improving the soil.
Gravelly soils are usually a mixture of gravel and sand, silt, or clay. Generally low in organic matter, they are also low in natural fertility. The best way to improve sandy or gravelly soil is to remove the larger pebbles and stones; then add coarse organic matter, such as peat moss, compost, or well-rotted manure. Clay added to sandy or gravelly soils will tend to collect in impervious layers instead of improving the soil.
3.Silt soils Silt has an intermediate size between clay and sand. It consists of small, gritty particles that can pack down very hard. Silt ranges in color from gray to tan, yellow, and red. It�s usually not very fertile. Silt topsoils are often found over dense layers of clay that slow or stop drainage.
Both the topsoil and these lower layers should be broken up and kept loose by adding copious amounts of peat moss, compost, well-rotted sawdust, or wood shavings. Adding organic matter will improve the structure and fertility of silt soils. Adding clay or sand will not improve silt.
4.Loam Soils
Both the topsoil and these lower layers should be broken up and kept loose by adding copious amounts of peat moss, compost, well-rotted sawdust, or wood shavings. Adding organic matter will improve the structure and fertility of silt soils. Adding clay or sand will not improve silt.
4.Loam Soils
Loam contains various proportions of clay, silt, sand, and organic matter. The proportions of each determine how easy the soil is to cultivate and how productive it is. Sandy loam with a fairly high content of organic matter is the easiest to cultivate, water, and weed. A loam that contains more than one-third clay acts almost like solid clay and needs lots of added organic matter to make it easy to manage.
5.Organic soils
Dark in color, organic soils are composed largely of peat moss or leaf mold. Your soil is not likely to be organic unless your house is built on an old lakebed, bog, or forest site. Organic soils are easy to work, weed, and water, but may warm up slowly because they retain moisture.
Since organic soils are usually high in nitrogen, they can benefit from fertilizers high in phosphate and potassium. Micronutrient deficiencies (of iron, copper, cobalt, zinc, and manganese) are common in this kind of soil, but can be remedied by using special fertilizers containing the missing nutrients.
Dark in color, organic soils are composed largely of peat moss or leaf mold. Your soil is not likely to be organic unless your house is built on an old lakebed, bog, or forest site. Organic soils are easy to work, weed, and water, but may warm up slowly because they retain moisture.
Since organic soils are usually high in nitrogen, they can benefit from fertilizers high in phosphate and potassium. Micronutrient deficiencies (of iron, copper, cobalt, zinc, and manganese) are common in this kind of soil, but can be remedied by using special fertilizers containing the missing nutrients.
Types of Pakistan's soil
Aridity prevailing over major part of Pakistan is the main climatic characteristic that affects its soils. This has resulted in limiting the soil moisture and scantiness of vegetative cover. Soils in Pakistan are rich inBasic but poor in Nitrogenous matter.
1-Parent Material
The soils of Pakistan are derived from two types of parent materials:
1. Alluvium, Loess and wind reworked sands. They are of mixed mineralogy.
2. Residual material obtained from weathering of underlying rocks. Most of the rocks are Calcareous . In some areas, Granites have produced non-calcareous soil material. Very small quantities of salts are released from most of the rocks. The soils are therefore, essentially non-saline.
2. Soil Classification
The soils of Pakistan have acquired distinct characteristics from the parent material and by their mode of formation. The river-laid sediments have developed into Alluvial Soils. The desert sands have turned into distinct soils. The hills, mountains and the plateaus have produced Residual Soils with patches of Alluvial, Loess and other soils. Accordingly, the soils of Pakistan can be classified into the following six types:
Alluvial Soils of the Flood Plains
Alluvial Soils of the Bar Uplands
Soils of the Piedmont Plains
Desert Soils
Soils of Potwar Plateau
Soils of Western Hills
Alluvial Soils of the Bar Uplands
Soils of the Piedmont Plains
Desert Soils
Soils of Potwar Plateau
Soils of Western Hills
Based on these broad classes, Table 4 presents areas under different soil types in Pakistan. Map 13 presents the 26 broad Soil Types of Pakistan.
Soil Type
Area
(000� ha)
Percentage %
1. Loamy and sandy stratified soils
1.0
0.1
2. Loamy and clayey non-calcareous soils
4.6
0.6
3. MOUNTAINS: Loamy shallow soils
VALLEYS : Loamy non-calcareous soils
18.6
2.3
4. Loamy sandy stratified soils
1.5
0.2
5. Loamy clayey non-calcareous soils
7.7
1.0
6. Loamy non-calcareous soils of alluvial/loess plains
18.2
2.3
7. MOUNTAINS: Loamy and shallow soils
VALLEYS : Laomy soils
10.2
1.3
8. MOUNTAINS: Rock out-crops loamy and shallow soils
VALLEYS : Loamy soils
17.0
2.1
9. Loamy partly gravelly soils
0.7
0.1
10. MOUNTAINS: Loamy shallow soils and rock out-crop
VALLEYS : Loamy soils
2.7
0.3
11. MOUNTAINS: Rock out-crop and loamy very shallow soils
VALLEYS : Loamy soils
41.7
5.2
12. MOUNTAINS:Rock outcrop, some loamy very shallow
soilsVALLEYS : Mainly loamy soils
22.7
2.9
13. Laomy sandy stratified soils
18.8
2.4
14. Loamy clayey soils
90.4
11.4
15. Loamy soils of old river terraces
21.9
2.8
16. Laomy clayey mainly dense saline sodic soils
2.0
0.3
17. Loamy and clayey partly slaine sodic soils
52.7
6.6
18. Mainly loamy saline soils
15.3
1.9
19. Silty and calyey saline soils
5.6
0.7
20. Rolling to hilly sandy soils
116.9
14.7
21. Mainly loamy partly gravelly soils
46.6
5.8
22. Mainly loamy partly gravelly soils
16.7
2.1
23. MOUNTAIND: Rocky out-crop with patchy soils
VALLEYS : Mainly loamy partly gravelly soils
244.5
30.6
24. Clayey and loamy severly slaine sodic soils
2.7
0.3
25. Glaciers and snow caps
3.4
0.4
26. Rivers
13.0
1.6
TOTAL:
796.1
100.0
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