Volume: XII Chapter: 3 Page No:
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Chapter 3: Physical and Biotic factors The total area of the Sq Sub catchment is 62581 Ha. This Sub catchment has varied landforms, Forest types, Rainfall patterns, Agro-ecological zones and Soil types. This chapter gives a brief account of the Sq Sub catchment. 1. Landforms The pie diagram drawn below represents the types of landforms present in the Sq sub catchment. It is observed that 2 types of landforms are present in the Sq Sub catchment; they are steep to very steep high hills of Lesser Himalayas and Fluvial valleys. Steep to very steep high hills of Lesser Himalayas cover 74% of the total Sub catchment area while Fluvial valleys are spread over 26% of the total Sub catchment area. 2. Forest types It is observed that the entire area of Sq Sub-catchment has homogeneous type of forests. Himalayan moist temperate forest is the only forest type present in this Sub catchment.
3. Rainfall A graphical representation of the various rainfall intensities shows that the total area of Sq Sub catchment is 62581Ha of which 69% area receives moderate rainfall in the range of 750-1000mm while 10001500 mm of rainfall is observed in 27% of the total area. It is seen that merely 4% area receives low rainfall which is less than 700mm. 4. Agro-ecological zones The graph shows the distribution of Agro-ecological zones in the Sq Sub catchment, where there are two types of Agroecological zones present in the Sq Sub catchment, they are described as Warm, Perhumid, Lesser Himalayas with 270-300 days LGP and Warm, Sub-humid, Moist, Lesser Himalayas with 180-270 days LGP. It is seen that the Agro-ecological zone described as Warm, Perhumid, Lesser Himalayas with 270-300 days LGP covers maximum i.e. 95% area of Sq Sub catchment while only 5% area is covered by the Agro-ecological zone described as Warm, Sub-humid, Moist, Lesser Himalayas with 180-270 days LGP.
Comprehensive CAT Plan of Satluj River Basin
Volume: XII Chapter: 3 Page No:
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5. Soil types The soil types present in the Sq Sub-catchment are quite varied. It is observed that the entire Sub-catchment has 8 different types of soils. The pie diagram drawn below shows the distribution of soil types in the Sq Subcatchment.
Note: The name of each soil types being very descriptive, we have denoted them as Soil types units. This nomenclature is used in the above graph and also in the further explanation. The description of the soil types is presented in the table 1. The pie diagram represents that the Soil type 48 covers 38% area while Soil type 29 constitutes to 20% area of the Sq Sub catchment. Soil type 36 covers 15% area of the region. While Soil types 54 and Soil type 43 each covers 10% area of the Sub catchment. The Soil type 32, Soil type 16 and Soil type 27 are also present in some areas of the region.
Table 1: Soil type description Soil Description Rock outcrops associated with deep, excessively drained, sandy-skeletal soils with loamy surface, very severe erosion and moderate stoniness. Shallow, somewhat excessively drained, mesic, coarse-loamy soils on moderate slopes with loamy surface and severe drained, fine-loamy soils with loamy surface and severe erosion. Rock outcrops associated with, Medium deep, excessively drained, mesic loamy-skeletal soils on very steep slopes with loamy surface, severe erosion and moderate stoniness. Rock outcrops, associated with Medium deep, somewhat excessively drained, mesic, sandy soils on steep slopes with sandy surface and severe erosion. Shallow, excessively drained. Thermic, sandy-skeletal soils on steep slopes with loamy surface, very severe erosion and strong stoniness, associated with, Rock outcrops. Shallow, well drained, thermic. loamy, skeletal soils on moderate slopes with loamy surface, moderate erosion and moderate stoniness, associated with Shallow, somewhat excessively drained, coarse-loamy soils with loamy surface, severe erosion and severe erosion and slight stoniness. Medium deep, well drained, thermic, fine loamy calcareous soils on moderately steep slopes with loamy surface and severe erosion, associated with, Medium deep, well drained, fine-loamy soils with loamy surface and moderate erosion. Medium deep to deep, well drained, thermic. Fine-loamy soils on steep slopes with loamy surface and moderate erosion, associated with medium deep, well drained, coarse-loamy soils with loamy surface and severe erosion.
Comprehensive CAT Plan of Satluj River Basin
Soil type unit 16 27 29 32 36
43 48 54