Volume: X Chapter: 3 Page No:
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Chapter 3: Physical and Biotic factors The total area of the Sn Sub catchment is 36880 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 Sn Sub catchment. 1. Landforms The Landforms of Sn Sub-catchment have been represented in the pie diagram given below. It is evident that Sn sub catchment has two types of landforms viz Steep to very steep high hills of Lesser Himalayas and Fluvial valleys. It is observed that 55% area of the Sn sub catchment is covered by Steep to very steep high hills of Lesser Himalayas while the remaining 45% area is covered with Fluvial valleys. 2. Forest types The forest types of the Sn Sub-catchment have been represented in the pie diagram given below. It is observed that the area under Sn Sub-catchment has 2 types of forests viz
Himalayan moist temperate forest and Sub-tropical pine forest. It is evident that the area occupied by each Forest type is nearly same where Himalayan moist temperate forests cover 49% area while Sub-tropical pine forests cover 51% of the total area of Sn Sub catchment. 3. Rainfall A graphical representation of the various rainfall intensities observed in the Sn Sub catchment: From the pie diagram, it is evident that Sn sub catchment receives rainfall that has 3 ranges viz 1000-1500mm, 1500-2000mm and >2000mm. It is can be noted that maximum i.e. 52% area of
Comprehensive CAT Plan of Satluj River Basin
Volume: X Chapter: 3 Page No:
the Sn sub catchment receives rainfall in the range 15002000mm followed by 42% area receiving 1000-1500mm of rainfall. Rainfall exceeds 2000mm in merely 6% of the total area.
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The Soil type 36 covers the maximum i.e. 49% area of the Sn Sub catchment. This is followed by Soil type 55 and Soil type 64 which cover 19% and 17% area respectively. The Soil type 43 covers 12% area while soil type 60 and soil type 49 cover merely 2% and 1% respectively of the total area.
4. Agro-ecological zones Agro-ecological zone that is present in the Sn Sub catchment is described as Warm, Perhumid, Lesser Himalayas with 270-300 days LGP. It is observed that this Agro-ecological zone is spread uniformly and covers 100% area of the Sm Sub-catchment. 5. Soil types The soil types present in the Sn Subcatchment vary greatly. The Sn sub catchment has heterogeneous type of soil with 6 different soil types. The diagram drawn below shows the distribution of different soil types in the Sn Sub-catchment. Soil type description 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 diagram and also in the further explanation. The description of the soil types is presented in the table given below.
Comprehensive CAT Plan of Satluj River Basin