Volume: I: Part I: Section: 3 Chapter: 3
3.3.1
Section 3: Chapter 3: Physical Factors (Agro-Ecological zones) India is gifted with heterogeneous landforms. It has a variety of climatic conditions like the lofty mountains, raverine deltas, high altitude forests and peninsular plateaus. Besides it is also endowed with temperatures varying from arctic cold to equatorial hot, and rainfall from extreme aridity with only a few cms (<10 cm) to perhumid with worldâ&#x20AC;&#x2122;s maximum rainfall (1120 cm) of several hundred cms. These factors have led to formation of varied landforms like high plateau, open valleys, rolling upland, plains, swampy low lands and barren deserts. Such varying environmental situations in the country have resulted in a greater variety of soils. Therefore, the systematic appraisal of agroecological regions has tremendous scope in grouping relatively homogenous regions in terms of soil, climate and physiography and conducive moisture availability periods (length of growing season).1
Climate of the study region is cold or warm. The climate is dependent on the elevation of the region. Our project area has a variety of bioclimatic conditions that range from Arid, Semi-arid, Semi-dry, Dry, Sub-Humid, Per humid to Moist. The physiography or location of our project is the Lesser or Greater Himalayas. The length of growing period refers to the time taken in days by the crops grown in the particular region. Here the LGP ranges from less than 60 days to 330 days. It can be observed here that time required for the growth of crops increases as we go from higher elevation to lower elevation.
The nomenclature used in describing AEZ may be denoted as CBcPL Where: C= Climate Bc = Bioclimate P= Physiography LGP= Length (days)
of
growing
period
1 K.S Gajbhiye and C.Mandal, Agro-Ecological Zones, their Soil Resource and Cropping Systems ,National Bureau of Soil Survey and Land Use Planning, Nagpur
Comprehensive CAT Plan of Satluj River Basin
Volume: I: Part I: Section: 3 Chapter: 3
3.3.2
The agro-ecological zones (AEZ) which are present in our project area are: Sr No
Agro-ecological zone
Unit
1
Cold, Arid, Greater Himalayas with <60 days LGP
1
2
Cold to Warm Semi-arid, Semi-dry, Greater Himalayas with 60-120 days LGP
2
3
Warm, Dry, Sub-Humid, Greater Himalayas with 120-180 days LGP
3
4
Warm, Sub-humid, Moist, Lesser Himalayas with 180-270 days LGP
5
5
Warm, Per humid, Lesser Himalayas with 270-300 days LGP
6
6
Humid/Per humid, Lesser Himalayas with 300-330 days LGP
7
Note: Units are assigned to the agro-ecological zones so as to facilitate short and simple representation of the agro-ecological zones which are descriptive in nature. Henceforth these units will be used as names of the agro-ecological zones.
Farms on the banks of Spiti â&#x20AC;&#x201C; A view from the Key Monastery
Comprehensive CAT Plan of Satluj River Basin
Volume: I: Part I: Section: 3 Chapter: 3
3.3.3
The LGP refers to Length of growing period in days for a certain crop. The distribution of the agro-ecological zones in our project area can be seen in the map given below:
Legend: Cold, Arid, Greater Himalayas with <60 days LGP Cold to Warm Semi-arid, Semi-dry, Greater Himalayas with 60120 days LGP Warm, Dry, Sub-Humid, Greater Himalayas with 120-180 days LGP Warm, Sub-humid, Moist, Lesser Himalayas with 180-270 days LGP Warm, Per humid, Lesser Himalayas with 270-300 days LGP Humid/Per humid, Lesser Himalayas with 300-330 days LGP Satluj river Sub catchment boundary
Map showing the distribution of various agro-ecological zones in the Satluj catchment
Comprehensive CAT Plan of Satluj River Basin