Topography & Geography

Sahyadri Tiger Reserve, situated along the crest of the northern Western Ghats, is characterized by a rugged mountainous landscape, high rainfall, and an intricate network of rivers and reservoirs. Its varied topography, unique geology, and favourable climate support a wide range of forest types and habitats, making the reserve one of the most ecologically significant protected areas in the northern Western Ghats. These physical features play a crucial role in sustaining the reserve’s exceptional biodiversity and ecological processes.

  1. Physiography and Terrain
    • Sahyadri Tiger Reserve is situated along the crest of the northern Western Ghats, one of the world’s eight “hottest” biodiversity hotspots.
    • The reserve is characterized by a rugged and mountainous landscape comprising steep escarpments, deep valleys, narrow ridges, rolling hills, dense forests, and extensive lateritic plateaus (locally known as Sadas).
    • Elevation ranges from 343 m to 1,236 m above mean sea level, creating a wide variety of microhabitats and climatic conditions.
    • The highly dissected terrain supports diverse vegetation types, influences wildlife distribution, and forms an intricate network of perennial streams and seasonal drainages.

  2. Geology
    • The reserve forms part of the Deccan Trap volcanic province, which originated from extensive basaltic lava flows during the Late Cretaceous period.
    • Geological studies indicate the presence of multiple basaltic lava flows (Wai Sub-group) consisting of compact, vesicular, and amygdaloidal basalt formations.
    • Lateritic caps occur above approximately 900 m elevation, particularly across the western hilltops and plateaus.
    • Alluvial deposits occur along the banks of major rivers such as the Koyna, Warna, Venna, and Kandati, consisting of sand, pebbles, and boulders.
    • The reserve’s geology has been shaped over millions of years by volcanic activity, tectonic movements, and erosion, resulting in its present-day rugged landscape.

  3. Rocks and Landforms
    • Basalt is the dominant rock type throughout the reserve and forms the characteristic plateaus, cliffs, and escarpments.
    • Extensive lateritic rocks cap the higher hilltops, creating the unique rocky plateaus (Sadas) that support specialized endemic flora and fauna.
    • Localized deposits of alluvium occur along river valleys and floodplains.
    • The reserve exhibits diverse geomorphological features including, Deep valleys, Narrow ridges, Rocky escarpments, Lateritic plateaus, Seasonal waterfalls, Perennial streams.
    • These landforms create a highly heterogeneous landscape supporting exceptional biodiversity.

  4. Soil
    • The soils are primarily derived from the weathering of Deccan Trap basalt.
    • Major soil types include:
    o Lateritic soils on higher plateaus and western hilltops.
    o Red and yellow soils on weathered slopes.
    o Alluvial soils along river valleys and floodplains.
    o Mountain Soil
    o Clayey and loamy soils in gentle valleys and lower slopes.
    o Lateritic Plateau soil
    • Lateritic soils are generally shallow, porous, acidic, and well-drained, while valley soils are deeper and comparatively fertile.
    • The region contains economically important mineral deposits such as bauxite, associated with lateritic cappings

  5. Hydrology and Water Resources
    • Sahyadri Tiger Reserve forms an important watershed in the northern Western Ghats.
    • Numerous perennial streams originate from the high hills and feed the:
    o Koyna River
    o Warna River
    o Kandati River
    o Kadavi River
    o Venna River
    • The reserve contains an extensive network of rivers, streams, nalas, waterfalls, and wetlands that provide year-round water for wildlife.
    • Two major reservoirs occur within the reserve:
    o Koyna (Shivsagar) Reservoir
    o Chandoli (Vasant Sagar) Reservoir
    • These freshwater ecosystems support rich aquatic biodiversity and regulate regional hydrology.

  6. Climate
    • Sahyadri Tiger Reserve experiences a humid tropical monsoon climate with three distinct seasons:
    o Monsoon (June–September)
    o Post-monsoon/Winter (October–February)
    o Summer (March–May)
    • The climate remains generally moderate throughout the year because of dense forests and high elevation.

  7. Temperature
    • Temperature varies with elevation across the reserve.
    • Average summer temperatures (April–May) range between 20°C and 24°C.
    • Winter temperatures (December–February) generally range between 18°C and 24°C.
    • Higher elevations remain cooler, while valleys experience comparatively warmer conditions

  8. Rainfall
    • The reserve receives abundant rainfall from the Southwest Monsoon.
    • Approximately 85% of the annual rainfall occurs between June and September.
    • Average annual rainfall ranges from 3,000 to 5,000 mm, with the western windward slopes often receiving more than 6,000 mm.
    • In 2019, Patharpunj village within the reserve recorded 7,359 mm of rainfall (June–September), the highest rainfall recorded in India during that period.

  9. Humidity and Wind
    • Relative humidity remains high throughout the year and generally exceeds 80% during the monsoon season.
    • The reserve is strongly influenced by southwest monsoon winds, which bring heavy rainfall to the western slopes.
    • Dense forests, valleys, and steep escarpments create localized microclimates with persistent mist, cloud cover, and occasional fog during winter.
 
Scroll to Top