Early farmers realized that the different soils and climates they encountered required them to grow certain types of crops in order to survive economically. ‘Major Land Resources Areas of Kerala’ is the brainchild of Sri. Hari Eswaran, Scientist, USDA conceived during the First International Forum on Soil Taxonomy and Sustainable Land Management held in February-March 1993. The basic concept was built up on by the department personnel who identified 27 resource areas in Kerala based on physiography, geology, climate, soils and crops as parameters. A brief description of each Major Land Resource Area is given below.
- Southern coastal plain
They comprise marshes, lagoons, barrier beaches, estuaries and gently sloping plains between beachline & 20 m above MSL. Coconut is raised in garden land; paddy, banana and vegetables are grown in lower plains.
- Southern dissected pedi plain
Undulating plain dissected with broad valleys and isolated low mounds with elevation up to 10 m above MSL. The side slopes are gentle to moderate and cultivated with coconut intercropped with tapioca, banana, arecanut, jack, mango etc. In the valleys, paddy, banana and vegetables are raised.
- Southern lower dissected piedmont plain
These are undulating to rolling lands with elevation 20-60m above MSL interspersed by broad valleys with occasional low laterite mounds. Coconut-predominant mixed cropping with arecanut, tapioca, fruit trees, pepper, yams etc, in garden lands. paddy, banana, sesamum, vegetables, pulses etc., raised in broad valleys.
- Southern upper dissected piedmont plain
Dissected laterite landscape with low laterite mounds & interfluves at 20-100m above MSL. Isolated hills of low altitude. Gently sloping to flat bottom broad valleys. Coconut-predominant mixed cropping system. Rubber as monocrop, tapioca, pepper, cashew banana, fruit trees etc. cultivated. In flood plains, paddy, banana, vegetables and pulses raised.
- Southern lower hill ranges
Elevation 100-300m above MSL. Narrow ridges, residual uplands, residual laterite hills, flood plains, valleys, side slopes, rolling to hilly terrain, elongated alluvial basins and narrow valleys. Moist deciduous & dry deciduous forests occupy major portion. Eucalyptus, teak, bamboo seen on lower reaches. Rubber, tapioca, coconut, cashew, pepper, arecanut etc. grown. In valleys, paddy, banana, vegetables, pulses etc. raised.
- Southern upper hill ranges
Major terrain units are ridges, narrow valleys, denudational slopes, rocky cliff, rocky scarp, dissected scarp etc at elevation 300-600 above MSL. Major portion under moist deciduous forests; wet ever green forests in patches. Plantations of eucalyptus, teak and rubber present.
- Southern steep mountain ranges
Hilly terrain which includes denudational hills, denudational slopes, rocky cliffs, scarp slopes, narrow valleys, terraces etc at 600-1200 above MSL. Wet evergreen forests predominant. Semi-evergreen moist deciduous forest plantations also seen. Tea grown as pure crop.
- Kuttanad coastal basin
Kuttanad is a saucer shaped basin generally 0.5-2m below MSL flanked by sand dunes in the west & low laterite hillsin the east. It is an interface of marine, fluvial & predominantly lacustrine systems modified by human intervention with paddy as the major crop.
- Thrissur kole basin
Thrissur kole basin is a saucer shaped basin with elevation 0.5 to 1m below MSL flanked by sand dunes in the west & low laterite hills in the east; predominantly marine and fluvial. Paddy is the major crop.
- Pokkali area
Low lying marshes, water logged and ill drained areas near rivers and streams subject to tidal waves. Elevation at or below sea level with paddy as the major crop.
- Central coastal plain
Gently sloping coastal belt with sandy plains, low dunes, beach, ridges, backswamps, marshes, lagoons and tidal mudflats at less than 10m elevation from MSL. Coconut is the major crop. In wetland, paddy, banana, sesamum, vegetables, pulses etc. are grown.
- Central lower dissected piedmont plain
Undulating to rolling laterite plains dissected by alluvial broad valleys 20-60m above MSL. Isolated laterite mounds have moderately to steeply sloping side slopes. Coconut is the predominant crop. Other crops include fruit crops, banana, clove and nutmeg. In wet valleys, paddy, banana, vegetables, pulses and tapioca are raised.
- Central upper dissected piedmont plain
Rolling laterite terrain with elevation 20-100m above MSL, highly dissected by alluvial broad valleys. Isolated denudational ridges, laterite plains & terraces. Rubber and coconut dominate. Coconut mixed with cocoa, pepper, tapioca, arecanut & banana. Paddy, banana & vegetables raised in valleys.
- Central lower hill ranges
Rolling hilly terrain with narrow ridges, residual hills, steep side slopes, narrow valleys & flood plains with 100-300m elevation. Rubber, coconut, tapioca, pepper, and arecanut in garden lands, paddy & legumes in wetlands. Forest plantations of Eucalyptus and teak also observed.
- Central upper hill ranges
Hill ranges, denudational hills, scarp slopes, narrow valleys & terraces are the major land forms and found at elevation 300-600m above MSL. Under reserve forests. Forest type semi- evergreen, deciduous and wet evergreen.
- Central steep mountain ranges
Mountainous terrain with denudational slopes, denudational hills, hummocky terrain, isolated hills, rocky cliffs, terraces & narrow valleys at 600-1200m above MSL. Highly eroded rocky summits & steep side slopes of mountains prominent. Major area under reserve forests, wet evergreen, semi evergreen, moist & dry deciduous forest plantations. Tea plantations, cardamom, pepper, garlic, ginger, cool season vegetables, etc. raised.
- Palakkad gap
Undulating to rolling plains, isolated hills, alluvial plains, flood plains, terraces, alluvial basins & reclaimed backswamps at 100-300m above MSL. Coconut, sugarcane, groundnut, cotton, horsegram are raised in garden lands. Paddy & sugarcane in wet valleys.
- Palakkad plain
Undulating to rolling plains, broad isolated low hills, residual hill with rock exposures, flood plains,river cones, terraces & alluvial fans. Elevation 20-100m above MSL. Coconut,banana, vegetables, sesamum etc.,raised in gardenlands.
- Northern coastal plain
Characterized by beach ridges, Paleo sands, sand flats, tidal mud flats, marshes, tidal estuaries, tidal creeks, lakes, coastal alluvial plains & low laterite cliffs. Elevation up to 10m above MSL. Coconut is predominant. Tobacco cultivated in the coast. In wetlands, paddy, banana, vegetables are raised.
- Northern lower dissected piedmont plain
Rolling to undulating plains, laterite mounds, isolated hills, lateritic mesa, flat-bottomed valleys, laterite benches, flood plains, etc are the dominant land forms. Elevation 10-20m above MSL. Coconut arecanut, pepper, cashew, paddy, banana & yams are raised.
- Northern upper dissected piedmont plain
Rolling laterite plains, laterite mesa, laterite mounds, isolated hills, flat bottomed valleys, flat-topped ridges, laterite benches, flood plains, lowland terraces & narrow valleys at an elevation of 20-100m above MSL. Laterite mesa over crystalline rocks is the most prominent feature. Coconut, arecanut, rubber, cashew, vegetables, paddy, banana & pulses are raised. Dry deciduous forest plantations.
- Northern lower hill ranges
Laterite mesa, stepped mesa, residual uplands, undulating terrain, narrow valleys & enclosed alluvial basin at 100-300m elevation. Forest plantations & plantation crops; coconut, tapioca, banana raised in garden lands; paddy, banana in valley fills.
- Northern upper hill ranges
Elevation 300-600m above MSL. Steep ridges, narrow valleys, rocky cliffs, rocky scarp, denudational hills, scarp slopes are the major land forms. Deciduous forest & plantations constitute the major portion. Rubber, pepper, coconut, arecanut, ginger and cashew raised.
- High mountain plateau
More than 1200m above MSL. Rocky cliffs, rocky scarps, denudational slopes, undulating summit tops, rocky & stony phases with little soil cover. Grass & shrub vegetation and shola forests.
- Wayanad plateau
Elevation at 600-1200m above MSL. Denudational plateau slopes, escarpments, rocky hills, gently sloping to rolling lands & plains, dissected plateau, inter mountainous broad valleys and high level flood plains. Crops raised include coffee, tea as plantations, pepper, ginger, turmeric, paddy, banana & vegetables. Moist deciduous and dry deciduous forests cover the east.
- Northern steep mountain range
Mountainous terrain comprising of denudational slopes, denudational hills, hummocky terrain, rocky cliffs, highly undulating terrain, isolated hills, scarp slopes of mountains are prominent. Elevation 600-1200m above MSL. Wet evergreen forests & moist deciduous forest.
- Marayur rainshadow region
Elevation 400-1200m above MSL. Denudational hills, denudational slopes, rocky cliffs, scarp slopes, terraces. Dry deciduous, temperate shola reeds are the major forest types. Potato, millets, cabbage, cauliflower, sugarcane etc. raised.