Soils of Nagaland for Nagaland PSC

Soils of Nagaland

  • Nagaland consists of a narrow strip of hilly country running North-east to South-west and facing the Assam plains to its North and North-west.
  • The Barail range enters the state at the South- west corner and runs in a North-easterly direction almost up to Kohima.
  • Near Kohima the Barail range merges with the mountain ranges which have extended to Manipur and the main range assumes a much more northerly trend.
  • This range is considerably higher than the Barail, with peaks like Saramati (3826.15 m) and Mataung Kien (3420 m) at its extreme east.Soils of Nagaland
  • Between Mao and Kohima, there are several very high peaks including Japvo.
  • North of Kohima the main range declines in height, and as far north as Mokokchung district, the Japukong range attains an average elevation of 750m.
  • In general, 94% area falls under hilly and rugged terrain and only 6% land is plain, especially those bordering Assam plains along western boundary of the state.
  • The State has a rolling landscape with low hills covered with very dense vegetation
  • The Soils of Nagaland belong to 4 orders, 7 sub-orders, 10 great groups, 14 sub groups and 72 soil families.
  • The 4 orders found in Soils of Nagaland are
  1. Alfisols
  2. Entisols
  3. Inceptisols
  4. Ultisols
  • Inceptisols dominate the soils of the State with 66% followed by Ultisols 23.8%, Entisols 7.3% and Alfisols 2.9% of the total 16.6 million Hectares of the State Geographical area.

ALFISOLS of Soils of Nagaland

  • Alfisols are base-rich mineral soils of sub-humid and humid region.
  • They have light coloured surface horizon over a clay enriched sub –surface horizon that is rich in exchangeable cations with base saturation of more than 35%.
  • This type of soil order is found on the western flank of the State bordering Assam.
  • They are deep and well drained of fine to fine loamy texture.
  • They have a clay-enriched subsoil and relatively high native fertility.
  • “Alf” refers to aluminium (Al) and iron (Fe).
  • Because of their productivity and abundance, the Alfisols represent one of the more important soil orders for food and fiber productio
  • Common families of Alfisols which have been identified in Nagaland are :
  1. Fine Typic Kanhapludalfs
  2. Fine Loamy Typic Paleudalfs

ENTISOLS of Soils of Nagaland

  • They are recently developed, mineral soils with no diagnostic horizon.
  • This is because either of limiting time available for development or because of exceedingly unfavourable conditions.
  • In USDA soil taxonomy, entisols are defined as soils that do not show any profile development other than an A horizon.
  • An entisol has no diagnostic horizons, and most are basically unaltered from their parent material, which can be unconsolidated sediment or rock.
  • This soil order is found in the Western and North Western part of the State on the low hill slope and narrow river valleys.
  • They are moderately to deep, well drained, fine to fine loamy textured soils.
  • Families which have been identified under this orders are :-
  1. Fine-loamy typic Udifluvents
  2. Fine-loamy typic Udorthents
  3. Coarse-loamy typic Udorthents
  4. Fine-loamy Lithic Udorthents
  5. Coarse loamy Lithic Udorthents

INCEPTISOLS of Soils of Nagaland

  • This soil order represents beginning stage of soil formation which belong to that of Entisols but still short of the degree of development found in Alfisols.
  • They may have some accumulation of clay in the sub-surface horizon, limiting in depth, organic matter content, and base saturation.
  • Although not found under aridic climate regimes, Inceptisols nevertheless are widely distributed and occur across a wide range of ecological settings
  • This soil dominates the entire State having fine loamy, fine clay, clay loam etc.
  • The identified families under this order are:
  1. Fine- loamy Umbric Dystrochrepts
  2. Fine loamy typic Dystrochrepts
  3. Fine Umbric Dystrochrepts
  4. Loamy , skeletal Umbric Dystrochrepts
  5. Fine typic Dystrochrepts
  6. Loamy-skeletal typic Dystrochrepts
  7. Clayey-skeletal Umbric Dystrochrepts
  8. Loamy-skeletal Pachic Haplumbrepts
  9. Fine Pachic Haplumbrepts
  10. Fine-loamy typic Haplumbrepts
  11. Clayey-skeletal Pachic Haplumbrepts
  12. Fine loamy Pachic Haplumbrepts
  13. Fine-loamy Dystric Eutrochrepts
  14. Coarse loamy typic Dystrocrepts
  15. Loamy skeletal typic Dystrocrepts
  16. Loamy skeletal Dystric Eutrocrepts

 

 

ULTISOLS of Soils of Nagaland

  • The Ultisols are similar with Alfisols, except for having low base saturation on the exchange complex due to advance stage at weathering.
  • These are base-poor mineral soils of humid region developed under high rainfall and forest vegetation.
  • The high acidity and relatively low quantities of plant-available Ca, Mg, and K associated with most Ultisols make them poorly suited for continuous agriculture without the use of fertilizer and lime
  • They are characterized by low, less than 35% base saturation and clay enriched sub-surface horizon.
  • This soil is sparely scattered in all parts of the State having fine loam, clay loam and clayey texture.
  • Well to excessively drained with moderate to deep soils. The families under this order which have been identified so far are :
    1. Fine Humic Hapludults
    2. Fine Typic Paleudults
    3. Fine Typic Haplohumults
    4. Fine Loamy Typic Hapludults