Soil
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The general and average soil character of cultivable land in these districts is mainly alluvial and composed of mixture of sand (coarse to fine) and clay in varying proportions. The general geochemical characteristics of the soil is highly acidic. However, new alluvial soils formed due to inundation of land by river at intervals contain more percentages of fine sand fine silt and are less acidic. Such soils are often neutral and even alkaline. Large expanse of low-lying land characterized by heavy clayish soil with a high percentage of nitrogen is good for rice cultivation. Abundant rainfall and excessive humidity through out the year also greatly favor cultivation of rice in the district .The soil around the Subansiri and Ranganadi rivers are sandy coated with silt which is good for cultivation of winter crops, such as raga, and mustard, potato etc.
The soils of this district can be broadly classified into three different zones viz. The foothill soils, active flood plain soils near the river Bramhaputra and the low-lying marshy lands. A more detailed description is given below:
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ZONES |
DESCRIPTION |
Taxonomic Name |
|
Piedmont |
Deep, well drained, loamy sand/sandy loam soils occurring on very gently sloping piedmont plain having loamy surface with moderate erosion and slight flood hazard
Associated with deep, well drained, coarse silty soils occurring on very gently sloping concave plains having loamy surface with slight erosion and moderate flood hazard. |
Coarse loamy, typic fluvaquents,
Coarse silty, Typic Haplaquents |
|
Flood plain |
Deep, well drained, loamy sand/sandy loam soils occurring on very gently sloping flood plain, having loamy surface with moderate erosion and moderate flood hazard,
Associated with very deep, moderately well drained, clay loam or sandy clay loam soils occurring on level to nearly level flood plains with slight erosion and moderate flood hazard. |
Coarse loamy, Aeric fluvaquents,
Fine loamy, Typic Haplaquepts |
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Marshy lands |
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