One of the main problems of deforestation in the TRF is that laterization may
occur. Laterization tends to limit the extent of successful soil utilization and retards
forest re-establishment and regeneration.
Processes of Laterization
Laterization is the concentration of iron and aluminium-rich oxides at or near the topsoil. It can also be due to the preferential removal of silica from the soil profile during extensive weathering. Because bases(Ca, Mg, K) are readily available from the abundant vegetation, humid acids are generally absent, therefore the soil is Not very acidic. Due to the absence of humic acids, iron and aluminium oxides are therefore insoluble. These stable oxides therefore accumulate in the soil. These iron and aluminium sesquioxides, if exposed to air, will harden through desiccation to form a rock-like material called laterite.
Human Activities and Laterization
Modern human activities involve extensive removal of surface vegetation, i.e. deforestation. Deforestation leads to changes in the micro-climate and the soil forming processes in the tropical environment.
in the soil forming processes
The soil is exposed to the direct sun/ insolation and atmospheric agents: Evaporation from the soil is increased because of the increased insolation/ baking and wind speed. As a result, desiccation increases and laterization increases. The soil is desiccated and the laterite hardens.
Vegetation removal implies a breakdown in the rapid cycling of bases which would reduce the concentration of sesquioxides in the soil profile. Vegetation cover originally reduces the raindrop impact and runoff. Therefore, due to the lack of protective vegetation cover, soil erosion is increased and hence the soil loss to surface water is increased.
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