Effect of secondary succession on the changes in soil physicochemical properties in the Cross River Rainforest, Nigeria

This study anchored on how secondary succession has affected the soil physico-chemical properties in the Cross River rainforest. The objective of the paper was to examine changes in surface and subsurface soil as influenced by secondary succession and the contributions made by the changes in relation to nutrients upgrade. The study area was the Oban group forest within the Southern part of Cross River State. Five succession phases were identified as follows forbs area (2-years old), young fallow (3-7 years) mature fallow (8-15 years) secondary climax (16-25 years) and primary climax (25 years and above). The soil samples were collected at the surface (0-15cm) and subsurface (15-30cm) levels. From the study findings, it was discovered that sand constituted more than 65% of the inorganic mineral fragment. Furthermore, the soils were classified as loamy-sand. However, there was a substantial increase in the levels of organic carbon and total nitrogen in the top soil across the various succession phases mostly in the mature fallow and primary climax. Hence, this increase in organic carbon and total nitrogen is attributed to the increase in the density of tree/shrubs, dense crown cover and the high amount of litter production through decomposition, thus, adding nutrient to the soil. Therefore, with a viable and functional luxuriant Cross River Rain-forest, the livelihood sustainability of the forest community dwellers/inhabitants could be guaranteed upon the continuous availability of forest resources and services, vis-a-vis poverty alleviation.