Effects of Industrial Activities on the Structure and Floristic Pattern of Vegetation within the Calabar Port Authority, South-Southern Nigeria

The paper evaluated the effects of industrial activities on the structure and floristic pattern of woody tree/shrub species in the Calabar Port Authority. Three plots of 0.16 ha were employed to collect vegetation parameters (structure and floristic) from vegetation adjoining highly impacted site (HIS) and of less impacted site (LIS). Shannon-Wiener’s index showed that vegetation in the LIS was more diverse and heterogeneous than vegetation in the HIS with species diversity index of 2.29 and 2.26 respectively; whereas, the index of evenness revealed what tree/shrub species encountered at the HIS (0.53) were fairly equally abundant compared to tree/shrub species in the LIS (0.44). Vegetation in the LIS was richer at both spatial scale and taxonomic level than vegetation in the HIS, as a result of the favourable edaphic conditions and absence of toxic substances that facilitated vegetation growth. Therefore, to preserve the threatened diversity of available tree/shrub species in the area, government was encouraged to enact laws to stop the destruction and transformation of remaining hectare of vegetation into industrial and residential estates.