Multivariative Analysis of Environmental Factors Affecting Nematode Distribution Along The Continental Slope Off The Kenyan Coast

Abstract

Nematodes are very useful organisms in marine ecosystem. They facilitate re mineralization and uptake of detritus by other organisms thereby making complete the food chain of the marine ecosystem. A study on the environmental variables that affect presence - absence of the organisms is essential in ensuring secure habitats are provided for the nematodes. In this study, multivariate methods are used to test for significant differences in nematode abundances between different transects and water depths in the Northeast and Southeast monsoon seasons. A comparison of the two seasons indicates no significant differences in Nematode densities between the seasons implying that either season can be used independently to test for environmental variables that relate to the genus composition of the nematodes. Canonical correspondence analysis is then used on the Northeast monsoon data to detect genus-environment relations and test for the environmental variables that significantly explain the variation in genus data. The results of this study indicate that a high percentage of variation in nematode composition can be explained by the environmental variables. The study would not be complete without an investigation of the diversity of the nematodes at genus level along the different transects of the Northeast monsoon data. Simpson's diversity index is used as a measure of diversity and further studies that explain the causes of the varying diversities along the four transects recommended.