Geospatial Trend of Phytodistribution Pattern of Cryptogamic Ferns in a Rainforest Vegetation

Abstract

Background and Objective:The majority of ferns inhabit a wide range of habitats (from terrestrial, arboreal to aquatic) with either species being obligatory or facultative in their preference for ecological niche adaptation and tolerance to varying landscape physiognomy. This work was carried out at the three sub-ecological stations of International Institute of Tropical Agriculture, Onne, Rivers state, Nigeria and the objective is to assess the distribution and arrangement of fern in space using geospatial techniques in rainforest vegetation. Materials and Methods: Ground trothing ecological sampling methods, GPS for species georeferencing and ArcGIS software, (version 10.8 2021) for Nearest Neighbourhood Ratio and Autocorrelation analyses within sampling plots and among species across sampling plots of stations. Results: Nine species (Nephrolepis biserrata, Marattia fraxinea, Selaginella myosurus, Bubophyllum barbigerum, Pteris captoptera, Pteris pacifica, Nephrolepis pumicicola, Pteris burtonii and Diplazium sommatii) under six families existed in diverse niche habitation (one obligatory arboreal, six obligatory terrestrial forest floor and two facultative terrestrial/arboreal habitat). Phytospatial distribution in station I had Nephrolepis biserrata (random); Marattia fraxinea, Seleginella myosurus, Pteris pacifica and Pteris burtonii (clustered); in station II Pteris pacifica, (dispersed) and Pteris burtonii and Seleginella myosurus (clustered) and Seleginella myosurus (dispersed). Conclusion: This study has identified fern species across the various modes of habitation besides the variation while in their spatial distribution pattern. However, a clustered distribution pattern for all ferns was recorded with the spatial autocorrelation analysis.