habitat characteristics

Distribution patterns corresponding to habitat characteristics in tropical forests have not been largely studied. Natural forest structure as well as the anthropogenic alterations to the forests equally affects the distribution patterns of wet zone avifauna. The study reveals the importance of % canopy closure, distance from the forest edge, tree density, diversity, and elevation to the community composition of local forest birds inhabiting Gannoruwa Forest Reserve, Sri Lanka. The most important factors resulting in the study for shaping the avian distribution pattern are distance from the edge,elevation, and the % canopy closure. With the increase of favouring resources to the avian fauna at the edges and the juxtaposition of the edge, many forest loving species were observed to move towards the edge. The pattern is proven advantageous, but harmful in the long run. Thus, it is advisable that the conservation plans should focus on habitat destruction and the anthropogenic disturbance along forest edges.

Apart from the recognition of Thonningia sanguinea as a root parasite of forest trees, information on other aspects such as the nature of its population, habitat preference and distribution range in Nigeria has not been reported. Hence to delineate its presence and current distribution ranges, reconnaissance surveys were carried out across selected forested areas in Southern Nigeria. Records on habitat characteristics comprising host type, elevation, GPS location/orientation, companion plant species, and soil types were collected from sampling sites habouring the plant. This study reports the presence of T. sanguinea in the following locations with an accompanying number of population: Cross River National Park (13), Ehor Nu Wire Forest (3), Okokhuo Forest (3), Okour Forest (2), Iyanomo Forest (2), Okomu National Park (12), Idanre Forest Reserve (2), Ofosu Forest Reserve (3), Oba Hills Forest Reserve (2), IITA Forest Reserve (5), and Omo Forest Reserve (2). Analysis of its habitat features revealed its preference for disturbed habitats, particularly those along forest margins and nature trails, where sunlight reflection reaches the ground. T. sanguinea habitats were characteristically ferrallitic or ferruginous soil. Phytosociological analysis of T. sanguinea habitats showed a regular association with secondary forest indicator species such as Cercestis sp, Harugana madagascariensis, Anchomanes difformis, Musanga cecropioides, Strombosia grandifolia, Icacina trichantia, Myrianthus arboreus. Thus, based on habitat preference, T. sanguinea can best be described as a species that avoid a highly disturbed environment but show a preference for areas with minimal disturbance in a forested environment. Consequently, T. sanguinea could be a potential bio-indicator in predicting environmental degradation in a forested ecosystem.