SPECIES RICHNESS, DIVERSITY AND DISTRIBUTION OF AMPHIBIANS ALONG ELEVATIONAL GRADIENT ON MOUNTAIN AFADJATO, GHANA

Year 2013, Volume: 1 Issue: 2, 68 - 76, 16.06.2013

Daniel Agyei Edward Wiafe

Abstract

 Numerous studies have confirmed Altitudinal gradients and physical environment as the major factors that affect species richness and distribution. The world's biodiversity are not evenly distributed due to the variations in biogeographically conditions. The West African tropical rain forest ecosystem host about two- thirds of the earth's biodiversity however, little information is known about this rich biodiversity especially the factors that link species  richness and distribution. In this study, the richness and distribution of amphibians were investigated. In this regard, systematic sampling was used as a method to determine amphibian species richness and distribution along the three levels of elevation. Litter levels were also recorded to determine the effect of litter levels as ecological variable on amphibian's richness and distribution. The instruments used include GPS, ruler, a hundred meter line tape and compass. The result reveals a significant variation of amphibian's richness and diversity along elevational gradient. However there was a negative relationship between amphibian species and litter levels along the lower, middle and upper elevational levels.

Keywords

Amphibian, Elevation, Leaf litter, Afadjato, Ghana

SPECIES RICHNESS, DIVERSITY AND DISTRIBUTION OF AMPHIBIANS ALONG ELEVATIONAL GRADIENT ON MOUNTAIN AFADJATO, GHANA

Abstract

Bu çalışmada amfibi tür çeşitliliği ve dağılımını incelemek üzere sistematik örnekleme yapılarak, amfibi türlerinin üç yükseltideki dağılımı incelenmiştir. Elde edilen bulgulara göre; tür zenginliği ve dağılımı yükselti boyunca anlamlı bir şekilde değişirken, tür çeşitliliğinin yükseltiye göre değişmediği tespit edilmiştir. Ayrıca Arthroleptis spp. ve Phrynobatracus calcaratus türlerinin Afadjato dağında en fazla yaygınlık gösteren ve yaşam rekabetinde üstünlük gösteren türler olduğu sonucuna varılmıştır. Yükselti boyunca ölü örtü seviyesi ile amfibi türlerinin yaygınlığı arasında negatif bir ilişki olduğu görülmüştür. Yükselti boyunca artış gösteren ölü örtü miktarına karşın amfibi tür sayısının azalması ile Afadjato dağında amfibilerin ölü örtünün fazla olduğu yerleri tercih etmediği sonucuna varılmıştır.

Keywords

Amfibi, Yükselti, Ölü örtü, Afadjato, Gana

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