Patterns of Tropical Tree Species Richness along Elevational Gradients of Mountain Afadjato, Ghana

Year 2014, Volume: 2 Issue: 2, 18 - 23, 25.01.2015

Edward Wiafe

Abstract

This paper evaluates the effect of altitude on tree species richness, diversity, growth pattern and tree abundance to assess the responses of tree species to environmental changes. The highest mountain in Ghana, Afadjato, was categorized into three namely, lower elevation (200m -400m ASL), middle elevation (400m-600m ASL) and from 600m ASL and above the mountain as upper elevation. On five transects running from the bottom to the top of the mountain, two 20m by 20m squared plots were laid in each category on any 20m rise in altitude along the gradient of the mountain. All trees greater than 5cm in diameter at 1.3m above ground were identified and measured. The species richness, basal areas of trees and diversity differed in all the three levels of elevation. Tree abundance was found to decrease with increasing altitude. It was thought that these variations could be attributed to the various micro-environmental differences that might have occurred as a result of edaphic and climatic factors. Recommendations have been made for future studies.

Keywords

Elevation, Ghana, Mountain, Species richness, Tropical trees

PATTERNS OF TROPICAL TREE SPECIES RICHNESS ALONG ELEVATIONAL GRADIENTS OF MOUNTAIN AFADJATO, GHANA

Abstract

Bu çalışma ile ağaç türlerinin çevresel değişimlere gösterdiği tepkiyi ortaya koymak maksadıyla yükseltinin ağaç türü zenginliği, tür çeşitliliği ve rastlanma sıklığı üzerine etkileri araştırılmıştır. Gana’nın en yüksek dağı olan Afadjato dağı denizden yüksekliklerine göre 200-400 m, 400-600 m ve 600 m’nin üzeri olmak üzere üç yükselti basamağına ayrılmıştır. Kütlenin eteklerinden zirvesine doğru 5 kesit alınmış ve her bir 20 m yükselti artışında her bir kesitten 20 x 20 m2’lik 2’şer tane örnek alan alınmıştır. Göğüs yüksekliği çapı 5 cm’nin üzerinde olan bütün ağaçlar teşhis edilmiş ve ölçümleri alınmıştır. Ağaç türü zenginliği, göğüs yüzeyi alanı ve tür çeşitliliği bütün yükselti kademelerinde farklı bulunmuştur. Ağaçların rastlanma sıklığının yükselti arttıkça azaldığı tespit edilmiştir. Çalışmamızdan çıkarılan sonuçlara göre yükselti ile gerçekleşen değişimlerin daha iyi anlaşılması için daha farklı değişkenlerin denendiği çalışmaların yapılması gerektiği anlaşılmaktadır

Keywords

Yükselti, Ghana, Dağ, Tür zenginliği, Tropikal ağaç türleri

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