Effects of human disturbance and altitudinal gradient on myriapod species richness and abundance at Mount Kala, central Cameroon

Abstract

Myriapods are remarkably diverse and encompass many endemic species, yet they remain poorly studied in Cameroon. We investigated the influence of anthropogenic activities on myriapod assemblage structures along an altitudinal gradient at Mount Kala. Myriapods were collected by pitfall trapping, hand sorting and litter sifting in four altitudinal levels and habitats (820 m, 920 m, 1 020 m and 1 120 m above sea level) from November 2017 to July 2018. A total of 1 131 individuals from 58 species in 3 classes (Diplopoda, Chilopoda and Symphyla), 36 genera and 17 families were recorded at Mount Kala. The Diplopoda was the most abundant and diverse class (94.69% and 49 species), followed by Chilopoda (4.51% and 8 species) and Symphyla (0.80% and 1 species). Aporodesmus gabonicus Lucas, 1858 and Karkinikus colonus Attems, 1914 were the most abundant species in the study site. Along the altitudinal gradient, the myriapod species richness decreased in anthropised areas (820 m to 920 m above sea level), reached a maximum in transitional forest (920 m to 1 020 m above sea level) and slightly decreased within the submontane forests (1 020 m to 1 120 m above sea level). Myriapod abundance followed the same trend. However, our results also indicate a high species richness turnover observed between altitudinal levels suggesting that most species are adapted to a particular habitat and could serve as indicators of environmental changes. Accordingly, this study demonstrates a negative relationship between anthropisation and myriapod diversity, as well as the implications towards the management of the Mount Kala forest.

Keywords: myriapod, diversity, abundance, elevational gradient, Cameroon