TITLE:
Spatiotemporal Variation of Benthic Macroinvertebrates in Some Tropical Forest Streams of the Nyong Catchment (Cameroon)
AUTHORS:
Jean Dzavi, Samuel Foto Menbohan, Blaise Rollinat Mboye, Mathias Nwaha, Eric Belmond Biram à Ngon
KEYWORDS:
Benthic Macroinvertebrates, Environmental Variables, Faunistic Diversity, Taxonomic Richness, Biotypology, Tropical Forest Streams, Cameroon
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.12 No.7,
July
18,
2022
ABSTRACT: With the aim of assessing the benthic
macroinvertebrates’ diversity, a study was carried out in some tropical forest streams of
the Nyong River catchment in Cameroon from February 2019 to February 2020. A
total of 167 samples were carried out from 13 stations during 13 months. Some
environmental variables were measured. These parameters varied more or less
from station to station but significantly at the temporal level. In this study, 13,690 benthic
macroinvertebrates belonging to 4 phyla, 7 classes, 16 orders and 93 families
were collected. The benthic macroinvertebrates were more abundant and more
diversified in the stations whose waters are well oxygenated and present a
moderate current compared to the stations with a very weak current. The diversity varied
significantly from 1.33 ± 0.14 bits/ind to 2.00 ± 0.35 bits/ind and the high
values were found in stations with multiple substrates and well-oxygenated
waters. Temporally, the diversity varied significantly from 1.10 ± 0.16
bits/ind in NM sampling station in February 2020 to 1.87 ± 0.1 bits/ind in the OB sampling station in September. In addition, the settlement was more
abundant during the short dry season, more precisely during the month of August (1471 individuals) but richer
during the long dry season during the month of February (54 families). The
distribution of the abundances of the benthic fauna in the different stations
made it possible to identify five typological groups using the
rarefaction curves, the ascending hierarchical
classification and the principal component analyses. Each of these five groups
is characterized by a specific taxonomic richness, composition and abundance.