Trends in macrobenthal biotypes of Imo River in a Nigerian Delta region
Journal Title: Journal of Biodiversity and Environmental Sciences (JBES) - Year 2013, Vol 1, Issue 4
Abstract
Dynamics in macrobenthos abundance and diversity in sand-mined Imo River in Etche, South-eastern Nigeria has been investigated. While 14 representative species, comprising 3 classes (insect, oligochaeta, and gastropoda) were earlier identified in 2003, 9 species of these classes and 5 species comprising 2 classes only (insecta and oligochaeta) were identified in 2009 and 2010, respectively. Though Margalef’s diversity had increased from 1.67 in 2003 to 2.30 in 2009, it sharply decreased to 0.69 in 2010. Over these periods, entomofauna (class insecta) predominated the faunal assemblages with 8 species from 6 families in 2003, 7 species from 5 families in 2009, and 3 species from 2 families in 2010. Significant spatial variance inequality in macrobenthos abundance was observed at P<0.05 [F(240.54)>Fcrit(3.89)]. Further, there was variance inequality in means of macrobenthos abundance between 2003, 2009, and 2010 [F(6.54)>Fcrit(4.03)] at P<0.05. A further structure detection of mean difference revealed that inequality was most accounted for by the larva of the insect- Sialis luteria that was conspicuously absent in the 2009 and 2010 identifications. There was generally high interspatial community dissimilarity, except an average similarity of 50% (0.50) recorded between locations 2 and 6, and 3 and 7 in 2009, as well as 50% between locations 1 and 3 and 2 and 6, and 67% between locations 2 and 7, and 3 and 7 in 2010. Benthic sediments were slightly acidic (6.95±0.01), with low nitrate (0.48±0.03), phosphate (0.72±0.04), and sulphate (44.35±1.57) concentrations. We suspect declining macroinvertebrate diversity and abundance in the river, and that ongoing anthropogenic perturbation (sand mining) contributes immensely to this paucity through the excavation and removal of benthal nutrients necessary for a thriving and diverse sediment community.
Authors and Affiliations
Dike Henry Ogbuagu, John Didacus Njoku, Adedolapo Abeke Ayoade
Keywords
Related Articles
- EP ID EP37186
- DOI -
- Views 214
- Downloads 0
Microhabitats of Leaf-Dwelling Pholcid Spiders (Araneae: Pholcidae) in Mount Mupo, Marawi City, Philippines
Microhabitat utilization is an important factor for species diversification. This study examined the microhabitat utilization of leaf-dwelling pholcids. The occurrence of 241 collected samples showed different degrees of...
Population Analysis via Fluctuating Asymmetry in the wings of Culex quinquefasciatus Say from selected breeding sites in Iligan City, Philippines
Fluctuating asymmetry (FA) refers to the unequal bilateral sides of an organism. It occurs when an individual is unable to undergo identical development on both sides of a bilaterally symmetrical trait. It measures the...
Determine of nutritive value of dried citrus pulp various using in situ and gas production techniques
Citrus pulp is an important by-product for sub-tropical and tropical ruminant animal production. In this study two wethers (38 ± 1.5) were used insitu method. Wetheres equipped with ruminal cannulas. Ruminal DM and CP...
The Effect of Application of Different Levels of Axing and Gibberellins at Different Growth Stages on Quantitative and Qualitative production Components of Field Bean
This experiment was carried out in Shahid Salemi experimental field of Islamic Azad University of Ahvaz, In Northeast of Ahvaz at latitude 31°20´ N and longitude 48°40´ E and 22.5 m above the sea level in the summer of...
Investigation of structural distribution of gold mineralization in “Sefidsang” area (SE-Zahedan, Iran)
Sefidsang area is located 70 km to south east of Zahedan. This area is located in the eastern Iran flysch zone. It has been composed of Ophiolithic rocks and Flysch sediments. Zahedan granitoides of Oligocene age have...