African Journal of Ecology and Ecosystems

African Journal of Ecology and Ecosystems ISSN 2756-3367 Vol. 11 (5), pp. 001-004, May, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Assessing soil micro-arthropods as bioindicators of oil pollution in a secondary rainforest, Rivers State, Nigeria

Samuel Okiwelu ¹*, Gbarakoro Tambeke¹ and Badejo Adetola²

¹Department of Animal and Environmental Biology, University of Port Harcourt, Port Harcourt, Nigeria.
²Department of Zoology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria.

Accepted 25 October, 2023

Abstract

Comparisons were made of the species richness and densities of soil micro-arthropods- (mites, collembolans) from a relatively undisturbed secondary forest and a nearby area, where there had been an oil spill, approximately 1 year before the commencement of the 2 yr study, May, 2007 to April, 2009. Soil samples were taken monthly with an 8.5 cm diameter bucket -type auger. Extraction was by the Berlese-Tullgren funnel. Identification was undertaken with the aid of standard keys and comparisons were made with type specimens. Mean Total Hydrocarbon (THC) values were 630 mg/kg (43.0 to 1000.0) and 10 mg/kg at the polluted and undisturbed habitats respectively. Among the mites, Cryptostigmata (Oribatids) were dominant in both undisturbed (69.85%) and polluted (74.25%) habitats; the least abundant were the prostigmates. Within the oribatids, Scheloribates spp., Galumnidae spp., Parallonothrus nigeriensis and Bichythermamia nigeriana were collected from both habitat types. In contrast, Mixacarus sp., Aunecticarus sp., Atropacarus sp., Bellidae sp., Cephalidae sp., Oppia sp., Basilobellidae sp., Epilohmaunia sp., Mesoplophora sp., Aecheogozettes magnus and Northrus lasebikani were restricted to the undisturbed habitat. In the Mesostigmata, only Parasiticidae sp . and Rhodacaridae sp. were found in both habitat types; Polyaspidae sp., Uropodidae sp. and Asca sp. were restricted to the undisturbed habitat. The Prostigmata, Bellidae sp. were collected from undisturbed and polluted habitats. Among Collembolans, Cryptophagous and Paranolla were found in both habitat types while Hypogastina, was restricted to the undisturbed habitat. Abundance and densities of mites and collembolans were respectively significantly reduced in the polluted habitat (p < 0.05; df = 9; F = 20.5; p 0.05; df = 9; F = 30.08). These findings are discussed within the context of the use of monitor (tolerant) and indicator (sensitive) species in bio-monitoring and assessment of oil pollution.

Key words: Soil mites, collembolans, oil pollution, densities, monitor/indicator species, rainforest, Nigeria.
 

African Journal of Ecology and Ecosystems ISSN 2756-3367 Vol. 11 (4), pp. 001-006, April, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Biopesticidal potential of hexane extracts from three plant species against bean weevil and maize weevil

O. O. Ogunsina¹*, M. O. Oladimeji² and L. Lajide¹

¹Department of Chemistry, Federal University of Technology, Akure, Ondo State, Nigeria.
²Joseph Ayo Babalola University, Ikeji-Arakeji, Osun State, Nigeria.

Accepted 18 November, 2023

Abstract

A study was conducted to evaluate the insecticidal action of hexane extracts of three locally available plants namely: Lantana camara (Verbenaceae), African nutmeg [Monodora myristica (Gaerth) Dunal] and Enuopiri [Euphorbia lateriflora, Schum and Thonner] against bean weevil Callosobruchus maculatus (F.) and maize weevil, Sitophilus zeamais) Motsch with response to the insect mortality. Results revealed that all test materials exhibited mortality action against bean weevil and maize weevil. African nutmeg extracts had greater mortality action against both the beans weevil (100%) and maize weevil (96%) after 24 h of treatment. Lantana extracts were observed to have moderate mortality effect; bean weevil (93%) and maize weevil (73.3%) while Enuopiri had average mortality effect; bean weevil (46.7%) and maize weevil (50%) all with extract concentration of 10 g/100 ml (extract/solvent). The overall results showed that bean weevil was much more susceptible to all the extracts than maize weevil, having recorded the height mortality rate.

Key words: Bean weevil, maize weevil, Lantana camara, African nutmeg, Enuopiri, mortality.

African Journal of Ecology and Ecosystems ISSN 2756-3367 Vol. 11 (3), pp. 001-012, March, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Impacts of exotic lantana camara L. on native riparian vegetation: A Study from the Nayar Region in the Garhwal Himalayas, Uttarakhand, India

Parveen Kumar Dobhal^1,2*, Ravinder Kumar Kohli² and Daizy Rani Batish²

¹Department of Botany, Government Degree College, Dakpathar, Vikasnagar, Dehradun – 248125, India.
²Department of Botany, Panjab University, Chandigarh - 160014, India.

Accepted 17 September, 2023

Abstract

Lantana camara L. (Verbenaceae), an exotic from tropical America, has invaded vast areas of forests surrounding Nayar River in Garhwal Himalayas (Uttarakhand, India). Several factors like high reproductive potential, absence of preferred predators, evergreen nature and sufficient moisture provided by river water favour extraordinary growth of L. camara in this area. In this study, the impact of L. camara invasion on basal area cover, density, frequency and abundance of various plant species was determined. Invasion was able to change the quality (composition, distribution) and quantity (growth in number and size) of different species in this region. The invasion was also found to have some relation with native-exotic nature and different plant habits (like tree and herbs) of local flora. As determined by various ecological indices, there was significant loss of species richness and diversity in invaded localities. In total, there was a 28.4% decrease in species richness of invaded localities. Excluding L. camara, nearly 63% loss of basal area of vegetation was recorded in the invaded localities compared to not invaded ones. There was also an impression that L. camara favoured exotics over endemic species in this riparian zone.

Key words: Invasion, Lantana camara, riparian, species richness, species diversity, Garhwal Himalaya.

African Journal of Ecology and Ecosystems ISSN 2756-3367 Vol. 11 (2), pp. 001-010, February, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

The impact of urbanization on vegetation cover in Nigeria’s Federal Capital Territory: A case study

Ujoh Fanan¹*, Kwabe Isa Dlama¹ and Ifatimehin Olarewaju Oluseyi²

¹Department of Geography and Environmental Management, University of Abuja, Nigeria.
²Department of Geography and Planning, Kogi State University, Anyigba, Nigeria.

Accepted 13 September, 2023

Abstract

Since Abuja became Nigeria’s Federal Capital Territory in 1976; it has been experiencing rapid expansion, urbanization and significant changes in its physical landscape. This study used Remote sensing and GIS techniques to identify, mark and measure the extent of change in the various land uses from the Landsat imageries of 1987 and 2001, and Nigeriasat-1 imagery of 2006. The study revealed that while built- up area increased, vegetation cover decreased at an alarming rate. Using population figures of the study area for 1987, 2001 and 2006, the Land Consumption Rate (LCR) and Land Absorption Coefficient (LAC) were determined. Increasing population and expansion in the Federal Capital City (FCC) resulted in land degradation including loss of vegetal cover, indiscriminate waste disposal, contamination of surface water, etc. now clearly visible in the FCC. In view of the important role that vegetation plays as a carbon sink, policy-makers are requested to strictly enforce the existing laws on afforestation and parks establishment and other measures, within and around the FCC in order to achieve a sustainable urban growth and development.

Key words: Urbanization, habitat fragmentation, land consumption rate, land absorption coefficient, landuse/cover change.