Environmental effects of crude oil spill on the physicochemical and hydrobiological characteristics of the Nun River, Niger Delta

Oil spill pollution has remained a source of several international litigations in the Niger Delta region of Nigeria. In this paper, we examined the impacts of small recurrent crude oil spills on the physicochemical, microbial and hydrobiological properties of the Nun River, a primary source of drinking water, food and recreational activities for communities in the region. Samples were collected from six sampling points along the stretch of the lower Nun River over a 3-week period. Temperature, pH salinity, turbidity, total suspended solids, total dissolved solids, dissolved oxygen, phosphate, nitrate, heavy metals, BTEX, PAHs and microbial and plankton contents were assessed to ascertain the quality and level of deterioration of the river. The results obtained were compared with the baseline data from studies, national and international standards. The results of the physicochemical parameters indicated a significant deterioration of the river quality due to oil production activities. Turbidity, TDS, TSS, DO, conductivity and heavy metals (Cd, Cr, Cu, Pb, Ni and Zn) were in breach of the national and international limits for drinking water aquatic health. They were also significantly higher than the initial baseline conditions of the river. Also, there were noticeable changes in the phytoplankton, zooplankton and microbial diversities due to oil pollution across the sampling zones.<br/

The recruitment patterns of two palaemon shrimps and some physico-chemical characteristics in the River Nun Estuary, Nigeria

Therecruitment patterns of two palaemon shrimps, Nematopalaemon hastatus and Palaemon maculatus in the Nun River Estuary was studied for one year (2005-2006). In addition some physical and chemical parameters were measured to evaluate the characteristics of the fishery. The data obtained from the study showed that monthly surface water temperature values ranged from 210C (March-April) to 240C (July – September), salinity values from 9.0 Psu (July) to (21.3 Psu) (February). PH values ranged from 6.9 (December) to 8.2 (March). Rainfall values ranged from 30 mm (January) to 580 m (September). The main spawning season was between July and September. The lowest spawning activity occurred in November and December for both species. Both species were present all year round. N. hastatus was highest in September (63%) and lowest in November (57%), while P. maculatus was highest in November (43%) and lowest in September (37%). However, there was no significant difference in the monthly catch composition for both species. The seasonal spawning activity showed that spawning occurred all year round for both species. Peak spawning activity occurred in September for N. hastatus, while that of P. maculatus was August and September. The largest carapace length recorded was 14 mm for N. hastatus, while that of P. maculatus was 12 mm. More spawners were caught during the rainy season than dry season (Tcas = 3.04; Ttab = 0.025(5) = 2.571). Recruitment occurred all year round for both species, each with two peaks.Keywords: Shrimps, spawning activity, physico-chemical characteristics, River Estuary, Nigeri

Survival response of Oreochromis niloticus Linnaeus, 1758) fingerlings exposed to various concentration of perfkthion

No Abstract.Animal Production Research Advances Vol. 3 (4) 2007: pp. 319-32