Variation in heavy metals bio-accumulation in fish organs in relation to water quality from Wasai reservoir, Kano State

Shehu Hussain Abubakar, Jan Beran, Aisha Ibrahim Dantiye, Mohammed Kabiru — Mon, 21 Apr 2025 00:00:00 +0000

A study was conducted to assess the levels of heavy metals such as Pb and Cd bioaccumulation in the liver and gills of fish species collected from Wasai reservoir covering two seasons. Physico-chemical parameters of the surface water were determined monthly for a period of 10 months (covering wet and dry seasons). Similarly, samples were collected from the muscles of African catfish (Clarias gariepinus) and Tilapia (Oreochromis niloticus) obtained from the reservoir. The water and fish samples were collected and analyzed for heavy metals using an atomic absorption spectrometer. Data obtained were analyzed using Analysis of Variance with Duncan’s New Multiple Range Test used to separate significant means at 5% level. The result obtained revealed significant difference (P≤0.05) in pH, DO and BOD with location and season. The levels of the heavy metals varied significantly in the water and fish species. The result showed a significant difference (P≤0.05) in heavy metal accumulation in the water body across the months. Cr level was highest in May 2019 (1.17 mg/L) and lowest in September 2018 (0.28 mg/L). The concentration of Pb was highest in April 2019 with a value of 0.136 mg/L and lowest in March 2019(0.016 mg/L). In the fish muscles, the highest concentration for Pb (0.055±0.005 mg/L) was found at station C in April 2019 while the highest levels of cadmium in the water samples (0.045±0/009 mg/L) was recorded in May 2019 at station B.

Superposed epoch analysis of relativistic electron flux depletion during moderate CIR storms

Mon, 21 Apr 2025 00:00:00 +0000

A superposed epoch analysis of radiation belt electron flux depletions during September 2012 - December 2018 identified 46 clear dropout events of duration 24 hours and which extended below L = 5. Of this number, 58% were associated with co-rotating interaction region (CIR) storms. The dropouts associated with CIR storms during SYM/H index - 80 nT intervals were energy dependent with depleted 1.8 MeV fluxes returning to pre-depletion levels after the storm, and true losses occurring for fluxes of higher energy electrons. However, the population of the source electrons (54 keV) increased during the same intervals while the 742 keV electrons population appeared to be driven by competing enhancement and loss processes. The highest depletion levels were recorded for electrons of energy 1.8 MeV at 4.6 L 4.9. A superposed epoch analysis showed that onset of 1.8 MeV flux depletions was triggered by substorm expansion phase and southward orientation of the field-aligned component of interplanetary magnetic field (IMF Bz). On the other hand, recovery of fluxes coincided with substorm recovery and IMF Bz northward reversal. Analysis of cosmic noise absorption data during a selected flux depletion event showed evidence of ionosperic precipitation.

Journal of Scientific Research and Development

Variation in heavy metals bio-accumulation in fish organs in relation to water quality from Wasai reservoir, Kano State

Superposed epoch analysis of relativistic electron flux depletion during moderate CIR storms