Malaria parasites are transmitted in nature through the bites of female Anopheles mosquitoes. However, the vector distribution varies in time and space. This study aimed to determine the species composition, abundance and climatic factors influencing Anopheles mosquitoes in Anambra East Local Government Area of Anambra State, Nigeria from October 2016 to September 2017. Adult Anopheles mosquitoes were collected from indoor and outdoor locations using Pyrethrum Knockdown Collection (PKC) and Human Landing Catch (HLC) Methods respectively. Anopheles mosquito larvae were collected using dipping method. Morphological identification of Anopheles species was carried out using standard identification keys. Climatic data was obtained from Nigerian Meteorological Agency Office in Anambra State. A total of 8181 female Anopheles mosquitoes which comprised 4127 (50.4%) larvae and 4054 (49.6%) adults were collected (P > 0.05) in the study. Four Anopheles species: An. gambiae s. l (70.1%), An. funestus group (18.2%), An. moucheti (6.3%) and An. nili (5.4%) were identified (P < 0.05). In the study area, 2608 (31.9%), 3025 (37.0%) and 2548 (31.1%) Anopheles mosquitoes were collected from Aguleri, Igbariam and Nsugbe respectively; with 100% species overlap. In each selected selected town, the Simpson’s index of diversity was ~2 and Shannon-wiener diversity was ~1. Only An. gambiaes l showed varied seasonal abundance with wet season contributing 67.9% and dry season 32.1% of the overall An. gambiaes. l collection (P < 0.05). The correlation between rainfall and An. gambiae s. l. abundance was significantly strong (r = 0.66; P < 0.05). No significant correlation was found between Anopheles species abundance and temperature as well as relative humidity. The study revealed the preponderance of four Anopheles species: An. gambiae s. l., An. funestus, An. moucheti and An. nili; and rainfall is the only climatic factor that causes temporal change in the abundance of one of the species, An. gambiaes. l. in the study area. Keywords: Anopheles mosquitoes, abundance, temperature, rainfall, relative humidity

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Studies reveal that not up to 50% of earthworm species have been described in the world and the understanding of earthworm diversity is finite in most countries including Nigeria. The study was aimed at evaluating the diversity of earthworms and environmental factors affecting their abundance. Earthworms were collected from three (3) different sampling locations in Nnamdi Azikiwe University, Awka. Descriptive statistics and estimation of species abundance, dominance and diversity were used to analyze the data obtained from the study. From the study, four (4) species of earthworms were identified and recorded from the three sampling locations. Eudrilus eugeniae (54.9%) was the most abundant species followed by Hyperidrilus africanus (20.3%), Libyodrilus violaceous (19.6%) and Alma millsoni (6.3%) with the least abundant species. The result of the diversity indices showed Science village (1.13) as the most diverse habitat followed by Emelda hostel (0.86) and Boys’ hostel (0.84) with the least diversity of species. Soil pH ranged from 2.25 to 4.06 and total organic matter ranged from 14.10 to 16.36%. Soil temperature was uniform with an average value of 27°C for the three sampling locations. The soil moisture content ranged from 11.19 to 14.12%. The conductivity recorded the lowest value (25.60μS/cm) in Emelda Hostel and highest value (111.8 μS/cm) in Science village. The study provided understanding into the patterns of earthworm populations in Nnamdi Azikiwe University, Awka and the need for the conservation of earthworm diversity. Better understanding about habitat and living conditions of earthworms is required to provide suitable and enhanced production of vermicompost in different geographic conditions.

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Diseases caused by contaminated water consumption are among the leading causes of death in children, the elderly, and people who are immunocompromised. Hence there is an important need to ensure that drinking water sources are free from pathogens that can endanger the health of consumers. This study was undertaken to investigate the influence of seasonal changes on the bacteriological distribution of the Obibia stream. A total of 30 water samples (500 ml each) were collected for the study at rainy and dry seasons for a period of May to July 2015 and December 2015 to Feb 2016, respectively. Bacteria present in the water samples were isolated and characterized using 16s rDNA sequencing. Total heterotrophic aerobic bacterial counts were determined using standard microbiological biochemical procedures. Their frequencies of occurrence were also determined. Total heterotrophic aerobic bacterial counts (THABC) were significantly higher (P=0.039) > total coliform count > fecal coliform counts > Salmonella -Shigella counts > Vibrio counts throughout the periods of sampling in the wet season, with the highest counts obtained in July. THABC was also significantly higher (P = 0.018) than other examined bacterial groups and had its peak in January. Bacterial genera present in the examined samples were identified as Shigella, Salmonella,