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This study was performed to evaluate the change in seasonal abundance and distribution of individual mosquito vectors (Culex, Anopheles, and Aedes) in relation to the climatic factors in Eastern Province, Saudi Arabia, for the study period of 2014. The association between mosquito abundance and environmental parameters was investigated using bivariate and multivariate analysis. The study showed the range of temperature and relative humidity required for individual mosquito larvae abundance varies for Culex, Anopheles, and Aedes. However, no variation was observed in the range of temperature and relative humidity required for the abundance of adult Culex and Anopheles. The results revealed a negative relationship between mosquito larval/adult abundance and temperature (Total number of larva/adult is 671/11 in July, While it is 2462/221 in January). There is a link between relative humidity and rainfall, as the three climatic factors together were responsible for 33.1% (R2 = 0.331), 54.6% (R2 = 0.546), and 86.6% (R2 = 0.866) of the variance on Culex, Anopheles, and Aedes larvae, respectively. The effects of the three climatic parameters of temperature, relative humidity, and rainfall on mosquito larval and adult abundance were discussed. In addition, influences of other environmental factors on larval/adult mosquito distribution and abundance were also explained.

To date, only a handful of bacterial strains that can independently degrade and utilize benzo[a]pyrene (BaP) as the sole carbon source has been isolated and characterized. Here, three new bacterial strains—JBZ1A, JBZ2B, and JBZ5E—were isolated from contaminated soil and, using 16S rRNA sequencing, were identified as Brad rhizobium japonicum, Micrococcus luteus, and Bacillus cereus, respectively. The growth ability of each individual strain and a consortium of all strains in the presence of BaP (4–400 µmol·L−1, pH 7, 37 °C) was identified by the doubling time (dt). The results illustrate that dt decreased with increasing BaP concentrations for individual strains and the consortium. The optimum growth conditions of the consortium were 37 °C, 0.5% NaCl (w/v), and pH 7. Under these conditions, the degradation rate was 1.06 µmol·L−1·day−1, whereas that of individual strains ranged from 0.9 to 0.38 µmol·L−1·day−1. B. cereus had the strongest contribution to the consortium’s activity, with a degradation rate of 0.9 µmol·L−1·day−1. The consortium could also remove BaP spiked with soil but at a lower rate (0.01 µmol L−1.day−1). High-performance liquid chromatography–high-resolution tandem mass spectrometry permitted the detection of the metabolites of these strains, and a biodegradation pathway is proposed.