https://commons.ru.ac.za/vital/access/manager/Index en-us 5 https://commons.ru.ac.za/vital/access/manager/Repository/vital:45221 Wed 30 Mar 2022 12:24:30 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45204 Wed 24 Nov 2021 14:53:11 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45025 Wed 13 Apr 2022 12:03:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45073 Wed 06 Jul 2022 08:47:38 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:57262 Tue 27 Aug 2024 16:16:21 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45129 Tue 27 Aug 2024 11:16:52 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45224 Tue 16 Nov 2021 13:34:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45054 0.05), with the overall population growth curve being best described as L(t) = 697.15(1-e-0.06(t-6.30)). Males matured at a slightly larger size than females, however, no significant differences were observed (LRT, p > 0.05). The length- and age- at-50% maturity was 330 mm (FL) and 5.73 years for the full population, respectively. Histological analyses showed that Oplegnathus conwayi are asynchronous spawners with a gonochoristic reproductive style. Macroscopic staging and gonadosomatic index results indicated a protracted spawning season for Oplegnathus conwayi, with a peak in spring. A survey was designed and disseminated to collect FEK on the biology and population status of Oplegnathus conwayi and human dimension information on South Africa’s spearfishery. A total of 103 survey responses were received, of which 94 were regarded as specialised (spearfishers who had greater experience, skill and avidity, and maintained spearfishing as an important component of their lifestyle) spearfishers. Based on the responses of the specialist spearfishers, the top four main species caught by spearfishers from this survey were Seriola lalandi (13.9%), Pachymetopon grande (11.7%), Oplegnathus conwayi (11.4%) and Sparodon durbanensis (11%), and the majority of respondents indicated that there had been no changes in abundance, size and catches of these species in the years that they had been spearfishing. Respondents indicated that Oplegnathus conwayi are most commonly targeted in the Eastern Cape and are found at depths of up to 40 m. Respondents also indicated that there may be a seasonal onshore (Summer/Winter) and offshore (Summer/Winter) migration with year-round spawning and a peak in November, December and January. The incorporation of spearfishers into the data collection, both through the collection of specimens and their FEK, was beneficial to this study. Besides providing samples from a broader geographical range than the primary collection area, the collaboration with spearfishers has promoted the inclusion of this group into the management system. The findings of this study also suggest that FEK data can be more reliable if the concept of recreational specialisation is incorporated into data collection. While the FEK suggested that the population was stable, a stock assessment is necessary to fully understand the population status and implement management strategies. Nevertheless, the key life history characteristics (slow growth and late maturation) observed in this study are characteristic of species that is vulnerable to overexploitation, and thus the precautionary approach should be applied. The reproductive information collected in this study has provided information for the implementation of an appropriate size limit regulation for Oplegnathus conwayi. Here, a minimum size limit of 400 mm TL, which corresponds approximately with the length-at-50% maturity of 330 mm FL, would be appropriate to allow fish to mature and spawn, and reduce the likelihood of recruitment overfishing. Reduction in the bag limit from five to two fish per person per day may also be appropriate as a precautionary measure until a stock assessment has been completed. Finally, the incorporation of stakeholder into biological collection and the use of FEK may be a useful approach for other data deficient species and in countries with limited resources for ecological research.]]> Thu 29 Sep 2022 14:29:54 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45266 Mon 15 Nov 2021 15:27:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45264 Mon 15 Nov 2021 15:06:44 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45071 500 mg/L), increased viscosity, inability to flocculate microalgal cells, a rhamnolipid content of 32%, and a higher surface-activity. Based on these results, Bacillus strain ECCN 41b was rationalized to produce anionic EPS with potential application in metal or oil recovery. In addition to EPS production, the bacteria Planococcus strain ECCN 45b and Exiguobacterium strain ECCN 46b appeared pigmented. Based on partial characterization using UV/Vis spectrophotometry, thin-layer chromatography, FTIR, and NMR, the pigments produced by these two strains appeared to be identical and were tentatively identified as ketocarotenoids. This study successfully demonstrated the importance of EPS production and formation of MaB-flocs in the MLSS from HRAOP of an IAPS treating domestic sewage. It is evident that increased settleability of the biomass does contribute to the reported efficiency of wastewater treatment by IAPS and would reduce both total suspended solids (TSS) and chemical oxygen demand (COD). In addition, demonstration that this biomass contains products of value such as carotenoids and EPS with potential for commercial use strengthens the idea of using IAPS as a platform technology for innovation of the wastewater treatment process to a biorefinery.]]> Mon 14 Feb 2022 15:19:49 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45041 Fri 18 Feb 2022 14:44:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45220 Fri 08 Jul 2022 09:22:31 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:45060 Fri 01 Jul 2022 12:49:32 SAST ]]>