https://commons.ufh.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26750 Wed 20 Jul 2022 08:42:27 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:39298 Wed 12 May 2021 23:59:26 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20497 Wed 12 May 2021 23:45:03 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10678 Wed 12 May 2021 23:17:04 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4722 Wed 12 May 2021 23:15:56 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20407 Wed 12 May 2021 23:11:59 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4889 Wed 12 May 2021 23:01:32 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20626 8 ha). Small wetlands (< 2 ha), by contrast, are often overlooked and unprotected due to the lack of detailed inventories at a scale that is appropriate for their inclusion. The main aim of this study was to determine if remote sensing (RS) and Geographical Information System (GIS) techniques could detect changes in small, ephemeral wetlands within areas under different management regimes in the Nelson Mandela Bay Metropole (NMBM) at different time intervals. Further, to explore the potential of hyperspectral remote sensing for the discrimination between plant species and to see if differences could be detected in the same species within two areas different management regimes. Four SPOT satellite images taken within a 6-year period (2006-2012) were analysed to detect land cover land changes. Supervised classification to classify land cover classes and post-classification change detection was used. Proportions of dense vegetation were higher in the conservation area and bare surface was higher outside that conservation area in the metropolitan open space area. Statistical tests were performed to compare the spectral responses of the four individual wetland sites using Normalized Difference Vegetation Index (NDVI) and red edge position (REP) .REP results for conserved sites showed significant differences (P < 0.05), as opposed to non-conserved ones. By implication, wetland vegetation that is in less degraded condition can be spectrally discriminated, than the one that is most degraded. Field spectroscopy and multi-temporal imagery can be useful in studying small wetlands.]]> Wed 12 May 2021 22:50:34 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4708 Wed 12 May 2021 22:25:01 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4890 Wed 12 May 2021 22:20:35 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4540 Wed 12 May 2021 20:57:48 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5090 Wed 12 May 2021 20:55:54 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1120 Wed 12 May 2021 20:54:28 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20438 Wed 12 May 2021 20:34:22 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20563 10 000 cells ml-1) of several different groups were recorded from the middle reaches of the estuary to the tidal limit. Diatoms were the dominant group during increased freshwater inflow (at mean daily flow rate of 2.14 m3 s-1) and low DIP levels, whereas flagellates were generally the dominant group during reduced flow and under higher nutrient levels. Although the different tidal stages had no effect on phytoplankton biomass per se, it did support co-existance between phytoplankton groups. This was noted during the spring ebb tide in September 2012 (i.e. flagellates, diatoms and dinoflagellate) and in February 2013 (i.e. dinoflagellates, diatoms and chlorophytes). Phytoplankton blooms have become persistent in the middle to upper reaches of the estuary where chlorophyll-a was > 20 µg l-1 and cell density exceeded 10 000 cells ml-1; a situation not reported in previous studies. The Motherwell Canal was and still is the main source of nitrogen (generally in the form of ammonium) to the estuary, whereas the Swartkops River is still the primary source of phosphorus to the estuary. Since the stormwater canal services the large residential area of Motherwell where leaks in the sewer system, the dumping of night soil buckets, and faulty pumps are often reported, polluted discharges from the Motherwell Canal can enter the canal at any given point. In contrast to the canal, DIP loading from the Swartkops River to the estuary generally occurred under conditions of low flow, whereas nitrogen showed no apparent relationship. Faecal bacteria originating from the Motherwell Canal had the most profound effect on the bacteriological status in the middle reaches of the estuary, whereas the Swartkops River had an intermediate effect due to bacteria die-offs occurring between the point of release from the WWTW to the riverine reaches and the tidal limit of the estuary. Nevertheless, Escherichia coli and enterococci levels are still high, especially in the summer months rendering the estuary unsafe for recreation during this season. Historical data on trace metals in the water column were limited and thus observations from the present study could not be concluded with much confidence. However, preliminary data suggest that levels of copper, zinc, iron and cadmium have increased by at least 90% in the estuary, at the tidal limit of the estuary and in the Markman and Motherwell canals. High inputs of nutrients, trace metals and faecal bacteria to the estuary from land-use activities indicate the necessity for remedial actions with the main objective being to conserve and protect the estuary’s recreational, ecological and economic functions.]]> Wed 12 May 2021 20:10:47 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5558 Wed 12 May 2021 19:49:57 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10679 1.1 percent Ro, 120ºC). The TOC content is consistently high within the Whitehill (exceeding industry requirement of 2 percent), attaining maximum of 7.3 percent. The highest yields of free and desorbed gas, especially methane, were emitted within this formation (S1 and nC1 peaks); mostly within its dolomitic units. In addition, dissolution porosity within dolomite units of the Whitehill Formation was identified as the predominant type of porosity. Thus, it is deduced that the dolomitic units of Whitehill Formation potentially contain the greatest volumes of free gas. HI values attain maximum of 25 mg HC/g TOC, whereas the OI values 26 mg CO2/g TOC. Such low HI and OI values are typically attributed to the dominance of Type IV kerogen, and consistent with overmaturity. Open pyrolysis (GC) show the main the chemical compound of the organic matter to be m-p-xylene, consistent with a mix of Type III, Type I/II and Type IV kerogen. Lithologically, the Whitehill Formation is composed of ~ 35 quartz, 13 percent feldspar, 26 percent illite and ~ 23 percent dolomite with variable amounts of pyrite. The dominance of quartz is directly proportional to the brittleness of the rock. Thus it can be deduced that the Whitehill Formation is relatively brittle and therefore fraccable. Burial trends indicate increasing depth (from ground level) to the top of the Whitehill Formation towards the south and south-eastern portion of the basin. It is in the southern region where thicknesses of this black shale exceeding 50m occur at depths more than 1500m; 1000m beneath fresh water aquifers. It therefore concluded that Whitehill Formation in the southern portion of Karoo Basin, but away from the thermo-tectonic overprint of the Cape Orogeny, is the most probable shale gas reservoir in South Africa.]]> Wed 12 May 2021 19:46:03 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4272 Wed 12 May 2021 19:24:38 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4546 Wed 12 May 2021 19:17:44 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5958 Wed 12 May 2021 19:12:45 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4154 Wed 12 May 2021 19:07:50 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:28591 Wed 12 May 2021 19:06:38 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4711 Wed 12 May 2021 18:59:13 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:27565 Wed 12 May 2021 18:53:20 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5176 Wed 12 May 2021 18:52:34 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4146 Wed 12 May 2021 18:41:14 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4152 Wed 12 May 2021 18:36:22 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26652 850 oC), it is found that even though their crystalline quality is preserved, their morphology is significantly affected, regardless of annealing ambient. Furthermore, in the near surface regions of annealed ZnO nanorods it is found that the Zn/O stoichiometric ratios deviate from unity. Specifically, oxygen vacancies form within the first 100 nm from the sample surface. Further from the surface, the material is deficient in Zn. It is deduced from XPS and AES that the ambient affects the activation rate of intrinsic defects. Furthermore, the only extrinsic defects that are affected by thermal treatment are found to be H-related defects. At high annealing temperatures (300 oC to ~700 oC), H-related defects are removed, and this removal process is found to affect significantly the RT luminescence properties of ZnO nanorods. Specifically, hydrogen passivates vacancy-related defects, depending on the thermal treatment. PL spectroscopy is used to follow this passivation effect as a function of annealing temperature, which causes an initial quenching followed by an enhancement of the green and the red luminescence, regardless of the ambient. Finally, the green luminescence that arises following annealing above ~800 oC is assigned to Zn vacancy-related defects, while the red luminescence that dominates the visible band of ZnO nanorods upon annealing between 400 oC and 600 oC is suggested to be due to oxygen vacancy-related defects.]]> Wed 12 May 2021 18:36:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4548 Wed 12 May 2021 18:32:45 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5092 Wed 12 May 2021 18:15:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5579 Wed 12 May 2021 18:14:53 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:21055 Wed 12 May 2021 18:12:23 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4274 Wed 12 May 2021 17:52:49 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26752 Wed 12 May 2021 17:42:52 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5555 Wed 12 May 2021 17:41:38 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20410 Wed 12 May 2021 17:40:48 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4149 Wed 12 May 2021 17:35:42 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5089 Wed 12 May 2021 17:33:31 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9709 Wed 12 May 2021 17:22:24 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26411 Wed 12 May 2021 17:14:23 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10445 Wed 12 May 2021 16:51:02 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:21121 Wed 12 May 2021 16:50:15 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4723 Wed 12 May 2021 16:40:15 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:27993 Wed 12 May 2021 16:38:25 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20828 Wed 12 May 2021 16:21:07 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5563 Wed 12 May 2021 16:14:42 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5931 Wed 12 May 2021 16:04:52 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10551 Wed 12 May 2021 16:01:06 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:24324 Wed 12 May 2021 15:55:35 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4893 Wed 12 May 2021 15:50:10 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4165 Wed 12 May 2021 15:45:50 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:40362 Wed 12 May 2021 14:39:19 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:40361 Wed 12 May 2021 14:37:59 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:41974 Wed 12 May 2021 13:45:22 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:39616 Tue 07 May 2024 11:15:41 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5087 Thu 13 May 2021 13:12:25 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20674 Thu 13 May 2021 12:45:08 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5923 Thu 13 May 2021 08:22:51 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4161 Thu 13 May 2021 08:18:59 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20429 Thu 13 May 2021 07:20:18 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4153 Thu 13 May 2021 07:14:07 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:27718 Thu 13 May 2021 07:03:47 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4720 Thu 13 May 2021 06:50:13 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4891 Thu 13 May 2021 06:39:06 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5920 Thu 13 May 2021 06:26:01 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4151 Thu 13 May 2021 06:08:57 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5556 Thu 13 May 2021 06:07:57 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4707 Thu 13 May 2021 05:38:41 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20767 Thu 13 May 2021 05:29:07 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4715 Thu 13 May 2021 05:17:52 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20979 Thu 13 May 2021 05:17:39 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10731 Thu 13 May 2021 05:01:42 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4786 Thu 13 May 2021 05:01:32 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5557 Thu 13 May 2021 04:57:39 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:6051 Thu 13 May 2021 04:55:50 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4712 Thu 13 May 2021 04:53:15 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:39296 Thu 13 May 2021 04:47:11 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:27944 0.05) to T3. The dressing percent of T1 was significantly different (P<0.05) from T2 and T3 which were similar to each other, with T2 having the highest dressing percentage (78, 2 percent) and T1 having the lowest DP percent (66 percent). The breasts in T2 were significantly higher and different (P<0.05) from both T1 and T3 which were similar to each other. The drumsticks in T3 were significantly different (P<0.05) from T1 while they were similar to T2 with values with T2 having highest values. After 45 minutes of slaughter, a significant difference (P<0.05) was observed in L⃰ among all treatments. In redness (a⃰), T3 was significantly different from T1 but was similar to T2 and all treatments in this study exhibited a darker red meat, with T3 muscles exhibiting darker red colour than the other treatments. Similar results were observed in yellowness (b⃰), where the breast muscles from T3 were more yellow than the other treatments. After 24 hours of slaughter, T2 L⃰ values were significantly different (P<0.05) from both T1 and T3 which were similar to each other. It was also found that the broiler chickens given diet with no T. molitor L inclusion (T1) had lower values of BW, FI, ADG and FCR throughout the experiment than those that were in T2 and T3 with 5 percent and 10 percent T. molitor L inclusion levels, respectively. However, it was also found that although broilers with 5 percent T. molitor L inclusion (T2) in their diet had high ABW and ADG than the broilers with 10 percent T. molitor L inclusion (T3), the T3 birds compared favourably to T2 birds as they required low feed intake to reach the same slaughter weight due to high FCR. It was, therefore, concluded that T. molitor L meal can be incorporated into the diets of broilers to produce heavy birds either at 5 or 10 percent. However, although 5 percent T. molitor L inclusion yields heavier carcasses, the 10 percent T. molitor L inclusion compared favourably to 5 percent inclusion since it required low feed intake to reach the same slaughter weights and there were slight differences on meat quality attributes between the two treatments.Thus T. molitor L at 10 percent inclusion levels was the best inclusion level to enhance broiler growth performance, carcass yield, meat yield and meat quality.]]> Thu 13 May 2021 04:45:31 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4539 Thu 13 May 2021 04:42:43 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4162 Thu 13 May 2021 04:21:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:21075 Thu 13 May 2021 04:02:07 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26831 Thu 13 May 2021 03:46:25 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5086 Thu 13 May 2021 03:41:37 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20417 Thu 13 May 2021 03:31:19 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4542 Thu 13 May 2021 03:30:48 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:27712 Thu 13 May 2021 03:29:07 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4716 Thu 13 May 2021 02:40:49 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20360 Thu 13 May 2021 02:33:04 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:27983 Thu 13 May 2021 02:28:06 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26764 Thu 13 May 2021 02:18:22 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26648 Thu 13 May 2021 01:56:33 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20976 Thu 13 May 2021 01:37:18 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:20548 Thu 13 May 2021 01:34:40 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5085 Thu 13 May 2021 01:29:14 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5379 0.8°C/decade) increasing water temperatures. These changes are thought to drive further changes to the biology of fishes. It is therefore critical to provide baseline biological information and to identify the impacts of exploitation and warming on the biology of southern Angolan fishes. Pomatomus saltatrix is a warm-temperate marine fish species that forms an important component of fisheries throughout its broad distribution. P. saltatrix is a migratory predator that displays variable growth and maturity schedules. Typically it is heavily targeted in a range of coastal fisheries of Angola and is therefore an ideal candidate to study the biological impacts of exploitation and climate change. The aim of this study was to provide the first description of P. saltatrix biology in Angola and examine recent changes of the species biological parameters in an attempt to uncouple fishery driven from climate driven changes. Samples of P. saltatrix were collected monthly using standardised biological methods from June 2005 to December 2006 (period 1) and from June 2012 to February 2013 (period 2). The average (508mm – 1st period, 462mm – 2nd period) and maximum (760mm – 1st period, 746mm – 2nd period) size of P. saltatrix was smaller during the second period to suggest selective overharvesting of large individuals by developing fisheries. Angolan P. saltatrix grew very rapidly in their first year and thereafter, relatively slowly when compared to other populations globally. However, fish grew faster (ω = 103 – 1st period, ω = 124 – 2nd period), matured at a larger size (303mm - 1st period, 336mm - 2nd period) and younger age (0.83 years - 1st period, 0.67 years – 2nd period) during the second period. Peaks in reproductive activity remained similar (November) during both periods but a temperature anomaly appears to have influenced spawning during period 2. Sardinella aurita was the dominant prey during both periods but a greater dependence upon mugilids was observed during the second period. Although the changes in life history were not statistically significant, the faster growth observed during period two could be attributed to both increasing temperature and/or exploitation. Fishes generally grow faster, mature smaller and attain a smaller maximum size in warmer temperatures. Fisheries targeting small and large specimens of a species (as observed in this study) largely have the same impacts as ocean warming. With rapidly increasing water temperatures and exploitation rates, faster growth and earlier maturation of P. saltatrix populations will mitigate the impacts of exploitation in the short-term. However, the sustainability of Angola’s P. saltatrix stock is questionable as phenotypic adaptation will have a limited thermal scope and overexploitation will, like in all fisheries, negatively influence recruitment. Ultimately, strict monitoring, regulation and control will be necessary to ensure the sustainability of the P. saltatrix resource in Angola as it continues to face increasing anthropogenic and environmental pressures. Management guidelines and future research suggestions are therefore outlined with reference to the results of analyses conducted during this study.]]> Thu 13 May 2021 01:19:58 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:6050 Thu 13 May 2021 01:12:40 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5433 Thu 13 May 2021 01:12:11 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26636 Thu 13 May 2021 00:51:57 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4717 Thu 13 May 2021 00:49:10 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5932 Thu 13 May 2021 00:44:05 SAST ]]>