https://vital.seals.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://vital.seals.ac.za/vital/access/manager/Repository/vital:71911 Wed 27 Mar 2024 10:39:41 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73647 Wed 26 Jun 2024 11:52:05 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77254 Wed 05 Feb 2025 15:27:44 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77253 Wed 05 Feb 2025 14:18:01 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77252 0.995) suggesting that chemisorption governed the adsorption process. Similarly, the isotherm adsorption findings showed a good fit with the Freundlich model (R2 > 0.961). The findings indicated that the adsorption mechanism process was characterised by monolayer adsorption onto a heterogeneous adsorbent surface. Furthermore, the GO@Algae (1:3) was found to have the maximum adsorption capacity of 10.85 mg/g surpassing the capacities of both unmodified and NGO@Algae counterparts. The application of GO@Algae and NGO@Algae has the potential to promote the green reuse of graphene-based nanomaterials. In summary, GO@Algae and NGO@Algae show great potential as eco-friendly adsorbents for the feasible treatment of heavy metal-contaminated water.]]> Wed 05 Feb 2025 13:28:45 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77251 Wed 05 Feb 2025 11:57:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77250 Wed 05 Feb 2025 11:22:44 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72811 Tue 28 May 2024 15:52:21 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72935 Tue 04 Jun 2024 09:17:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72934 Tue 04 Jun 2024 08:40:58 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77227 91% DMA), while the experiment with all three anilines present also resulted in a complex with an]]> Tue 04 Feb 2025 11:35:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77225 Tue 04 Feb 2025 11:15:02 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73735 Tue 02 Jul 2024 09:02:10 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72821 Thu 30 May 2024 15:19:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73660 Thu 27 Jun 2024 15:06:01 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73658 Thu 27 Jun 2024 14:51:41 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73657 Thu 27 Jun 2024 14:30:42 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73656 Thu 27 Jun 2024 13:28:10 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73655 Thu 27 Jun 2024 13:06:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73654 Thu 27 Jun 2024 12:46:18 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73653 Thu 27 Jun 2024 12:17:45 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73651 Thu 27 Jun 2024 11:49:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72754 Thu 23 May 2024 12:33:21 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72736 Thu 23 May 2024 10:26:18 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72728 Thu 23 May 2024 10:00:39 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72675 Thu 23 May 2024 08:54:53 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73566 Thu 20 Jun 2024 16:01:55 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73562 7-ONE > 8-ONE > 5-ONE which correlated exactly with results from binary guest/guest competition experiments, where 6-ONE was always preferred by H1, while 5-ONE was consistently disfavoured. Single crystal X-ray diffraction (SCXRD) analyses demonstrated that each guest compound was retained in the crystals by means of a hydrogen bond with an alcohol moiety of the host compound. Furthermore, preferred guests 6- and 7-ONE produced crystals with greater densities than guests less favoured (5- and 8-ONE). A conformational analysis of the guest geometries in the four complexes with H1 revealed that the low energy guest conformers were present. The host selectivity for 6- and 7-ONE was proposed to be due to the improved molecular packing in the crystals of the complexes containing these two guest compounds, observed from their higher crystal densities. Hirshfeld surface analyses were not useful in explaining the preference of H1 for 6-ONE relative to 7-ONE (these types of analyses were not possible for the 5-ONE and 8-ONE-containing inclusion compounds due to the nature and degree of disorder present in the guest molecules). H1 was also crystallized from γ-butyrolactone (GBL), 2-pyrrolidone (NP), N-methyl-2-pyrrolidone (NMP) and N-ethyl-2-pyrrolidone (NEP), and 1H-NMR spectroscopy revealed that all but GBL were included. The host compound was also presented with these guest solvents in various mixtures, and it was observed that NMP was an extremely favoured guest solvent, followed by NEP and NP, with GBL being consistently disfavoured in every experiment. It was therefore shown that in certain instances, H1 may serve as an alternative tool for separating some of these mixtures through host-guest chemistry strategies. The hydrogen bonding motifs present in each of the successfully formed complexes were extensively investigated through SCXRD analysis, as was the thermal behaviour of these complexes. In the latter instance, the peak temperature of the endotherm (from the DSC trace) representing the guest release was greater for the inclusion compound with favoured NMP (145.5 °C) relative to the complexes with NP (139.8 °C) and NEP (120.5 °C). Host compounds H2 and H3 were revealed to have the ability to include each of pyridine (PYR), 2-methylpyridine (2MP), 3-methylpyridine (3MP) and 4-methylpyridine (4MP). H2 displayed selective behaviour for 3MP and 4MP when presented with mixtures of these guest compounds, whilst H3 preferred PYR. In the latter case, this PYR-containing inclusion compound was also the more stable one (the guest release onset temperature was highest, Ton 66.0 °C). It was demonstrated that H2 has the ability to separate very many binary mixtures of these pyridines on a practical platform, since K (the selectivity coefficient) values were 10 or greater in many instances. However, unfortunately, the more difficult-to-separate mixtures containing 3MP and 4MP cannot be purified or separated by employing H2 and supramolecular chemistry strategies. H3 was also shown to be a likely candidate for binary guest separations in very many of the guest solutions considered here, where K was also 10 or greater, and even infinity in many cases. SCXRD demonstrated that 2MP, 3MP and 4MP were retained in the crystals of their complexes by means of classical hydrogen bonds with the host compound. Satisfyingly, this hydrogen bond between 2MP and H2 (3.0213(18) Å) was significantly longer than that between this host compound and both disorder components of 3MP (2.875(2) and 2.825(9) Å) and that between H2 and 4MP (2.8458(13) Å). This observation explains the affinity of H2 for both 3MP and 4MP, and why 2MP was disfavoured. The results of thermal experiments did not wholly concur with observations from the guest/guest competition experiments. Hirshfeld surface analyses were also conducted but were not entirely conclusive with respect to explaining the host selectivity behaviour. In the case of H3, SCXRD analyses revealed that favoured PYR experienced a classical hydrogen bond with the host compound that was statistically significantly shorter (2.795(2) Å, 165°) than those between the other guest compounds and H3. Additionally, this guest compound was the only one to be involved in a (host)C−H···π(guest) interaction (2.91 Å, 139°) and also a non-classical hydrogen bond with the host compound ((host)C−H···N−C(guest), 2.77 Å (144°)). Finally, Hirshfeld surface analyses showed also that preferred PYR experienced a greater percentage of C···H/H···C (33.1%) and H···N/N···H (11.1%) interactions compared with the complexes with 2MP, 3MP and 4MP. However, it is not clear whether these Hirshfeld observations explain the affinity of H3 for PYR.]]> Thu 20 Jun 2024 15:42:01 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73554 Thu 20 Jun 2024 14:46:36 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77264 Thu 06 Feb 2025 14:17:35 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77263 Thu 06 Feb 2025 13:49:52 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77260 0.05) for any of the tested soil nutrient availability and soil acidity parameters, except for pHw. However, lime rate effects were significant (p<0.05) on AS, EA, pH(KCl) and ext Al. As lime rate increased, the acidity decreased. Increasing the lime application rate significantly (p<0.05) enhanced the cation exchange capacity (CEC), calcium (Ca), magnesium (Mg) and phosphorous (P), but decreased potassium (K) and sulphur (S). The availability of micro-nutrients namely copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) also decreased as the lime rate increased. Biochar effects on EA, AS, pH(KCl) and ext Al were not significant (p>0.05). However, the biochar significantly reduced the availability of Ca and Mn but did not have a significant effecton all the other nutrients at the tested application rates. Unenriched biochar at 10 t ha-1 had an acidifying effect on the soil as it increased EA, when compared to enriched biochar. The significant (p <0.05) biochar × lime × time interaction effect on pHw showed that biochar applied without lime increased pHw, and the benefits were greatest at 10 t ha-1 biochar application rate. Similarly, lime applied without biochar also had a significant positive effect on pHw and the benefit increased at higher lime application rates. After 60 days of incubation, the lime applied at the highest rate of 5 t ha-1 without biochar (0 t ha-1 biochar) had the highest final pHw value. The 3-way interaction of lime, biochar and genotype was not significant (p>0.05). Koonap, the acid tolerant wheat variety outperformed the sensitive variety, Gariep under all treatments in the acid soil, as expected. There was, however, a significant (p<0.05) lime rate × biochar interaction. The highest application rates of lime (5 t ha-1) and biochar (10 t ha-1) were the best combination for root length for both the varieties. Overall, these results suggested a possible buffering effect of biochar at low lime application rates, thus limited benefits of combining reduced lime doses with biochar on reducing soil acidity or enhancing nutrient availability. The null hypothesis was thus rejected, and it was concluded that co-application of reduced lime rates and biochar will not significantly enhance benefits of liming. However, a positive interaction from co-application of biochar and lime on both pH and plant growth is possible at high application rates of both biochar and lime.]]> Thu 06 Feb 2025 13:00:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77259 Thu 06 Feb 2025 11:43:37 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77256 3MP > 4MP > 2MP. The behaviour of TADDOL5 was further investigated in guest compounds DIO, PYR, PIP and MOR. Each guest solvent formed 1:1 H:G inclusion complexes with the host species, with the exception of DIO, which formed a 2:1 H:G complex. Mixed guest experiments revealed a clear preference for PIP and MOR, while PYR and DIO were less favoured. The host selectivity was demonstrated to be in the order PIP > MOR > PYR > DIO. SCXRD experiments showed that TADDOL5 formed a much shorter (and more linear) (host)O‒H···N(guest) hydrogen bond with the most favoured guest, PIP, compared to those involving MOR and PYR. A (host)O‒H···O(guest) hydrogen bond was also observed in the DIO-containing inclusion complex. A consideration of the Hirshfeld surface interactions was not useful in explaining the host selectivity order for these heterocyclic guests, but thermal analyses confirmed that the most stable complex was the one with favoured PIP, followed by those with PYR, MOR and DIO. TADDOL6, on the other hand, formed 1:1 H:G inclusion compounds with all four of the heterocyclic guest solvents. Experiments in mixed guests showed that the selectivity of this host compound for these guests was in the order PYR > PIP > MOR > DIO, which differed from the TADDOL5 (which favoured PIP and then MOR). Interestingly, the strongest classical hydrogen bond was not formed with the most favoured guest PYR, but with PIP instead (this bond with TADDOL5 was also strongest with PIP, but PIP was favoured in that work). Hirshfeld surface investigations again were not useful in understanding the host selectivity behaviour. However, thermal analyses agreed with the observations made in the mixed guest experiments: the most stable complex was with PYR (favoured) and the least stable one was with DIO (least preferred).]]> Thu 06 Feb 2025 09:09:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72779 Mon 27 May 2024 13:13:53 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72778 hawksbills > loggerheads > leatherbacks). However, sightings per unit effort (SPUE) showed that loggerheads were more prevalent than hawksbills in iSimangaliso, likely due to its proximity to this loggerhead rookery. Reefs supported mixed size aggregations with juvenile to adult-sized green turtles (straight carapace lengths, SCLs of 44.9–99.2 cm), whilst hawksbills were mostly juveniles or subadults (SCL range: 37.4–73.4 cm) and loggerheads were mostly adult-sized (SCL range: 66.9–81 cm). Adult sex ratios were slightly female-biased but not significantly different from 1:1. The longest minimum residence periods recorded for individual subadult green and hawksbill turtles (676 and 675 days respectively) and adult-sized loggerheads (621 days) were suggestive of residency. Resident sea turtle activities were typical; they wereobserved foraging, resting, cleaning and interacting year-round, whilst only loggerheads and leatherbacks were observed in breeding behaviour (e.g., patrolling and mating) just after the seasonal arrival of transient individuals. This study thus reveals that the east coast of South Africa hosts regionally important resident and transient sea turtle aggregations with some of the highest SPUE results recorded for the region. This first attempt at monitoring foraging grounds using a variety of techniques and stakeholder groups can serve as the baseline assessment for future work and the foundation for a long-term in-water monitoring programme, allowing for expansion along the entire coastline.]]> Mon 27 May 2024 12:24:52 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73614 Mon 24 Jun 2024 15:41:42 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73613 Mon 24 Jun 2024 14:52:00 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77276 Mon 10 Feb 2025 14:17:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72933 Mon 03 Jun 2024 15:51:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72932 Mon 03 Jun 2024 15:36:53 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72931 200 m depth) are challenging to access and remain poorly studied globally. Epifaunal invertebrates comprise a critical trophic level in benthic ecosystems and can serve as indicators of the overall health and functioning. There is limited knowledge of South Africa’s offshore marine environment and benthic ecosystem functioning due to limitations in funding, resources, and the lack of suitable science-based monitoring tools which are vital for sustainable management into the future. The aim of this research was to improve the understanding of epifaunal functioning as well as their potential physical drivers in 13 South African offshore biogeographic ecotypes. The objectives of this study were threefold: 1) to investigate the functional composition of benthic epifauna from 13 biogeographic ecotypes, 2) to quantify the Functional Diversity (FD) associated with epifaunal traits between the different assemblages (i.e. biogeographic ecotypes), and 3) to evaluate the relationship between physical variables and epifaunal functional traits at the biogeographic ecotype level. Biological trait-based approaches were applied to a subset of 80 benthic epifaunal species collected from 909 offshore stations along the west and south coasts of South Africa. Nine biological traits (associated with life history, morphology and behavioural characteristics exhibited by each species) were classified into 39 modalities and weighted with biomass. Community Weighted Means (CWMs) were used to evaluate the benthic epifaunal functional trait composition of the 13 biogeographic ecotypes. Functional composition across the 13 ecotype assemblages on the west and south coast appeared to be dominated by species with similar trait compositions, such as large, long-lived, surface crawling/burrowing/filter-feeding epifauna with medium to no mobility, however, their percentage of contribution to trait expression (CWMs) was higher on the west coast. Functional diversity indices (alpha and beta) showed higher overall FD for west coast ecotypes, with most ecotypes on the continental shelf (except slopes and canyons) being significantly different (p<0.05) from ecotypes on the south coast. The global RLQ (three-table co-inertia) test did not reveal a significant relationship between biomass and physical variables or between biomass and traits (p>0.05). The fourth-corner method was used to test the significance of individual traitenvironment relationships. The fourth-corner results were similar overall to the RLQ analysis, revealing that three physical variables (temperature, depth, and fluorescence) were significantly correlated to two trait modalities belonging to the feeding mode filter-feeders (FM1) and scavengers (FM5). Scavengers were positively correlated with depth and negatively with temperature, while filter-feeders were positively correlated with fluorescence levels. This indicated that the presence of scavenging epifauna increased with a decrease in temperature and an increase in depth. While a positive significant correlation between filter-feeders and fluorescence suggested their potential tolerance or preference for environmental conditions with high levels of fluorescence. This research was the first such study to explore the functional composition and diversity of benthic epifauna and their relationship with potential physical drivers in offshore west and south coast benthic biogeographic ecotypes of South Africa. The application of new tools to quantify the functional diversity of epifauna as indicators of ecosystem health, and their potential physical drivers. This provided a platform on which to advance our understanding of benthic communities and the roles they play in ecosystem functioning under changing environments. Functional trait-based approaches such as those applied in this study can provide us with vital information on the relationship between biodiversity, ecosystem functioning, and physical drivers. Environmental stressors and changing climate patterns threaten to impact marine ecosystems and their functioning. Benthic epifauna are especially sensitive to changes in their environment and these fluctuations could potentially lead to the loss of certain benthic functionality, altering the thresholds these ecosystems have to response to disturbances. This undermines the stability of these ecosystems which can have ripple effects on the health of these ecosystems and their ability to provide the ecosystem services humans dependent on. Having suitable tools to track current and predict future changes will therefore be vital to inform management and conservation strategies for sustainable ocean utilisation.]]> Mon 03 Jun 2024 15:17:03 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72925 Mon 03 Jun 2024 14:40:41 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72912 Mon 03 Jun 2024 13:47:30 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72907 Mon 03 Jun 2024 12:33:03 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72887 Mon 03 Jun 2024 12:06:31 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72906 Mon 03 Jun 2024 11:17:32 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72899 100 years) and harbours forest species, many of which were vertical growers. The second unit, thicket, is exposed to moderate levels of fire frequency (50-100 years) and is dominated by lateral spreaders. The last unit, fynbos-thicket, is exposed to high levels of fire frequency (10-50 years) and here hedge-forming shrubs dominate the canopy cover. Forest-thicket and fynbos-thicket had a diverse set of shrub species with many being restricted to their respective vegetation type, whereas thicket had a lower diversity with no unique shrub species.]]> Mon 03 Jun 2024 09:44:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77216 Mon 03 Feb 2025 15:07:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77205 Mon 03 Feb 2025 11:30:10 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73713 Mon 01 Jul 2024 12:25:56 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73710 Mon 01 Jul 2024 12:04:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73704 Mon 01 Jul 2024 11:50:51 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73695 Mon 01 Jul 2024 11:40:14 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73692 Mon 01 Jul 2024 10:32:59 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73689 Mon 01 Jul 2024 10:16:44 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73684 Mon 01 Jul 2024 09:58:01 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72828 Fri 31 May 2024 14:09:47 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72827 Fri 31 May 2024 13:48:47 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72826 Fri 31 May 2024 13:20:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72825 Fri 31 May 2024 12:52:54 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72824 Fri 31 May 2024 10:41:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72823 Fri 31 May 2024 10:32:54 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:72822 Fri 31 May 2024 10:11:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77164 Fri 31 Jan 2025 14:59:09 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77161 Fri 31 Jan 2025 14:03:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77160 Fri 31 Jan 2025 13:42:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77159 Fri 31 Jan 2025 13:35:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77153 Fri 31 Jan 2025 13:07:28 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77135 90%) is important in terms of optimising rotation-end yield. The industry origin of a 90% survival benchmark is unclear, although company procedures incorporate this as the minimum threshold in terms of re-establishment success. Past research indicates that most mortality occurs within a narrow period post-establishment and is often associated with substandard re-establishment practices and/or a stressed micro-environment. An improved understanding is needed about the various mitigation measures needed to minimize mortality during eucalypt re-establishment. Before making decisions related to mortality mitigation measures, comprehensive data are required as to their commercial applicability as well as outcomes from multiple trials that accurately quantify any impacts on tree survival and financial return. The overall purpose of this dissertation was the optimisation of Eucalyptus re-establishment practices for improved survival, growth and uniformity in South African pulpwood plantations. To achieve this, five inter-linked objectives were determined. The first objective was to highlight the most important factors contributing to increased mortality in eucalypt plantations during re-establishment. This was achieved through conducting a literature review. Citations were ranked in terms of credibility, with the importance ratings (derived from the literature sources) applied to the different factors affecting survival and growth during eucalypt re-establishment. Of the various factors impacting early eucalypt mortality, water stress and planting stock quality were considered highly important. The manner and quality of site preparation (soil and slash), planting practices (planting depth included), timing of planting (during dry, hot periods), various post-planting operations (incorrect fertiliser placement or herbicide drift) and insect pests and diseases also contribute to mortality, but to a lesser extent. These factors cannot be considered in isolation due to the complex interactions that exist between them and determining the primary causes of mortality can be elusive, especially as their impacts tend to be additive by nature. The second objective was to link survival to silvicultural treatments, site-related physiographic factors and climatic variables in South Africa. This was achieved by conducting an integrated analysis of 43 Eucalyptus trials. Of the seven re-establishment practices considered, watering, planting depth and fertiliser application were significant, with plant size, pitting method, residue management and insecticide application were not significant. However, when environmental variables were included within the analyses, there were significant site x treatment interactions for planting depth, plant size, residue management and fertiliser application. This highlights the importance of taking site related factors into consideration when interpreting the causes of mortality. The third objective was to determine the interaction between planting density and mortality on Eucalyptus growth, uniformity and financial yield at rotation end in South Africa. This was carried out to verify whether planting at different densities may be used as a preventative (before planting) mitigation measure. One trial was used to answer four keys sub-objectives: 1) The impact of three planting densities (1 102, 1 500, 1 959 SPH) with no mortality on yield at rotation-end; 2) The impact of mortality (0%, 10%, 20%, 30%, 40%) on rotation-end yield; 3) The quantification of tree performance when planting at a higher density and accepting a certain degree of mortality; and 4) The financial impact of different planting densities and mortality on rotation-end profit. Higher planting densities resulted in smaller individual trees, but with an increase in stand level performance. At rotation-end, lower mortality (0% and 10%) had significantly higher volumes ha-1 than the higher mortality (30% and 40%). Planting at higher densities (1 722 and 1 959 SPH) and accepting a certain degree of mortality resulted in non-significant differences for volume at rotation-end compared to the fully stocked 1 500 SPH treatment. A higher SPH resulted in a higher yield, but with an increase in estimated establishment/tending and harvesting costs. In contrast, an increase in mortality and/or lower SPH (in the absence of mortality) resulted in more variable stand growth, together with an increase in estimated machine harvesting productivity and reduced costs. Irrespective of SPH, the higher the mortality the greater the loss of income, with the best profit within each treatment related to full stocking (0% mortality). Within the higher panting densities, the profit gained following low mortality (10 and 20%) was similar to that of no mortality (0%), indicating that higher mortality may be tolerated when planting at higher densities, confirming the 90% survival threshold the industry aims to achieve post-establishment. The fourth objective was to determine if silviculture intervention (blanking at 1, 2 and 3 months or coppicing and interplanting at 6 months) will result in acceptable eucalypt stocking, if mortality is higher than 10% (remedial mitigation measure). Data from a re-establishment trial were analysed to determine which of the mitigation measures performed best in terms of stocking and growth. Coppicing and interplanting with larger plants was not a viable option as a mitigation measure for mortality as most of the coppice shoots have died. This may have been a result of frost. Although high re-establishment costs may be incurred, disaster clearing to waste followed by replanting is an option if mortality is unacceptably high (as opposed to leaving the stand as is). The results of this objective confirm that blanking as the current Best Operating Practice is still appropriate in South African forestry (i.e., try to have survival >90% and blank as soon as possible to retain >90% of stems). Blanked plants do contribute to volume, but for this to occur, blanking should be carried out within 4 weeks after planting to gain maximum benefit. In addition, it highlights the importance of implementing remedial mitigation measures to achieve >90% survival so as to gain maximum benefit. Using the outcomes from objectives 1-4, the fifth objective focussed on the development of a decision support system (DSS) for implementation of mitigation measures to improve survival within commercial eucalypt pulpwood plantations in South Africa. Improved survival starts with the implementation of good re-establishment practices and good quality planting stock. Mitigation measures for poor survival can be implemented either prior to re-establishment (before mortality occurs) or post re-establishment (after mortality has occurred). If poor survival still occurs after the implementation of good silviculture practices and pre-re-establishment mitigation practices (planting at higher densities), one should consider the various options available in terms of post re-establishment mitigation practices (remedial practices) such as blanking or replanting if mortality is high. Overall, the outcomes from this dissertation provide benchmark data and derived information as to the necessity for various mortality mitigation options within the commercial forestry sector in South Africa. In addition, the DSS will assist with decision making in terms of implementing the best silviculture practices and mitigation measures for improved survival during eucalypt re-establishment in South African pulpwood plantations.]]> Fri 31 Jan 2025 12:04:12 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77127 Fri 31 Jan 2025 11:43:38 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77122 Fri 31 Jan 2025 11:07:58 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77121 Fri 31 Jan 2025 10:25:54 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:77120 Fri 31 Jan 2025 09:50:54 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73677 mangrove bee honey > U. fasciata > S. oligocystum > 2-PAA > green rooibos. Unexpected results were demonstrated for green rooibos in the presence and absence of red light, which included decreased ATP production and collagen biosynthesis. Further investigation is therefore needed to have a better understanding of these unanticipated results.]]> Fri 28 Jun 2024 15:29:32 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73668 Fri 28 Jun 2024 14:52:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73676 Fri 28 Jun 2024 14:39:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73675 Fri 28 Jun 2024 14:25:06 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73674 Fri 28 Jun 2024 14:11:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73672 Fri 28 Jun 2024 13:49:34 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73671 Fri 28 Jun 2024 13:35:15 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73670 Fri 28 Jun 2024 12:46:39 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73669 Fri 28 Jun 2024 12:19:02 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73666 Fri 28 Jun 2024 11:30:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73665 Fri 28 Jun 2024 11:02:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73664 Fri 28 Jun 2024 10:20:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73663 Fri 28 Jun 2024 10:05:59 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73659 Fri 28 Jun 2024 08:05:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73597 Fri 21 Jun 2024 15:41:26 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73596 Fri 21 Jun 2024 14:52:56 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73595 Fri 21 Jun 2024 14:31:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73594 Fri 21 Jun 2024 14:09:53 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73593 Fri 21 Jun 2024 13:49:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73592 Fri 21 Jun 2024 13:14:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73590 Fri 21 Jun 2024 12:18:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73589 Fri 21 Jun 2024 12:03:47 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73578 Fri 21 Jun 2024 10:26:35 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73576 Fri 21 Jun 2024 10:05:31 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:73571 Fri 21 Jun 2024 08:33:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:36669 Fri 15 Mar 2024 13:06:48 SAST ]]>