This research analyzed the disinvestment in higher education in Illinois. This study is an exploratory case study based on interviews with eleven Presidents, Vice Presidents, and Associate Vice ...Presidents of Enrollment Management from nine Illinois public universities, qualitative analysis, and secondary data. This study revealed four main themes: the challenges in public universities due to disinvestment in higher education, students migrating outside Illinois, the importance of AIM HIGH Grants, and increased creativity in recruiting students by admissions departments. Disinvestment in higher education had the following impacts: increased tuition, diminished enrollment of students, students migrating outside Illinois, deferred maintenance, loss of talented faculty, and reduction of capital projects.
Microplastics are small plastic materials often defined as those between 5 mm and 0.05 mm in size. Microplastics can have toxicological impacts on various biota, from gut blockages to the transport ...or leaching of toxicants used in their production or absorbed from the surrounding environment. Although microplastic research has increased significantly, microplastic research in Africa lags behind that of developed countries. South Africa is the African nation with the highest number of microplastic publications. We aimed to determine the current state of microplastic research in South Africa. A total of 46 publications on microplastics in South Africa have been produced. However, many of these publications use methods that might not be accurate in determining holistic descriptions of microplastics in the aquatic environment. Similarly, many ecologically relevant environments and species have not been investigated for microplastics in the country, including any atmospheric or terrestrial environment. We conclude that, although the research being produced in South Africa can be considered adequate, a singular standard method for sampling and assessing microplastics in South African environments is required. The production of such a standard method would be critical to use as a monitoring tool to determine and compare microplastic abundances across the country and globally.
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•Makuleke Wetlands receive water from rivers influenced by anthropogenic inputs.•Multivariate macroinvertebrate analyses to assess ecosystem structure and function.•Aquatic ...biodiversity was some of the highest recorded in the Global South.•Wetland ecosystem structure is in a suitable condition to support high biodiversity.•Invasive species threaten native biodiversity in this premier conservation area.
The Ramsar-accredited Makuleke Wetlands are located in the Makuleke Concession in the northern Pafuri region of the Kruger National Park in South Africa. The Pafuri area holds up to 75% of Kruger National Park’s total biodiversity, emphasising the Makuleke Wetlands’ international environmental importance. The Makuleke Wetlands are composed of the floodplains of the Luvuvhu and Limpopo rivers, with an estimated 31 wetlands present within the floodplains. Ten floodplain wetlands were assessed in the Makuleke region, eight of which are fed by the Limpopo River and the other two from the Luvuvhu River. Water and aquatic invertebrate communities were sampled at each site during surveys in April and September 2015 to provide baseline information on the aquatic biota of this Ramsar site. Multivariate data analytical techniques were used to assess the role of season and water quality in structuring the aquatic invertebrate communities of the wetlands. Macroinvertebrate functional feeding group ratios were also calculated as an indication of wetland ecosystem structure and function. Aquatic invertebrate diversity was some of the highest recorded for wetlands in South Africa, indicating the important role these habitats play in supporting high biodiversity in the Makuleke region. Worryingly, one of the most prolific invasive molluscan species, Tarebia granifera, was present in the wetlands and is a significant threat to native biodiversity of this conservation area. Community characteristics and ecosystem structure and function of the aquatic invertebrates further indicated that the Makuleke Wetland habitats were of good quality and provided a sufficient stable substrate for all aquatic invertebrates. Functionally, the system was characterised as reliant on heterotrophic inputs as autotrophic sources are limited. This is the first study of its kind for the region and lays the groundwork for future ecosystem studies on these important wetlands in the second-largest floodplain of South Africa.
Microplastics are defined as plastics smaller than 5 mm down to 0.05 mm. These plastics enter the environment and undergo certain physical changes, most notably density changes and a relative ...increase of surface size. Microplastics can then release or absorb toxicants from the surrounding environment. These plastics may then enter the food chain from producers to top predators. In this study, microplastics were investigated in four study sites in the upper Vaal River, South Africa. The goal of the study was to determine the levels of plastics in water, sediment and a top predator, the benthic fish
Clarias gariepinus
. In this study, a 10% KOH digestion of water and fish, and density separation of sediment with NaCl (1.2 g cm
3
) was used to extract microplastics for identification. Microplastics were detected in water (3, 300 particles m
−
³), fish (7.47 particles per fish) and sediment (46.7 particles kg
−1
). Microplastic intake was not attributed to the microplastic shape or size of the fish that ingested it. This highlights the need to understand how niche-specific microplastic concentrations are, which will not only aid in quantifying microplastics accurately in the environment but to better understand how they may influence various ecosystems.
Nineteen species of abundant gastropods were collected at Robben Island, including introduced dune snails and European brown garden snails. They were identified using morphology and DNA barcoding. It ...was expected that the species recorded would be similar to those from the Cape peninsula, South Africa, but we were surprised to find some exceptions: the very abundant invasive mussel species in South Africa, the South American bisexual mussel (Semimytilusalgosus), and the beaded topshells (Oxysteleimpervia) were not found on Robben Island. Possible explanations are presented for these differences.
The genus Oxystele, a member of the highly diverse marine gastropod superfamily Trochoidea, is endemic to southern Africa. Members of the genus include some of the most abundant molluscs on southern ...African shores and are important components of littoral biodiversity in rocky intertidal habitats. Species delimitation within the genus is still controversial, especially regarding the complex O. impervia / O. variegata. Here, we assessed species boundaries within the genus using DNA barcoding and phylogenetic tree reconstruction. We analysed 56 specimens using the mitochondrial gene COI. Our analysis delimits five molecular operational taxonomic units (MOTUs), and distinguishes O. impervia from O. variegata. However, we reveal important discrepancies between MOTUs and morphology-based species identification and discuss alternative hypotheses that can account for this. Finally, we indicate the need for future study that includes additional genes, and the combination of both morphology and genetic techniques (e.g. AFLP or microsatellites) to get deeper insight into species delimitation within the genus.
Microplastics are small plastic fragments that have been found around the world, however, research into microplastics in Africa and freshwater systems remains insufficient. In this study, the ...snapshot microplastic profile of an urban stream was assessed in the Braamfontein Spruit, located in Johannesburg the largest city in South Africa. The abundance of microplastics was determined in water, Chironomus sp. larvae and sediment, while in situ parameters were taken to investigate their relationship to the microplastic profile of the different matrices. Microplastics were detected in water (mean of 705 particles mˉ3), Chironomus sp. larvae (mean of 53.4 particles gˉ1 wet weight) and sediment (mean of 166.8 particles kgˉ1 dry weight). The study found evidence of how urban stream characteristics such as a weir, stream depth and velocity could affect the abundance and dispersion of microplastics. The results indicate that areas of increased depth and decreased flow allowed microplastics to settle down to the sediment where benthic macroinvertebrates could ingest these fragments. Large obstructions like a weir also increased microplastic counts in sediment and invertebrates above the obstruction, with a decrease of fragments after the obstruction, however, microplastics in surface water were able to flow over the obstruction and increase in abundance downstream. This study concludes that first order urban streams such as the Braamfontein Spruit may be contributing large numbers of microplastics to higher order streams and large rivers in times of increased flow.
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•Microplastics had a 100% prevalence in Chironomid larvae groups.•Stream characteristics could influence microplastic distribution.•Microplastic abundances varied depending on what matrix was being analysed.•A weir decreased microplastic loads downstream in sediment and invertebrates.
The toxicity of pesticides to non-target organisms continues to be important in understanding the dynamic interactions between anthropogenic chemicals and ecosystem health. This study assesses ...biochemical markers to determine the effects that varying concentrations of atrazine (13.1–5557 µg/l) have on the freshwater shrimp,
Caridina africana.
Exposure and oxidative stress biomarkers were analysed and followed by univariate, integrated biomarker response v2 (IBRv2) and Kendall Tau correlation statistical analyses, to gain insight into the concentration-dependent responses. Oxidative stress biomarkers such as reduced glutathione content (GSH), glutathione-S-transferase activity (GST), superoxide dismutase activity (SOD) and catalase activity (CAT) were significantly correlated with increasing atrazine exposure concentration (p < 0.01). Bimodality has been seen when looking at both the univariate statistically significant differences as well as the IBRv2, with the first peak at 106.8 µg/l and the second peak at 5557 µg/l atrazine. The results indicate that while individual responses may indicate statistically significant differences, using correlation and integrated statistical analysis can shed light on trends in the adaptive response of these.
Vanadium (V) is a transition metal that is found in low concentrations in aquatic ecosystems. These levels increase due to anthropogenic activities. The mortality and teratogenicity effects of V ...remain unexplored in amphibian species. To address this gap in the knowledge base, a standard Frog Embryo Teratogenic Index –
Xenopus
(FETAX) assessment was conducted. Vanadium pentoxide (V
2
O
5
) was chosen for its known toxicity in other aquatic biota and its solubility in water. A range-finding test was conducted in two different mediums, V
2
O
5
in distilled water (VDH2O) and V
2
O
5
in FETAX medium (VMED), to determine concentration ranges where effects occurred. Thereafter, definitive tests were conducted using two separate breeding pairs, with two replicate dishes per concentration containing 15 embryos each. Multiple endpoints were assessed including mortality, malformations, minimum concentration to inhibit growth (MCIG), and the teratogenic index (TI). Mortality and malformation effects occurred at different ranges, and therefore, the exposures were conducted in low dose and high dose ranges. The high dose range for mortality effects was conducted at 0, 10, 20, 40, 80, and 160 mg/L of V. The low dose exposures to assess malformation effects were conducted at 0.0001, 0.00025, 0.0005, 0.00075, and 0.001 mg/L. Binary logistic regression was used to determine the LC50 and EC50 for the two sets of definitive tests. The LC50s were determined to be 46.10 mg/L and 26.91 mg/L for VDH
2
O and 34.50 and 25.25 for VMED for the two breeding pairs respectively. The EC50 was calculated as 0.00053 mg/L and 0.00037 mg/L for VDH2O and 0.00036 mg/L and 0.00017 mg/L for VMED for the two definitive tests respectively. The TI was calculated as 86,981 and 72,729 for VDH2O and 95,833 and 148,526 for VMED. Ultimately, there were severe malformation effects in embryos exposed to low doses of V and V was determined to be a very strong teratogen.
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