University of Port Elizabeth

About: University of Port Elizabeth is a based out in . It is known for research contribution in the topics: Population & Estuary. The organization has 1067 authors who have published 1538 publications receiving 38560 citations. The organization is also known as: UPE & Universiteit van Port Elizabeth.

The role of estuarine type in characterizing early stage fish assemblages in warm temperate estuaries, South Africa

Abstract: Assemblages of early stage fishes (larval and early juvenile stages) were investigated and compared in seven permanently open and five intermittently open estuarine systems on the warm temperate Eastern Cape coast of South Africa. Estuarine type, by virtue of mouth state and prevailing physico chemical conditions, played a defining role in the structure of these fish assemblages. Clupeidae and Gobiidae were the dominant fish families in both estuarine types. Permanently open estuaries were characterized by the predominance of larvae and early juveniles of estuary dependent marine fish species while estuary resident fishes dominated intermittently open estuaries. Seasonal changes were observed in species density and diversity in both estuarine types. Species richness and diversity were highest in the permanently open Swartkops Estuary that is characterized by large nursery habitat availability. Species diversity was high in estuaries with a good supply of freshwater, that results in good recruitment of est...

Gay and Lesbian Youth Experiences of Homophobia in South African Secondary Education

Abstract: In post-apartheid South Africa, the tenets of inclusivity, nondiscrimination, and tolerance are actively encouraged and legislated across all sectors of society, including education. However, in examining the coming out experiences of 18 South African gay and lesbian youth (1997-2000), it became apparent that they had all experienced discrimination, isolation, and nontolerance within their high school contexts. Due to the marginalized nature of the participants, a variety of nonpurposive sampling techniques were utilized. This article provides insights into the homophobic incidents and experiences as articulated by these sexual minority youths, namely, peer harassment, harassment inflicted by teachers and school administrators, ineffective school counsellors, avoidance, rejection and isolation, and a lack of information and curriculum in high schools for gay and lesbian youth. Implications for practice are considered in the context of South Africa's new constitution and the implementation of Curr...

A re‐assessment and refinement of RECOVSAT: An instrument to measure satisfaction with transaction‐specific service recovery

Abstract: Purpose – To do an empirical assessment of the psychometric properties of an instrument that captures the multi‐dimensional nature of satisfaction with service recovery (RECOVSAT) using data (post‐recovery satisfaction ratings) from customers who have actually complained to a service firm.Design/methodology/approach – The methodology is a survey of bank clients who have lodged complaints with a retail bank.Findings – The empirical results suggest that a refined and shorter version of RECOVSAT demonstrates excellent construct validity when used to measure the post‐recovery satisfaction of complaining customers.Research limitations/implications – RECOVSAT is a valid and reliable instrument that can and should be used by service managers to assess customer satisfaction with their service recovery efforts. Failure to ensure that complaining customers are satisfied with the firm's service recovery efforts, can only lead to serious problems, as the service firm will be letting the customer down for the second t...

Community structure on sandy beaches: patterns of richness and zonation in relation to tide range and latitude

Abstract: Recent studies have shown a consistent increase in species richness, abundance and biomass of intertidal macrobenthos over a range of micrornesotidal sandy beaches from reflective to dissipative conditions. However. beaches occur in a continuum of morphodynamic forms beyond mesotidal dissipative in rnacrotidal areas: these are ultradissipative beaches and tide flats, where tides take over from waves as the controlling force. This paper tests the hypotheses: I) that species richness. abundance and biomass continue increasing and 2) that more than three fauna! zones may be distinguished on beaches on the above continuum beyond the mesotidal dissipative type. and also examines the hypothesis: 3) that temperate beaches are richer in species than tropical beaches. Two temperate. microtidal. dissipative beaches and four tropical, macrotidal. ultradissipative to tidal tlat beaches in Australia were quantitatively surveyed with a total sampling area of 4.5 m 2 each. The results, when plotted against an index of beach state. indicate that species richness continued to increase over this range of beach types and especially strongly towards the tidal flat. Abundance also increased. but only weakly towards the tidal flat and biomass showed a decreasing trend. The tropical beaches (15-30 species) supported richer faunas than the temperate (12 species) beaches. Similar response to an index of beach state by communities from widely differing regions and latitudes suggests that species richness is probably mainly a function of beach type and latitude may play a minor role. Zonation was indistinct in most cases and no more than three zones could be distinguished on any of the beaches. It appears that in macrotidal regimes, where tides take over from waves as the force controlling beaches. intertidal climate becomes more benign, leading to the presence of species that construct semi-permanent burrows. the attainment of high diversity and thus the development of suitable conditions for biological interactions to play a greater role in community organisation than on microtidal, wave-dominated beaches.

Effect of River Flow on Estuarine Microalgal Biomass and Distribution

Abstract: Impoundments and abstraction from rivers have reduced the amount of riverwater flowing into estuaries. This has necessitated research on the riverwater requirements of these important ecosystems. A study was initiated on the structure and biomass of microalgae in the Gamtoos estuary (Eastern Cape Province, South Africa) in order to improve our capability to predict changes and determine the acceptability of reduced riverwater input. The mean annual runoff of the Gamtoos River has been halved by major impoundments. Agriculture in the Gamtoos estuary valley contributes high concentrations of nutrients through groundwater seepage and an extensive sub-surface drainage system. This study determined the responses of microalgae to the volume of river discharge. A strong longitudinal salinity gradient was present at water flow rates ranging from 0·3 to 30·5 m 3 s −1 . There was strong vertical stratification at flows above 1 m 3 s −1 . Nitrate concentration increased from 1·9±0·2 μM (at 0·3 m 3 s −1 ) to 83·6±13·8 μM (at 30·5 m 3 s −1 ). Phytoplankton biomass was highest in the oligo- and mesohaline reaches of the estuary and was strongly correlated to turbidity. Phytoplankton chlorophyll a was highest at flow rates of 0·8 (47·5±4·5 μg l −1 ) and 1·16 m 3 s −1 (49·9±7·3 μg l −1 ). Subtidal and intertidal benthic chlorophyll a were highest at flow rates of 1·0 (57·7±0·4 kg) and 1·16 m 3 s −1 (8·7±0·1 kg) respectively. A riverwater input rate of ∼1·0 m 3 s −1 appears optimal for phytoplankton and benthic microalgal growth. At this flow rate, the estuary acts effectively at removing excess nutrients from the water before it discharges to the sea.