Water Footprint of Table Grape Production Systems: A Review of South African and Global Studies

Being a water-scarce country, South Africa (SA) faces several water challenges, including drought andother effects of climate change. Therefore, there is a need to improve water-use efficiency (WUE) by accuratelyquantifying the water use and WUE of table grape vineyards. The objective of this review is to (i)provide an overview of water footprint (WF) studies conducted on table grape production systems in SAand globally; (ii) identify limitations in current WF assessments of table grape production systems; and(iii) establish a range of WF values for table grape production systems as an indicator of WUE and for usein decision-making regarding sustainable freshwater use. The review has demonstrated that only a limitednumber of detailed WF studies have been undertaken on table grapes in SA and globally. Region-specificlookup tables for quantifying blue, green and grey water use in table grape production systems are availablefor three table grape production regions of SA and could be used for future WF assessments. Mostglobal studies conducted on grape WF and WUE were desktop studies and did not include actual fieldrecords from production units, nor did they distinguish between different grape types (table, raisin andwine grapes). WF values must be interpreted in context, specifically regarding the water used versus yield,quality and income, as well as the region, climatic conditions, soil characteristics, irrigation and cultivationpractices. For future WF and WUE assessments, a more detailed breakdown of water use is recommended,both during the production process and postharvest

Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the tissues of the largemouth yellowfish, Labeobarbus kimberleyensis (Gilchrist and Thompson, 1913), from the Vaal Dam, South Africa, and associated consumption risks

This paper addresses the accumulation of trace elements in the water, sediment and tissues of Labeobarbus kimberleyensis from the Vaal Dam, South Africa. Fish were collected from the Vaal Dam during February to April 2011. Five organs, water and sediment were collected and trace element concentrations were measured with an ICP-MS. Target hazard quotients were calculated to assess the human health risk associated with consuming muscle tissue of this fish species. Trace element levels for Cu, Fe and Mn were higher in water and sediment compared to L. kimberleyensis. Sediment element levels were highest compared to water and fish. Clear trends in element accumulation by the different organs were observed. Liver and kidney accumulated the highest element concentrations, followed by the gills, muscle and spinal cord. Bioconcentration factors further supported the observation that trace element accumulation was lower in fish compared to sediment. The high sediment element levels indicate that there is a low bioavailability of elements for accumulation by biota in the Vaal Dam. Target hazard quotient determination indicated that risk associated with the consumption of muscle tissue fromL. kimberleyensis was low for most elements, except Cr and Se. Element levels in L. kimberleyensis, water and sediment have increased compared to previous studies on the Vaal Dam.Keywords: bioaccumulation; Labeobarbus kimberleyensis; risk assessment; target hazard quotient; trace element; Vaal Dam; water qualit

Uptake of selected metals in tissues and organs of Clarias gariepinus (sharptooth catfish) from the Vaal River System – Chromium, copper, iron, manganese and zinc

This paper discusses concentrations of 5 essential trace metals (chromium, copper, iron, manganese and zinc) in water, sediment and various fish (C. gariepinus) tissues. With the exception of high Zn concentrations in skin, the highest essential element metal concentrations were generally recorded in liver and gill arch tissues, followed by gill filaments and lastly skin and muscle. This general trend is in agreement with trends reported by other workers. Fe concentrations were found to be significantly higher at the Vaal Dam more often than at the Vaal Barrage. In comparison, Mn concentrations were higher at the Vaal River Barrage more often than at the Vaal Dam. No clear trends emerged with regard to differences between localities for the other metals, or between surveys/seasons for all essential trace metals examined. The likely reason for the lack of distinct trends is the amount of variability observed in tissue metal concentrations within localities and seasons in this study. Such variability is also reflected in current literature and accentuates the importance of both abiotic (e.g. physical water quality variables) and biotic (e.g. host physiological status, general biology and life history traits) factors influencing the concentrations and bioavailability of trace metals

Trace element accumulation and human health risk assessment of Labeo capensis (Smith, 1841) from the Vaal Dam reservoir, South Africa

This paper aimed to determine the trace element concentrations within water, sediment and tissues of the Orange River mudfish Labeo capensis (Smith, 1841) collected from the Vaal Dam reservoir, and to assess potential risks associated with the consumption of L. capensis muscle tissue. The study was undertaken in March 2013; 22 L. capensis were collected with the aid of gill nets. Water and sediment samples were collected on site, and additional water analysis data for the sampling period were  received from Rand Water Analytical Facility in Vereeniging. Analysis of water revealed trace elements were present at trace levels. The comparison of trace element concentrations between the water, sediment and fish tissues revealed that the sediment contains the highest concentrations, followed by fish tissues and water. This trend exists as a result of the underlying geology of the Vaal Dam, the physiological and biological  characteristics of L. capensis, and the physicochemical state of the water. The risk assessment performed on the muscle tissue revealed that As and Se had total hazard quotient (THQ) values greater than one, and that the levels of As and Se were above the safety threshold values for human consumption.Keywords: Vaal Dam, Labeo capensis, trace element accumulation, bioaccumulation, health risks, target health quotien

Histomorphology of the digestive tract of Chonopeltis australis (Crustacea: Branchiura)

The morphology and histology of the digestive tract of the branchiuran crustacean, Chonopeltis australis Box shall, 1976 are described from serial sections. The foregut is differentiated into a preoral cavity, containing the mandibles and tongue, an ascending oesophagus, with an H-shaped lumen invested with longitudinal, circular and dilator muscles, a horizontal oesophagus with a star-shaped lumen and lacking longitudinal and dilator muscles, and an oesophageal funnel consisting of inner and recurrent walls. The midgut is differentiated into anterior and posterior chambers, separated by an S-shaped muscular tube. The arborescent midgut glands open laterally into the anterior part of the anterior midgut. Columnar epithelial cells line the anterior midgut whereas tall, papilliform cells are present in the epithelium of the posterior midgut. The transition from posterior midgut to hindgut is marked by the presence of very tall epithelial cells. The terminology describing the various parts of the digestive tract of branchiurans is discussed

Identifying flies used for maggot debridement therapy

To the Editor: The use of maggots to clean necrotic wounds, known as maggot debridement therapy (MDT), has long been known to the scientific world. Its use has been recorded since the 1500s when soldiers’ wounds were often infested with maggots. Napoleon’s surgeon, Baron Dominic Larrey, reported that wounds that were infested with maggots appeared to heal faster than those without maggots.1 William Baer is considered to be the founder of modern MDT. While treating soldiers in World War I, he noted the good condition of wounds that had been infested with maggots, and was the first doctor on record to experiment with the use of maggots in treating infections.1 MDT even featured in the recent version of the film ‘Spartacus’. Various species of flies have been used for MDT,1 the most commonly used being Lucilia sericata, a greenbottle blowfly (Figs 1 and 2). This fly is closely related to another greenbottle, L. cuprina, but L. cuprina feeds on live as well as necrotic tissue, which is undesirable in MDT. L. cuprina is commonly named the ‘sheep blowfly’ because it is responsible for fly-strike in sheep, a form of massive, usually rectal myiasis that can kill sheep. A recent article2 suggested that L. cuprina was being used successfully for MDT at the Eugene Marais Hospital Wound Care Centre (EMHWCC). As this would be inconsistent with international experience in MDT and at odds with the usual biology of L. cuprina, it was decided to check the identity of these flies

Diagnosis of community-acquired pneumonia in children: South African Thoracic Society guidelines (part 2)

Background. Accurate diagnosis and attribution of the aetiology of pneumonia are important for measuring the burden of disease, implementing appropriate treatment strategies and developing more effective interventions.Objectives. To produce revised guidelines for the diagnosis of pneumonia in South African (SA) children, encompassing clinical, radiological and aetiological methods.Methods. An expert group was established to review diagnostic evidence and make recommendations for a revised SA guideline. Published evidence was reviewed and graded using the British Thoracic Society grading system.Results. Diagnosis of pneumonia should be considered in a child with acute cough, fast breathing or difficulty breathing. Revised World Health Organization guidelines classify such children into: (i) severe pneumonia; (ii) pneumonia (tachypoea or lower chest indrawing); or (iii) no pneumonia. Malnourished or immunocompromised children with lower chest indrawing should be managed as cases of severe pneumonia. Pulse oximetry should be done, with hospital referral for oxygen saturation <92%. A chest X-ray is indicated in severe pneumonia or when tuberculosis (TB) is suspected. Microbiological investigations are recommended in hospitalised patients or in outbreak settings. Improved aetiological methods show the importance of co-infections. Blood cultures have a low sensitivity (<5%), for diagnosing bacterial pneumonia. Highly sensitive, multiplex tests on upper respiratory samples or sputum detect multiple potential pathogens in most children. However, even in symptomatic children, it may be impossible to distinguish colonising from causative organisms, unless identification of the organism is strongly associated with attribution to causality, e.g. respiratory syncytial virus, Mycobacterium tuberculosis, Bordetella pertussis, influenza, para-influenza or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Investigations for TB should be considered in children with severe pneumonia who have been hospitalised, in a case of a known TB contact, if the tuberculin skin test is positive, if a child is malnourished or has lost weight, and in children living with HIV. Induced sputum may provide a higher yield than upper respiratory sampling for B. pertussis, M. tuberculosis and Pneumocystis jirovecii. Conclusions. Advances in clinical, radiological and aetiological methods have improved the diagnosis of childhood pneumonia

Epidemiology and aetiology of community-acquired pneumonia in children: South African Thoracic Society guidelines (part 1)

Background. Pneumonia remains a major cause of morbidity and mortality among South African (SA) children. Improved immunisation regimens, strengthening of HIV programmes, better socioeconomic conditions and new preventive strategies have influenced the epidemiology of pneumonia. Furthermore, sensitive diagnostic tests and better sampling methods in young children improve aetiological diagnosis.Objectives. To summarise current information on childhood community-acquired pneumonia (CAP) epidemiology and aetiology in children as part of the revised South African Thoracic Society guidelines.Methods. The Paediatric Assembly of the South African Thoracic Society and the National Institute for Communicable Diseases expert subgroup on epidemiology and aetiology revised the existing SA guidelines.The subgroup reviewed the published evidence in their area; in the absence of evidence, expert opinion was accepted. Evidence was graded using the British Thoracic Society (BTS) grading system, and the relevant section underwent peer review.Results. Respiratory viruses, particularly respiratory syncytial virus, are the key pathogens associated with hospitalisation for radiologically confirmed pneumonia in HIV-uninfected children. Opportunistic organisms, including Pneumocystis jirovecii, are important pathogens in HIV-infected infants, while non-typable Haemophilus influenzae and Staphylococcus aureus are important in older HIV-infected children. Co-infections with bacteria or other respiratory viruses are common in hospitalised children. Mycobacterium tuberculosis is common in children hospitalised with CAP in SA.Conclusions. Numerous public health measures, including changes in immunisation schedules and expansion of HIV prevention and treatment programmes, have influenced the epidemiology and aetiology of CAP in SA children. These changes have necessitated a revision of the South African Paediatric CAP guidelines, further sections of which will be published as part of a CME series in SAMJ

Prevention of community-acquired pneumonia in children: South African Thoracic Society guidelines (part 4)

Background. More comprehensive immunisation regimens, strengthening of HIV prevention and management programmes and improved socioeconomic conditions have impacted on the epidemiology of paediatric community-acquired pneumonia (CAP) in South Africa (SA).Objectives. To summarise effective preventive strategies to reduce the burden of childhood CAP.Methods. An expert subgroup reviewed existing SA guidelines and new publications focusing on prevention. Published evidence on pneumonia prevention informed the revisions; in the absence of evidence, expert opinion was used. Evidence was graded using the British Thoracic Society (BTS) grading system.Recommendations. General measures for prevention include minimising exposure to tobacco smoke or air pollution, breastfeeding, optimising nutrition, optimising maternal health from pregnancy onwards, adequate antenatal care and improvement in socioeconomic and living conditions. Prevention of viral transmission, including SARS-CoV-2, can be achieved by hand hygiene, environmental decontamination, use of masks and isolation of infected people. Specific preventive measures include vaccines as contained in the Expanded Programme on Immunisation schedule, isoniazid prophylaxis for tuberculosis, co-trimoxazole prophylaxis for HIV-infected infants and children who are immunosuppressed, and timely diagnosis of HIV, as well as antiretroviral therapy (ART) initiation. HIV-infected children treated with ART from early infancy, and HIV-exposed children, have similar immunogenicity and immune responses to most childhood vaccines as HIV-unexposed infants.Validation. These recommendations are based on available published evidence supplemented by the consensus opinion of SA paediatric experts, and are consistent with those in published international guidelines

A review of biophysical and socio-economic effects of unconventional oil and gas extraction - implications for South Africa

The impacts associated with unconventional oil and gas (UOG) extraction will be cumulative in nature and will most likely occur on a regional scale, highlighting the importance of using strategic decision-making and management tools. Managing possible impacts responsibly is extremely important in a water scarce country such as South Africa, versus countries where more water may be available for UOG extraction activities. This review article explains the possible biophysical and socioeconomic impacts associated with UOG extraction within the South African context and how these complex impacts interlink. Relevant policy and governance frameworks to manage these impacts are also highlighted.The Water Research Commission, South Africa, is thanked for providing funding for this research.http://www.elsevier.com/locate/jenvman2017-12-31hb2017Geolog