Oxygen and temperature influence the distribution of deepwater Cape hake Merluccius paradoxus in the southern Benguela: a GAM analysis of a 10-year time-series

Generalised additive models (GAMs) were applied to survey data to assess the influence of dissolved oxygen, water temperature and year of sampling upon the presence/absence of small (≤15 cm TL), medium (16–34 cm TL) and large (≥35 cm TL) size classes of deepwater Cape hake Merluccius paradoxus captured off the west coast of South Africa. Data were obtained from surveys using the RV Dr Fridtjof Nansen conducted in 2003 and from 2005 to 2013 during summer (January–February). Among the variables investigated, oxygen was the most important for the small size class (juveniles), with both low and high constraints (two-sided, ‘just right’ option), whereas for the medium and large size classes the oxygen effects were one-sided (avoiding lows). This finding, in combination with other published information, suggests that the Orange Banks is a nursery ground for juvenile M. paradoxus and that the area covered by this nursery ground can vary with the optimal oxygen concentration. The temperature constraint was generally wider and weaker than that for oxygen, being two-sided for the small and medium hake and one-sided (avoiding highs) for the large hake. The medium hake displayed the greatest tolerance to the investigated variables, which resulted in the widest distribution for this size class. Temperature, oxygen and sampling year play an important role in determining the distribution of M. paradoxus, but details of the biology (life cycle) of the species, such as its pelagic–demersal transition and associated movements, are no less important.publishedVersio

LiDAR for Atmosphere Research over Africa (LARA)

International audienceThis paper describes the LIDAR for atmosphere research over Africa and current initiatives being undertaken in South Africa. A mobile LIDAR system is being developed at the Council for Scientific and Industrial Research (CSIR) National Laser Centre (NLC), Pretoria (25°5 ′ S;28°2 ′ E), South Africa, for remote sensing the atmosphere. The initial results conclude that the system is capable of providing aerosol/cloud backscatter measurements for the height region from ground to 40 km with a 10 m vertical height resolution

Course of psychotic experiences and disorders among apprentice traditional health practitioners in rural South Africa:3-year follow-up study

Background: Culture is inevitably linked with the experience, interpretation and course of what modern biomedicine understands to be psychotic symptoms. However, data on psychoses in low- and middle-income countries are sparse. Our previous study showed that psychotic and mood-related experiences, symptoms and disorders are common among individuals who had received the ancestral calling to become a traditional health practitioner (THP) in rural KwaZulu-Natal, South Africa. Our related ethnographic study suggested that ukuthwasa (the training to become a THP) may positively moderate these calling-related symptoms. As far as we know, no research has been conducted into the course of psychiatric symptoms among apprentice THPs. Objective: We studied the course of psychotic experiences, symptoms and disorders among apprentice THPs. We also assessed their level of functioning and expanded our knowledge on ukuthwasa. Materials and methods: We performed a 3-year follow-up of a baseline sample of apprentice THPs (n = 48). Psychiatric assessments (CAPE, SCAN), assessment of functioning (WHODAS) and a semi-structured qualitative questionnaire were completed for 42 individuals. Results: At 3-year follow-up, psychotic experiences were associated with significantly less distress and there was a reduction in frequency of psychotic symptoms compared to baseline. The number of participants with psychotic disorders had decreased from 7 (17%) to 4 (10%). Six out of seven participants (86%) with a psychotic disorder at baseline no longer had a psychiatric diagnosis at follow-up. Although the mean level of disability among the (apprentice) THPs corresponded with the 78th percentile found in the general population, 37 participants (88%) reported no or mild disability. Forty-one participants (98%) reported that ukuthwasa had positively influenced their psychiatric symptoms. Conclusion: In rural KwaZulu-Natal, psychotic experiences, symptoms and disorders have a benign course in most individuals who are undergoing the process of becoming a THP. Ukuthwasa may be an effective, culturally sanctioned, healing intervention for some selected individuals, potentially because it reframes distressing experiences into positive and highly valued experiences, reduces stigma, and enhances social empowerment and identity construction. This implies that cultural and spiritual interventions can have a positive influence on the course of psychosis

Track D Social Science, Human Rights and Political Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

If not now, when? Time for the European Union to define a global health strategy

Speakman, E. M., McKee, M., & Coker, R. (2017). If not now, when? Time for the European Union to define a global health strategy. Lancet Global Health, 5(4), e392-e393. https://doi.org/10.1016/S2214-109X%2817%2930085-

Determining spatial and temporal variability in quantity and quality of vegetation for estimating the predictable sustainable stocking rate in the semi-arid savanna

This study assessed the importance of spatial and temporal variation in plant quality and quantity for determining sustainable stocking rates in game, commercial and communal ranches in semi-arid savanna of the Northern Cape Province, South Africa, in wet and dry seasons over a two-year period. We focussed on variation in plant biomass, phosphorus (P), crude protein (CP) concentrations and dry matter digestibility as parameters most likely to affect sustainable stocking rates. Habitat type had greater effects on plant quality, plant biomass and species composition than management type. The commercially-managed area had the highest tree density in the rocky habitat and lower plant quality than other management types. All of these features indicate that land degradation is occurring on commercial ranches in spite of rotational grazing and lower stocking density than on communal ranches. We recommend that commercial ranchers should introduce a greater variety of stock and/or game to reduce selective grazing of certain plant species. Quality measures (CP and P) gave more conservative predictions of stocking density than biomass. In this region of the Northern Cape, seasonally-inundated pan habitats are particularly valuable in spite of low-standing crop because they have the highest year-round quality. Contrastingly, ranchers should only lightly stock open savanna habitats, in spite of high standing biomass, because they have low vegetation quality and may be particularly susceptible to degradation and invasion by poisonous and unpalatable plants. Copyright © NISC Pty Ltd.Articl

Effects of herbivore exclosures on variation in quality and quantity of plants among management and habitat types in a semiarid savanna

The effects of grazing on plant biomass, plant quality, species evenness, species diversity and species composition were determined among management types (communal, commercial and game) and among habitat types (open savanna, rocky and pan) in a semiarid savanna in South Africa. Over three growing seasons we compared fenced and unfenced plots among all management and habitat types. Fenced plots had greater mean plant height as well as higher crude protein (CP) and phosphorus (P) yields (= concentration × biomass). The only significant difference in species composition between fenced and unfenced plots was observed in the pan habitat type during the third growing season. Negative effects of grazing were more pronounced in the commercially managed area than under other management types, although the higher abundance of poisonous plants under communal management is of considerable concern. The open savanna habitat had the highest plant biomass and lowest CP and P levels, while the reverse was true for the pan habitat type. Most parameters assessed showed significant effects between fenced and unfenced plots towards the end of the study only because species composition in fenced plots was altered by competition between species normally suppressed by grazing. © NISC (Pty) Ltd.Articl

Effects of herbivore exclosures on variation in quality and quantity of plants among management and habitat types in a semiarid savanna

The effects of grazing on plant biomass, plant quality, species evenness, species diversity and species composition were determined among management types (communal, commercial and game) and among habitat types (open savanna, rocky and pan) in a semiarid savanna in South Africa. Over three growing seasons we compared fenced and unfenced plots among all management and habitat types. Fenced plots had greater mean plant height as well as higher crude protein (CP) and phosphorus (P) yields (= concentration x biomass). The only significant difference in species composition between fenced and unfenced plots was observed in the pan habitat type during the third growing season. Negative effects of grazing were more pronounced in the commercially managed area than under other management types, although the higher abundance of poisonous plants under communal management is of considerable concern. The open savanna habitat had the highest plant biomass and lowest CP and P levels, while the reverse was true for the pan habitat type. Most parameters assessed showed significant effects between fenced and unfenced plots towards the end of the study only because species composition in fenced plots was altered by competition between species  normally suppressed by grazing.Keywords: grazing, herbivory, plant biomass, plant quality, rangeland managementAfrican Journal of Range & Forage Science 2010, 27(1): 1–

Using faecal profiling to assess the effects of different management types on diet quality in semi-arid savanna

We used faecal profiling to assess diet quality of animals under three different management types in a semi-arid savanna, northwest of Kimberley, Northern Cape, South Africa. The levels of faecal crude protein (FCP) and faecal phosphorus (FP) of free-ranging springbok (Antidorcas marsupialis) and blue wildebeest (Connochaetes taurinus) on a game ranch, goats and cattle grazing in a communally-managed area, as well as cattle grazing under commercial management were determined in the wet and dry seasons over a period of two years. Plant and soil analyses were also conducted. Goats had the highest FCP and FP of all species in all seasons during the study. It appeared that selective feeders (goats and springbok) and short-grass feeders (wildebeest) do not suffer from low forage quality because their FCP and FP levels were above critical values during all seasons. Contrastingly, cattle need nutrient supplementation because their FCP and FP were below critical nutritional values during the dry seasons. Plant and soil chemical characteristics, especially soil P, had an influence on faecal quality during the study. Clay pans provide an important habitat because of the high soil quality and, consequently, high diet quality. Our surprising finding that faecal CP levels were higher under communal management than under commercial management may be ascribed to higher nutrient deposition (due to higher stocking rates) and greater diet selectivity available to free-ranging animals under communal management. Higher faecal CP and P levels in game animals may also be ascribed to unrestricted movement and, consequently, greater access to palatable plants. The results of this study demonstrate the value of faecal profiling for management of semi-arid savanna livestock and game. Copyright © NISC Pty Ltd.Articl