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OBJECTIVE: The aim was to contribute to the nutritional well-being of young children living in Duncan Village by investigating factors that influence clinic attendance of mothers and to formulate recommendations for optimisation of accessibility of primary health care (PHC) clinics in the area. DESIGN: PHC clinic accessibility was evaluated by assessing the experiences of mothers who attended clinics in the area as well as the experiences of health care workers (HCWs) in these clinics of service delivery and its recipients (mothers/children), using the focus group technique. The ATLAS/ti program was used to analyse the data in the following steps: preparation and importing of the data, getting to know and coding the data, retrieval and examination of codes and quotations, creation of families and creation of networks. SETTING: Duncan Village, a low socio-economic urban settlement in East London, South Africa. SUBJECTS: Focus group discussions (four to seven participants per group) were conducted with four groups of mothers who do not attend PHC clinics, six with mothers who do attend the clinics (including pregnant women) and four groups of HCWs. RESULTS: Four networks that provide a summary of all the major trends in the data were created. The results clearly indicate that mothers in Duncan Village perceive and/or experience serious problems that make it difficult for them to attend clinic and even prevent them from doing so. These problems include both the way they are treated at the clinics (especially the problem of verbal abuse) as well as the actual services delivered (no medicines, no help, disorganised, long waiting periods, being turned away). The main problem experienced by the HCWs with service delivery seems to be a heavy workload, as well as the fact that many mothers do not come for follow-up visits. CONCLUSION: Efforts to increase the accessibility of PHC clinics in Duncan Village should focus on improving the relationship between mothers and HCWs and the heavy workload experienced by these workers.  相似文献   

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Nineteen dietary and 30 medicinal wild plants used by residents of the Eastern Cape Province of South Africa were investigated for the presence of fumonisin B1 and aflatoxin B1. The plants were extracted in water, and cleanup was undertaken on immunoaffinity cartridges; analysis was by HPLC using fluorescence detection. None of the plant extracts contained detectable levels of aflatoxin B1; however, eight plants, four dietary and four medicinal, were positive for fumonisin B1 at levels ranging from 34 to 524 microg/kg and from 8 to 1553 microg/kg, respectively. The presence of fumonisin B1 was confirmed by LC-MS/MS using positive ion electrospray ionization. Fumonisin B1 provided characteristic fragment ions at m/z 704, 686, 546, 528, 370, and 352 corresponding to sequential loss of H2O and tricarboxylic acid moieties from the alkyl backbone. These results indicate that exposure to fumonisin B1 is much more widespread than initially thought and is the first report of mycotoxin contamination in South African medicinal and dietary wild plants.  相似文献   

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Abstract

Thorough knowledge of cultivated soils is necessary for their informed and sustainable management. This study was carried out to gain a better understanding of cropped soils in the Eastern Cape Province of South Africa. The mineralogical and chemical composition and nutrient status of topsoils collected from homestead gardens and fields of smallholdings in 5 of the 36 magisterial districts where smallholder farming prevails in the Province were determined. These data were supplemented with results of soil analyses conducted by an Analytical Services Laboratory that obtains its samples from the 31 magisterial districts where large‐scale farms are dominant. The soils studied were similar mineralogically, and all had a clay fraction that was dominated by quartz, mica, and/or kaolinite, which is fairly typical for many tropical and subtropical soils. Elemental analysis showed that the soils were generally low to very low in their total content of nutrients, except for sulfur (S), manganese (Mn), zinc (Zn), copper (Cu), and boron (B), reflecting the marine and sedimentary nature of their parent materials. The available nutrient status of the cultivated soils was generally low to very low, especially those found in smallholder fields. This was attributed to low soil organic matter levels and low geological reserves of some nutrients notably phosphorus (P), potassium (K), and calcium (Ca), coupled with continuous cultivation of the lands without adequate nutrient replenishment. Depending on location, 75–100% of the fields tested low in pH, 62–100% were low in organic carbon, 83–100% were low in extractable K, 62–93% were low in extractable Ca, and 79–100% were deficient in available phosphorus. The nutrient status of soils receiving moderate to high amounts of nutrients was generally satisfactory, as revealed by the nutrient content of garden soils found on smallholdings and the fields on large‐scale farms. In all cases, soil pH was low to critically low. The findings are used to propose a soil fertility management strategy for the communal areas of the Province.  相似文献   

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Fire in the fynbos is a complex and much discussed phenomenon, yet little concrete evidence is available on the exact effects of fire on this vegetation type. It is suggested that fire may have been responsible for the elimination of a fynbos tree element, and that a longer period (probably ± 40 years) between fires may be more applicable than the present 8–12 year regime advocated.  相似文献   

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Soil erosion has serious off-site impacts caused by increased mobilization of sediment and delivery to water bodies causing siltation and pollution. To evaluate factors influencing soil erodibility at a proposed dam site, 21 soil samples collected were characterized. The soils were analyzed for soil organic carbon (SOC), exchangeable bases, exchangeable acidity, pH, electrical conductivities, mean weight diameter and soil particles’ size distribution. Cation exchange capacity, exchangeable sodium percentage, sodium adsorption ratio, dispersion ratio (DR), clay flocculation index (CFI), clay dispersion ratio (CDR) and Ca:Mg ratio were then calculated. Soil erodibility (K-factor) estimates were determined using SOC content and surface soil properties. Soil loss rates by splashing were determined under rainfall simulations at 360?mmh?1 rainfall intensity. Soil loss was correlated to the measured chemical and physical soil properties. There were variations in soil form properties and erodibility indices showing influence on soil loss. The average soil erodibility and SOC values were 0.0734?t?MJ?1?mm?1 and 0.81%, respectively. SOC decreased with depth and soil loss increased with a decrease in SOC content. SOC significantly influenced soil loss, CDR, CFI and DR (P??1. Addition of organic matter stabilize the soils against erosion.  相似文献   

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《Biological conservation》1985,32(4):375-382
Following a survey of the carnivores occurring in the Cape Province, it was found that in addition to the large carnivores, two smaller species were also endangered. The serval Felis serval is now considered to be extinct as a viable species in the Province, but it is suggested that reintroductions could be successful. Populations of the spotted-necked otter Lutra maculicollis are still known to occur in the Bushman's, Buffalo and Keiskamma Rivers and in the vicinity of the headwaters of the Orange River system. However, no positive evidence was obtained to show that they occur in any system west of 26° East in the Cape Province. Other than trying to retain suitable water quality in these rivers, little can be done to improve the conservation position of this otter.  相似文献   

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Headwater rivers are the predominant kind of aquatic ecosystem in South Africa’s Cape Floristic Region. Invasion by alien woody taxa (especially Acacia longifolia and Acacia mearnsii) have altered these rivers in recent decades, replacing indigenous vegetation and altering ecosystem functioning. Aliens have been systematically cleared in watercourses since 1995 as part of a national program (“Working for Water”) to increase water production and improve water quality. Cleared sites are mostly left to recover to their pre-invasion state without additional intervention. We compared the vegetation of seven rivers that vary in their extent of invasion and clearing to identify factors limiting recolonization. Dense invasions cleared 3-6 years before the survey differ in vegetation structure and composition from uninvaded or lightly invaded/cleared riparian reaches in the following ways: (1) diminished extent of indigenous trees in the canopy and increased importance of shrubs or reinvading alien trees, (2) reduced species richness, (3) reduced likelihood of occupancy for more than one-third of common, indigenous species, and (4) reduced incidence of indigenous tree regeneration. Overall, indigenous tree regeneration is very low and not disturbance-triggered which will likely result in slow recovery without additional intervention. We recommend focusing active revegetation on common riparian scrub trees (i.e., Metrosideros angustifolia, Brachylaena neriifolia, Brabejum stellatifolium, and Erica caffra). These species tolerate open habitats favored by alien trees, eventually forming closed canopies required by shade-tolerant species. Accelerating establishment of these small trees is likely critical for shifting cleared riparian corridors from a state that favors alien reinvasion. Effective establishment strategies will need to be developed in the context of hydrologic impairment, since alien-invaded rivers in this region typically have reduced flow.  相似文献   

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Soil erosion is a major land degradation problem in South Africa (SA) that has economic, social and environmental implications due to both on-site and off-site effects. High rates of soil erosion by water are causing rapid sedimentation of water bodies, ultimately leading to water crisis in SA. Lots of financial and human resources are channelled towards controlling of soil erosion but unfortunately with little success. The level of soil erosion in a particular area is governed by the site properties. Therefore, it is inappropriate to generalize data on soil erosion at a large-scale spatial context. The literature on soil erosion in SA classifies Eastern Cape Province as a high-erosion-potential area using data collected at a large-scale spatial context. Collecting soil erosion data at a large spatial scale ignores site-specific properties that could influence soil erosion and has resulted in failure of many traditional soil erosion control measures applied in the province. Moreover, scientific principles underlying the processes and mechanisms of soil erosion in highly erodible soils are missing in SA. This review was to find effective soil erosion control measures by having an insight on what happens during soil erosion and how soil erosion occurs in Ntabelanga. The literature suggested that erosion in Ntabelanga could be influenced by both the erosivity and erodibility factors though the erodibility factors being more influential. Soil permeability contrast between the horizons could be influencing the rate and nature of soil erosion. To mitigate the impact of soil erosion in Ntabelanga, efforts should aim to improve the vertical flow capacity in the B horizon. Clay spreading, clay delving, addition of gypsum, deep ploughing and mulching could aid the water permeability problems of the subsurface horizons. However for effective soil management and control option, detailed studies of specific site properties are needed. The generated information can assist in formulating soil erosion policies and erosion control strategies in the Ntabelanga area and SA at large.  相似文献   

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Counts of waders (Aves: Charadrii) in the coastal regions of the south-western Cape, South Africa, were made in the austral summer of 1975/76. Forty-four coastal wetlands and 49 sections of coastline were visited. The total wader population was estimated to be 119,000, of which 103,000 (86%) were Palaearctic migrants. The most abundant Palaearctic species was the curlew sandpiper (Caalidris ferruginea (Pontoppidan)) and the most abundant resident species was the white-fronted plover (Charadrius marginatus Vieillot). No species can be considered to be endangered in the south-western Cape but a decrease in available wader habitat has occurred. South Africa is a Contracting Party to the ‘Ramsar Convention on Wetlands of International Importance, Especially as Waterfowl Habitat’, and therefore should increase its protected wetland habitats. Ten major wetlands in the south-western Cape, containing 68% of the estimated total wader population, are recommended for elevation to nature reserve status. South Africa has a responsibility to protect Palaearctic waders already protected on their Northern Hemisphere breeding grounds.  相似文献   

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Soil pH and nutrient contents influence the uptake and utilization of nutrients required for plant growth. Soil characteristics in the canola-growing areas of the Western Cape Province of South Africa are often very variable. Hence, the major aim of this research was to determine the effects of soil and climatic differences as experienced at different localities on macro- and micronutrient contents and uptake in canola plants fertilized with different nitrogen (N) and sulfur (S) application rates. Plants fertilized with 0, 15, and 30 kg S ha?1 in combination with N rates of 0 and 90 kg ha?1 were sampled at 90 days after planting (DAP) (flowering stage) at Altona, Elsenburg, Langgewens, Roodebloem, and Welgevallen localities in the Western Cape during 2009 2010, and 2011. Nutrient content in canola plants were affected by locality and interactions between locality and N application rates. Sulfur content within the plants remained less than the sufficient quantity of 0.5%, and a dilution effect on elemental concentration in canola especially at greater N rates (plus lack of sufficient S) is apparently evident from the results. The results also reveal that canola S application should match S adsorption capacity of the low pH soils of the Western Cape.  相似文献   

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In the last decade concern has been expressed about the assumed erosion of the beach at St Francis Bay. Evidence is presented on the amount of erosion that has occurred over a seven-year period and the effect this has had on the beach vegetation. An analogy is drawn between this region and other areas along the Eastern Cape coast. Suggestions are put forward to prevent further loss of the shoreline and conserve the valuable ecosystems and the prestigiou  相似文献   

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OBJECTIVE: To describe how urbanisation influences the nutrition and health transition in South Africa by using data from the THUSA (Transition and Health during Urbanisation of South Africans) study. DESIGN: The THUSA study was a cross-sectional, comparative, population-based survey. SETTING: The North West Province of South Africa. SUBJECTS: In total, 1854 apparently healthy volunteers, men and women aged 15 years and older, from 37 randomly selected sites. Pregnant and lactating women, those with diagnosed chronic diseases and taking medication, with acute infections or inebriated were excluded but screened for hypertension and diabetes mellitus. Subjects were stratified into five groups representing different levels of urbanisation in rural and urban areas: namely, deep rural, farms, squatter camps, townships and towns/cities. OUTCOME MEASURES AND METHODS: Socio-economic and education profiles, dietary patterns, nutrient intakes, anthropometric and biochemical nutrition status, physical and mental health indicators, and risk factors for non-communicable diseases (NCDs) were measured using questionnaires developed or adapted and validated for this population, as well as appropriate, standardised methods for the biochemical analyses of biological samples. RESULTS: Subjects from the rural groups had lower household incomes, less formal education, were shorter and had lower body mass indices than those in the urban groups. Urban subjects consumed less maize porridge but more fruits, vegetables, animal-derived foods and fats and oils than rural subjects. Comparing women from rural group 1 with the urban group 5, the following shifts in nutrient intakes were observed: % energy from carbohydrates, 67.4 to 57.3; from fats, 23.6 to 31.8; from protein, 11.4 to 13.4 (with an increase in animal protein from 22.2 to 42.6 g day(-1)); dietary fibre, 15.8 to 17.7 g day(-1); calcium, 348 to 512 mg day(-1); iron from 8.4 to 10.4 mg day(-1); vitamin A from 573 to 1246 mug retinol equivalents day(-1); and ascorbic acid from 30 to 83 mg day(-1). Serum total cholesterol, low-density lipoprotein cholesterol and plasma fibrinogen increased significantly across groups; systolic blood pressure >140 mmHg was observed in 10.4-34.8% of subjects in different groups and diabetes mellitus in 0.8-6.0% of subjects. Women in groups 1 to 5 had overweight plus obesity rates of 48, 53, 47, 61 and 61%, showing an increase with urbanisation. Subjects from group 2 (farm dwellers) showed the highest scores of psychopathology and the lowest scores of psychological well-being. The same subjects consistently showed the lowest nutrition status. CONCLUSIONS: Urbanisation of Africans in the North West Province is accompanied by an improvement in micronutrient intakes and status, but also by increases in overweight, obesity and several risk factors for NCDs. It is recommended that intervention programmes to promote nutritional health should aim to improve micronutrient status further without leading to obesity. The role of psychological strengths in preventing the adverse effects of urbanisation on health needs to be examined in more detail.  相似文献   

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Three lunette dunes occur on the southern shore of a pan on the farm Buffelsfontein above the Great Escarpment in the northeastern part of the Eastern Cape Province, South Africa. The two inner lunettes are formed of silt and clay, and the third of fine sand. The location of these dunes is anomalous as lunette dunes are rare in the wetter parts of the southern African subcontinent. The two inner lunette dunes lie along the downwind margin of a present day pan, while the third lunette is associated with the margin of a large palaeopan. The morphometry of the Buffelsfontein pan/lunette dune series was investigated using aerial photography and field surveys. Sedimentological and geochemical techniques were applied to investigate the lunette and pan floor sediments and to assist in the elucidation of processes responsible for the development of the lunettes. Sedimentological differences in the pan fringing lunettes suggest two very different sediment sources related to changing geomorphic conditions, possibly since the last glacial maximum. The pan/lunette complex offers a unique opportunity to quantify these changes as local rainfall records are available for the past 100 years.  相似文献   

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This study describes the diurnal and seasonal dynamics of the canopy reflectance, water use and water status of Midknight Valencia citrus trees under semi-arid conditions. Hyperspectral canopy reflectance data was collected on 30 trees at monthly intervals over a period of 16 months in a commercial orchard in South Africa. The mean canopy reflectance in the wavelength range 350-2500 nm followed a clear seasonal trend influenced by environmental conditions and tree phenology. Mean monthly reflectance peaked in summer (∼22%) while the lowest value (∼15%) was reached in winter with the seasonal changes in the sun's position accounting for a significant proportion of the variations. A sensitivity analysis of a Penman-Monteith transpiration model showed that water use by individual trees changed by up to 13% when the canopy reflectance was varied over the seasonal range of measured values. This suggested that the seasonal changes in tree water use influenced the seasonal trend of the canopy reflectance. Thus monitoring the canopy reflectance of citrus trees could offer information on the tree water status. To test this, sap flow data of water uptake and loss by the trees were compared with the canopy spectra. Sap flow data showed a heavy reliance by the citrus trees on the internally stored water with up to 25% of the daily total transpiration withdrawn from the trees’ internal water storage pools when soil water was limited. This depletion of internally stored water, and hence the change in tree water status, was detected using spectral indices based on the first order derivatives of the canopy reflectance centered at two and, at most, four spectral bands. We conclude that even if citrus trees are evergreen, their canopy reflectance changes significantly throughout the year with a considerable impact on tree energy balance and water use. In addition, the contribution of the internally stored water to daily transpiration is a possible indicator of drought stress for citrus trees detectable from changes in canopy reflectance and it has potential applications in irrigation scheduling using canopy level spectral information.  相似文献   

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