Beekeeping and crop farming integration for sustaining beekeeping cooperative societies: a case study in Amathole District,South Africa

Beekeeping has been used with success in several parts of the world to address pervasive poverty. In the last 15 years, the initiative had been used in South Africa; although no evidence of sustainable projects have been found . This study examined the challenges faced by some of the beekeeping cooperative societies (BKCSs) from Ngqushwa, Mnquma and Raymond Mhlaba in the Amathole District of the Eastern Cape Province, South Africa. Data were collected between September and December 2014 and August and November 2015 from eight BKCSs in three local municipalities, using a random sampling technique. The findings revealed poor farm planning and orientation on the part of the farmers, pilfering from and vandalising of apiaries, poor skills training, poor management techniques, and weak agricultural extension support. The study suggests an integrated beekeeping and crop farming model as a viable option.     

Geochemistry of Karroo dolerite sills in the Calvinia district,Western Cape Province,South Africa

Two Karroo dolerite sills display chemical and mineralogical variation compatible with cumulus enrichment. The Blaauwkrans sill is an olivine tholeiite and contains a central zone slightly enriched in olivine, plagioclase and clinopyroxene. The thicker Hangnest sill is a quartz tholeiite and shows evidence of crystal settling and has a lower zone enriched in cumulus orthopyroxene and plagioclase.The two sills differ quite markedly in their trace element compositions, with the Hangnest magma enriched by a factor of two in LIL elements (Rb, Ba, Nb, Zr, Y) relative to the Blaauwkrans magma. The Hangnest magma contained extremely low Ni contents (3–5 ppm), whereas the Blaauwkrans magma contained higher but more normal Ni (100–110ppm). Such contrasting trace element compositions preclude any simple genetic relationship between the two Karroo magmas but they may be related either through a common parent or are derivatives from separate parental magmas.South African Contribution No. 24 to the International Geodynamics Project     

Estimations of climate change impacts on crop production in the Republic of Moldova

Statistical methods for assessing crop sensitivity and vulnerability to climate change in Moldova were demonstrated and the following procedures were discussed: (1) projections of likely agroclimatic change; (2) assessments of crop sensitivity to climate change; and (3) assessments of the impact of climate change on crops. In order to predict the future agroclimate, key meteorological variables were transformed statistically to correspond to changes in plants' heat and water supply characteristics. Sensitivity of crop production was examined for corn and winter wheat. By combining the agroclimatic changes with crop response, possible impacts have been estimated and form a basis for possible adaptation strategies. It was shown that regional climate change can result in elevated aridity of Moldova's territory, especially during periods of crop growth. Cultivation of cereal crops in new agroclimatic conditions without adaptation measures will negatively affect yields, especially of winter wheat, whose yield decrease may be 18–39% by 2020s and 22–50% by 2050s. Corn yields may increase by 0–3% and 1–6%, respectively. As an example of adaptation, it is shown that the use of an increased number of late hybrids results in a 25–35% increase in corn yields. This revised version was published online in July 2006 with corrections to the Cover Date.     

Flooding trends and their impacts on coastal communities of Western Cape Province,South Africa

Climate change-induced extreme weather events have been at their worst increase in the past decade (2010–2020) across Africa and globally. This has proved disruptive to global socio-economic activities. One of the challenges that has been faced in this regard is the increased coastal flooding of cities. This study examined the trends and impacts of coastal flooding in the Western Cape province of South Africa. Making use of archival climate data and primary data from key informants and field observations, it emerged that there is a statistically significant increase in the frequency of flooding and consequent human and economic losses from such in the coastal cities of the province. Flooding in urban areas of the Western Cape is a factor of human and natural factors ranging from extreme rainfall, usually caused by persistent cut off-lows, midlatitude cyclones, cold fronts and intense storms. Such floods become compounded by poor drainage caused by vegetative overgrowth on waterways and land pollution that can be traced to poor drainage maintenance. Clogging of waterways and drainage systems enhances the risk of flooding. Increased urbanisation, overpopulation in some areas and non-adherence to environmental laws results in both the affluent and poor settling on vulnerable ecosystems. These include coastal areas, estuaries, and waterways, and this worsens the risk of flooding. The study recommends a comprehensive approach to deal with factors that increase the risk of flooding as informed by the provisions of both the Sustainable Development Goals framework and the Sendai Framework for Disaster Risk Reduction 2015–2030 in a bid to de-risking human settlement in South Africa.

     

Late Quaternary environmental phases in the Eastern Cape and adjacent Plettenberg Bay-Knysna region and Little Karoo, South Africa

Four major climato-environmental phases have been identified in the Eastern Cape, Plettenberg Bay-Knysna region and Little Karoo between somewhat before ∼40 000 cal. a BP and the present: the Birnam Interstadial from before 40 000 cal. a BP until ∼24 000 cal. a BP; the Bottelnek Stadial (apparently equating with the Last Glacial Maximum) from ∼24 000 cal. a BP until before ∼18 350 cal. a BP; the Aliwal North (apparently equating with the Late Glacial) from before ∼18 350 cal. a BP until ∼11 000 cal. a BP; the Dinorben (apparently equating with the Holocene) from ∼11 000 cal. a BP until the present. The evidence for, and the characteristics of, these phases is briefly described.     

Late Quaternary glaciation in Southern Africa: moraine ridges and glacial deposits at Mount Enterprise in the Drakensberg of the Eastern Cape Province,South Africa

Late Quaternary moraines and diamictons containing striated clasts are described from near Elliot in the Drakensberg of South Africa. An equilibrium line altitude (ELA) of 2109 m is suggested for the palaeoglacier associated with the innermost moraine. This glacier was fed by a very extensive snowblow area and the ELA may reflect the temperature–precipitation–wind ELA rather than the temperature–precipitation ELA and be considerably below the ‘regional’ ELA. Mean annual air temperatures when glaciation occurred were probably at least 10.0°C below those of the present. Copyright © 2001 John Wiley & Sons, Ltd.     

Geochemical Evaluation of the Permian Ecca Shale in Eastern Cape Province,South Africa: Implications for Shale Gas Potential

Shale gas has been the exploration focus for future energy supply in South Africa in recent time. Specifically, the Permian black shales of the Prince Albert, Whitehill, Collingham, Ripon and Fort Brown Formations are considered to be most prospective rocks for shale gas exploration. In this study,outcrop and core samples from the Ecca Group were analyzed to assess their total organic carbon(TOC), organic matter type, thermal maturity and hydrocarbon generation potential. These rocks have TOC ranging from 0.11 to 7.35 wt%. The genetic potential values vary from 0.09 to 0.53 mg HC/g,suggesting poor hydrocarbon generative potential. Most of the samples have Hydrogen Index(HI) values of less than 50 mg HC/g TOC, thus suggesting Type-Ⅳ kerogen. Tmax values range from 318℃ to601℃, perhaps indicating immature to over-maturity of the samples. The vitrinite reflectance values range from 2.22% to 3.93%, indicating over-maturity of samples. Binary plots of HI against Oxygen Index(OI), and HI versus Tmax show that the shales are of Type II and mixed Type Ⅱ-Ⅲ kerogen.Based on the geochemical data, the potential source rocks are inferred as immature to over-matured and having present-day potential to produce gas.     

Size variation in the Cape dune molerat (Bathyergus suillus) and late Quaternary climatic change in the southwestern Cape Province, South Africa

Within their historic range at the southwestern tip of Africa, Cape dune molerats (Bathyergus suillus) tend to be significantly larger in areas of higher rainfall. They also tend to be large in late Quaternary fossil samples associated with independent evidence for relatively moist climate and small in samples associated with evidence for relatively dry conditions. Together with sedimentologic/geomorphic and other faunal observations, fluctuations in fossil dune molerat size imply that the regional climate was very moist during an early late Quaternary interval corresponding to marine isotope stage 4 (74,000 to 59,000 yr B.P.) or perhaps to substage 5b or 5d (centered on 110,000 and 90,000 yr B.P., respectively.) It was comparably moist again from roughly 14,000 to 8,000 yr B.P., somewhat drier than at present from about 8000 until 4000 yr B.P., and mainly near the modern average after 4000 yr B.P. Together, the modern and fossil data suggest that dune molerat size is a reliable index of past precipitation, but it may not be useful for revealing extremely arid conditions because these seem to be associated with depositional/occupational gaps in most local paleontological/archeological sites.     

Dealing with climate change and other stressors: small-scale coffee farmers in the Fero-two Peasant Association in the Wensho district,southern Ethiopia

GeoJournal - Drawing on evidence from in-depth interviews and a household survey, the paper provides evidence on the farmers’ challenges in production, marketing and prices as well as how...     

Variations in Isochore Thickness of the Ecca Sediments in the Eastern Cape Province of South Africa, as Deduced from Gravity Models

Gravity modelling was carried out along five profiles that traverse the Eastern Cape Province of South Africa in order to determine the depositional surface and isochore thickness of the Ecca sediments.Gravity models of the subsurface rock density reveal that the Ecca Group has a maximum vertical thickness of about 3215 ± 160 m.The maximum depositional surface(elevation)above sea level for the Ecca sediments is about 500 m,whilst the depth below sea level reaches about10000 m.Correlation of the isochore thickness maps with the depositional surfaces shows that the sediments in the basement highs were subsided,deformed,eroded and deposited in the basement lows.The basement highs served as the source area(s) for the sediments in the basement lows,thus basement highs are characterized with thin sediment cover whilst the lows have thick sediment cover.     

Lower Cretaceous deposit reveals first evidence of a post-wildfire debris flow in the Kirkwood Formation,Algoa Basin,Eastern Cape,South Africa

The Algoa Basin is an onshore rift basin filled by an Upper Mesozoic non-marine and shallow marine sedimentary sequence. The middle unit of this clastic succession is assigned to the Lower Cretaceous Kirkwood Formation, known to host a wealth of plant and animal fossils together with poorly documented lignites, amber and charcoal clasts. This study is motivated by the growing interest in the impact of wildfires on the palaeoenvironment during the high-oxygen, Cretaceous world. It has been hypothesised that frequent and severe Cretaceous wildfires triggered large-scale non-marine denudation events, altering the sedimentation dynamics and influencing the evolution of ecosystems. In order to investigate this phenomenon, charcoal-bearing sedimentary rocks and plant fossil assemblages of the Kirkwood Formation have been studied at the Bezuidenhouts River locality, ∼50 km north of Port Elizabeth (Eastern Cape, South Africa).Detailed field observations of the sedimentary facies suggest that deposition occurred in a meandering fluvial environment with mature, vegetated floodplains. Depositional trends within a charcoal-rich bed (i.e., stratification, flattening and decrease in charcoal clast size down-current) indicate that a charcoal-rich debris flow, linked to a post-wildfire flood event, became diluted by fluvial flow. Palaeocurrent indicators (e.g., orientation of fossil logs) suggest unidirectional currents from SW to NE, which are somewhat inconsistent with the previously reported regional palaeocurrent directions in the Kirkwood Formation.To gain insights into the fire-influenced dynamics of the Early Cretaceous ecosystems, the macro-plant fossil assemblages of the Kirkwood Formation were considered, with reference to the responses of modern plant analogues to wildfire. Of the plant orders reported from macrofossils of the Kirkwood Formation, the Cycadales, Pinales and Filicales, are known to have produced large woody or fibrous trunks and stems, or in the case of the Bennettitales more densely branched, divaricate architectures, and are likely to have provided the bulk of fuel for wildfires, with fern elements dominating groundcover niches. The particular role of these plants in the Early Cretaceous wildfire palaeoecology of the Algoa Basin is a topic for an ongoing study, but the Bezuidenhouts River locality appears to record the aftermath of a severe crownfire that led to mass tree mortality.     

Metamorphism of the Permo-Triassic Cape Fold Belt and its basement, South Africa

Summary  The Permo-Triassic Cape Fold Belt around the southern tip of Africa consists of a thick sequence of Palaezoic siliciclastic sedimentary and pre-Cape basement rocks believed to be of Pan-African age. Both the basement rocks and the supracrustal rocks of the Cape Supergroup display only low metamorphic grades. Application of chlorite, chlorite-chloritoid Fe-Mg exchange, and calcite-graphite carbon isotope geothermometry to rocks from the unconformable contact between pre-Cape basement and the Cape Supergroup made it possible to distinguish pre-Cape and syn-Cape metamorphic overprints. During Pan-African metamorphism temperatures of up to middle greenschist facies conditions (around 400 °C) were reached, whereas lowermost greenschist facies conditions (around 300 °C) were not exceeded during the 220–290 Ma Cape orogeny. In the past, most if not all of the pre-Cape basement rocks, which form the Pan-African Saldania Belt, were considered to be of Neoproterozoic age. A hiatus of about 100 °C observed between two adjacent limestone horizons that previously had been grouped together into a single formation at the bottom of the allegedly Neoproterozoic Kango Group indicates that almost all of this group is syn- to post-orogenic with respect to the Pan-African orogeny. A revision of the stratigraphy of the Kango Group is therefore suggested. Only its lowermost member is truly Pan-African and probably related to about 620–740 Ma post-Sturtian cap carbonates in other Pan-African belts of southern Africa. The remainder of the Kango Group reflects the successive development of two stages of orogen-related intra-continental basins: The older stage led to a typical syn-orogenic foreland basin related to tectonic loading in the Gariep and Damara orogenic belts further north(west) between 570 and 540 Ma; the younger is believed to have formed either a further foreland basin or an intra-orogen pull-apart basin caused by later tectonic loading in the Ross orogenic belt and its continuation into the southern Saldania Belt between 510 and 480 Ma. Received May 7, 2000;/revised version accepted January 15, 2001     

The 1992 drill core from the Kalkkop impact crater, Eastern Cape Province, South Africa: stratigraphy, petrography, geochemistry and age

New drill core data are provided which support earlier interpretations that the Kalkkop structure, a 600–630 m wide, near-circular feature south-southwest of Graaff-Reinet in the Eastern Cape Province of South Africa, is a meteorite impact crater. Shock metamorphosed clasts in suevitic crater fill and Re---Os isotope data of this breccia indicate the presence of a minor (0.05%) meteoritic component in the suevite. The new data come from a 1992 borehole, which transected the complete crater fill and extended from about 160 to 380 m depth into the sedimentary basement belonging to the Koonap Formation of the Beaufort Group (Karoo Supergroup). Dyke breccias were found in the otherwise coherent Beaufort Group sediments forming the floor to the Kalkkop Crater. Mostly narrow zones of different breccia types, including injections of lithic impact breccia, a possible pseudotachylite veinlet and cataclasite occur predominantly in an approximately 65 m wide zone below the crater floor, with a few other cataclasite occurrences found lower down in the basement. Stratigraphical crater constraints provide information for the depth-diameter scaling and breccia volumes associated with such small, bowl-shaped impact craters formed in sedimentary targets.U---Th series dating of limestone samples from near the top and the bottom of the crater sediment fill constraints the age of the Kalkkop impact event to about 250 ± 50 ka, similar to the age of the Pretoria Saltpan impact crater, also located in South Africa. The variety of different breccia types (polymict and monomict impact breccias; local formations of pseudotachylitic and cataclastic breccias) observed in the crater fill of the Kalkkop Crater indicates the need to carefully distinguish different breccia types in order to assess the respective importance of each formation.     

Lithostratigraphy, Sedimentology, and Provenance of the Balfour Formation (Beaufort Group) in the Fort Beaufort–Alice Area, Eastern Cape Province, South Africa

Abstract: The Balfour Formation has a pronounced lithological variation that is characterized by alternating sandstone- and mudstone-dominated members. The sandstone-dominated Oudeberg and Barberskrans Members are composed of lithofacies that range from intraformational conglomerates to fine-grained sediments, whereas the mudstone-dominated members (Daggaboersnek, Elandsberg, and Palingkloof) are dominated by the facies Fm and Fl. Petrography, geochemistry, and a paleocurrent analysis indicated that the source rock of the Balfour Formation was to south east and the rocks had a transitional/dissected magmatic arc signature. The sandstones-rich members were deposited by seasonal and ephemeral high-energy, low-sinuous streams, and the fine-grained-rich members were formed by ephemeral meandering streams. The paleoclimates have been equated to present temperate climates; they were semiarid becoming arid towards the top of the Balfour Formation. This has been determined by reconstructing the paleolatitude of the Karoo Basin, geochemistry, paleontology, sedimentary structures, and other rock properties, like color.     

Institutions,indigenous peoples,and climate change adaptation in the Canadian Arctic

GeoJournal - Climate change impacts on Indigenous peoples in remote regions pose unique institutional challenges and opportunities for governments. Reducing vulnerability and enabling collaborative...     

A Duplex Model for the Eastern Cape Fold Belt? Evidence from the Palaeozoic Witteberg and Bokkeveld Groups (Cape Supergroup), Near Steytlerville, South Africa

The eastern part of the Cape Fold Belt, near Steytlerville, South Africa, reveals a typical pattern of numerous, north-verging thrust faults and associated folds, interpreted as part of a large duplex structure that formed along the southern margin of Gondwana during the Late Palaeozoic. Steeply-dipping fore- and backthrusts occur in the Bokkeveld Group (middle Cape Supergroup), where strata are composed of predominantly argillaceous rocks, whereas in the more arenaceous Witteberg Group (upper Cape Supergroup) there are fewer recognizable and less closely-spaced thrusts. Open style folds characterize areas in which the Bokkeveld Group crops out, but in areas of Witteberg outcrop, folds, especially those adjacent to thrusts, are often overturned.In spite of a general absence of marker horizons, a displacement of at least 500 metres can be inferred for one prominent thrust, the Jackalsbos thrust. This fault, the northernmost in the area investigated, is probably the sole thrust in the duplex structure, linked through southward-dipping imbricates to a projected roof thrust (the Baviaanskloof thrust) cropping out immediately south of the study area.Displacements on imbricates within the duplex are difficult if not impossible to measure, but the net effect is certainly accumulative and incremental. Truncation by a roof thrust and subsequent erosional processes may explain why so few of the many thrusts so far identified in the eastern part of the fold belt can be successfully mapped, and their displacements measured. Normal and strike-slip faults, less common than thrust faults, formed during extensional tectonism related to the breakup of Gondwana, during the Mesozoic.     

Origin and evolution of major salts in the Darling pans,Western Cape,South Africa

Sediment and water samples from 12 saline pans on the semi-arid west coast of South Africa were analysed to determine the origin of salts and geochemical evolution of water in the pans. Pans in the area can be subdivided into large, gypsiferous coastal pans with 79–150 g/kg total dissolved salt (TDS), small inland brackish to saline (2–64 g/kg TDS) pans and small inland brine (168-531 g/kg TDS) pans that have a layer of black sulphidic mud below a halite crust. The salinity of coastal pan waters varies with the seasonal influx of dilute runoff and dissolution of relict Pleistocene marine evaporite deposits. In contrast, inland pans are local topographic depressions, bordered on the north by downslope lunette dunes, where solutes are concentrated by evaporation of runoff, throughflow and groundwater seepage. The composition of runoff and seepage inflow waters is determined by modification of coastal rainfall by weathering, calcite precipitation and ion exchange reactions in the predominantly granitic catchment soils. Evaporation of pan waters leads to precipitation of calcite, Mg–calcite, dolomite, gypsum and halite in a distinct stratigraphic succession in pan sediments. Bicarbonate limits carbonate precipitation, Ca limits gypsum precipitation and Na limits halite precipitation. Dolomitisation of calcite is enhanced by the high Mg/Ca ratio of brine pan waters. Brine pan waters evolve seasonally from Na–Cl dominated brines in the wet winter months to Mg–Cl dominated brines in the dry summer months, when 5–20 cm thick halite crusts cover pan surfaces. Pan formation was probably initiated during a drier climate period in the early Holocene. More recent replacement of natural vegetation by cultivated land may have accelerated salt accumulation in the pans.     

Formation of modern dolomite in hypersaline pans of the Western Cape,South Africa

Authigenic calcite and dolomite and biogenic aragonite occur in Holocene pan sediments in a Mediterranean‐type climate on the western coastal plain of South Africa. Sediment was analysed from a Late Pleistocene coastal pan at Yzerfontein and four Holocene inland pans ranging from brackish to hypersaline. The pans are between 0·08 and 0·14 km² in size. The δ¹⁸O_PDB values of carbonate minerals in the pan sediments range from ?2·41 to 5·56‰ and indicate precipitation from evaporative waters. Covariance of total organic content and percentage carbonate minerals, and the δ¹³C_PDB values of pan carbonate minerals (?8·85 to ?1·54‰) suggest that organic matter degradation is a significant source of carbonate ions. The precipitation of the carbonate minerals, especially dolomite, appears to be mediated by sulphate‐reducing bacteria in the black sulphidic mud zone found in the brine‐type hypersaline pans. The knobbly, sub‐spherical texture of the carbonate minerals suggests that the precipitation of the carbonate minerals, particularly dolomite, is related to microbial processes. The ⁸⁷Sr/⁸⁶Sr ratios of pan carbonate minerals (0·7108 to 0·7116) are slightly higher than modern sea water and indicate a predominantly sea water (marine aerosol) source for calcium (Ca²⁺) ions with relatively minor amounts of Ca²⁺ derived from the chemical weathering of bedrock.