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Analysis of Stable Isotopes of Xylem Water from Plantation Trees in E. Transvaal and Zululand Indicate they Utilised Ground water During Drought of 1992
Item type: Journal Article • Journal: South African Forestry Journal • Authors: J.J. Midgley --- , South Africa S. Talma --- , South Africa D. Scott --- , South Africa B. Olbrich --- , South Africa G.F. van Wyk --- , South AfricaWe investigated the stable isotopic signature of xylem sap of mature plantation trees and the associated ground water at sites in Zululand and E. Transvaal. The survey took place mainly during the drought of 1992. Results indicated a range of... -
RELATIVELY NEGATIVE δ13C RATIOS OF MESOZOOPLANKTON IN THE SUNDAYS RIVER ESTUARY, COMMENTS ON POTENTIAL CARBON SOURCES
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: H.L. Jerling --- Department of Zoology, South Africa T.H. Wooldridge --- Department of Zoology, South AfricaMesozooplankton, submergent and fringing macrophytes and particles suspended in the water column in the Sundays River estuary South Africa were analyzed for δ13C isotope ratios. Highly negative values (−28.3‰ to −32.0‰) for the mesozooplankton species suggest the possibility of phytoplankton... -
A COMPARISON OF THE FOOD SOURCES OF STONEFLIES (PLECOPTERA) FROM AN OPEN-AND A CLOSED-CANOPY HEADWATER STREAM IN SOUTH AFRICA USING STABLE-ISOTOPE TECHNIQUES
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: E. Reynolds --- , , South Africa C. de Villiers --- , , B. R. Davies --- , , South AfricaThe effects of different local food resources on the diets of some filipalpian stonefly nymphs (Aphanicerca spp.) were investigated. Animals from two headwater reaches, one primarily allochthonously driven and the other an open-canopied autochthonous-based system were compared. However, gut and... -
Stable isotope (∂13C) composition of the food web of the temperate Kariega estuary (Eastern Cape)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW FronemanStable isotope (∂13C) composition of the food web in the temperate Kariega estuary in summer and winter was analysed to determine the trophic relationships between 19 taxa. There was no seasonality in the stable isotope ratios of the dominant producers... -
Biomagnification of mercury in fish from Thruston Bay, Napoleon Gulf, Lake Victoria (East Africa)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LindaM Campbell JS Balirwa DG Dixon RE HeckyTotal mercury concentrations (THg) were measured in fish from Thruston Bay, Napoleon Gulf in northern Lake Victoria between 1998 and 2000. Total Hg concentrations in Lates niloticus (Nile perch) and Oreochromis niloticus (Nile tilapia) ranged from 10.6 to 77.5ng g–1... -
The primary carbon sources utilised by fishes in the Mngazi and Mngazana estuaries, South Africa: a preliminary assessment
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Sekiwe Mbande William Froneman AlanK WhitfieldA number of studies have used stable carbon isotopes to analyse aspects of the food web structure in South African estuaries but none has compared mangrove and non-mangrove estuarine food webs. This study compares the primary carbon sources utilised by... -
Food web structure in three contrasting estuaries determined using stable isotope (∂13C) analysis
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW Froneman --- Department of Zoology and Entomology, South AfricaFood web structure in three contrasting estuaries, the freshwater-deprived Kariega, the freshwater-dominated Great Fish River and the temporarily open/closed Kasouga estuary, along the south-east coast of southern Africa was investigated in summer (1–4 November) 2000 by employing stable carbon (∂13C)... -
Nature of suspended particulate matter and concentrations of heavy metals in sediment in the southern part of Lake Victoria, East Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JF Machiwa --- Department of Aquatic Environment and Conservation, TanzaniaThe concentrations of metals in bottom sediment in the Tanzanian waters of Lake Victoria and the nature of suspended particulate matter (SPM) were analysed. The objective of the study was to compare levels of metals in sediment from different locations... -
Reeds as indicators of nutrient enrichment in a small temporarily open/ closed South African estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LRD Human --- Department of Botany, South Africa JB AdamsThis study investigated the use of δ15N levels in Phragmites australis reeds as an indicator of nutrient input into the small temporarily open/closed East Kleinemonde Estuary, Eastern Cape, South Africa. Nutrient (NH4 and SRP) concentrations decreased from the bank towards... -
Flood effects on trophic linkages of selected fish species in the littoral zone of the St Lucia estuarine system, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Peer --- School of Life Sciences, South Africa NK Carrasco --- School of Life Sciences, South Africa R Perissinotto --- School of Life Sciences, South Africa SJ du Plooy --- School of Life Sciences, South AfricaThe St Lucia Estuary, a UNESCO World Heritage Site, has experienced prolonged mouth closure since 2002. Until recently it was hypersaline, but heavy rainfall between October 2010 and January 2011 led to a large overall decrease in salinity. A stable... -
Feeding habits and food partitioning between three commercial fish associated with artificial reefs in a tropical coastal environment
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Mablouké --- Université de la Réunion, Laboratoire ECOMAR FRE 3560 (CNRS/INEE/UR), France J Kolasinski --- IsoEnvironmental cc, Botany Department, South Africa M Potier --- IRD, UMR 212 EME (IRD/IFREMER/UM2), France A Cuvillier --- Université de la Réunion, Laboratoire ECOMAR FRE 3560 (CNRS/INEE/UR), France G Potin --- Université de la Réunion, Laboratoire ECOMAR FRE 3560 (CNRS/INEE/UR), France L Bigot --- Université de la Réunion, Laboratoire ECOMAR FRE 3560 (CNRS/INEE/UR), France P Frouin --- Université de la Réunion, Laboratoire ECOMAR FRE 3560 (CNRS/INEE/UR), France S Jaquemet --- Université de la Réunion, Laboratoire ECOMAR FRE 3560 (CNRS/INEE/UR), FranceAt Réunion Island (south-western Indian Ocean), artificial reefs were submerged in 2003 in a bay and were soon colonised by fish, among which were the highly abundant commercial species Lutjanus kasmira, Priacanthus hamrur and Selar crumenophthalmus. The high concentration and... -
The importance of estuarine-derived carbon for the nearshore marine environment: studies on two contrasting South African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PD Vorwerk --- Department of Zoology and Entomology, South Africa PW Froneman --- Department of Zoology and Entomology, South AfricaThe food web structure within and adjacent to two permanently open estuaries with contrasting flow regimes along the south-eastern coast of South Africa was investigated employing stable isotope analysis. The Kariega Estuary is considered a freshwater-deprived system, while the Great... -
Nitrogen uptake dynamics of a persistent cyanobacterium Cyanothece sp. bloom in Lake St Lucia, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SJ du Plooy --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa AJ Smit --- School of Life Sciences, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa DG Muir --- Department of Biology, Medgar Evers College, USAWorldwide, persistent cyanobacterial blooms are becoming more frequent and are often associated with effects of global climate change. In June 2009, a widespread bloom of the unicellular cyanobacterium, Cyanothece sp., appeared in North Lake and False Bay of Lake St... -
Stable isotope evidence of food web connectivity by a top predatory fish (Argyrosomus japonicus: Sciaenidae: Teleostei) in the Kowie Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Bergamino --- Department of Zoology and Entomology, South Africa T Dalu --- Department of Zoology and Entomology, South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa L Carassou --- Department of Zoology and Entomology, South Africa NB Richoux --- Department of Zoology and Entomology, South AfricaIn this study, food web connectivity within the Kowie Estuary on the south-east coast of South Africa was evidenced by the trophic behaviour of the predominantly piscivorous Argyrosomus japonicus. We examined stable isotopes of carbon (δ13C) and nitrogen (δ15N) in... -
Trophic investigations of Cape fur seals at the easternmost extreme of their distribution
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Connan --- Department of Zoology, South Africa GJG Hofmeyr --- Department of Zoology, South Africa MJ Smale --- Department of Zoology, South Africa PA Pistorius --- Department of Zoology, South AfricaThe diet of Cape fur seals Arctocephalus pusillus pusillus in the eastern portion of their distribution has received little attention previously, and was studied using traditional methods only. In 2013 we therefore assessed the diet of seals at the easternmost... -
Predation by introduced largemouth bass Micropterus salmoides on indigenous marine fish in the lower Kowie River, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: ML Magoro --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa L Carassou --- Department of Zoology and Entomology, South AfricaThe predatory impact of introduced largemouth bass Micropterus salmoides on the juveniles of estuary-associated indigenous marine fish species in the lower Kowie River and estuary headwaters was investigated in 2012–2013. Stomach contents and stable isotope analyses were employed to assess... -
Towards an isotope ecology of Cape Fynbos small mammals
Item type: Journal Article • Journal: African Zoology • Authors: Irene M. van den Heuvel --- Biozentrum Grindel, Zoological Institute and Museum, University of Hamburg, Martin-Luther-King Platz 3, D-20146 Hamburg, Germany Jeremy J. Midgley --- Department of Botany, South AfricaWe investigated ecological separation through dietary partitioning of small mammals in the nutrient-poor Fynbos biome using a stable isotope approach. Hair samples from eight species of co-occurring small mammals in two separate locations were analysed for stable carbon (13C/12C) and... -
A Porites lutea climate record from Sodwana Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Hayman --- School of Agriculture, Earth and Environmental Sciences, Geological Sciences, South Africa R Uken --- School of Agriculture, Earth and Environmental Sciences, Geological Sciences, South AfricaWe report on a 41-year (winter 1970 to winter 2010) Porites lutea coral core climate record from Two-Mile Reef, Sodwana Bay, in the South-Western Indian Ocean. X-ray analysis, ultraviolet fluorescent photography and stable isotope (δ18O and δ13C) analysis revealed skeletal... -
The status of the Damara Tern in the Eastern Cape, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Philip A Whittington --- East London Museum, South Africa Anthony J Tree --- Department of Zoology, South Africa Maëlle Connan --- Department of Zoology and Entomology, South Africa Elizabeth G Watkins --- , South AfricaThe Eastern Cape population of the Damara Tern Sternula balaenarum was estimated to be 25–29 pairs in the 2008/09 and 2009/10 breeding seasons. The population appears to be stable and has probably increased slightly since the early 1990s. An eastward... -
Incorporating stable isotopes into a multidisciplinary framework to improve data inference and their conservation and management application
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HM Christiansen --- Great Lakes Institute for Environmental Research, Canada AT Fisk --- Great Lakes Institute for Environmental Research, Canada NE Hussey --- Great Lakes Institute for Environmental Research, CanadaThrough its ability to address complex ecological questions and the possibility of analysing large sample sizes to understand population‑level processes, the use of stable isotope analysis (δ13C and δ15N) has grown rapidly in recent years. Importantly, it is now becoming... -
Trophic relationships of hake (Merluccius capensis and M. paradoxus) and sharks (Centrophorus squamosus, Deania calcea and D. profundorum) in the Northern (Namibia) Benguela Current region
Item type: Journal Article • Journal: African Zoology • Authors: Johannes A Iitembu --- Department of Fisheries and Aquatic Sciences, Namibia Nicole B Richoux --- Department of Zoology and Entomology, South AfricaThe trophic relationships of two hake species (Merluccius capensis and M. paradoxus) and three shark species (Centrophorus squamosus, Deania calcea and D. profundorum) were investigated using nitrogen and carbon stable isotope signatures (δ15N and δ13C) of their muscle tissues. The... -
Saldanha Bay, South Africa II: estimating bay productivity
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GC Pitcher --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, South Africa ME Smith --- Marine Remote Sensing Unit, Department of Oceanography, South Africa TA Probyn --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, South AfricaSaldanha Bay is a narrow-mouth bay on the west coast of South Africa linked to the southern Benguela upwelling system. Bay productivity was investigated by use of the conventional light-and-dark bottle oxygen method, and, for comparison, through assimilation of the... -
Riverine dominance of a nearshore marine demersal food web: evidence from stable isotope and C/N ratio analysis
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AM de Lecea --- School of Life Sciences, University of KwaZulu-Natal, South Africa AJ Smit --- School of Life Sciences, University of KwaZulu-Natal, South Africa ST Fennessy --- Oceanographic Research Institute, South AfricaThe Thukela Bank, KwaZulu-Natal, supports a diverse ecosystem and South Africa’s only prawn fishery. Oceanographic studies suggest riverine input is not important for the biology of this system, whereas biological studies suggest the contrary, with prawn catches increasing with increased... -
Stable isotope analysis of consumer food webs indicates ecosystem recovery following prolonged drought in a subtropical estuarine lake
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MS Bird --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa NAF Miranda --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa N Peer --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa JL Raw --- DST/NRF Research Chair in Shallow Water Ecosystems, South AfricaAssessing changes in food-web structure provides a useful monitoring tool for gauging the resilience of ecosystems in the face of climatic impacts. We consider the ecological resilience of a large estuarine lake (St Lucia Estuary, South Africa) in the wake... -
Trophic ecology and persistence of invasive silver carp Hypophthalmichthys molitrix in an oligotrophic South African impoundment
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Lübcker --- Department of Zoology and Entomology, South Africa J Dabrowski --- Department of Zoology and Entomology, South Africa TA Zengeya --- Department of Zoology and Entomology, South Africa PJ Oberholster --- Council for Scientific and Industrial Research (CSIR), South Africa G Hall --- South Africa Stable Isotope Laboratory, South Africa S Woodborne --- South Africa Stable Isotope Laboratory, South Africa MP Robertson --- Centre for Invasion Biology, Department of Zoology and Entomology, South AfricaThe alien invasive silver carp Hypophthalmichthys molitrix established a self-sustaining feral population in an oligotrophic impoundment, Flag Boshielo Dam, in South Africa. The ability of this population to persist in a dam with low algal biomass (median annual suspended chlorophyll... -
Ecology and behaviour of Palm-nut Vultures Gypohierax angolensis in the Bijagós Archipelago, Guinea-Bissau
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Camilo Carneiro --- Department of Biology and CESAM, Portugal Mohamed Henriques --- Faculty of Sciences, Portugal Castro Barbosa --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Quintino Tchantchalam --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Aissa Regalla --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Ana R Patrício --- Centre for Ecology and Conservation, UK Paulo Catry --- MARE – Marine and Environmental Sciences Centre, PortugalPopulations of many vulture species have undergone substantial declines. In Africa, 82% are threatened and although research on vultures has increased, the biology and ecology of several species is still poorly known. The Palm-nut Vulture Gypohierax angolensis has peculiar ecological... -
Determination of water quality, and trace metals in endemic Sarotherodon linellii, Pungu maclareni and Clarias maclareni, in crater Lake Barombi Mbo, Cameroon
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BN Sone --- Faculty of Environmental Sciences and Natural Resource Management, Norway. Current address: c/o P Ndumbe, Standard Chartered Bank, Yaounde, Cameroon BO Rosseland --- Faculty of Environmental Sciences and Natural Resource Management, Norway. Current address: c/o P Ndumbe, Standard Chartered Bank, Yaounde, Cameroon H-C Teien --- Faculty of Environmental Sciences and Natural Resource Management, Norway. Current address: c/o P Ndumbe, Standard Chartered Bank, Yaounde, CameroonConsidering water pollution as a potential threat to some endemic cichlids of Lake Barombi Mbo, Cameroon, an investigation was done in 2011 to determine trace metals in its water, linking their uptake in gills and liver of fish to water... -
Increasing crop diversity increased soil microbial activity, nitrogen-sourcing and crop nitrogen, but not soil microbial diversity
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Zander S Venter --- Department of Animal Sciences, South Africa Samantha L Scott --- Plant Conservation Unit, South Africa Johann Strauss --- Directorate-Plant Sciences, Western Cape Department of Agriculture, South Africa Karin Jacobs --- Department of Microbiology, South Africa Heidi-Jayne Hawkins --- Conservation South Africa, Centre for Biodiversity Conservation, Kirstenbosch National Botanical Gardens, South AfricaThe relationships between crop diversity, soil microbial diversity and agroecosystem functioning are not well understood. Soils under wheat monoculture, wheat–medic, and wheat–medic plus clover rotations from a 19-year-old wheat rotation trial in South Africa were measured for soil microbial functional... -
The bivalve Lembulus bicuspidatus may enhance denitrification in shelf sediment at the Angola–Benguela Frontal Zone
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Neumann --- University of Hamburg, Institute for Geology, Germany A Flohr --- Leibniz Center for Tropical Marine Ecology, GermanyWe collected living individuals of the bivalve Lembulus bicuspidatus, which shows an unusual preference for the oxygen-deficient habitat found at the Angola–Benguela Frontal Zone of the southeastern Atlantic. With a series of incubation experiments with 15N-labelled nitrate as a tracer... -
Dissimilar stem and leaf hydraulic traits suggest varying drought tolerance among co-occurring Eucalyptus grandis × E. urophylla clones
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Casparus J Crous --- Department of Plant and Soil Sciences, South Africa Izette Greyling --- Department of Microbiology and Plant Pathology, South Africa Michael J Wingfield --- Department of Plant and Soil Sciences, South AfricaIn South Africa, there is currently a phenomenon where a Eucalyptus grandis × E. urophylla clone is dying on a large scale, whereas co-occurring clones in the same plantation area remain healthy. No primary biotic pathogen has been isolated from... -
Evidence for diet partitioning among three coexisting native freshwater fishes in South Africa's Cape Fold Ecoregion
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JM Shelton --- Freshwater Research Centre (FRC), South Africa MS Bird --- Department of Zoology, South Africa SM Marr --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaThe partitioning of limited resources commonly explains how different species can coexist within the same ecological community. In this 2010 study, the diets of three coexisting freshwater fishes (Cape galaxias Galaxias zebratus, n = 27; Cape kurper Sandelia capensis, n... -
Wintertime rates of net primary production and nitrate and ammonium uptake in the southern Benguela upwelling system
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RF Flynn --- Department of Oceanography, South Africa JM Burger --- Department of Oceanography, South Africa K Pillay --- Branch: Oceans and Coasts, Department of Environmental Affairs (DEA), South Africa SE Fawcett --- Department of Oceanography, South AfricaThe elevated levels of primary productivity associated with eastern boundary currents are driven by nutrient- rich waters upwelled from depth, such that these regions are typically characterised by high rates of nitrate-fuelled phytoplankton growth. Production studies from the southern Benguela... -
Protected nearshore shallow and deep subtidal rocky reef communities differ in their trophic diversity but not their nutritional condition
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ER Heyns-Veale --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa NB Richoux --- Department of Zoology and Entomology, South Africa ATF Bernard --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa A Götz --- Elwandle Node, South African Environmental Observation Network (SAEON), South AfricaLarge physical changes that alter reef macrobenthos and fish assemblages occur with increasing depth, so the biological processes that regulate communities at different depths are expected to diverge. We used analyses of stable isotopes (δ13C and δ15N) and fatty acids... -
Comparative trophic ecology of Cape anchovy Engraulis encrasicolus and Natal anchovy Stolephorus holodon off South Africa’s east coast
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Horton --- Department of Biological Sciences, South Africa CD van der Lingen --- Department of Biological Sciences, South AfricaThe distributional ranges of Cape anchovy Engraulis encrasicolus and Natal anchovy Stolephorus holodon presently overlap at their eastern and western extremes, respectively, off South Africa’s east coast. These species might become more strongly sympatric as a consequence of changed distributions... -
Roseate Terns Sterna dougallii on the southeast coast of South Africa: information on moult and migratory status
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Anthony J Tree --- Port Alfred, South Africa Maëlle Connan --- Department of Zoology, Marine Apex Predator Research Unit, Institute for Coastal and Marine Research, South Africa Philip A Whittington --- Department of Zoology, South AfricaDetermining the migratory status of seabird populations is crucial for addressing conservation concerns. The Roseate Tern Sterna dougallii is considered endangered in South Africa in view of its small breeding population and the threats to eggs and chicks. Earlier works... -
The diet of spotted-necked otters foraging in trout-stocked waters in Mpumalanga, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Rowan K Jordaan --- , South Africa Michael J Somers --- , South Africa Grant Hall --- , South Africa Trevor McIntyre --- , South AfricaHuman-wildlife conflict is likely to increase as urbanisation increases. African clawless otters, Aonyx capensis, and spotted-necked otters, Hydrictis maculicollis, are illegally persecuted for their perceived role in reducing trout in artificially stocked habitats in South Africa. The diet of African... -
Spatial and ontogenetic variability in the diet and trophic ecology of two co-occurring catsharks (Scyliorhinidae) off South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GM van der Heever --- , South Africa CD van der Lingen --- , South Africa RW Leslie --- , South Africa MJ Gibbons --- , South AfricaThe Izak catshark Holohalaelurus regani and the yellow-spotted catshark Scyliorhinus capensis both occur over the continental shelf around South Africa and are often caught together as bycatch in demersal trawls. Yet our understanding of their diet is fragmented, which makes... -
Links between introduced fish and zooplanktonic and zoobenthic food sources in the food webs of two reservoirs of a semi-arid zone in Algeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Djezzar --- , Algeria JM Mortillaro --- , Madagascar SE Doumandji --- , Algeria T Meziane --- , FranceFew studies have focused on the trophic functioning of the reservoirs in Algeria. The study of the gut contents of fish species, as well as the analysis of the stable isotopes of 13C and 15N in the environment, were carried... -
Water uptake plasticity of savanna trees in encroached grassland: small trees match the mature trees
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Séraphine Grellier --- , France Jean-Louis Janeau --- , France Patricia Richard --- , France Nicolas Florsch --- , France David Ward --- , United States Thierry Bariac --- , France Simon Lorentz --- , South AfricaProcesses linked to woody plant encroachment in grassland are still not well understood, especially the interactions between trees and soil water availability. Our aim was to study the depth of water uptake by trees in grassland and its controlling factors... -
Partitioning the sources of sediment organic carbon in South African seagrass meadows
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Bossert --- Stellenbosch University, South Africa S von der Heyden --- Stellenbosch University, South Africa J Colling --- Stellenbosch University, South Africa A Ndhlovu --- Stellenbosch University, South AfricaIn the sediments of seagrass meadows, allochthonous carbon sources can account for 50–90% of sediment organic carbon (SOC), in which non-seagrass carbon is derived from external organic matter advected into the meadow’s sediments or trapped by the seagrass canopy. Identifying... -
Managing drought stress in wheat (Triticum aestivum L.) production: strategies and impacts
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Maltase Mutanda --- University of South Africa, South Africa Hussein Shimelis --- School of Agricultural, South Africa Vincent Chaplot --- School of Agricultural, South Africa Sandiswa Figlan --- University of South Africa, South AfricaDrought stress is a major constraint to sustainable wheat production worldwide, including sub-Saharan Africa, where environmental and poor agronomic practices exacerbate the yield gap. Drought disrupts physiological, biochemical, and molescular processes, negatively impacting crop growth, grain yield and quality. This... -
Intrapopulation isotopic niche structure in mammalian carnivores and herbivores across contrasting habitats
Item type: Journal Article • Journal: African Zoology • Authors: Chanel Lewis --- University of the Free State, South Africa Runè van der Merwe --- University of the Free State, South Africa Chabi AMS Djagoun --- University of Abomey-Calavi, Benin Etotépé A Sogbohossou --- University of Abomey-Calavi, Benin Daryl Codron --- University of the Free State, South AfricaNatural communities exhibit ecological gradients that result in a variety of competitive interactions and variations in niche patterns. Changes in resource availability affect the size of a species’ niche: it expands when a variety of resources are abundant and contracts...