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Phytomass and ecological significance of Chrysocoma ciliata L. within the Lets’eng-la-Letsie catchment area of Lesotho, southern Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2021-01-20 GN Smit; G Janse van Rensburg
The Lets’eng-la-Letsie wetland is an official Ramsar site, but the wetland and upland catchment areas suffer from overgrazing, erosion and over exploitation. Chrysocoma ciliata has a reputation as an unpalatable invader and is particularly common on the drier northern slopes. The objectives of the study were to quantify the phytomass of this shrub with the aid of a developed allometric phytomass quantification
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Changes in vegetation structure, aboveground biomass and soil quality in response to traditional grazing land management practices in the central highlands of Ethiopia African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-12-14 Teklu Wegi; Abubeker Hassen; Melkamu Bezabih; Adugna Tolera
Despite shrinking pastureland in the central highlands of Ethiopia, as a result of cropping, there has been little detailed work to evaluate effects of traditional grazing land management practices on vegetation and soil attributes. This study aimed to quantify vegetation structure, aboveground biomass yield and soil quality, as a result of the impact of enclosure and open access management practices
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Field Guide to Renosterveld of the Overberg African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-12-10 Christopher Whitehouse
(2020). Field Guide to Renosterveld of the Overberg. African Journal of Range & Forage Science. Ahead of Print.
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Topo-edaphic environment and forest plantation disturbance explain patterns of grassland species richness, composition and structure in an agro-ecological landscape, Maputaland, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-12-08 AP Starke; TG O’Connor; CS Everson
Grasslands of the Maputaland coastal plain are biologically diverse and provide a variety of ecosystems services. Yet grasslands in this region are vulnerable to continuing development by plantation forestry that provides economic benefits to local communities. In order to provide a framework for land use that maintains grassland heterogeneity in complex agro-ecological systems, this paper characterises
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Topo-edaphic environment and forestry plantation disturbance affect the distribution of grassland forage and non-forage resources, Maputaland, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-12-08 AP Starke; TG O’Connor; CS Everson
Grasslands are integral to rural livelihoods in southern Africa, because they provide hydrological regulation services and a variety of plant resources, including livestock fodder, medicines, and food products. To ensure ongoing provision of these resources in rapidly developing rural landscapes, an understanding of the relationships between grassland species composition and ecosystem services is required
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Water uptake plasticity of savanna trees in encroached grassland: small trees match the mature trees African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-12-01 Séraphine Grellier; Jean-Louis Janeau; Patricia Richard; Nicolas Florsch; David Ward; Thierry Bariac; Simon Lorentz
Processes 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. We studied water uptake in Vachellia sieberiana trees (hereafter called ‘acacias’) in a humid grassland of South Africa. We especially studied
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How stable is the tuft structure of a mesic Drakensberg grassland under various burning regimes? African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-11-18 Terry M Everson; Colin S Everson; Craig D Morris
Management options to maintain the stability of Drakensberg grasslands need to incorporate their dynamic nature in response to fire. This study addressed the lack of information on the spatial and temporal changes of these grasslands at a small (tuft) scale. The basal area of every tuft in three 0.25 m2 quadrats per replicate (3) of four burning treatments was mapped over two years in a long-term burning
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Frequent burning maintained a stable grassland over four decades in the Drakensberg, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-11-18 Craig D Morris; Colin S Everson; Terry M Everson; Paul J Gordijn
The mesic montane grasslands of the uKhahlamba-Drakensberg, which produce cured flammable fuel, have evolved under and are sustained by recurrent fires. The Brotherton burning trial (12 replicated treatments) was established at Cathedral Peak (1 890 m asl) in 1980 to understand how burn season and frequency control the composition and diversity of the montane catchment grassland. Multivariate methods
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Disease surveillance and farmers’ knowledge of Brachiaria (Syn. Urochloa) grass diseases in Rwanda African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-10-13 Bellancile Uzayisenga; Mupenzi Mutimura; James W Muthomi; Agnes W Mwang’ombe; Sita R Ghimire
Brachiaria (syn. Urochloa) is one of the most important tropical forages grass of African origin. Its performance is affected by different constraints, including diseases. This study assessed the distribution, incidence and severity of Brachiaria diseases and documented farmers’ knowledge on Brachiaria diseases in Rwanda. Surveys were conducted in five districts in the dry and wet seasons of 2018 and
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Quantifying grass productivity using remotely sensed data: an assessment of grassland restoration benefits African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-08-21 Thulile Vundla; Onisimo Mutanga; Mbulisi Sibanda
This study sought to evaluate the utility of remotely sensed data in estimating the impact of wattle invasion and clearance on native grass species productivity using Sentinel-2 multispectral instrument (MSI) imaging and the partial least squares regression (PLSR) algorithm. Therefore this study assessed grass above ground biomass (AGB) at various levels of wattle invasion In assessing the impacts
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Characterisation of ecosystem-based adaptations to drought in the central cattle corridor of Uganda African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-08-07 Susan Nanfuka; David Mfitumukiza; Anthony Egeru
Ecosystems provide climate-change adaptation opportunities including ecosystem services, adaptation benefits and livelihood improvement especially for natural resource dependent communities. To contribute to the understanding of location specific adaptation processes of predominantly agro-pastoralists, a study was carried out in the central cattle corridor of Uganda to characterise ecosystem-based
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Feeding and spatial behaviours of transhumant cattle in southern Benin: implications for the sustainable management of rangelands African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-09-03 Rodrigue V Cao Diogo; Josias Steve Adjassin; Luc Hippolyte Dossa; Ibrahim Alkoiret Traoré
Feed intake on pastures plays a vital role in cattle rearing in West Africa. However, the scarcity of pastures during the dry season may result in changing grazing behaviour by cattle. Therefore, we studied the management practices of transhumant herders on communal rangelands through monitoring of cattle herds’ behaviour in southern Benin. We expected changes in grazing behaviours of cattle and shifts
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Interactive effects of prescribed fire and livestock grazing on Seriphium plumosum in South African sour bushveld African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-08-07 Michele D Clark; Carissa L Wonkka; Urs P Kreuter; William E Rogers
Documented increases in woody plant abundance worldwide can reduce land value and grazing capacity. Throughout many grasslands and savannas in South Africa, Seriphium plumosum, an encroaching woody plant, has been rapidly displacing desirable native species. Cost-effective management techniques are required, in order to prevent encroachment. However, the effects of fire and grazing on S. plumosum are
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Analysis of main factors affecting silage fermentation of sorghum prepared with whole crop and stover in semiarid West Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-09-10 Yimin Cai; Zhumei Du; Delma B Jethro; Man Nignan; Seishi Yamasaki
Sorghum (Sorghum bicolor L.) is widely cultivated in semiarid West Africa as a combined crop for human consumption and animal feed. In order to address the shortage of ruminant feed in Burkina Faso, we studied the potential of preparing silage from sorghum at various growth stages and analysed the main factors affecting silage fermentation, including the microbial population, chemical composition and
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Conservation Biology in Sub-Saharan Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-09-10 Adrian M Shrader
(2020). Conservation Biology in Sub-Saharan Africa. African Journal of Range & Forage Science. Ahead of Print.
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Potentials of leys or pasture-based forage production in Nigeria African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-08-25 Saheed Olaide Jimoh; Yunusa Muhammad Ishiaku; Tracy Burnett; Ahmed Adeyemi Amisu; Rasheed Adekunle Adebayo
Fulani pastoralists are widely distributed across the six geographical zones of Nigeria and migrate from north to south in search of natural grazing lands at times of forage scarcity. This migration leads annually to resource use conflict and deadly attacks between migrating pastoralists and sedentary arable farmers. These conflicts have generated heated scholarly debates over the last few decades
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Land reform and its impact on the arid South African environment: Riemvasmaak as a case study African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-08-11 GS Fleury; MT Hoffman; SW Todd
The 75 000 ha, hyper-arid area of Riemvasmaak represents one of the first land restitution cases in post-apartheid South Africa. People who were forcibly removed in 1974 were resettled in 1995. We describe the impact that people and domestic livestock have had on the vegetation of Riemvasmaak since resettlement. Matched photographs and botanical surveys undertaken at 10-year intervals (1995, 2005 and
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Is a long hygroscopic awn an advantage for Themeda triandra in drier areas? African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-08-06 Craig D Morris
Themeda triandra has bigeniculate hygroscopic lemma seed awns that twist when wet and drying, thereby transporting the caryopsis across the soil surface into suitable germination microsites. The prediction that awns would be longer in drier grassland and have greater motility to enable them to move quickly and farther to find scarce germination sites was tested in KwaZulu-Natal. Awns (n = 100) were
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Does defoliation frequency and severity influence plant productivity? The role of grazing management and soil nutrients African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-07-21 Zander S Venter; Heidi-Jayne Hawkins; Michael D Cramer
Rangeland management approaches, including rotational grazing, rely on assumptions about plant growth responses to the intensity, or severity (sward height) plus frequency, of defoliation. We tested these assumptions at the farm, patch and plant scale using data from a grazing management trial in an Eastern Cape mesic grassland of South Africa along with field plot and glasshouse pot experiments. The
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What grass characteristics drive large herbivore feeding patch selection? A case study from a South African grassland protected area African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-07-22 Elena Mariotti; Francesca Parrini; Cornelius J Louw; Jason P Marshal
The coexistence of a large herbivore community depends on the degree of overlap in the resource used by the different species composing it. We investigated the role of grass greenness, height, biomass and feeding patch status on feeding patch selection by ruminant black and blue wildebeest (Connochaetes gnou, Connochaetes taurinus), red hartebeest (Alcelaphus buselaphus) and non-ruminant plains zebra
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Patch-scale selection patterns of grazing herbivores in the central basalt plains of Kruger National Park African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-29 Cyanne Young; Hervé Fritz; Erica AH Smithwick; Jan A Venter
Large herbivores form an essential component in the ecosystem, because of the impact that they have on their surrounding habitat. In this study, we aimed to evaluate some of the mechanisms behind how herbivores select forage at a patch scale. Thirty-six experimental plots were established and fitted with camera traps in Kruger National Park to test forage selectivity by grazers. Plots were manipulated
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The beneficial effects of growth regulators on forage yield and quality of Amaranthus caudatus under different water stress conditions African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-10 Somayeh Farshbaf-Jafari; Alireza Pirzad; Mehdi Tajbakhsh; Kazem Ghassemi-Golezani
In order to improve crop productivity, farmers should have strategies for higher quantity and quality of forage without excessive inputs, like irrigation water. In order to assess forage quality of Amaranthus caudatus in response to irrigation levels (irrigation after 70, 140 and 210 mm of evaporation from class A pan) as main plots and foliar sprays of abscisic acid (ABA; 50 μM), salicylic acid (SA;
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A comparative assessment of the contribution of two different models for clearing invasive alien plants using grazing regimes in the Eastern Cape, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-26 T Morokong; JN Blignaut
Invasive alien plants (IAPs) compromise the productive capability of a land parcel from both an economic and a biodiversity perspective. Given the magnitude of degradation and the benefits of landscape-scale restoration, a unified approach among stakeholders is required to upscale restoration efforts. Seeking such an approach, we compare the efficiencies of two restoration and land use models for the
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Relationships between farmer perceptions and temporal variation in nutritive value of browse species on savanna rangelands African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-07-20 Clarice P Mudzengi; Amon Murwira; Tinyiko Halimani; Herve Fritz; Chrispen Murungweni
In livestock-based livelihoods of the developing world, determination of the nutritive value of browse species is mainly associated with farmer perceptions. Additionally, little is known on seasonal variation in nutritive value of these species in some areas. Therefore, chemical analysis is necessary to validate farmer nutritive value ranking, because this has implications on rangeland management.
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Livestock predation and its management in South Africa: A scientific assessment African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-05-20 Lisa Hebbelmann
(2020). Livestock predation and its management in South Africa: A scientific assessment. African Journal of Range & Forage Science: Vol. 37, No. 3, pp. 243-244.
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Aboveground-Belowground Community Ecology African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-05 Heidi-Jayne Hawkins
(2020). Aboveground-Belowground Community Ecology. African Journal of Range & Forage Science: Vol. 37, No. 3, pp. 245-246.
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Revegetation of marginal saline rangelands of southern Tunisia using pastoral halophytes African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-09 Abderrazak Tlili; Emna Ghanmi; Naziha Ayeb; Mounir Louhaichi; Mohamed Neffati; Mohamed Tarhouni
Revegetation of marginalised rangelands using pastoral halophytes is considered an appropriate scientific and environmental approach to rehabilitation. Atriplex halimus L. (Amaranthaceae), A. mollis Desf. (Amaranthaceae), Cenchrus ciliaris L. (Poaceae) and Lotus creticus L. (Fabaceae) are promising species for arid rangeland rehabilitation, because of their adaptation and palatability. Dry biomass
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The Ecology of Browsing and Grazing II African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-09 Peter F Scogings
(2020). The Ecology of Browsing and Grazing II. African Journal of Range & Forage Science: Vol. 37, No. 2, pp. 197-198.
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Aboveground-Belowground Community Ecology African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-06-05 Heidi-Jayne Hawkins
(2020). Aboveground-Belowground Community Ecology. African Journal of Range & Forage Science. Ahead of Print.
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Mapping key browse resources in a heterogeneous agricultural landscape African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-05-22 Clarice P Mudzengi; Amon Murwira; Fadzai M Zengeya; Tinyiko Halimani; Herve Fritz; Chrispen Murungweni
We investigated application of MaxEnt, a one-class classifier, in mapping the spatial distribution of Colophospermum mopane, Dichrostachys cinerea and Salvadora persica using drainage, elevation, slope, soil and Normalised Difference Vegetation Index as environmental variables. Model performance was evaluated based on the area under the ROC curve (AUC), Kappa and Total Skills Statistic. The AUC results
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The value of rested sourveld in a communal grazing area in the Eastern Cape, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-05-12 Lynton J Dedekind; Jon McCosh; Terry M Everson; Craig D Morris; Dayle Trotter
The potential for forage accumulated during periodic long rests to provide valuable winter grazing for livestock in heavily stocked communal rangelands in sourveld was assessed. In a continuously-grazed commonage at Ntshiqo in the Eastern Cape, South Africa, we measured seasonal patterns of biomass accumulation and forage quality under a short season rest (October–January), a full summer rest (October–June)
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Seasonal changes of copper and zinc concentrations in browse saltbush (Atriplex canescens (Pursh) Nutt.) from the Algerian arid rangelands African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-05-12 Bouzid Nedjimi
The study aimed to elucidating the seasonal variations of copper (Cu2+) and zinc (Zn2+) contents occurring in Atriplex canescens shrubs, as well as in surrounding soil. Cu and Zn concentrations were determined using X-ray fluorescence (XRF) spectrometry. Data were compared with those reported in other Atriplex species from different regions of the world. The results disclosed that the highest plant
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Long-term influence of season of grazing and rainfall on vegetation in the eastern Karoo, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-05-12 Justin CO du Toit; Timothy G O’Connor
In the Nama-Karoo, South Africa, rainfall and grazing by livestock are two important drivers of botanical composition. Summer rains are advantageous particularly to the grass layer, whereas the characteristic dwarf shrubs survive better than grasses during drought, and benefit from rainfall during cool months. Heavy grazing by livestock during summer reduces the abundance of grasses, whereas winter
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Methods of storing cactus pear genotypes for animal feeding African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-05-06 Chrislanne Barreira de Macêdo Carvalho; Ricardo Loiola Edvan; Keuven dos Santos Nascimento; Romilda Rodrigues do Nascimento; Leilson Rocha Bezerra; Darkle Luiza de Souza Jácome; Viviany Lúcia Fernandes dos Santos; Hermógenes Almeida de Santana Júnior
The objective of this study was to evaluate storage methods of cactus pear as a way of conservation for use in animal feeding. The randomised experimental design composed twelve treatments and three replications. Three cactus pear genotypes, Nopalea cochenillifera genotype Doce and Baiana and Opuntia tuna genotype Orelha de Elefante Mexicana (OEM), were stored in natura (0, 30 and 60 days after harvest)
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Context and complexity: response to Fabricius review of ‘Complex Ecology’ African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-04-30 Charles G Curtin
(2020). Context and complexity: response to Fabricius review of ‘Complex Ecology’. African Journal of Range & Forage Science: Vol. 37, No. 2, pp. 141-142.
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Desertification: Past, Current and Future Trends African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 M Timm Hoffman
(2020). Desertification: Past, Current and Future Trends. African Journal of Range & Forage Science: Vol. 37, Droughts in South African savannas, pp. 139-140.
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Drought: An Interdisciplinary Perspective African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Jennifer M Fitchett
(2020). Drought: An Interdisciplinary Perspective. African Journal of Range & Forage Science: Vol. 37, Droughts in South African savannas, pp. 137-138.
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Observations on the natural history of a savanna drought African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Izak PJ Smit; William J Bond
Drought studies are often opportunistic and post hoc, where a drought fortuitously occurs during a research project that was not specifically designed to study the drought, but where researchers capitalised on the opportunity. These studies often lack focus on formulating and studying ‘drought specific’ research questions. By learning from observations during droughts, research gaps can be identified
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Drought challenges for nature tourism in the Sabi Sands Game Reserve in the eastern region of South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Tamzyn Smith; Jennifer M Fitchett
The Lowveld of South Africa, a savanna biome region economically dominated by nature tourism, has experienced a prolonged dry period beginning in approximately 2015. Despite emerging literature on climate and tourism in southern Africa, the challenges to tourism in the region as a result of the drought remain under explored. This paper quantifies the extent of the reduction in precipitation during
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Effect of drought on communal livestock farmers in KwaZulu-Natal, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 S Vetter; VL Goodall; R Alcock
Despite the size of the informal small-scale farming sector and its livestock holdings in South Africa, there has been little detailed work to assess how livestock populations are affected by drought. South Africa experienced a major drought in 2015–2016. We analysed goat and cattle census data from the Msinga area in KwaZulu-Natal, which represent the livestock of some 3 000 households. Cattle farmers
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Drought amnesia: lessons from protected areas in the eastern Lowveld of South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Mike JS Peel; Izak P Smit
Protected areas (PAs) adjacent to the Kruger National Park (KNP) are divided into fenced and unfenced properties. We discuss land-use development to provide context of how these savannas have evolved over the past century. Although the PAs have embraced the basic philosophies of the KNP management approach and have similar high-level objectives, they function at different spatial, and consequently
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Megaherbivore response to droughts under different management regimes: lessons from a large African savanna African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Izak PJ Smit; Mike JS Peel; Sam M Ferreira; Cathy Greaver; Danie J Pienaar
Droughts are predicted to increase in frequency and intensity for large parts of Africa. It is unclear how this may impact native grazers in protected areas, and how these outcomes may differ under contrasting management approaches. Reducing artificial water sources and increasing the size of protected areas have been proposed as management responses that could possibly increase system resilience and
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Forb community responses to an extensive drought in two contrasting land-use types of a semi-arid Lowveld savanna African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 F Siebert; J Klem; H Van Coller
Projected increases in the frequency and severity of drought events are expected to impose changes in the ecology of native forb communities in semi-arid ecosystems. We examined the state of forb communities during, and directly after an extreme drought event across two contrasting land-use types, which included a protected area (high diversity of free roaming wild herbivores) and communal rangeland
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Grass community responses to drought in an African savanna African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 C Wigley-Coetsee; AC Staver
Drought is often discussed as a major perturbation in savanna ecosystems, associated with lasting shifts in savanna structure and functioning. However, historically, droughts have occurred frequently in southern African savannas, suggesting that plants might benefit from being resilient to drought. Here, we evaluate whether the 2014–2016 drought was an extreme event in terms of effects on the herbaceous
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Locally high, but regionally low: the impact of the 2014–2016 drought on the trees of semi-arid savannas, South Africa African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 AM Swemmer
Drought is thought to be a factor limiting the abundance of shrubs and trees in savannas, but this has rarely been tested empirically. The severe drought of 2014–2016 provided an opportunity to document the impact of drought on the mortality of woody plants in semi-arid savannas of South Africa. Annual data from long-term tree monitoring plots were combined with opportunistic sampling in areas of high
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Could drought constrain woody encroachers in savannas? African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Madelon F Case; Benjamin J Wigley; Corli Wigley-Coetsee; A Carla Staver
Droughts are expected to become more frequent and severe, due to climate change, with uncertain consequences for savanna vegetation. Drought-driven tree mortality has been observed in some savannas, but little is known about how tolerant savanna trees are to drought, or what determines differences among species in drought vulnerability. Here, we examine which characteristics best distinguished tree
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Recent droughts in the Kruger National Park as reflected in the extreme climate index African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 Johan Malherbe; Izak PJ Smit; Konrad J Wessels; Philip J Beukes
Associated with the 2015/2016 El Niño, extreme drought occurred over the Lowveld of South Africa. The area includes the Kruger National Park (KNP). Significant die-offs of a mega herbivore species occurred, corroborated by census data in KNP. The drought situation and impact were likely exacerbated by a frequency of recorded extreme temperatures never observed before together with increased numbers
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Special Issue: Drought in South African savannas African J. Range Forage Sci. (IF 1.31) Pub Date : 2020-03-24 William Bond; Justin du Toit; Johan Malherbe
(2020). Special Issue: Drought in South African savannas. African Journal of Range & Forage Science: Vol. 37, Droughts in South African savannas, pp. iii-v.