Browsing by Author "Samuels, Igshaan"

Now showing 1 - 5 of 5
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    Does the landscape functionality approach provide insight into rangeland conditions in the Tanqua Karoo region, South Africa?
    (PeerJ, 2022) Saaed, Manam; Jacobs, Shayne; Samuels, Igshaan
    The harsh environmental conditions coupled with a long history of overgrazing have altered the ecology of the arid Tanqua Karoo rangelands in South Africa, which necessitates rehabilitation. However, a suitable method for monitoring rangeland function over time is required for sustainable management. In this study, vegetation characteristics and landscape function indices were used to rate and compare rangeland conditions in 43 sites distributed among three vegetation types: Tanqua Karoo, Tanqua Wash Riviere, and Tanqua Escarpment Shrubland, which occupy different landscapes in the Tankwa Karoo National Park. The results showed low values of vegetation volume (mean of 10.1 m3 per 100 m−2 ) and low vegetated patches (mean of 29% patches vs 71% fetches). The overall landscape function indices (soil stability, water infiltration, and nutrient recycling) were low and amounted to 55%, 28%, and 17%, respectively.
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    Investigating the diet selection and genetic variation of small ruminants in a dryland pastoral system in South Africa
    (University of the Western Cape, 2019) Schroeder, Amy; Engelbrecht, Adriaan; Samuels, Igshaan; Cupido, Clement
    Small ruminants found in pastoral dryland systems face many challenges regarding constant environmental and climate changes. These variable environments are home to many pastoralists who use the natural resources to sustain their livestock. Due to the prevailing environmental changes, these pastoralists require various adaptation strategies for the survival of their small ruminants. Adaptation is vital for all pastoralists globally, especially those living in semi-arid to arid regions as these areas are badly impacted by climate change. Farming with small ruminants that are able to constantly adapt to variable environments are a long-term and low cost resource strategy for farmers in these areas. Drought is a recurring challenge that farmers in dryland systems have to cope with and small ruminants are forced to adapt to food and water available to them as drought affects their survival, reproduction and production. This is because drought affects the environment directly as rainfall has an impact on all forage and water resources found in drylands. Thus available forage and the utilisation of this resource by small ruminants is essential for sheep and goat farmers who depend on these animals for their livelihoods. This thesis sets out to establish sheep and goat breeds found in a dryland pastoral system in South Africa focussing on their genetic differences and their diet selection during a drought period. The study was carried out in the 582 634 ha Steinkopf communal area located in the semi-arid to arid region of Namaqualand in South Africa. The dominant land use in this area is livestock farming where farmers utilise two biomes for grazing. Using mitochondrial DNA, genetic differences were investigated in small ruminants found in Steinkopf. The small ruminants that were studied were the Boer goats, Swakara sheep (Karakul) and cross-bred sheep. These were the most commonly farmed small ruminants in this area. Genetic differences and diversity found within the small ruminants in this area supports their ability to adapt to drought and changing environments. Diet selection of these small ruminants were assessed using direct forage observation during this drought period in both the Succulent and Nama Karoo biomes. Findings of the study indicate that small ruminants during a drought period will largely forage on what is available to them. Boer goats changed their diets from browser to grazers in the different biomes while sheep remained grazers in both biomes. This suggests that these animals are well adapted to changing forage availability and will adjust their feeding behaviours accordingly. Succulent plant species were utilised by all small ruminants and this can be regarded as new knowledge for small ruminants in dryland systems. Succulent species play a role in the diets of small ruminants in the Steinkopf rangeland and these animals have adapted traits that allow them to eat plants that contain high levels of phenolics and tannins, which show their high adaptability to this area. This study also revealed that indigenous and locally bred sheep in this area are crucial resources for livestock farming in this area. Swakara sheep in this area showed a low level of genetic variation while cross-bred sheep and the Boer goat had significant variation. With a long tradition of breeding small ruminants in the Steinkopf communal area that suit changing conditions, livestock keepers have accumulated detailed knowledge of their animals. Recommendations from this study were to do further studies regarding genetic variation within the cross-bred sheep as this information will be useful for breeding programs in dryland areas and it will add to the small ruminant genetics in South Africa. Because this study was conducted in a drought period, I recommend that diet selection should be observed during a regular wet and dry period as this would indicate how these animals adapt to what forage is available to them. These studies can act as management strategies for herders as it can provide information on how to use the natural resources sustainably.
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    Nitrogen fertilization increases the growth and nutritional quality of the forage legume, Calobota sericea – A preliminary investigation
    (Elsevier, 2023) Britz, Ethan; Cyster, Lilburne; Samuels, Igshaan
    Calobota sericea is being evaluated as a forage for drought stressed areas. The nutritional quality of C. sericea from native populations are poor, and this is believed to be due to poor soil fertility. Therefore, a greenhouse trial was established to determine the impact of N-fertilization level (0, 25, 50, 75 and 100 kg/ha) on the growth and nutritional quality of C. sericea plants. Three-monthold plants were harvested and the root and shoot length, as well as branching intensity on each plant determined. Thereafter, the shoots were separated into leaves and stems and all plant parts were oven dried for dry mass determination. After weighing, the leaves and stems for each plant were combined and the dried shoots used for nutrient determination. Results indicated that increased N application levels is positively correlated with improved C. sericea growth. Similarly, mineral nutrient uptake increased significantly under all the N-fertilization treatments and crude protein content increased from 9.6% to 18.6%. Plant growth was only statistically significantly (p < 0.05) improved when N was applied at rates of 50 kg/ha and more, but crude protein content increased from the lowest N application rates (25 kg/ha). The improved growth and nutrient uptake could primarily be explained by improved resource allocation under N-fertilization. Therefore, appropriately fertilized C. sericea can result in improved forage production and improved quality forages and when N is applied at high enough rates.
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    Nitrogen fertilization increases the growth and nutritional quality of the forage legume, calobota sericea – A preliminary investigation
    (Heliyon, 2023) Britz, Ethan; Cyster, Lilburne; Samuels, Igshaan; Clement, Cupido
    Calobota sericea is being evaluated as a forage for drought stressed areas. The nutritional quality of C. sericea from native populations are poor, and this is believed to be due to poor soil fertility. Therefore, a greenhouse trial was established to determine the impact of N-fertilization level (0, 25, 50, 75 and 100 kg/ha) on the growth and nutritional quality of C. sericea plants. Three-month-old plants were harvested and the root and shoot length, as well as branching intensity on each plant determined. Thereafter, the shoots were separated into leaves and stems and all plant parts were oven dried for dry mass determination. After weighing, the leaves and stems for each plant were combined and the dried shoots used for nutrient determination.
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    Transhumance pastoralism in West Africa – its importance, policies and challenges
    (African Journal of Range & Forage Science, 2023) Samuels, Igshaan; Timpong-Jones, Eric Cofie; Sarkwa, Felix Owusu
    The Economic Community of West African States (ECOWAS) recognises transhumance pastoralism as a beneficial livestock production system that can contribute to food security together with economic and political stability. Thus, the subregional bloc put together the ECOWAS Protocol on Transhumance and supporting regulations to actualise these benefits. These policies seek to regulate transhumance pastoralism by ensuring that herd movements are along defined migratory corridors among member states. This review assesses the importance of transhumance pastoralism in West Africa, local and cross-border policies, and associated challenges, with emphasis on herder–farmer conflicts. It was realised that the movement of large numbers of livestock into rangelands (1) provides employment for many, and thus improves livelihoods; (2) improves productivity through high milk production and high fertility; (3) reduces moribund and combustible forage materials in the dry season; and (4) enhances seed dispersal, soil fertility and plant diversity on rangelands. This review shows that the ECOWAS cross-border transhumance protocols have led to infrastructural developments in some member states, but the partial enforcement of protocols has led to herder–farmer conflicts. We conclude that transhumance pastoralism and the regulatory policies have several benefits. However, to ensure policy compliance and avoid herder–farmer conflicts, the policies need to be reviewed and discernible gaps eliminated.