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1.
Catena (Amst) ; 243: 108216, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39021895

RESUMEN

The preservation and augmentation of soil organic carbon (SOC) stocks is critical to designing climate change mitigation strategies and alleviating global warming. However, due to the susceptibility of SOC stocks to environmental and topo-climatic variability and changes, it is essential to obtain a comprehensive understanding of the state of current SOC stocks both spatially and vertically. Consequently, to effectively assess SOC storage and sequestration capacity, precise evaluations at multiple soil depths are required. Hence, this study implemented an advanced Deep Neural Network (DNN) model incorporating Sentinel-1 Synthetic Aperture Radar (SAR) data, topo-climatic features, and soil physical properties to predict SOC stocks at multiple depths (0-30cm, 30-60cm, 60-100cm, and 100-200cm) across diverse land-use categories in the KwaZulu-Natal province, South Africa. There was a general decline in the accuracy of the DNN model's prediction with increasing soil depth, with the root mean square error (RMSE) ranging from 8.34 t/h to 11.97 t/h for the four depths. These findings imply that the link between environmental covariates and SOC stocks weakens with soil depth. Additionally, distinct factors driving SOC stocks were discovered in both topsoil and deep-soil, with vegetation having the strongest effect in topsoil, and topo-climate factors and soil physical properties becoming more important as depth increases. This underscores the importance of incorporating depth-related soil properties in SOC modelling. Grasslands had the largest SOC stocks, while commercial forests have the highest SOC sequestration rates per unit area. This study offers valuable insights to policymakers and provides a basis for devising regional management strategies that can be used to effectively mitigate climate change.

2.
Nutrients ; 16(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38999816

RESUMEN

Dietary diversity is one of the fundamental factors of nutritional security and a proxy used to measure diet quality. The objective of this study was to investigate the relationship between village chicken availability and the dietary diversity of households along a rural-urban gradient. Face-to-face interviews were conducted using a structured questionnaire in rural (n = 100), peri-urban (n = 100), and urban (n = 100) areas of Pietermaritzburg uMgungundlovu District, KwaZulu-Natal, in South Africa. A positive relationship between distance from the city center and village chicken flock sizes (p < 0.001) was observed. Consumption of vegetables increased with an increase in distance from the city center (p < 0.01). A quadratic relationship was observed between distance from the city center and consumption of livestock-derived foods (LDFs) (p < 0.05). Consumption of LDFs increased with an increase in village chicken flock sizes (p < 0.05). Consumption of vegetables increased with an increase in village chicken flock sizes (p < 0.01). Food variety score (FVS) increased with an increase in distance from the city center (p < 0.05). Assessing the availability of village chickens across rural-urban gradients is a worthy opportunity to utilize to improve households' dietary diversity and alleviate poverty. It can be concluded that expanding village flock sizes could enhance the dietary diversity of households.


Asunto(s)
Pollos , Dieta , Población Rural , Población Urbana , Animales , Sudáfrica , Población Rural/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Humanos , Dieta/estadística & datos numéricos , Verduras , Abastecimiento de Alimentos/estadística & datos numéricos , Femenino , Masculino , Composición Familiar , Adulto , Encuestas y Cuestionarios
3.
Front Sustain Food Syst ; 8: 1392647, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-39006981

RESUMEN

Introduction: Access to credit and information and communication technology (ICT) plays a pivotal role in enhancing the practices of small-scale sugarcane farmers, impacting their financial, social, and economic wellbeing. However, many small-scale farmers need help accessing these resources, thereby affecting their ability to generate sustainable income. This study aimed to assess the factors influencing the adoption of ICT and access to credit and their subsequent impact on small-scale farmers' income. Methods: Employing a multistage sampling technique, 300 small-scale farmers were selected as participants in the study. The recursive bivariate probit regression model was used to assess the factors affecting adoption ICT and a selectivity-corrected ordinary least square regression model was utilized to estimate the synergistic effect of ICT adoption and access to credit on the income of small-scale sugarcane farmers. Results and discussion: The findings revealed that approximately 77% of small-scale farmers had access to credit, while more than 80% had adopted ICT. The results derived from the recursive bivariate probit (RBP) regression model indicated that access to credit, education, and extension support positively and significantly influenced the adoption of ICT. Conversely, marital status and non-farm income exhibited a negative and significant influence on the adoption of ICT. Gender and marital status were positively and significantly associated with access to credit, whereas age, education, and non-farm income showed a negative and significant relationship on access to credit. Subsequently, a selectivity-corrected ordinary least square regression model analysis revealed that factors such as gender, marital status, extension, government support, and transportation costs positively and significantly influenced farmer's income. In contrast, education, employment status, and non-farm income exhibited a negative and significant influence on income. Conclusion and recommendations: The study concludes that socio-demographic factors, such as gender, marital status, extension support, government support, and transportation costs, positively contribute to farmers' income. Small-scale sugarcane farmer involvement in other non-farm activities is associated with reduced farm income. This implies that farmers' livelihoods options are reduced as they can only focus on sugarcane development as a source of income. There is a pressing need to educate small-scale farmers on ICT and provide them with access to agricultural credit. Additionally, extension workers should offer advisory support to small-scale farmers requiring assistance in accessing agricultural credit. There is a need to train sugarcane farmers on different agricultural income generating activities to reduce their over-reliance on sugarcane development. By addressing the identified socio-demographic factors and implementing targeted policy interventions, stakeholders can foster an enabling environment for small-scale farmers to thrive, ultimately contributing to the sustainable development of the sugarcane sector and the broader agricultural landscape in South Africa.

4.
Geoderma Reg ; 37: e00817, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39015345

RESUMEN

Soil organic carbon (SOC) stocks are critical for land management strategies and climate change mitigation. However, understanding SOC distribution in South Africa's arid and semi-arid regions remains a challenge due to data limitations, and the complex spatial and sub-surface variability in SOC stocks driven by desertification and land degradation. Thus, to support soil and land-use management practices as well as advance climate change mitigation efforts, there is an urgent need to provide more precise SOC stock estimates within South Africa's arid and semi-arid regions. Hence, this study adopted remote-sensing approaches to determine the spatial sub-surface distribution of SOC stocks and the influence of environmental co-variates at four soil depths (i.e., 0-30 cm, 30-60 cm, 60-100 cm, and 100-200 cm). Using two regression-based algorithms, i.e., Extreme Gradient Boosting (XGBoost) and Random Forest (RF), the study found the former (RMSE values ranging from 7.12 t/ha to 29.55 t/ha) to be a superior predictor of SOC in comparison to the latter (RMSE values ranging from 7.36 t/ha to 31.10 t/ha). Nonetheless, both models achieved satisfactory accuracy (R2 ≥ 0.52) for regional-scale SOC predictions at the studied soil depths. Thereafter, using a variable importance analysis, the study demonstrated the influence of climatic variables like rainfall and temperature on SOC stocks at different depths. Furthermore, the study revealed significant spatial variability in SOC stocks, and an increase in SOC stocks with soil depth. Overall, these findings enhance the understanding of SOC dynamics in South Africa's arid and semi-arid landscapes and emphasizes the importance of considering site specific topo-climatic characteristics for sustainable land management and climate change mitigation. Furthermore, the study offers valuable insights into sub-surface SOC distribution, crucial for informing carbon sequestration strategies, guiding land management practices, and informing environmental policies within arid and semi-arid environments.

5.
Foods ; 12(19)2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37835206

RESUMEN

Achieving sustainable and healthy food systems in support of human and planetary health is a global challenge. We systematically reviewed papers (n = 2322) showing how village chicken products (meat, eggs, and offal) contribute to sustainable and healthy food systems for children along a rural-urban gradient. A total of 72 articles, representing all different sections covered in this review, were finally included. Production of village chickens contributed positively on livestock-derived food consumption by children. Households who owned chickens were likely to move from medium to high dietary diversity. Children from households that owned chickens had lower odds of anemia (1.07) and higher height-for-age (HAZ) and weight-for-age (WAZ) scores. Egg intervention increased HAZ and WAZ for children by 0.63 [95% confidence interval (CI), 0.38-0.88] and 0.61 [95% CI, 0.45-0.77], respectively. Village chicken ownership had positive effect on children's poultry meat and egg consumption. Per capita consumption of chicken by girls and boys combined was 38.2 g/day, where girls had 36.9 g/day and boys had 39.4 g/day. Children from households that owned chickens consumed eggs 2.8 more times per week compared to children from households without chickens. Moving along a rural-urban gradient, village chicken production was less common. Improved production and quality of village chicken products, and policies supporting optimal maternal and child intake these products are required.

6.
Front Sustain Food Syst ; 7: 1091333, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37701859

RESUMEN

Introduction: High crop productivity has the potential to improve the food and nutrition security status of not only smallholder farmers but also households in general. However, smallholder farmers operate in a dynamic environment whereby their crop production is affected by various factors that hinder it from lessening food insecurity and malnutrition in rural areas. The study investigated the determinants of crop productivity and its effect on household food and nutrition security status in South Africa. Methods: This study employed a quantitative research method. A total of 1520 households were selected using the multi-stage stratified random sampling technique. Out of the total sample size of 1520, 386 were crop producers, 176 producers were from Mpumalanga province, and 210 producers were from the Limpopo province. Results and discussion: Most of the smallholder farmers do not have access to the irrigation system, mechanization, and agricultural inputs. The Household Food Insecurity Access Scale showed that most smallholder farmers were food insecure, with 78% of the farmers in each province found to be food insecure. The results from Household Dietary Diversity Score (HDDS) showed that in the overall sampled population, 50% of smallholder farmers had highly diverse diets. Only 50% of the smallholder farmers had high dietary diversity in each province. Irrigation systems and involvement in crop production had a positive influence on the crop productivity of smallholder farmers. The results from the Conditional Mixed Process (CMP) model showed that ownership of livestock, harvest, and disability in the family negatively impacted smallholder farmers' food security status while household size had a positive effect on the food security of smallholder farmers. The results also showed that social grants, agricultural assistance, and harvest had a negative impact on the nutrition status of smallholder farmers. While household size had a positive impact on the nutrition status of smallholder farmers. Conclusion and recommendations: Factors such as irrigation systems and involvement in crop production influenced crop productivity. Household size influenced the nutritional status of smallholder farmers while harvest size affected the food security status. There is a need to encourage more households to get involved in farming. Government and nongovernmental organizations need to support smallholder farmers with agricultural productive resources like irrigation systems to improve their crop productivity.

7.
Front Biogeogr ; 15(2): e59408, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37680769

RESUMEN

The mopane worm (Gonimbrasia belina) is an edible insect distributed across southern Africa. As a culturally important source of food, the mopane worm provides nutrition, livelihoods and improves wellbeing for rural communities across its range. However, this is strong evidence that insect populations are declining worldwide, and climate change is likely to cause many insect species to shift in their distributions. For these reasons, we aimed to model how the ecosystem service benefits of the mopane worm are likely to change in the coming decades. We modelled the distribution of the mopane worm under two contrasting climate change scenarios (RCPs 4.5 and 8.5). Moreover, given that the mopane worm shows strong interactions with other species, particularly trees, we incorporated biotic interactions in our models using a Bayesian network. Our models project significant contraction across the species' range, with up to 70% decline in habitat by the 2080s. Botswana and Zimbabwe are predicted to be the most severely impacted countries, with almost all habitat in Botswana and Zimbabwe modelled to be lost by the 2080s. Decline of mopane worm habitat would likely have negative implications for the health of people in rural communities due to loss of an important source of protein as well as household income provided by their harvest. Biogeographic shifts therefore have potential to exacerbate food insecurity, socio-economic inequalities, and gender imbalance (women are the main harvesters), with cascading effects that most negatively impact poor rural communities dependent on natural resources.

8.
Sustainability ; 15(5): 3936, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-37680852

RESUMEN

The sustainability of agroecosystems is at risk owing to continuous anthropogenic disturbance. As such, there is a need to evaluate indicator taxa that may be used to monitor the health of agricultural management systems. Carabid beetles are ubiquitous and functionally crucial in agroecosystems while at the same time are sensitive to the changes caused by management practices. Their quick response to anthropogenic disturbances has been proposed as a practical and realistic tool for monitoring the sustainability of agricultural practices. However, there is still disagreement about carabids as possible indicators of agroecosystem sustainability. We conducted a systematic review of the responses of carabid beetles to agricultural systems in different biogeographical areas. We examined whether these beetles could serve as potential indicators of agroecosystem sustainability. The ISI Web of Science, Google Scholar, and Scopus were used to search for papers published from 2000-2019. In total, we included 69 studies indicating the use of carabids to monitor the impact of management practices in agroecosystems. Most studies were conducted in European countries (n = 37), while Southern Africa and East Asia countries were significantly under-represented (n = 10). Carabid beetle response to agroecosystems varied between management practices, with biodiversity indices (n = 41: positive 60%, negative 19%, and neutral 19%) being the most measured response variable, followed by functional diversity (n = 28: positive 67%, negative 25%, and neutral 7%). Overall, our findings highlight the need for more research in underdeveloped countries, to investigate the potential of overlooked carabids and include response variables measuring functional diversity in assessing the sustainability of agricultural management. This will assist policy makers and land managers in making active and informed decisions about agroecological disturbances and management.

9.
Agriculture (Basel) ; 13(3): 595, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-37693124

RESUMEN

The importance of smallholder farming is increasingly recognized in rural areas where increased crop productivity and market participation can effectively improve their dietary diversity and nutrition quality. However, rural households are still faced with severe food insecurity and malnutrition. The study sought to assess the role of smallholder farming in crop productivity and market access on rural household dietary diversity. The secondary data were collected using a quantitative research method, and 1520 participants were selected using a stratified random sampling technique. The descriptive results showed that cereals were the most (98%) consumed food group, while vegetables and fruits were the least consumed food groups, at 37% and 23%, respectively. The results from the Household Dietary Diversity Score (HDDS) showed that 57% of smallholder farmers consumed highly diverse diets (more or equal to six food groups), whereas 25% and 18% of smallholder farmers consumed medium dietary diversity (four to five food groups) and low diverse diets (less or equal to three food groups), respectively. The findings from the Conditional Mixed Process (CMP) and Poisson endogenous treatment effect models showed that household size, ownership of livestock, wealth index, and involvement in crop production positively influenced household dietary diversity. On the other hand, output and access to market information showed a negative effect. Social grants had contradicting effects: they had a negative impact on the HDDS received from crop productivity while they had a positive effect on the HDDS from market participation. Providing different ways smallholder farmers can use their funds effectively can help improve household dietary diversity and nutrition quality. The study recommended that more workshops and training be conducted that cover all the sustainable production systems that smallholder farmers can undertake to produce different food groups. These will raise awareness among smallholder farmers about the requirements for balanced diets for food and nutrition security.

10.
Front Sustain Food Syst ; 7: 867481, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37693217

RESUMEN

South Africa faces the triple burden of malnutrition, high poverty levels, unemployment, and inequality. "Wicked problems" such as these require innovative and transdisciplinary responses, multi-stakeholder coordination and collaboration, managing complex synergies and trade-offs, and achieving sustainable outcomes. Through qualitative content analysis of national and provincial sector-based policies, we explored the interlinkages between the agriculture, environment, and health sectors in South Africa in the context of sustainable food and nutrition security and the extent to which these interlinkages are integrated into policy and planning. A systemic analysis of the review outcomes was performed to identify its main learning outcome, the status quo in the policy process. The nature of feedback loops was identified, and a leverage point was suggested. The review highlighted that policymakers in the agriculture, environment and health sectors are aware of, and have understood, the relationships among the three sectors. They have also made attempts to address these interlinkages through collaboration and coordination. Unfortunately, this has been met with several challenges due to fragmented sector-specific mandates and targets and a lack of resources for integrated solutions. This creates implementation gaps and unintended duplication of activities, leading to poor service delivery. Transitioning to sustainable and healthy food systems will only be possible after these gaps have been closed and implementation optimization has been achieved. Focusing on meta-level problem-framing, functional collaboration through transdisciplinary approaches, and integrated targets are critical to successful policy implementation and progressive realization of national goals related to sustainable food and nutrition security, unemployment, poverty, and inequality.

11.
Trop Anim Health Prod ; 55(3): 204, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37195342

RESUMEN

Goats are a common ruminant in livestock husbandry systems in communal areas of southern Africa, but less so in peri-urban areas. While dynamics of goat farming in the former are relatively well-understood, little is known about it in peri-urban environments. We investigated the contribution of small-scale farming of goats to household livelihoods in rural and peri-urban areas in KwaZulu-Natal Province of South Africa. We used a semi-structured questionnaire survey to elicit views of 115 respondents on the contribution of goats to household income at two rural (Kokstad, Msinga) and two peri-urban (Howick, Pietermaritzburg) locations. Goats contributed to household income as a source of cash and meat in various sociocultural contexts such as at weddings, funerals and festive period gatherings (e.g. Easter and Christmas), including payment for household needs and expenses including food, school fees and medico-cultural consultations. These findings were more pronounced in rural areas, where more goats were kept than in peri-urban areas, which also had smaller herds per household. Goats were a source of cash in numerous ways including sales of their skins after slaughter and use of skins through value addition to make household craft items such as stools that could be sold for cash. None of the farmers milked their goats. Goat famers also kept cattle (52%), sheep (23%) and chickens (67%). Goat ownership appeared to be more profitable in rural areas and contributed to a lesser extent as a source of income in peri-urban areas where goats were largely kept for sale. There is potential for increased value addition of goat products to increase returns from small-scale goat farming in rural and peri-urban settings. Artefacts and cultural symbols derived from goat products are pervasive amongst Zulu people, and represent an additional avenue of research into 'hidden' valuation of goats.


Asunto(s)
Crianza de Animales Domésticos , Pollos , Animales , Bovinos , Ovinos , Sudáfrica , África Austral , Cabras
12.
PLoS One ; 18(2): e0265054, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36735747

RESUMEN

Resource partitioning promotes coexistence among guild members, and carnivores reduce interference competition through behavioral mechanisms that promote spatio-temporal separation. We analyzed sympatric lion and spotted hyena movements and activity patterns to ascertain the mechanisms facilitating their coexistence within semi-arid and wetland ecosystems. We identified recurrent high-use (revisitation) and extended stay (duration) areas within home ranges, as well as correlated movement-derived measures of inter- and intraspecific interactions with environmental variables. Spatial overlaps among lions and hyenas expanded during the wet season, and occurred at edges of home ranges, around water-points, along pathways between patches of high-use areas. Lions shared more of their home ranges with spotted hyenas in arid ecosystems, but shared more of their ranges with conspecifics in mesic environments. Despite shared space use, we found evidence for subtle temporal differences in the nocturnal movement and activity patterns between the two predators, suggesting a fine localized-scale avoidance strategy. Revisitation frequency and duration within home ranges were influenced by interspecific interactions, after land cover categories and diel cycles. Intraspecific interactions were also important for lions and, important for hyenas were moon illumination and ungulates attracted to former anthrax carcass sites in Etosha, with distance to water in Chobe/Linyanti. Recursion and duration according to locales of competitor probabilities were similar among female lions and both sexes of hyenas, but different for male lions. Our results suggest that lions and spotted hyenas mediate the potential for interference competition through subtle differences in temporal activity, fine-scale habitat use differentiation, and localized reactive-avoidance behaviors. These findings enhance our understanding of the potential effects of interspecific interactions among large carnivore space-use patterns within an apex predator system and show adaptability across heterogeneous and homogeneous environments. Future conservation plans should emphasize the importance of inter- and intraspecific competition within large carnivore communities, particularly moderating such effects within increasingly fragmented landscapes.


Asunto(s)
Carnívoros , Hyaenidae , Leones , Acecho , Animales , Masculino , Femenino , Ecosistema
13.
Psychol Health Med ; 28(9): 2441-2449, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36821547

RESUMEN

Clean water and sanitation provisions are essential for good hygiene and health, with rural South Africa facing a simultaneous access crisis of both, the direct health effect of restricted access to both on mental health remaining scarce and largely overlooked. This study investigated the association between access to clean water and sanitation on depression in rural South Africa utilizing the most recent data (year 2017) from the South African National Income Dynamics Study. Our study outcome was depression, based on the 10-item abridged version of the Center for Epidemiologic Studies Depression Scale (data available in SA-NIDS), the main exposures being access to clean water and adequate sanitation facilities (i.e. flushing toilets). Two types of analyses were conducted: first, adjusted logistic regression models were fitted to assess the relationship between lack of access to clean water and adequate sanitation to depression. Second, we conducted mediation analysis to investigate whether access to clean water mediated the relationship between lack of access to toilets and depression. A high proportion of rural participants lacked access to clean water (n = 6,188, 47.6%) and adequate toilets (n = 9,797, 81.6%). The regression analyses indicated that lack of access to both clean water (OR = 1.21, 95% CI: 1.06-1.39) and adequate sanitation (OR = 1.36, 95% CI: 1.10-1.69) were significantly associated with greater odds of depression. The mediation analysis indicated that access to clean water partially mediated the relationship between lack of access to adequate sanitation and depression, the total mediated effect being 18.2% (95% CI: 11.0%-51.0%). Most rural communities in South Africa lack access to basic services that are essential for human dignity and a decent quality of life, leading to opportunities for poor mental health, with its various consequences for socio-economic development and personal wellbeing, including avoidable depression.


Asunto(s)
Saneamiento , Abastecimiento de Agua , Humanos , Sudáfrica/epidemiología , Población Rural , Agua , Depresión/epidemiología , Calidad de Vida
14.
Front Nutr ; 10: 1060246, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36793925

RESUMEN

Introduction: Intercropping cereals with legumes can intensify rainfed cereal monocropping for improved household food and nutritional security. However, there is scant literature confirming the associated nutritional benefits. Methodology: A systematic review and meta-analysis of nutritional water productivity (NWP) and nutrient contribution (NC) of selected cereal-legume intercrop systems was conducted through literature searches in Scopus, Web of Science and ScienceDirect databases. After the assessment, only nine articles written in English that were field experiments comprising grain cereal and legume intercrop systems were retained. Using the R statistical software (version 3.6.0), paired t-tests were used to determine if differences existed between the intercrop system and the corresponding cereal monocrop for yield (Y), water productivity (WP), NC, and NWP. Results: The intercropped cereal or legume yield was 10 to 35% lower than that for the corresponding monocrop system. In most instances, intercropping cereals with legumes improved NY, NWP, and NC due to their added nutrients. Substantial improvements were observed for calcium (Ca), where NY, NWP, and NC improved by 658, 82, and 256%, respectively. Discussion: Results showed that cereal-legume intercrop systems could improve nutrient yield in water-limited environments. Promoting cereal- legume intercrops that feature nutrient-dense legume component crops could contribute toward addressing the SDGs of Zero Hunger (SDG 3), Good Health and Well-3 (SDG 2) and Responsible consumption and production (SDG 12).

15.
Diversity (Basel) ; 15(12): 1187, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-39006477

RESUMEN

Grazing practices affect the soil and vegetation of grasslands, which further influence the provision of ecosystem services and the productivity of grasslands. We determined the ecosystem resilience of a mesic grassland under three grazing management systems in the Pakkies area, (30°33'08''S, 29°25'22'' E), South Africa: cooperative (continuously grazed since 2017), commercial (rotationally grazed for >20 years), and communal (continuously grazed for >20 years) farms. This was carried out by measuring the penetration resistance and infiltration, soil nutrients, forage quality contents for livestock, veld condition, plant species composition and richness, and functional diversity. The soils had a higher penetration resistance in the continuously grazed communal farm, while water infiltration was highest in the continuously grazed cooperative farm. The plant species and functional diversity were greater in the rotationally grazed commercial farm than in the continuously grazed communal and cooperative farms. The continuously grazed cooperative farm had the highest veld condition score (97%), while the rotationally grazed commercial and the continuously grazed communal farms had 82% and 56% veld condition scores, respectively. The forage quality and soil nutrients were generally similar among all farms. The lower plant diversity observed with continuous grazing may indicate that the ecological system was not as resilient concerning this type of grazing. However, for forage quality, soil nutrients and veld condition, continuous grazing was resilient, which indicates that rotational grazing may not be better than continuous grazing for livestock production in this specific region. As long as a minimum level of ecological resilience can be retained, continuous grazing can sustain effective animal production, particularly for small-holder farmers.

16.
Cogent Food Agric ; 9(2): 2280365, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-39005879

RESUMEN

Developing countries in Africa face an unemployment crisis, with many unemployed youth. Agriculture has been identified as a strategic sector for employment creation targeted at youth, including those who may not have agriculture-related qualifications. However, various challenges limit the effectiveness of youth participation in the agriculture value chain. The study aimed to (i) determine youth awareness of agricultural value-chain opportunities, (ii) determine their perception of their role in the value chain, (iii) determine their perception of agricultural programs targeting youth and their opinions on who is responsible for attracting youth into agriculture and, (iv) to characterise the dynamics of youth empowerment in agriculture. Data was collected using focus group discussions and an online survey and analysed using SPSS and NVivo. Poor knowledge, low levels of awareness of agricultural value-chain activities and careers, and not meeting the minimum requirements for employment in processing and retail businesses were identified as key challenges. Most youth were interested in non-primary activities such as agro-processing, which are less labour-intensive and have a quicker return on investment than agricultural production. However, support services and programs for promoting youth participation in agriculture mainly focus on primary activities, signifying a mismatch between youth aspirations and current support. Understanding youth aspirations, perceptions and dynamics underpinning youth empowerment and participation in value chains is critical for promoting participation and formulating relevant and responsive policies. Additionally, improving access to information and building awareness of agricultural value chains is crucial in reducing barriers to entry. Policymakers should integrate agriculture and food systems knowledge into the primary education curriculum to promote youth awareness and evoke interest in agri-food system careers at an early age.

17.
Remote Sens (Basel) ; 15(23): 5461, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-39007071

RESUMEN

Due to the need to continuously monitor and understand the thermal environment and its socioeconomic implications, this study used remotely sensed data to analyze thermal comfort variation in LCZs, including along the rural to urban gradient of the eThekwini Municipality in KwaZulu-Natal province of South Africa. LCZs were mapped using multi-temporal and multi-spectral Landsat 8 and Landsat 9 data using the approach by World Urban Database and Access Portal Tools (WUDAPT), while thermal data were used to retrieve land surface temperatures (LSTs). Data for training classification of LCZs and accuracy assessment were digitized from GoogleEarth guided by knowledge gained and data collected during a field survey in March 2022 as well as pre-existing maps. LCZs were mapped using the random forest classifier in SAGA GIS software while a single channel algorithm based on band 10 was used to compute LST for different scenes. The LSTs were adjusted and further used to derive thermal comfort based on the Universal Thermal Comfort Index (UTCI) categories as an indicator for outdoor thermal comfort on the extremely low- and extremely high-temperature periods in the cool and hot seasons, respectively. LCZs were mapped with high accuracy (overall accuracy of 90.1% and kappa of 0.88) while inter-class separability was high (>1.5) for all LCZ pairs. Built-up LCZs dominate the eastern parts of the municipality, signifying the influence of the sea on development within the area. Average LST was coolest in the dense forest, open low-rise and water LCZs in the cool and hot seasons, respectively. The compact high-rise LCZ was the warmest in both the hot (36 °C) and the cool (23 °C) seasons. The sea sands were among coolest regions in both seasons due to their high water content, attributed to their high water table and close proximity to the ocean. There was no thermal stress during the cool season, while most areas recorded moderate to strong heat stress in the hot season. Some areas in the densely built-up LCZs recorded very strong heat stress in the hot season. The findings suggest that policies and strategies should enhance heat mitigation capacities in strong-heat-stress areas during the hot season. Municipal authorities and citizens must work together to build strategies to minimize temperature extremes and associated socioeconomic pressures. Urban development policies, plans and strategies should consider implications on the thermal environment as well as the value of conservation of LCZs with high-heat mitigation value such as dense forests and expansion of built-up LCZs with low-heat absorption levels such as open low-rise. The study was based mainly on remotely sensed temperatures with some ground data used to validate results, which may limit the assessment. Overall, the study provides insights towards achievement of global sustainable and climate-smart development targets.

18.
Sci Rep ; 12(1): 22008, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36550171

RESUMEN

For large herbivores living in highly dynamic environments, maintaining range fidelity has the potential to facilitate the exploitation of predictable resources while minimising energy expenditure. We evaluate this expectation by examining how the seasonal range fidelity of African elephants (Loxodonta africana) in the Kruger National Park, South Africa is affected by spatiotemporal variation in environmental conditions (vegetation quality, temperature, rainfall, and fire). Eight-years of GPS collar data were used to analyse the similarity in seasonal utilisation distributions for thirteen family groups. Elephants exhibited remarkable consistency in their seasonal range fidelity across the study with rainfall emerging as a key driver of space-use. Within years, high range fidelity from summer to autumn and from autumn to winter was driven by increased rainfall and the retention of high-quality vegetation. Across years, sequential autumn seasons demonstrated the lowest levels of range fidelity due to inter-annual variability in the wet to dry season transition, resulting in unpredictable resource availability. Understanding seasonal space use is important for determining the effects of future variability in environmental conditions on elephant populations, particularly when it comes to management interventions. Indeed, over the coming decades climate change is predicted to drive greater variability in rainfall and elevated temperatures in African savanna ecosystems. The impacts of climate change also present particular challenges for elephants living in fragmented or human-transformed habitats where the opportunity for seasonal range shifts are greatly constrained.


Asunto(s)
Elefantes , Incendios , Animales , Humanos , Ecosistema , Estaciones del Año , Elefantes/fisiología , Sudáfrica
19.
Environ Res Lett ; 17(8): 084017, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35928217

RESUMEN

Agricultural production in arid and semi-arid regions is particularly vulnerable to climate change, which, combined with projected food requirements, makes the sustainable management of water resources critical to ensure national and global food security. Using South Africa as an example, we map the spatial distribution of water use by seventeen major crops under current and future climate scenarios, and assess their sustainability in terms of water resources, using the water debt repayment time indicator. We find high water debts, indicating unsustainable production, for potatoes, pulses, grapes, cotton, rice, and wheat due to irrigation in arid areas. Climate change scenarios suggest an intensification of such pressure on water resources, especially in regions already vulnerable, with a country-scale increase in irrigation demand of between 6.5% and 32% by 2090. Future land use planning and management should carefully consider the spatial distribution and local sustainability of crop water requirements to reduce water consumption in water risk hotspots and guarantee long-term food security.

20.
PLoS One ; 17(6): e0270756, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35767595

RESUMEN

Global broiler production and consumption levels continue to rise. South Africa's broiler system is dominated by commercial production and formal retail trade, with competition from cheap imports. Local broiler policies have narrow, production-driven, short-term aims for industry growth and national food security. However, these have unintended consequences that undermine the system's future sustainability. Using a food systems approach, this study developed a qualitative system dynamics model of the South African commercial broiler system and used it to engage stakeholders in policy discussions within the boundaries of health, nutrition, and environmental sustainability. A problem statement and key system elements were drawn from a previously published qualitative study and were validated by 15 stakeholders via an online questionnaire. From this, a seed model was developed, expanded into a larger model, and shared in a modular format with stakeholders in virtual meetings, on an individual or institutional basis, for feedback and validation, and for discussion of areas for policy consideration. Refinements were incorporated into the modules, policy considerations were summarised, and crosscutting issues were identified. The model demonstrated the system's complexity, interlinkages, feedbacks, reinforcing and balancing loops, and behaviour archetypes. The modular presentation format created a suitable platform for stakeholder engagement. Current policies focus on local commercial production, formal markets, and affordability without cognisance of the broader system represented by the model. Inequality pervades throughout the system. Commercial producers, linked to large supermarkets and fast-food chains, dominate the system, presenting barriers to entry. Affordability is unintentionally traded off against non-communicable disease risks through brining of most frozen products, and ultra-processing of fast-food items. Foodborne disease control is critical, given the proportion of vulnerable individuals, and greater coherence of food safety policy is urgently needed. The environmental footprint of broilers, whilst less than that of ruminants, deserves closer scrutiny based on its dependence on intensive cereal production for feed. This study's food systems approach provides a system-wide perspective and a foundation for policymakers to develop more integrated and transformative policies.


Asunto(s)
Pollos , Política Nutricional , Animales , Alimentos , Sudáfrica , Análisis de Sistemas
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