A reflection about the recent Koedoe publications (Volume 64, No 1, 2022)

No abstract available.http://www.koedoe.co.zaam2023Geography, Geoinformatics and Meteorolog

Assessing the effect of seasonality on leaf and canopy spectra for the discrimination of an alien tree Species, Acacia Mearnsii, from co-occurring native species using parametric and nonparametric classifiers

The tree Acacia mearnsii is native to south-eastern Australia but has become an aggressive invader in many countries. In South Africa, it is a significant threat to the conservation of biomes. Detecting and mapping its early invasion is critical. The current ground-based methods to map A. mearnsii are accurate but are neither economical nor practical. Remote sensing (RS) provides accurate and repeatable spatial information on tree species. The potential of RS technology to map A. mearnsii distributions remains poorly understood, mainly due to a lack of knowledge on the spectral properties of A. mearnsii relative to co-occurring native plants. We investigated the spectral uniqueness of A. mearnsii compared to co-occurring native plant species within the South African landscape. We explored full-range (400-2500 nm), leaf and canopy hyperspectral reflectance of the species. The spectral reflectance was collected biweekly from December 23, 2016 and May 31, 2017. We conducted a time series analysis, to assess the effect of seasonality on species discrimination. For comparison, two classification models were employed: parametric interval extended canonical variate discriminant (iECVA-DA) and nonparametric random forest discriminant classifiers (RF-DA). The results of this paper suggest that phenology plays a crucial role in discriminating between A. mearnsii and sampled species. The RF classifier discriminated A. mearnsii with slightly higher accuracies (from 92% to 100%) when compared with the iECVA-DA (from 85% to 93%). The study showed the potential of RS to discriminate between A. mearnsii and co-occurring plant species.The Council for Scientific and Industrial Research and the National Research Foundation (NRF).http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=36hj2020Plant Production and Soil Scienc

Assessing natural resource change in Vhembe biosphere and surroundings

South Africa is a custodian of an immense wealth of natural and biodiversity resources in Africa. Natural resources are continually changing in different South African biospheres based on anthropogenic and non-anthropogenic causes. Land use activities like agriculture, cultivation, livestock rearing, commercial plantations, urbanisation and mining are among the major drivers of natural resource change and transformation. In this study, land cover change assessment was used to assess natural resource change in Vhembe biosphere and surroundings. To assess natural resource change in Vhembe biosphere, land use land cover change assessment was conducted using South African’s national land-cover dataset, generated from multi-seasonal Landsat 5 and Sentinel-2 images. The 72× class land cover map was re-classified into 12× classes to fit the study objectives. Eight out of twelve classes quantified in hectares: indigenous forests, thicket/dense bush, natural woodland, shrubland, grassland, water bodies and wetlands were categorised as natural resources for which the natural resource change assessment for this study was based. Assessment findings established that land use and its related activities have contributed substantially to natural resource change where cultivated commercial, natural woodland and built-up residential contributed the most significant upward change in hectarage and percentage, from 132,246.9 to 365,644.92 (ha)—percentage change of 176%; from 94,665.42 to 257,889.68 (ha)—percentage changes of 172% and from 74,070.27 to 147,701.88(ha)—percentage change of 99% respectively. Shrubland, thicket/dense bush and indigenous forests registered the highest downward changes from 263,070.6 to 977.72 (ha); from 338,723.7 to 23,166.92 and from 13,211.91 to 7402.92 (ha) with percentage changes of −100%, −93% and −44% respectively in Vhembe biosphere and the surroundings from 1990 to 2018. The study showed how natural resources are changing and the use of remote sensing for environmental monitoring and assessment in the Vhembe district.http://link.springer.com/journal/10661hj2022Geography, Geoinformatics and Meteorolog

Mechanisms and consequences of benefit sharing from oil palm agribusiness plantations establishment in South Comoé Region, Côte d’Ivoire

One of the main difficulties facing agribusiness development in Cote d’Ivoire, is the issue of benefit sharing. Although communal land is expected to be equitably beneficial to all who have a stake on the land, unclear benefit sharing principles and modalities affect the implementation of benefit sharing to the disadvantage of the rural communities. Using a qualitative research approach, the study investigates if the benefit sharing approach practiced by oil palm plantations investors in South Comoé align with globally established standards of access and benefit sharing (ABS). To this end data for the study was collected from 50 participants: rural community members (N=36), agribusiness developers (N=6) and local government authorities (N=8). The results revealed inequality in the land acquisition and benefit sharing negotiation process in favour of local elites. Lack of fairness experienced in the benefit sharing approach in the districts of Aboisso, Bonoua and Adiaké was attributed to the lack of institutional, policy and legal frameworks to guide a fair benefit sharing. Inequality in benefit sharing scheme affects the working relationship between the parties thus generating tensions with consequences on the stability of commercial farming. The study contributes to the debate on the marginalisation of smallholders in the distribution of benefits from agribusiness investments. Therefore, the designing of policies and practical measures that bring together rural communities and agribusiness developers to negotiate fair benefit sharing terms in line with international standards including honesty, inclusive participation of rural community in land acquisition process are recommended

Seasonal evaluation and mapping of aboveground biomass in natural rangelands using Sentinel-1 and Sentinel-2 data

DATA AVAILABILITY : All the Sentinel data are free of cost and are in the open domain, and field data port the published claims and fulfill with field requirements.Rangelands play a vital role in developing countries’ biodiversity conservation and economic growth, since most people depend on rangelands for their livelihood. Aboveground-biomass (AGB) is an ecological indicator of the health and productivity of rangeland and provides an estimate of the amount of carbon stored in the vegetation. Thus, monitoring seasonal AGB is important for understanding and managing rangelands’ status and resilience. This study assesses the impact of seasonal dynamics and fire on biophysical parameters using Sentinel-1 (S1) and Sentinel-2 (S2) image data in the mesic rangeland of Limpopo, South Africa. Six sites were selected (3/ area), with homogenous vegetation (10 plots/site of 30m2). The seasonal measurements of LAI and biomass were undertaken in the early summer (December 2020), winter (July–August 2021), and late summer (March 2022). Two regression approaches, random forest (RF) and stepwise multiple linear regression (SMLR), were used to estimate seasonal AGB. The results show a significant difference (p < 0.05) in AGB seasonal distribution and occurrence between the fire (ranging from 0.26 to 0.39 kg/m2) and non-fire areas (0.24–0.35 kg/m2). In addition, the seasonal predictive models derived from random forest regression (RF) are fit to predict disturbance and seasonal variations in mesic tropical rangelands. The S1 variables were excluded from all models due to high moisture content. Hence, this study analyzed the time series to evaluate the correlation between seasonal estimated and field AGB in mesic tropical rangelands. A significant correlation between backscattering, AGB and ecological parameters was observed. Therefore, using S1 and S2 data provides sufficient data to obtain the seasonal changes of biophysical parameters in mesic tropical rangelands after disturbance (fire) and enhanced assessments of critical phenology stages.Open access funding provided by University of Pretoria.http://link.springer.com/journal/10661am2024Geography, Geoinformatics and MeteorologyPlant Production and Soil ScienceSDG-15:Life on lan

Exploring the integration of the land, water, and energy nexus in sustainable food systems research through a socio-economic lens : a systematic literature review

DATA AVAILABILITY STATEMENT : The data presented in this study are available on request from the corresponding author.The efficient use of land, water, and energy resources in Africa is crucial for achieving sustainable food systems (SFSs). A SFS refers to all the related activities and processes from farm to fork and the range of actors contributing to the availability of food at all times. This study aimed to analyse the growth in the land–water–energy (LWE) nexus integration in sustainable food system research. The focus was on publication growth, the thematic areas covered, and how the research addressed the policies, programmes, and practices using a socio-economic lens. The study utilised a systematic literature review approach, following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The study underscored the limited emphasis on the socio-economic perspective in the examination of the LWE nexus within sustainable food system research in Africa. Policies, governance, institutional influences, and social inclusion are crucial for addressing the region-specific challenges and achieving sustainable outcomes, but they seemed to be underrepresented in current research efforts. More so, this review revealed a paucity of research on key influencing factors like gender, conflict, culture, and socio-political dynamics. Ignoring these social factors might contribute to an inadequate management of natural resources, perpetuating issues related to food security and equity in resource use and decision-making. Additionally, the dominance of non-African institutions in knowledge production found in this review highlighted a potential gap in locally owned solutions and perspectives, which are crucial for effective policy development and implementation, often leading to failures in addressing region-specific challenges and achieving sustainable outcomes. Overall, the study highlighted the need for a more holistic approach that not only considers the technical aspects of the LWE nexus but also the social, cultural, and institutional dimensions. Additionally, fostering collaboration with local institutions and ensuring a diverse range of influencing factors can contribute to more comprehensive and contextually appropriate solutions for achieving sustainable food systems in Africa.The Bill & Melinda Gates Foundation.https://www.mdpi.com/journal/sustainabilityam2024Animal and Wildlife SciencesGeography, Geoinformatics and MeteorologySDG-02:Zero Hunge

Assessing species richness, diversity and assemblage of forest patches within a grassland matrix in the Afrotemperate ecosystems

Changes in species diversity have been widely used in environmental monitoring and global change studies as an indicator of vegetation change over time. High mountain ecosystems such as the Golden Gate Highlands National Park (GGHNP) host a relatively high number of plant species due to less human disturbances compared to the surrounding lowland areas. This study investigated the species richness and diversity in the Afrotemperate forest and woodland communities of the GGHNP. For vegetation classification, the TWINSPAN algorithm was firstly used to do a floristic analysis of thirty-two sampling plots and refined further using the Braun-Blanquet procedures and JUICE programmes. The Detrended Correspondence Analysis (DCA) and the phytosociological analysis of the vegetation data resulted in five plant communities and one sub-community across various topographic gradient. The Olinia emarginata–Podocarpus latifolius forest was found to be the most diverse forest whereas the Kiggelaria africana forest showed relatively lower species diversity. Species richness was also relatively high in the Olinia emarginata–Podocarpus latifolius forest plots, compared to the Leucosidea sericea–Buddleja salviifolia woodland, and the Euclea crispa–Protea caffra–roupelliae savannas. Data on plant assemblages and classification provide invaluable information for studies focussing on climate change, species distribution models and the associated bioclimatic variables. Understanding the importance and complexities of high mountains and forest ecosystems is therefore essential for developing effective conservation strategies.http://www.schweizerbart.de/journals/phytohj2024Geography, Geoinformatics and MeteorologySDG-15:Life on lan

Ecosystem service valuation for a critical biodiversity area : case of the Mphaphuli community, South Africa

The study of ecosystem services and the valuation of their contribution to human wellbeing is gaining increasing interest among scientists and decision-makers. The setting of this study was a critical biodiversity area on a portion of land largely presided over by a traditional leadership structure on behalf of a relatively poor local community in South Africa. The study identified several ecosystem services and performed an economic valuation of these services, and their importance both locally and globally using the Co$ting Nature V3 tool. The study identified ecosystem services such as the regulation of air quality, regulation of natural hazards, and provision of water. The economic valuation was carried out for all identified ecosystem services, realised and potential. The total realised economic value of ecosystem services was found to be US$528,280,256.00, whereas hazard mitigation potential was found to be US$765,598,080.00 across the study area. Artisanal fisheries were the least valued ecosystem service at US$5577.54. The values of the ecosystem services differed across the eleven land use land cover classes. The outcomes of the study focused on a very local scale, which was a departure from other studies previously carried out in South Africa, which focused more on the identification and valuation of regional and national scale ecosystem services.https://www.mdpi.com/journal/landam2023Geography, Geoinformatics and Meteorolog

Quantitative Assessment of Hab Watershed Using Geoinformatics

Morphometric assessment of the watersheds is considered highly critical to appraise its hydrological characteristics, such as, general geology, structure, geomorphology and climate conditions. In this study, morphometric analysis of Hab Watershed has been carried out through Geospatial Technology (RS &amp; GIS) in a systematic manner to examine its Geo-hydrological characteristics. The drainage network of Hab is typically dendritic and semi-dendritic indicating its heterogeneous lithology. Recent study reveals increase in stream order, substantially decreases the stream total length. drainage density of the Hab Watershed indicates the characteristics of its typical soil. Drainage texture value for Hab watershed is 0.18. Low drainage density value reveals that the region has a permeable and porous subsurface material with low relief. The shape of the basin has been observed as quite elongated. The findings of this study reveal that GIS based morphometric analysis is highly effective tool for geo-hydrological study of watersheds

Seasonal monitoring of biochemical variables in natural rangelands using Sentinel-1 and Sentinel-2 data

Rangelands are natural ecosystems that serve as essential sources of forage for domesticated livestock and wildlife. Therefore, accurately mapping nutrient levels in rangelands is crucial for sustainable development and effective management of grazing animals. Remote sensing tools offer a reliable means to explore nutrient concentrations across large spatial areas. This study aimed to estimate and map seasonal foliar concentrations of nitrogen (N), phosphorus, and neutral detergent fibre (NDF) in mesic tropical rangelands of Limpopo using Sentinel-1, Sentinel-2, and the integration of S1 and S2 data. Fieldwork was conducted to collect samples for seasonal foliar nutrients (N, P, and NDF) during early-summer (November-January 2020), winter (July-August 2021), and late-summer (February-March 2022). Various conventional and red-edge-based vegetation indices were computed. The results demonstrate that integration data from S1 and S2 can effectively estimate and predict foliar concentrations of N, P, and NDF in mesic rangelands throughout the seasons, achieving R2 values of 0.76, 0.78, and 0.71, with corresponding RMSE values of 0.13, 0.04, and 2.52. Notably, red-edge variables emerged as the most significant parameters for predicting seasonal N, P, and NDF concentrations. Additionally, factors such as season and slope significantly influenced the distribution and occurrence of these foliage nutrients, with higher foliage production observed during late-summer and on steeper slopes. The study concludes that the integration of S1 and S2 data can effectively monitor the seasonal dynamics of biochemical parameters. This finding holds significant implications for policymakers and rangeland users, offering a comprehensive understanding of the intricate variations within rangeland ecosystems. Further research could expand on these findings by applying the knowledge to various datasets, exploring different rangelands, and examining additional ecological factors such as slope altitude to detect foliar fibre biochemicals. Finally, the applications of this research extend beyond individual properties, providing practical tools for sustainable rangeland management and informed decision-making in resource utilization and conservation.http://www.tandfonline.com/loi/tres20hj2024Geography, Geoinformatics and MeteorologyPlant Production and Soil ScienceSDG-15:Life on lan