Research Artcicles (Geography & Environmental Studies)

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https://hdl.handle.net/10566/38

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Browsing by Subject "Agriculture"

Now showing 1 - 4 of 4
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    Assessing the prospects of remote sensing maize leaf area index using uav-derived multi-spectral data in smallholder farms across the growing season
    (MDPI, 2023) Buthelezi, Siphiwokuhle; Mutanga, Onisimo; Sibanda, Mbulisi
    Maize (Zea Mays) is one of the most valuable food crops in sub-Saharan Africa and is a critical component of local, national and regional economies. Whereas over 50% of maize production in the region is produced by smallholder farmers, spatially explicit information on smallholder farm maize production, which is necessary for optimizing productivity, remains scarce due to a lack of appropriate technologies. Maize leaf area index (LAI) is closely related to and influences its canopy physiological processes, which closely relate to its productivity. Hence, understanding maize LAI is critical in assessing maize crop productivity. Unmanned Aerial Vehicle (UAV) imagery in concert with vegetation indices (VIs) obtained at high spatial resolution provides appropriate technologies for determining maize LAI at a farm scale. Five DJI Matrice 300 UAV images were acquired during the maize growing season, and 57 vegetation indices (VIs) were generated from the derived images.
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    Crop monitoring in smallholder farms using unmanned aerial vehicles to facilitate precision agriculture practices: A scoping review and bibliometric analysis
    (MDPI, 2023) Gokool, Shaeden; Mahomed, Maqsooda; Sibanda, Mbulisi
    In this study, we conducted a scoping review and bibliometric analysis to evaluate the state-of-the-art regarding actual applications of unmanned aerial vehicle (UAV) technologies to guide precision agriculture (PA) practices within smallholder farms. UAVs have emerged as one of the most promising tools to monitor crops and guide PA practices to improve agricultural productivity and promote the sustainable and optimal use of critical resources. However, there is a need to understand how and for what purposes these technologies are being applied within smallholder farms. Using Biblioshiny and VOSviewer, 23 peer-reviewed articles from Scopus andWeb of Science were analyzed to acquire a greater perspective on this emerging topical research focus area.
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    Estimation of maize foliar temperature and stomatal conductance as indicators of water stress based on optical and thermal imagery acquired using an unmanned aerial vehicle (uav) platform
    (MDPI, 2022) Brewer, Kiara; Clulow, Alistair; Sibanda, Mbulisi
    Climatic variability and extreme weather events impact agricultural production, especially in sub-Saharan smallholder cropping systems, which are commonly rainfed. Hence, the development of early warning systems regarding moisture availability can facilitate planning, mitigate losses and optimise yields through moisture augmentation. Precision agricultural practices, facilitated by unmanned aerial vehicles (UAVs) with very high-resolution cameras, are useful for monitoring farm-scale dynamics at near-real-time and have become an important agricultural management tool. Considering these developments, we evaluated the utility of optical and thermal infrared UAV imagery, in combination with a random forest machine-learning algorithm, to estimate the maize foliar temperature and stomatal conductance as indicators of potential crop water stress and moisture content over the entire phenological cycle.
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    Urban agriculture and the sustainability nexus in South Africa: Past, current, and future trends
    (Springer, 2023) Kanosvamhira, Tinashe P.
    Urban agriculture remains a topical issue that needs to be better understood in striving for sustainable cities, particularly in sub-Saharan Africa. Through a literature review, this article examines urban agriculture studies in South Africa to identify trends, opportunities, and gaps in the literature. The article examines the discourses that have emerged based on a narrative literature review of 62 peer-reviewed articles from 1993 to 2022. The findings indicate that several gaps in the knowledge limit our understanding of the practice of urban agriculture toward sustainable cities, for instance, an under-representation of secondary cities and the general productivist focus of most studies in the country. The author argues that future research needs to focus on underrepresented cities using rich methodologies to gain further insights into urban agriculture and its place in the city.