The CGA would like to say farewell to GIS & Earth Observation Analyst Atman Prins, who is leaving to take up a position in Dublin, Ireland. It has been a great pleasure working with Atman and the CGA would like to thank him for his time and dedication during the time he spent at [...]
Drone imagery is often used to calculate vegetation indices such as the normalized difference vegetation index (NDVI) to characterize the condition of individual trees in orchards. Individual trees are often defined as a centroid (centre of the tree), or a circle (buffer around the centroid) or a rectangular area (plot). The NDVI values are then extracted for these entities [...]
By Atman Prins Accurate crop type maps are important for obtaining agricultural statistics such as water use or harvest estimations. The traditional approach to obtaining maps of cultivated fields is by manually digitising the fields from satellite or aerial imagery. However, manual digitising is time-consuming, expensive and subject to human error. Automated remote sensing [...]
We are progressing well with the TerraClim project, and major milestone in the efficiency and accuracy of interpolations.The regional interpolation analysis divided the Western Cape study area into smaller regions using the local terrain and climatic characteristics of that particular region. The regionalisation of temperature interpolation showed improved accuracy of spatial interpolations by up [...]
by Atman Prins The second experiment used the methods developed for the first experiment to perform a five-class classification. The five classes consisted of maize, cotton, groundnuts, orchards and non-agriculture. Sentinel-2 and aerial imagery data were added to the analysis and were compared to LiDAR data. The LiDAR data was obtained from a 2016 [...]
This video is a flyover showing the results of a satellite image (WorldView-2 dated 15 March 2020) analysis of a citrus orchard draped over the Digital Elevation Model of South Africa at 2m resolution (DEMSA2). The analysis was carried out for agricultural research and innovation business CITRII. The automated analysis developed by [...]
Wynland has released part three of Winetech's flagship project, TerraClim, being undertaken by the CGA. For many wine grape producers in South Africa, access to accurate and detailed climate and GIS data is limited. Terraclim is funded by Winetech and is an online spatial decision-support system specifically [...]
This is a dense point cloud of a vineyard created with drone imagery with 4 bands (green, red ,red edge and near infrared). The imagery is displayed in false colour using the green , red and red edge bands. The dense point cloud was created using Agisoft Metashape and can be exported as a digital [...]
Prof Adriaan van Niekerk and Jascha Muller of the Centre for Geographical Analysis (CGA), and Dr Abraham Singels of the South African Sugarcane Research Institute (SASRI), have published their collaborative research assessing the use of multispectral remote sensing to determine fractional absorbed photosynthetically active radiation (fAPAR) in sugarcane. Crop growth models regularly use fAPAR as [...]