Extent

Problem:

“There is very little information to accurately assess the degree to which areas are invaded." – Van Wilgen, B.W. & Wilson, J.R. (Eds.) 2018. The status of biological invasions and their management in South Africa in 2017. South African National Biodiversity Institute, Kirstenbosch and DST-NRF Centre of Excellence for Invasion Biology, Stellenbosch.

Solutions:

  • Holden et al. (2021) used a novel, transdisciplinary approach, combining Google Earth Engine’s processing power, freely available Sentinel imagery (fusion of Sentinel-1 and -2), expert engagement (including researchers, managers and decision makers), drone technology and field trips, to provide an accurate and up-to-date understanding of the occurrence and density of invasive alien trees in an important water tower for the south-western Cape of South Africa at a 20 m resolution.

  • Kotze et al. (2019, 2020) established and implemented a cost effective, objective and statistically sound invasive alien plant monitoring system at a quaternary catchment level (click here for data)

  • Royimani et al (2018) reviewed the advancements in satellite remote sensing for mapping and monitoring of Alien Invasive Plant species (AIPs)

  • Main et al. (2016) conducted an assessment of remote sensing techniques in the mapping of invasive alien plant distribution, tree cover and biomass, in the Agulhas plains

  • Van den Berg (2013) investigated the detection, quantification and monitoring of Prosopis spp. in the Northern Cape province using remote sensing and GIS (click here for data)

  • Van Wilgen & le Maitre (2013) reported on rates of spread in invasive plants of South Africa

  • Rouget et al. (2004) assessed the climatic correlates of distribution of 71 important invasive alien plants, and analysed the implications of these findings for future invasions in different vegetation types in South Africa, Lesotho and Swaziland over the next few decades