Application of sentinel-2 multispectral images for monitoring water hyacinth: a case study in the Lower Mondego (Portugal)
DOI:
https://doi.org/10.14195/1647-7723_31-1_6Keywords:
Water resources, invasive aquatic plants, remote sensing, satellite, vegetation indicesAbstract
Highly invasive exotic species have become a severe threat in many regions of the world due to the consequent reduction of biodiversity, resulting in high environmental and economic costs. Regarding aquatic weeds, especially in vulnerable surface water bodies, this problem is particularly serious. Inherent difficulties in monitoring aquatic invasive plants with conventional methods have led to the use of remote sensing tools for this purpose. This study explores the role of Sentinel-2 satellite data in detecting, mapping, and monitoring the water hyacinth (Eichhornia crassipes) in rivers, giving as an example the use of this technology to study this aquatic weed in watercourses in the Lower Mondego region (Portugal). Multispectral-based vegetation indices are used for this purpose. This approach can contribute significantly to the timely definition of management measures aimed at controlling the water hyacinth’s infestation of water bodies, such measure being crucial to ensuring the multiple functions of these water bodies and preventing associated environmental risks.
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