Identifying relevant hyperspectral bands using Boruta: a temporal analysis of water hyacinth biocontrol

The Impact of Simulated Spectral Noise on Random Forest and Oblique Random Forest Classification Performance

“…Experimental Procedure. Healthy water hyacinth (Eichhornia crassipes) plants (n = 90) were collected from the Amanzimtoti River located in the KwaZulu-Natal province of South Africa (30°03′ 29.44″ S; 30°52′ 38.53″ E) and were transported to a laboratory at the University KwaZulu-Natal [24]. Water hyacinth plants that were collected were of the same size (i.e., phenostage five) [25] as well as free of any biocontrol agents or biocontrol damage.…”

“…Water hyacinth plants that were collected were of the same size (i.e., phenostage five) [25] as well as free of any biocontrol agents or biocontrol damage. At the laboratory, individual circular plastic containers, 55 cm in diameter each, were filled with 20 L of water [24]. Thereafter, nitrogen 2…”

“…Commercial iron chelate (13% Fe) was also added to each container at a concentration of 11.2 mg Fe L −1 [27,28]. The nutrient medium was replaced on a weekly basis to maintain a constant nutrient concentration for plant growth and development [24]. Fifteen water hyacinth plants were placed in each container creating a dense mat within each container [24].…”

“…The nutrient medium was replaced on a weekly basis to maintain a constant nutrient concentration for plant growth and development [24]. Fifteen water hyacinth plants were placed in each container creating a dense mat within each container [24]. Water hyacinth plants were then acclimated to the surrounding environment for one week prior to weevil exposure [29].…”

“…Water hyacinth (Eichhornia crassipes) is an exotic macrophyte that is typically controlled by two host-specific weevil species, the chevroned water hyacinth weevil (Neochetina bruchi) and the mottled water hyacinth weevil (Neochetina eichhorniae) [21][22][23]. To establish the efficacy of biocontrol agents, variable infestation levels can be monitored using hyperspectral remote sensing [24]. However, remotely detecting low infestation levels is a challenge because water hyacinth plants occur in an aquatic environment that is influenced by noise from a range of different sources, the effect of which may mask the detection of low infestation levels.…”