Spatial modeling to detect potential incidence zones of harmful algae blooms in Veracruz, Mexico

摘要

Harmful algae blooms (HABs) are proliferations of microscopic algae associated with rapid production of biomass and/or toxic substances. This production's accumulation may cause massive death of marine life and affect human health with devastating economic repercussions. Monitoring HABs usually involves precise but costly field sampling and laboratory analyses. Satellite images and some of its derived products such as the Fluorescence Line Height (FLH) have become cost-effective tools that have been proved useful for identification and monitor HABs at the Florida coast. In this study we used a spatially explicit modeling approach to identify potential incidence zones of HABs at Veracruz, Mexico. We relied on two sets of data: The first set consists of reports of HABs-related events published in both scientific journals and journalistic notes for the 2004 to 2015 period. The second set is comprised of FLH monthly products derived from the MODIS-Aqua satellite imagery for the same period. We conducted a retrospective analysis of monthly FLH values to analyze the spatial and temporal extent of potential HABs and compared them with published reports. It was noted that HABs events registered in literature for that period were identified with our spatial analysis, but most of the events identified as potential HABs with our analysis were not registered in literature. We conducted a "Hot- spots" analysis and identified four well-defined incidence zones for the entire coast of Veracruz state: the Port of Veracruz, Alvarado, Coatzacoalcos, and the Tamiahua Lagoon. Of the four zones, only the Port of Veracruz has been reported as an incidence zone for HABs events, while the other three have very few or no reports of HABs related events. We found this technique is accurate for HABs detection, as the analysis is based upon the local knowledge of harmful algae species.