Work

Albufera Lagoon Ecological State Study Through the Temporal Analysis Tools Developed with PerúSAT-1 Satellite

Year: 2025

Type: article

Abstract: Anthropogenic pressures and impacts can alter the functions of coastal wetlands compromising their uses. Remote sensing is presented as a potential tool for monitoring ecological quality in a frequent and continuous manner over time. The Albufera of Valencia (Spain) is a representative case of pressure on water quality, which caused the hypertrophic state of the lake. PerúSAT-1 is the first Peruvian remote sensing satellite with multispectral bands (2.8 meters of spatial resolution), and a panchromatic band (0.7 meters of spatial resolution). The great spatial resolution makes it an ideal sensor for capturing highly detailed products useful for different applications. The main objective of this study is to assess the potential of PerúSAT-1's multispectral images to generate maps of different parameters in order to evaluate the ecological state of the Albufera lagoon. With a proper atmospheric correction, combining field and satellite data, we have developed algorithms that can estimate the optical properties of water. During 5 field campaigns samples were took and measurements of ecological indicators as chlorophyll-a, Secchi disk depth, total suspended matter and its organical-inorganical fraction were made. All possible combinations of two bands were obtained, which were later correlated with the biophysical variables by fitting a linear regression between the field data and the band combinations. Equations for estimating all the water variables result in a R2 of 0.76 for the Chl-a, 0.75 for the SDD, 0.84 for the TSM, 0.76 for the inorganic fraction and 0.87 for the organic. Finally, the equations were applied to the Albufera lagoon images to obtain thematic maps for all variables.

Source: Sensors

DOI: 10.3390/s25041103