LANDSAT/IKONOS Applied to Water Quality Monitoring in Southof Portugal

摘要

Alentejo (South of Portugal) water reservoirs have, due to many factors, more probability of suffering eutrophication problems, which makes essential continuous monitoring. These water reservoirs are also one of the main water sources supply for population. A preliminary study concerning the project "LANDSAT / IKONOS Applied to Water Quality Monitoring (LTWQ)" is presented. It aims to develop a water quality monitoring system based on advanced remote sen sing techniques for inland water reservoirs,using LANDSAT and IKONOS imagery. In order to determine the trophic state for Alentejo and Algarve most important drinking water reservoirs, we used the empirical approach developed by Palrneirim and Mariano and estimated Carlson Trophic State Index from chlorophyll and transparency values. This was related with field surveys data. This model was applied to Roxo, Monte Novo, Caia, Vigia, Alvito, Divor and Santa Clara water reservoirs using Landsat 5 TM (year 1997). IKONOS data have four multispectral bands similar to Landsat TM bands 1-4 and high spatial resolution (4 m multispectral and 1 m panchromatic), which is potentially well suited for assessment of small lakes, such as Alentejo water reservoirs.