A Multivariate Analysis Framework to Detect Key Environmental Factors Affecting Spatiotemporal Variability of Chlorophyll-a in a Tropical Productive Estuarine-Lagoon System

Abstract

Here, we demonstrate how a combination of three multivariate statistic techniques can identify key environmental factors affecting the seasonal and spatial variability of chlorophyll-a (Chl-a) in a productive tropical estuarine-lagoon system. Remote estimation of Chl-a was carried out using a NIR-Red model based on MODIS bands, which is highly consistent with the in situ measurement of Chl-a with root mean square error (RMSE) of 15.24 mg m −3 and 13.43 mg m −3 for two independent datasets used for the model's calibration and validation, respectively. Our findings suggest that the river discharges and hydraulic residence time of the lagoons promote a stronger effect on the spatial variability of Chl-a in the coastal lagoons, while wind, solar radiation and temperature have a secondary importance. The results also indicate a slight seasonal variability of Chl-a in Mundaú lagoon, which are different the from Manguaba lagoon. The multivariate approach was able to fully understand the relative importance of key environmental factors on the spatiotemporal variability of Chl-a of the aquatic ecosystem, providing a powerful tool for reducing dimensionality and analyzing large amounts of satellite-derived Chl-a data.

Evidence of protective effects on aquifer recharge from polluted tropical rivers: An analysis of hyporheic meiofauna and sediments

“…In the matter of degradation of chlorophyll-a, it may present absorbance similar to that observed in viable chlorophyll, which can generate reading errors. This high variance, however, is commonly observed in other chlorophyll-a studies using other methods in marine (Yaconi, 2006) and estuarine environments (Lins et al, 2018). A large number of studies in marine and estuarine contexts has shown that microphytobenthos are sensitive to environmental changes, because they obey daily rhythms of vertical migration, moving to the surface at low tide and descending at high tide (J. D. Palmer & Round, 1965;Round, 1979).…”

Seasonal variations in residence time and water age in the Mundaú-Manguaba Estuarine Lagoon System, AL (Brazil)

“…The positive correlation between areas that have higher WA and more critical trophic states can also be established from the study by Lins et al (2018). In this, the authors employed remote sensing techniques, together with measured reflectance and chlorophyll a data, to estimate the spatial-temporal variability of chlorophyll a, as well as the trophic state of MMELS, in the period of 2002 to 2016.…”

Modeling the Responses of Dissolved Oxygen and Nitrate Concentrations due to Land Use and Land Cover Change Scenarios in a Large Subtropical Reservoir

“…The results of coupling hydrological models and aquatic ecosystems, such as hydrodynamic models (Munar et al, 2018(Munar et al, , 2019 have highlighted their potential as management tools to understand and predict actions that cause future impacts on aquatic ecosystems. Remote sensing techniques applied to limnology studies have also been expanded to simulate watershed features and likely LULC changes over the years (Curtarelli et al, 2015;Lins et al, 2018;Ma et al, 2016).…”