Evlyn Márcia Leão de Moraes Novo

National Institute for Space Research, Brazil | inpe · Remote Sensing Division

In 2023, an intense drought impacted the Amazon basin triggered by climate change and a strong El Niño event, with the Negro River reaching its lowest water level in 120 years. However, the spatiotemporal open water extent (OWE) during this drought remains unclear. This study comprehensively evaluates OWE variability in the central Amazon using Sen...

Secchi Disk Depth (Z sd) is one of the most fundamental and widely used water-quality indicators quantifiable via optical remote sensing. Despite decades of research, development, and demonstrations, currently, there is no operational model that enables the retrieval of Z sd from the rich archive of Landsat, the long-standing civilian Earth-observa...

Water transparency is an important water quality measurement as a proxy to the amount of suspended and dissolved constituents in the water. In the Amazon basin, the water bodies are mainly controlled by annual flooding pulse, which drives the suspended sediments and phytoplankton dynamics in white, organic matter in black waters, and phytoplankton...

Hydrological Connectivity (HC) of small floodplain lakes is rarely investigated using remote sensing techniques. This paper explores the application of planet mosaics to estimate the HC between the middle Juruá River and its floodplain lakes. Remote Sensing features from 41 floodplain lakes and related main river reaches were provided by a time ser...

The Amazon várzea is a vast ecosystem that plays a critical social and economic role in the Amazon. The várzea is a complex environment composed of different vegetation types ranging from very dense flooded forests to grasslands. Moreover, vegetation features are affected by the Amazon basin rivers' flood pulse. That complexity makes it challenging...

The development of algorithms for remote sensing of water quality (RSWQ) requires a large amount of in situ data to account for the bio-geo-optical diversity of inland and coastal waters. The GLObal Reflectance community dataset for Imaging and optical sensing of Aquatic environments (GLORIA) includes 7,572 curated hyperspectral remote sensing refl...

Satellite remote sensing data have been used for water quality mapping, but accurate water reflectance retrieval is dependent on multiple procedures, such as atmospheric and adjacency corrections. For the latter, physical-based methods are used to minimize the adjacency effects caused by neighboring land targets close to water pixels, and implement...

The Amazon Basin is the largest on the planet, and its aquatic ecosystems affect and are affected by the Earth’s processes. Specifically, Amazon aquatic ecosystems have been subjected to severe anthropogenic impacts due to deforestation, mining, dam construction, and widespread agribusiness expansion. Therefore, the monitoring of these impacts has...

Secchi Disk Depth (Zsd) is one of the widely used water quality measurements. Controlled by variations in Optically Active Constituents, it is a key index of overall water quality. In-situ measurements of Zsd lacks spatiotemporal coverage which could be solved using remote sensing data, such as from the Sentinel-2/MSI. However, inland waters have h...

Este trabalho faz uma análise exploratória da ocorrência de floração de algas no reservatório de Ibitinga/SP por meio do uso da classificação contínua fuzzy. A função de pertinência linear fuzzy foi aplicada a uma série histórica de imagens do MSI/Sentinel-2 (entre dezembro/2018 e junho/2020) contendo os valores do índice espectral Normalized Diffe...

As the largest river basin on Earth, the Amazon is of major importance to the world's climate and water resources. Over the past decades, advances in satellite‐based remote sensing (RS) have brought our understanding of its terrestrial water cycle and the associated hydrological processes to a new era. Here, we review major studies and the various...

The composition of phytoplankton and the concentration of pigments in their cells make their absorption and specific absorption coefficients key parameters for bio-optical modeling. This study investigated whether the multispectral vertical diffuse attenuation coefficient of downward irradiance (Kd) gradients could be a good framework for accessing...

River meander migration is a process that maintains biodiverse riparian ecosystems by producing highly sinuous rivers, and oxbow lakes. However, although the floodplains support communities with fish and other practices in the region, meandering rivers can directly affect the life of local communities. For example, erosion of river banks promotes t...

Due to increasing algae bloom occurrence and water degradation on a global scale, there is a demand for water quality monitoring systems based on remote sensing imagery. This paper describes the scientific, theoretical, and methodological background for creating a cloud-computing interface on Google Earth Engine (GEE) which allows end-users to acce...

Optical Water Type (OWT) is a useful parameter for assessing water quality changes related to different turbidity levels, trophic state and colored dissolved organic matter (CDOM) while also helpful for tuning chlorophyll-a algorithms. For this reason, interest in the satellite remote sensing of OWTs has recently increased in recent years. This stu...

Lake surface warming and thermal responses to climate change have been widely reported, especially in temperate regions. Evidence of reservoir response in low latitudes is still limited. In this study, the vertical profile of water temperature in the Barra Bonita Reservoir (Brazil) is simulated using the one-dimensional General Lake Model (GLM), ca...

Given the importance of dissolved organic matter (DOM) in the carbon cycling of aquatic ecosystems, information on its seasonal variability is crucial. In this study we assess the use of optical absorption indices available in the literature based on in situ data to both characterize the seasonal variability of DOM in a highly complex environment a...

The modeling of underwater light field is essential for the understanding of biogeochemical processes, such as photosynthesis, carbon fluxes, and sediment transports in inland waters. Water-column light attenuation can be quantified by the diffuse attenuation coefficient of the downwelling irradiance (K d) using semi-analytical algorithms (SAA). Ho...

The scarcity of long time-series of water temperature for tropical reservoirs, usually available at a low frequency of measurements, represents a serious constraint for the understanding of their thermal behavior. Hydrodynamic models become a powerful tool for that understanding through a qualitative approach. In this study, the onedimensional Gene...

The diffuse attenuation coefficient of downwelling irradiance (K d) is an essential parameter for inland waters research by remotely sensing the water transparency. Lately, K d semi-analytical algorithms substituted the empirical algorithms widely employed. The purpose of this research was to reparametrize a semi-analytical algorithm to estimate K...

The scarcity of long time-series of water temperature for tropical reservoirs, usually available at a low frequency of measurements, represents a serious constraint for the understanding of their thermal behavior. Hydrodynamic models become a powerful tool for that understanding through a qualitative approach. In this study, the one-dimensional Gen...

Optical water types (OWTs) can represent diverse ranges of Chlorophyll-a (Chl-a), total suspended matter (TSM), and colored dissolved organic matter (CDOM) concentrations, which make them extremely useful for monitoring water quality, for example, detecting eutrophic conditions or tuning remote sensing algorithms. In this study, the objective is to...

Nanosatellites and CubeSats were first developed for educational purposes. However, their low cost and short development cycle made nanosatellite constellations an affordable option for observing the Earth by remote sensing, increasing the frequency of high-resolution imagery, which is fundamental for studying and monitoring dynamic processes. In t...

Remote sensing plays an important role in the monitoring of inland waters. Recently, Cubesats have become an alternative data source for studies that require high spatiotemporal resolutions. However, the radiometric quality of those data was never evaluated for inland water studies. This letter presents the experimental results to assess the qualit...

The objective of this study was to analyze the seasonal changes in the flood duration in the Curuai Lake, in response to the extreme droughts occurring in the past two decades. The Aqua MODIS sensor was applied to map flood duration impact on open waters of Curuai Lake floodplains, from 2002 to 2017. For that, year-round permanent open water areas...

Full text available in https://link.springer.com/article/10.1007/s10113-019-01513-8 or https://rdcu.be/bFp8k. --------------- Land use/land cover change (LUCC) combined with gold mining activity (GMA) have reportedly affected the water quality of Amazonian rivers by intensifying surface soil erosion and increasing rivers’ sediment concentration (SC...

Given the importance of DOM in the carbon cycling of aquatic ecosystems, information on its seasonal variability is crucial. This study assesses the use of available absorption optical indices based on in situ data to both characterize the seasonal variability of the DOM dynamics in a highly complex environment and their viability of being used for...

--------------- Full text available in https://link.springer.com/article/10.1007/s10113-019-01513-8 or https://rdcu.be/bFp8k. --------------- Land use/land cover change (LUCC) combined with gold mining activity (GMA) have reportedly affected the water quality of Amazonian rivers by intensifying surface soil erosion and increasing rivers’ sediment c...

Remote sensing imagery are fundamental to increasing the knowledge about sediment dynamics in the middle-lower Amazon floodplains. Moreover, they can help to understand both how climate change and how land use and land cover changes impact the sediment exchange between the Amazon River and floodplain lakes in this important and complex ecosystem. T...

Crocodilians usually remain inside or near their nests during most vulnerable life stages (as eggs, neonates and reproductive females). Thus, protection of nesting sites is one of the most appropriate conservation actions for these species. Nesting sites are often found across areas with difficult access, making remote sensing a valuable tool used...

Imagens do sensor Sentinel-2/MSI, lançado em 2015, apresentam características promissoras para o monitoramento da qualidade d'água. Este estudo teve como objetivo desenvolver um modelo empírico que permitisse estimar as concentrações de sólidos totais suspensos (TSS) em superfície, nos rios Paraná, Paranapanema e Tietê, a partir de imagens do senso...

A gestão eficiente de recursos hídricos depende da qualidade da representatividade espacial e temporal dos dados de precipitação. O objetivo deste estudo foi realizar uma análise comparativa dos dados de precipitação provenientes da Tropical Rainfall Measuring Mission (TRMM) e do produto MERGE do Centro de Previsão do Tempo e Estudos Climáticos (CP...

O uso do sensoriamento remoto (SR) para estudo e monitoramento de sistemas aquáticos continentais pode ser conduzido de forma qualitativa ou quantitativa. Entretanto, a principal demanda é pela extração de informações quantitativas de parâmetros que permitam tanto uma descrição acurada e detalhada do estado tró co quanto dos processos físicos, quím...

Remote sensing (RS) images can improve the knowledge on the exchanges of sediment between the main rivers and floodplains as it provides a synoptic view of water bodies, at local and regional scales. The monitoring of total suspended solids (TSS) is important because the proportion of organic to inorganic particles varies in time and space and is l...

This article analyzes the process of forest cover depletion over the last 40 years at three landscapes distributed along the Amazon floodplain. To this end, we created multi-temporal forest cover maps based on time series of Landsat images, and then analyzed the forest cover dynamics through landscape metrics. Based on landscape analyzes and biblio...

After many years of illegal hunting and commercialization, the populations of the Black caiman (Melanosuchus niger) have been recovering during the last four decades due to the enforcement of a legislation that inhibits their international commercial-ization. Protecting nesting sites, in which vulnerable life forms (reproductive females, eggs, and...

We discuss the claim that the Amazon River has been subjected to a noticeable increase in suspended sediment transport (SST) in response to both climate and land-use changes. To study this, both satellite imagery and in situ data were compiled to produce a 32-year time series (1984–2016) of suspended sediment concentration. Both parametric and non-...

The aim of this study is to evaluate the potential of multifrequency and Full-polarimetric Synthetic Aperture Radar (SAR) data for retrieving both Above Ground Biomass (AGB) and Leaf Area Index (LAI) in the Amazon floodplain forest environment. Two specific questions were proposed: (a) Does multifrequency SAR data perform more efficiently than sing...

Although mining plays an important role for the economy of the Amazon, little is known about its attributes such as area, type, scale, and current status as well as socio/environmental impacts. Therefore, we first propose a low time-consuming and high detection accuracy method for mapping the current mining areas within 13 regions of the Brazilian...

Land cover changes (LCC) affect the water balance (WB), changing surface runoff (SurfQ), evapotranspiration (ET), groundwater (GW) regimes, and streamflow (Q). The Tapajós Basin (southeastern Amazon) has experienced LCC over the last 40 years, with increasing LCC rates projected for the near future. Several studies have addressed the effects of cli...

We determined the filtered tree species pool of Amazonian wetland forests, based on confirmed occurrence records, to better understand how tree diversity in wetland environments compares to tree diversity in the entire Amazon region. The tree species pool was determined using data from two main sources: 1) a compilation of published tree species li...

Reference list for reviewed tree species lists. (XLSX)

List of herbaria available on SpeciesLink that contributed with records. (XLSX)

Checklist of the Amazonian wetlands tree species pool. (XLSX)

Artisanal and Small-scale Gold Mining (ASGM) within the Amazon region has created several environmental impacts, such as mercury contamination and changes in water quality due to increased siltation. This paper describes the effects of water siltation on the underwater light environment of rivers under different levels of gold mining activities in...

Multiangle Implementation of Atmospheric Correction (MAIAC) is a new Moderate Resolution Imaging Spectroradiometer (MODIS) algorithm that combines time series approach and image processing to derive surface reflectance and atmosphere products, such as Aerosol Optical Depth (AOD) and Columnar Water Vapor (CWV). The quality assessment of MAIAC AOD at...

Atmospheric correction is a crucial procedure to derive physical parameters from satellite images. Since water reflectance is typically low, inland water studies require an efficient removal of the atmospheric signal for consistent estimates of water-leaving reflectance. In this paper, we contribute to the quality assessment of atmospheric correcti...

This paper aims on the investigation of well-established models to retrieve the backscattering slope (bbp ) from remote sensing images applied to a particular Amazon floodplain lake, named Curuai Lake. Lee, Carder e Arnone (2002) bbp model and its derivation, Pan et al. (2015) model, were applied to measured Remote Sensing Reflectance and retrieved...

Satellite images are recognized as a data source for the monitoring of inland waters. Amazon Rivers have a seasonal dynamic influenced by the Amazon flood pulse. In this context, WFI/CBERS-4 sensor benefits the observation of Amazon due to high frequency acquisition (5 days) and wide swath (866 km) that contributes to overcome limitations of high c...

Satellite data provide the only viable means for extensive monitoring of remote and large freshwater systems, such as the Amazon floodplain lakes. However, an accurate atmospheric correction is required to retrieve water constituents based on surface water reflectance (R W). In this paper, we assessed three atmospheric correction methods (Second Si...

Estimates of light availability in the water column require accurate quantification at different depths of the diffuse attenuation coefficient (K d). This study examines spatial and seasonal variability of K d derived variables [euphotic zone depth (Z eu), attenuation depth (Z att)], their relationship with optically active constituents (OACs), and...

This article analyzes the process of forest fragmentation of a floodplain landscape of the Lower Amazon over a 30-year period and its implications for the biodiversity and the provision of ecosystem services to the riverine population. To this end, we created a multi-temporal forest cover map based on Landsat images, and then analyzed the fragmenta...

Nowadays, the monitoring of water is essential for the sustainability and better management of water resources. The use of remote sensing data is important, since it allows evaluation of dynamic problems in aquatic systems, such as the eutrophication of bodies of water and suspended sediment. The aim of this study was to estimate chlorophyll-a conc...

An innovative remote sensing approach that combines land-use change and water quality information is proposed in order to investigate if Artisanal and Small-scale Gold Mining (ASGM) area extension is associated with water siltation in the Tapajós River Basin (Brazil), containing the largest small-scale gold mining district in the world. Taking adva...

A produção e transporte de sedimentos suspensos são importantes processos geomorfológicos atuantes nos sistemas fluviais amazônicos, especialmente nos denominados Rios Amazônicos de Águas Brancas (RAAB). O estudo sintetizado neste artigo foca na representação e compreensão das variações espaciais do transporte de sedimentos desses rios. Este trabal...

Satellite images are an effective tool for the detection of phytoplankton blooms, since they cause striking changes in water color. Bloom intensity can be expressed in terms of chlorophyll-a concentration. Previous studies suggest the use of Landsat TM4/TM3 reflectance ratio to retrieve surface chlorophyll-a concentration from aquatic systems. In t...