Publicações

@article{Alcântara2017a,
title = {Modeling the spatio-temporal dissolved organic carbon concentration in Barra Bonita reservoir using OLI/Landsat-8 images},
author = {Enner Herenio de Alcântara and Nariane Marselhe Ribeiro Bernardo and Thanan Walesza Pequeno Rodrigues and Fernanda Sayuri Yoshino Watanabe},
doi = {10.1007/s40808-017-0275-2},
issn = {2363-6211},
year = {2017},
date = {2017-01-31},
journal = {Modeling Earth Systems and Environment},
volume = {3},
number = {1},
pages = {11},
abstract = {Through exchange of heat between the water and the atmosphere inland waters affect climate at the regional scale and play an important role in the global carbon cycle. Therefore, there is a need to develop methods and models for mapping inland water carbon content to understand the role of lakes in the global carbon cycle. The colored dissolved organic matter (CDOM) has a strong correlation with dissolved organic carbon (DOC) and can be studied using remote sensed images. In this work, we developed an empirical model to estimate the DOC concentration by using the absorption coefficient of CDOM (a CDOM). The a CDOM was estimated through band ratio index and validated with in situ data. The empirically adjusted model to estimate the DOC was applied to a series of OLI/Landsat-8 images. The results showed a good relationship between the a CDOM at 412 nm (a CDOM412) and the ratio between OLI band 1 and OLI band 3, but the validation results showed a normalized root mean square error (NRMSE) of about 37.89%. The a CDOM412 obtained in laboratory was used to establish a relationship between a CDOM412 and DOC. The DOC spatial distribution was then obtained and the concentration varied from 22 to 52 mg.l-1 during the year of 2014.},
keywords = {Barra Bonita, dissolved organic carbon, landsat, reservoir, spatio-temporal},
pubstate = {published},
tppubtype = {article}
}

@article{RODRIGUES2017213,
title = {Retrieval of Secchi disk depth from a reservoir using a semi-analytical scheme},
author = {Thanan Walesza Pequeno Rodrigues and Enner Herenio de Alcântara and Fernanda Sayuri Yoshino Watanabe and Nilton Nobuhiro Imai},
doi = {10.1016/j.rse.2017.06.018},
issn = {0034-4257},
year = {2017},
date = {2017-01-01},
journal = {Remote Sensing of Environment},
volume = {198},
pages = {213--228},
abstract = {The mechanistic model reported in Lee et al. (2015) estimating the Secchi disk depth (ZSD) was applied to an oligo- to mesotrophic reservoir in Brazil. The model was originally validated with data covering lake, oceanic, and coastal waters; however, the model used the quasi-analytical algorithm (QAA) designed for optically deep waters as input and was applied to oceanic and coastal waters to derive absorption [a] and backscattering [bb] coefficients. The hypothesis is that the use of QAAv5 (http://www.ioccg.org/groups/Software_OCA/QAA_v5.pdf) to estimate both a and bb (step M1) to retrieve Kd (step M2) and ZSD (step M3) will lead to errors caused by M1 preventing an accurate estimate in oligo- to mesotrophic water. To test this hypothesis, data collected in three field trips were used to apply the mechanistic model based on the spectral bands from OLI/Landsat-8, (often applied to oceanic and coastal waters), and multispectral instrument (MSI)/Sentinel-2 bands (applied to QAA designed for very turbid inland water). The impact of step M1 over steps M2 and M3 was analyzed by the error analysis. The mean absolute percentage error (MAPE) for Kd using QAAv5 ranged between 10.35},
keywords = {algorithm, reservoir, Secchi disk, semi-analytical},
pubstate = {published},
tppubtype = {article}
}

@article{Martins2016,
title = {Support Vector Machine algorithm optimal parameterization for change detection mapping in Funil Hydroelectric Reservoir (Rio de Janeiro State, Brazil)},
author = {Sarah Cristina Araujo Martins and Nariane Marselhe Ribeiro Bernardo and Igor Ogashawara and Enner Herenio de Alcântara},
doi = {10.1007/s40808-016-0190-y},
issn = {2363-6211},
year = {2016},
date = {2016-07-21},
journal = {Modeling Earth Systems and Environment},
volume = {2},
number = {3},
pages = {138},
abstract = {Change detection in Land Use and Land Cover (LULC) using Support Vector Machines (SVM) to mapping a geographic area is a way that has been studded and improved because of its advantages as low costs in terms of computing, field research and staff team. To use SVM, it is needed firstly to define the most efficient function to be used (linear, polynomial, and radial base function---RBF) and secondly to establish the most appropriate input parameters of them, based on the study area, which was the main challenge of using SVM algorithm. The main goal of this work was to test the performance of polynomial function and RBF, and to identify which input parameters combination are the best to use SVM algorithm for Funil Hydroelectric Reservoir (FHR) sub-watershed LULC mapping, using TM/Landsat-5 time-series images. After several tests and based on the obtained results, the RBF was identified as the best SVM's function, which was used to classify the time-series images. The referred SVM function has the following parameters to be defined: the error tolerance (ξ or C), the pyramid depths (P), the radial basis function parameter (γ), and the threshold. The most effective combination of input parameters to RBF was C = 100; P = 2, γ = 0.1},
keywords = {algorithm, change detection, Funil, parametrization, reservoir, Rio de Janeiro, Support vector machine, SVM},
pubstate = {published},
tppubtype = {article}
}

@article{Watanabe2016,
title = {Drought can cause phytoplankton growth intensification in Barra Bonita reservoir},
author = {Fernanda Sayuri Yoshino Watanabe and Thanan Walesza Pequeno Rodrigues and Nariane Marselhe Ribeiro Bernardo and Enner Herenio de Alcântara and Nilton Nobuhiro Imai},
doi = {10.1007/s40808-016-0193-8},
issn = {2363-6211},
year = {2016},
date = {2016-07-20},
journal = {Modeling Earth Systems and Environment},
volume = {2},
number = {3},
pages = {134},
abstract = {In this research, we investigated the possible consequences of the 2012--2014 drought in Southeastern Brazil on growing phytoplankton in a eutrophic reservoir. Weather has direct influence to phytoplankton communities and, consequently, underwater light climate which drives important processes in aquatic systems. Absorption coefficient of phytoplankton pigment (a ϕ) and chlorophyll-a (Chl-a) concentration were determined in laboratory in order to analyze the interference of phytoplankton biomass over light. In addition, a historical monthly rainfall series in the reservoir was analyzed. Results showed clearly the strong drought effect over the monthly useful volume and flow rate. Both of them play important roles to water column mixing and retention time which increase the nutrients availability in the system and phytoplankton biomass. Chl-a concentration and a phy values were extremely high [maximum Chl-a of 797.8 mg m-3 and a ϕ(440) of almost 6 m-1 in October]. So, more attention should be paid to water quality in long episodes of drought as occurred from 2012 to 2014.},
keywords = {Barra Bonita, Drought, grouwth, phytoplankton, reservoir},
pubstate = {published},
tppubtype = {article}
}

@article{Alcântara2016b,
title = {An investigation into the particle volume scattering function variability in a cascading reservoir system},
author = {Enner Herenio de Alcântara and Thanan Walesza Pequeno Rodrigues and Fernanda Sayuri Yoshino Watanabe and Nariane Marselhe Ribeiro Bernardo},
doi = {10.1007/s40808-016-0149-z},
issn = {2363-6211},
year = {2016},
date = {2016-06-08},
journal = {Modeling Earth Systems and Environment},
volume = {2},
number = {2},
pages = {89},
abstract = {This work analyzed the spectral and spatial distribution of the particle volume scattering function, βp, in a cascading reservoir system. During fieldworks water quality parameters and scattering data were sampled in a predetermined stations. The βp was estimated using the ECO-BB9 equipment that measures the volume scattering function, β at 117 [β(117)]. The estimated βp(117) were compared with the remote sensing reflectance, Rrs, and the chlorophyll-a (Chl-a) concentration, total suspended matter (TSM) concentration and the transparency (measured using a Secch disk). The results showed that in a hypertrophic environment the βp is dominated by the phytoplankton scattering and in an oligotrophic water system, the scattering by a suspended matter dominates. The βp(117) variability from a hypertrophic to an oligotrophic aquatic system affects the remote sensing reflectance (R rs) spectral shape. Due to this, the parametrization of a unique bio-optical model to estimate the optically active components in the water will be challenging.},
keywords = {cascading, particle, reservoir, volume scattering function, vsf},
pubstate = {published},
tppubtype = {article}
}

@article{RodriguesT2016,
title = {Spatial and temporal variations of the inherent optical properties in a tropical cascading reservoir system},
author = {Thanan Walesza Pequeno Rodrigues and Enner Herenio de Alcântara and Fernanda Sayuri Yoshino Watanabe and Nariane Marselhe Ribeiro Bernardo and Luiz Henrique da Silva Rotta and Nilton Nobuhiro Imai},
doi = {10.1007/s40808-016-0144-4},
issn = {2363-6211},
year = {2016},
date = {2016-06-07},
journal = {Modeling Earth Systems and Environment},
volume = {2},
number = {2},
pages = {86},
abstract = {In order to verify the effect of a cascade system in the water quality of two tropical reservoirs in Brazil, this work proposed to make use of the inherent optical properties (IOPs) as well as the specific inherent optical properties (SIOPs). From upstream to downstream, Barra Bonita (BB) is the first in a set of six reservoirs along Tietê River and Nova Avanhandava (Nav) is the fifth reservoir. BB is eutrophic whilst Nav is an oligotrophic environment. According to the IOP and SIOP analysis, it was possible to attest that BB was organic matter dominated and Nav was inorganic matter. These differences are noticeable in bio-optical modeling, must be considered different approaches to retrieve water quality parameters in both sites, once, the models take into account the specific information about the IOP and their relation with the optically active components (OACs) concentration. In addition, the results of this paper can provide comparable data to other water systems and improve the comprehension about the optical properties of complex water bodies.},
keywords = {cascading, inherent optical properties, reservoir, spatial, temporal, tropical},
pubstate = {published},
tppubtype = {article}
}

@article{Alcântara2016a,
title = {The variability of particle backscattering coefficient in an oligo-to-hypertrophic cascading reservoir system: implications to TSM bio-optical model development},
author = {Enner Herenio de Alcântara and Fernanda Sayuri Yoshino Watanabe and Nariane Marselhe Ribeiro Bernardo and Thanan Walesza Pequeno Rodrigues},
doi = {10.1007/s40808-016-0146-2},
issn = {2363-6211},
year = {2016},
date = {2016-06-06},
journal = {Modeling Earth Systems and Environment},
volume = {2},
number = {2},
pages = {84},
abstract = {The particle backscattering coefficient (b bp ) has been obtained either by equipment or semi-analytically based on relations between b bp and the remote sensing reflectance (R rs ). Correlation between b bp and R rs can be significantly high allowing the development of bio-optical model to estimate the total suspended matter concentration [TSM] on water surface from satellite images. The development of such model to monitor cascading reservoir systems can be challenging since this type of water resources changes their biogeochemical composition from upstream to downstream; the water in such system can range from hypertrophic to oligotrophic state. The scientific question raised in this letter is that: in an oligo-to-hypertrophic water system the models based on b bp will keep their good agreement or the influence of organic matter (e.g. chlorophyll-a) can affect this relationship? The aim of this letter was to analyze the b bp variability in a cascading reservoir system and search for empirical models that can capture the relationship between the b bp and [TSM]. The results showed that there are not only differences in the biogeochemical concentrations but also in the b bp from upstream to downstream. In addition there is an influence of chlorophyll-a concentration [Chl-a] on the relationship between b bp and [TSM] which prevents the bio-optical model development.},
keywords = {algorithm, backscattering, bio-optical, cascading, coefficient, hypertrophic, model, oligotrophic, particle, reservoir, total suspended matter, TSM},
pubstate = {published},
tppubtype = {article}
}

@article{RODRIGUES2016,
title = {DELINEAMENTO AMOSTRAL EM RESERVATÓRIOS UTILIZANDO IMAGENS LANDSAT-8/OLI: UM ESTUDO DE CASO NO RESERVATÓRIO DE NOVA AVANHANDAVA (ESTADO DE SÃO PAULO, BRASIL)},
author = {Thanan Walesza Pequeno Rodrigues and Ulisses Silva Guimarães and Luiz Henrique da Silva Rotta and Fernanda Sayuri Yoshino Watanabe and Enner Herenio de Alcântara and Nilton Nobuhiro Imai},
issn = {1982-2170},
year = {2016},
date = {2016-06-01},
journal = {Boletim de Cià GeodÃ},
volume = {22},
pages = {303--323},
publisher = {scielo},
keywords = {delineamento amostral, imagens, landsat, nova avanhadava, reservoir, São Paulo},
pubstate = {published},
tppubtype = {article}
}

@article{doi:10.1080/2150704X.2016.1185189,
title = {An investigation into the phytoplankton package effect on the chlorophyll-a specific absorption coefficient in Barra Bonita reservoir, Brazil},
author = {Enner Herenio de Alcântara and Fernanda Sayuri Yoshino Watanabe and Thanan Walesza Pequeno Rodrigues and Nariane Marselhe Ribeiro Bernardo},
doi = {10.1080/2150704X.2016.1185189},
year = {2016},
date = {2016-01-01},
journal = {Remote Sensing Letters},
volume = {7},
number = {8},
pages = {761--770},
abstract = {ABSTRACTIn this article, a possible phytoplankton package effect on the chlorophyll-a specific absorption coefficient (a*phy) is investigated. Two fieldworks were conducted in May and October 2014 in Barra Bonita (BB) reservoir. During the fieldworks, radiometric and water samples were obtained. From the radiometric data, the remote sensing reflectance (Rrs) were calculated and from the water samples the chlorophyll-a (chl-a) concentration, the phytoplankton absorption coefficient (aphy) and a*phy coefficient were obtained. The results show that for the first fieldwork (in May), the package effect was less perceived than in the second fieldwork (in October). In May, the package effect was more pronounced for the highest chl-a concentration (>200 mg m-3) and for October all samples ranging from 263.20 to 797.80 mg m-3 were effected. Due to this effect, the bio-optical model development in order to estimate the chl-a concentration in a eutrophic environment such as the BB reservoir will face higher errors when the chl-a concentration were higher than 300 mg m-3.},
keywords = {absorption, Barra Bonita, clorophyl, package, phytoplankton, reservoir},
pubstate = {published},
tppubtype = {article}
}

@article{ROTTA2016158,
title = {Atmospheric correction assessment of SPOT-6 image and its influence on models to estimate water column transparency in tropical reservoir},
author = {Luiz Henrique da Silva Rotta and Enner Herenio de Alcântara and Fernanda Sayuri Yoshino Watanabe and Thanan Walesza Pequeno Rodrigues and Nilton Nobuhiro Imai},
doi = {10.1016/j.rsase.2016.09.001},
issn = {2352-9385},
year = {2016},
date = {2016-01-01},
journal = {Remote Sensing Applications: Society and Environment},
volume = {4},
pages = {158--166},
abstract = {Remote sensing images have been increasingly used by its ability to collect data from extensive areas in a short time and with relatively low cost. Studies conducted in aquatic environments require great attention in relation to atmospheric correction, since the signal leaving water bodies is strongly attenuated. The present work aimed to assess the atmospheric correction of SPOT-6 image based on the variation of initial visibility parameter in FLAASH and analyze its influence on models to estimate Secchi depth (SD) and diffuse attenuation coefficient (Kd). The study was carried out in Nova Avanhandava Reservoir, which belongs to the chain of the Tietê River reservoirs (São Paulo, Brazil). The models calibration was based on remote sensing reflectance (Rrs) of simulated SPOT bands from data collected in the field. The best models were obtained using the band ratio Rrs(560nm)/Rrs(660nm) for SD (R2=92},
keywords = {algorithm, atmospheric correction, imagens, models, reservoir, spot, transparency, tropical reservoir, water column},
pubstate = {published},
tppubtype = {article}
}

@article{CURTARELLI2016676,
title = {Carbon dioxide emissions from Tucuruí reservoir (Amazon biome): New findings based on three-dimensional ecological model simulations},
author = {Marcelo Pedroso Curtarelli and Igor Ogashawara and Carlos Alberto Sampaio de Araújo and João Antônio Lorenzzetti and Joaquim Antônio Dionísio Leão and Enner Herenio de Alcântara and José Luiz Stech},
doi = {10.1016/j.scitotenv.2016.02.001},
issn = {0048-9697},
year = {2016},
date = {2016-01-01},
journal = {Science of The Total Environment},
volume = {551},
pages = {676--694},
abstract = {We used a three-dimensional model to assess the dynamics of diffusive carbon dioxide flux (FCO2) from a hydroelectric reservoir located at Amazon rainforest. Our results showed that for the studied periods (2013 summer/wet and winter/dry seasons) the surface averaged FCO2 presented similar behaviors, with regular emissions peaks. The mean daily surface averaged FCO2 showed no significant difference between the seasons (p>0.01), with values around -1338mgCm-2day-1 (summer/wet) and -1395mgCm-2day-1 (winter/dry). At diel scale, the FCO2 was large during the night and morning and low during the afternoon in both seasons. Regarding its spatial distribution, the FCO2 showed to be more heterogeneous during the summer/wet than during the winter/dry season. The highest FCO2 were observed at transition zone (-300mgCm-2h-1) during summer and at littoral zone (-55mgCm-2h-1) during the winter. The total CO2 emitted by the reservoir along 2013year was estimated to be 1.1TgCyear-1. By extrapolating our results we found that the total carbon emitted by all Amazonian reservoirs can be around 7TgCyear-1, which is 22},
keywords = {amazon, carbon dioxide, emissions, model, reservoir, simulations, tucuruí},
pubstate = {published},
tppubtype = {article}
}

@article{rodrigues2016comparaccao,
title = {COMPARAÇÃO ENTRE MÉTODOS EMPÍRICOS PARA ESTIMATIVA DA CONCENTRAÇÃO DE CLOROFILA-A EM RESERVATÓRIOS EM CASCATA (RIO TIETÊ, SÃO PAULO)},
author = {Thanan Walesza Pequeno Rodrigues and Enner Herenio de Alcântara and Fernanda Sayuri Yoshino Watanabe and Luiz Henrique da Silva Rotta and Nilton Nobuhiro Imai and Marcelo Pedroso Curtarelli and Cláudio Clemente Faria Barbosa},
year = {2016},
date = {2016-01-01},
journal = {Revista Brasileira de Cartografia},
volume = {68},
number = {1},
keywords = {cascading, clorophyl, concentration, empíricos, reservoir, São Paulo, Tietê},
pubstate = {published},
tppubtype = {article}
}

@article{Alcantara2016,
title = {Estimating total suspended matter using the particle backscattering coefficient: results from the Itumbiara hydroelectric reservoir (Goiás State, Brazil)},
author = {Enner Herenio de Alcântara and Marcelo Curtarelli and José Stech},
doi = {10.1080/2150704X.2015.1137646},
year = {2016},
date = {2016-01-01},
journal = {Remote Sensing Letters},
volume = {7},
number = {4},
pages = {397--406},
abstract = {ABSTRACTIn this study, a quasi-analytical algorithm (QAA)-based model was parameterized using remote-sensing reflectance (Rrs, units in sr-1), total absorption coefficient (at) and total suspended matter (TSM) concentration. The model was based on the particle backscattering at 561 nm (bbp(561)) and was derived from the QAA and TSM concentration. The aim of this work was to parameterize a QAA-based model to estimate the TSM concentration using the Landsat-8 Operational Land Imager (OLI) sensor in the Itumbiara hydroelectric reservoir, Brazil. The results demonstrated that the calibrated model},
keywords = {backscattering, coefficient, Goiás, Itumbiara, particle, reservoir, total suspended matter, TSM},
pubstate = {published},
tppubtype = {article}
}

@article{BERNARDO201668,
title = {Evaluation of the suitability of MODIS, OLCI and OLI for mapping the distribution of total suspended matter in the Barra Bonita Reservoir (Tietê River, Brazil)},
author = {Nariane Marselhe Ribeiro Bernardo and Fernanda Sayuri Yoshino Watanabe and Thanan Walesza Pequeno Rodrigues and Enner Herenio de Alcântara},
doi = {10.1016/j.rsase.2016.06.002},
issn = {2352-9385},
year = {2016},
date = {2016-01-01},
journal = {Remote Sensing Applications: Society and Environment},
volume = {4},
pages = {68--82},
abstract = {The objective of this work was to evaluate the suitability of three remote sensors, namely, the Moderate Resolution Imaging Spectroradiometer (MODIS), the Operational Land Imager (OLI), and the Ocean Land Color Instrument (OLCI), for estimating total suspended matter (TSM) concentrations in the Barra Bonita reservoir. Although remote sensors have been widely explored for ocean and inland water applications in Brazilian reservoirs, a thorough comparison of sensors as a TSM monitoring tool has yet to be conducted. OLI data have been used for inland waters, but few studies on Brazilian aquatic systems have been performed. MODIS data were investigated due to their daily coverage, and OLCI data (scheduled for launch in December 2015) were analyzed because of their spatial (better than MODIS) and temporal (lower than OLI) resolution. In situ hyperspectral measurements were used as input to simulate MODIS, OLI and OLCI spectral bands while considering the spectral response function for each sensor. Simulated data and TSM concentrations were tuned to generate regional models using linear and non-linear regressions. The models were assessed using the coefficient of determination (R2), which had a range of between 0 keywords = {Barra Bonita, landsat, MODIS, OLCI, OLI, reservoir, sentinel, Tietê, total suspended matter, TSM},
pubstate = {published},
tppubtype = {article}
}