scholarly journals Changes in floodplain hydrology following serial damming of the Tocantins River in the eastern Amazon

2021 ◽  
pp. 149494
Author(s):  
A. Christine Swanson ◽  
David Kaplan ◽  
Kok-Ben Toh ◽  
Elineide E. Marques ◽  
Stephanie A. Bohlman
Keyword(s):  
Tocantins River ◽  
Floodplain Hydrology

LBA-ECO LC-04 MACROHYDROLOGICAL ROUTING DATA FOR THE AMAZON AND TOCANTINS RIVER BASIN

2011 ◽  
Author(s):  
R.G. ANDRADE, ◽  
T.R. BUSTAMANTE, ◽  
M.T. COE, ◽  
M.H. COSTA, ◽  
C.H.C. OLIVEIRA, ◽  
...  
Keyword(s):  
River Basin ◽  
Tocantins River

scholarly journals Feeding ecology of stream-dwelling Characidae (Osteichthyes: Characiformes) from the upper Tocantins River, Brazil

2013 ◽  
Vol 30 (6) ◽  
pp. 645-651 ◽  
Author(s):  
Maíra Moraes ◽  
Carla Ferreira Rezende ◽  
Rosana Mazzoni
Keyword(s):  
Feeding Ecology ◽  
Tocantins River

scholarly journals Reproductive biology of Rhaphiodon vulpinus (Ostariophysi: Cynodontidae) in the Tocantins River Basin, Brazil

2007 ◽  
Vol 5 (4) ◽  
pp. 479-484 ◽  
Author(s):  
Andréa L. Neuberger ◽  
Elineide E. Marques ◽  
Carlos S. Agostinho ◽  
Rafael J. de Oliveira
Keyword(s):  
River Basin ◽  
Reproductive Biology ◽  
Mean Value ◽  
Reproductive Period ◽  
Total Weight ◽  
Individual Female ◽  
Relative Fecundity ◽  
Mean Diameter ◽  
Tocantins River ◽  
The Individual

In order to evaluate aspects of the reproductive biology of Rhaphiodon vulpinus in the Upper and Middle Tocantins River, samples were taken monthly from October, 1999 through September, 2001, by means of gill nets. Males, which were more abundant than females (chi2 146.87: df=1: p<0.05), matured at a smaller size. The reproductive period of the species extended essentially from November through January, with a peak of activity in November. Fecundity, with an estimated mean value of 98,185 oocytes, varied from 38,177 to 215,841 oocytes, and it did not correlate with the length of the individual female analyzed (r=0.4663: p=0.206). Relative fecundity was 130.6 oocytes/g total weight. Mature oocytes had a mean diameter of 0.98 mm, corresponding to a volume of 0.50 mm³.

scholarly journals Analysis of evapotranspiration and biomass in pastures with degradation indicatives in the Upper Tocantins River Basin, in Brazilian Savanna

Revista CERES ◽  
2016 ◽  
Vol 63 (6) ◽  
pp. 754-760 ◽  
Author(s):  
Ricardo Guimarães Andrade ◽  
Antônio Heriberto de Castro Teixeira ◽  
Janice Freitas Leivas ◽  
Sandra Furlan Nogueira
Keyword(s):  
River Basin ◽  
Large Scale ◽  
Meteorological Data ◽  
Simple Algorithm ◽  
Production Potential ◽  
Pasture Degradation ◽  
Ndvi Time Series ◽  
Tocantins River ◽  
Remote Sensing Techniques ◽  
Degraded Pastures

ABSTRACT The objective of this study was to apply the Simple Algorithm For Evapotranspiration Retrieving (SAFER) with MODIS images together with meteorological data to analyze evapotranspiration (ET) and biomass production (BIO) according to indicative classes of pasture degradation in Upper Tocantins River Basin. Indicative classes of degraded pastures were obtained from the NDVI time-series (2002-2012). To estimate ET and BIO in each class, MODIS images and data from meteorological stations of the year 2012 were used. The results show that compared to not-degraded pastures, ET and BIO were different in pastures with moderate to strong degradation, mainly during water stress period. Therefore, changes in energy balance partition may occur according to the degradation levels, considering that those indicatives of degradation processes were identified in 24% of the planted pasture areas. In this context, ET and BIO estimates using remote sensing techniques can be a reliable indicator of forage availability, and large-scale aspects related to the degradation of pastures. It is expected that this knowledge may contribute to initiatives of public policies aimed at controlling the loss of production potential of pasture areas in the Upper Tocantins River Basin in the state of Goiás, Brazil.

scholarly journals Hydrodynastes melanogigas Franco, Fernandes and Bentim, 2007 (Squamata: Serpentes: Colubridae): Range extension and new state record

Check List ◽  
2012 ◽  
Vol 8 (4) ◽  
pp. 813 ◽  
Author(s):  
Nelson Jorge Da Silva Jr. ◽  
Breno Hamdan ◽  
Itamar Jr. Tonial ◽  
Hélder Lúcio R. Da Silva ◽  
Carlos Eduardo D. Cintra
Keyword(s):  
Range Extension ◽  
Gallery Forests ◽  
Southwestern State ◽  
Tocantins River

Two specimens of the poorly known Colubridae snake Hydrodynastes melanogigas were collected in the municipality of Carolina, southwestern state of Maranhão in gallery forests on the Tocantins River. These records represent the northernmost locality for the species.

scholarly journals Fishery regulamentation or ethnoknowledge? The dilemma of the management of the mapará fisheries on the lower Tocantins river in northern Brazil

2021 ◽  
Vol 10 (11) ◽  
pp. e131101118963
Author(s):  
Esther Mirian Cardoso ◽  
Paulo Allison Costa da Mata ◽  
Matheus dos Santos Souza ◽  
Maria Clara Pinheiro de Souza ◽  
Victoria Isaac
Keyword(s):  
Socioeconomic Development ◽  
Economic Importance ◽  
Chi Square ◽  
Great Economic Importance ◽  
Chi Square Test ◽  
Northern Brazil ◽  
The Mean ◽  
Tocantins River ◽  
Student’S T ◽  
Student’S T Test

The fishery of mapará (Hypophthalmus marginatus) is of great economic importance in the Amazon region. Despite this, it is observed that the current norms of management disagree with the ethnoknowledge of fishermen of the Tocantins river. Therefore, there are many seizures and fines in the Tocantins Low region. This work appeared as a demand of the fishermen of the region and had as purpose to test the pertinence of the fishing legislation on the capture of the species and to provide subsidies for the adaptation of the norms to the local reality. For this, a mapará fishery was taken on the Pindobal Grande river, in the municipality of Igarapé-Miri, in the state of Pará. A sample of the captured individuals was collected, and identification, sexing and biometry were done. Fishing was described, and the sex ratio tested with the Chi-Square test and the mean length differences between the sexes with the Student's t-test. The results were compared with current legislation and literature data. The captured mapará individuals were mostly above 30 cm, as determined by legislation. It is concluded that, despite using a network that is prohibited, the capture of the species in the region acts selectively, due to the ethno-cognition and the fisherman's action ("taleiro"). Therefore, it is necessary that the legislation be revised, seeking the reconciliation between the conservation of ecosystems, the traditional knowledge and the socioeconomic development of the region.

scholarly journals A preliminary list of the Herpetofauna from termite mounds of the cerrado in the Upper Tocantins river valley

2009 ◽  
Vol 49 (15) ◽  
pp. 183-189 ◽  
Author(s):  
Lorena A. Moreira ◽  
Danté B. Fenolio ◽  
Hélder Lúcio Rodrigues Silva ◽  
Nelson Jorge da Silva Jr
Keyword(s):  
Power Plants ◽  
River Basins ◽  
River Valley ◽  
Hydroelectric Power ◽  
Termite Mounds ◽  
Squamate Reptiles ◽  
Araguaia River ◽  
Hydroelectric Power Plants ◽  
Tocantins River

Termite mounds are known to offer refuge and microhabitats to a great variety of invertebrates and vertebrates. In the valley of the upper Tocantins River, within areas of influence of hydroelectric power plants 4,000 termite mounds were surveyed to evaluate the diversity of amphibians and reptiles using these environments. Surveys in termite mounds from two other areas (Corumbá River and Araguaia River basins) were used for comparative purposes. The results for termitaria in the upper Tocantins river valley revealed nine families, 13 genera, and 25 species of amphibians, and 16 families, 32 genera, and 47 species of squamate reptiles. Compared to a general herpetofaunal list of the region, the data indicate that between 30.6% and 56.8% of the species use termitaria.

scholarly journals Effects of large-scale changes in land cover on the discharge of the Tocantins River, Southeastern Amazonia

2003 ◽  
Vol 283 (1-4) ◽  
pp. 206-217 ◽  
Author(s):  
Marcos Heil Costa ◽  
Aurélie Botta ◽  
Jeffrey A Cardille
Keyword(s):  
Land Cover ◽  
Large Scale ◽  
Tocantins River

scholarly journals Changes in the relationship between society and nature in the Mezzo-region of Southeastern Pará, Amazon, Brazil

2009 ◽  
Vol 39 (4) ◽  
pp. 879-887
Author(s):  
Maurilio de Abreu Monteiro ◽  
Maria Célia Nunes Coelho ◽  
Regiane Paracampos da Silva
Keyword(s):  
Natural Resources ◽  
20Th Century ◽  
River Valley ◽  
Dramatic Decrease ◽  
Satellite Sensors ◽  
Tocantins River ◽  
River Valleys ◽  
The Relationship

With this work, the authors wish to show some of the alterations in the pattern of relations between society and nature, which have taken place throughout the 20th century in the Parauapebas and Itacaiúnas river valleys, as well as in parts of the Tocantins River valley, in southeastern Pará. This is accomplished through descriptions based on Coudreau's first-hand accounts (1889), transcribed in "Voyage a Itaboca et a L'Itacayuna", published in 1897, which depicts an area almost totally covered by forest. This is followed by a counter view made possible through the LandSat 5 satellite sensors, with images of those valleys in 2001, showing the consequences of society transformations and pressure on natural resources, and above all the dramatic decrease in the size of the forest, reduced to 52 percent of the 63,000 square kilometers analyzed herein.

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