The Productivity of the C_4 Grass Echinochloa Polystachya on the Amazon Floodplain

Ecology ◽  
1991 ◽  
Vol 72 (4) ◽  
pp. 1456-1463 ◽  
Author(s):  
M. T. F. Piedade ◽  
W. J. Junk ◽  
S. P. Long
Keyword(s):  
Amazon Floodplain ◽  
Echinochloa Polystachya

Very high productivity of the C4 aquatic grass Echinochloa polystachya in the Amazon floodplain confirmed by net ecosystem CO2 flux measurements

Oecologia ◽  
2000 ◽  
Vol 125 (3) ◽  
pp. 400-411 ◽  
Author(s):  
J.I.L. Morison ◽  
M.T.F. Piedade ◽  
E. Müller ◽  
S.P. Long ◽  
W.J. Junk ◽  
...  
Keyword(s):  
Co2 Flux ◽  
High Productivity ◽  
Amazon Floodplain ◽  
Flux Measurements ◽  
Echinochloa Polystachya ◽  
Very High

Vertical mixing in Amazon floodplain lakes

1984 ◽  
Vol 22 (2) ◽  
pp. 1283-1287 ◽  
Author(s):  
Sally MacIntyre ◽  
John M. Melack
Keyword(s):  
Vertical Mixing ◽  
Floodplain Lakes ◽  
Amazon Floodplain

Two New Rhabdocoels (Platyhelminthes) from the Peruvian Amazon Floodplain

2006 ◽  
Vol 15 (5) ◽  
pp. 1609-1620 ◽  
Author(s):  
Noreña Carolina ◽  
Damborenea Cristina ◽  
Escobedo Torres Mario
Keyword(s):  
Peruvian Amazon ◽  
Amazon Floodplain

scholarly journals Fractions of carbohydrates and of nitrogenous compounds of tropical grasses at different cutting ages

2010 ◽  
Vol 39 (7) ◽  
pp. 1538-1547
Author(s):  
Patrícia Regina de Souza Siqueira Campos ◽  
José Fernando Coelho da Silva ◽  
Hernán Maldonado Vásquez ◽  
Andréa Vittori ◽  
Martinho de Almeida e Silva
Keyword(s):  
Small Intestine ◽  
Block Design ◽  
The Other ◽  
Total Carbohydrate ◽  
Nitrogenous Compounds ◽  
Potential Source ◽  
Randomized Block Design ◽  
Ruminal Degradation ◽  
Echinochloa Polystachya ◽  
Carbohydrate Levels

It was evaluated by the Cornell System carbohidrates fractions and nitrogenous compounds of the following grasses at the cutting ages of 14, 28, 42, and 56 days: nilo grass (Acroceras macrum), angola grass (Brachiaria purpurascens), aleman grass (Echinochloa polystachya), limpo grass (Hemarthria altíssima), setaria grass (Setaria anceps), tanner grass (Brachiaria arrecta), and tifton-85 grass (Cynodon spp). The experiment was carried out in a complete randomized block design, in a split plot arrangement in a way that the grasses were evaluated in the plots and the ages of cut in the split-plots. The age of cutting had an effect on the composition of the studied grasses. In most of the grasses, total carbohydrate levels, non-fibrous carbohydrates and A+B1 fraction carbohydrates increased linearly according to the age of cutting. The potentially degradable fraction of carbohydrates (fraction B2) showed a quadratic behavior according to the cutting ages for all grasses. The C fraction of the carbohydrates in tifton-85 grass linearly increased with the age but it did not increase significantly for the other grasses. In setaria grass, the intermediate levels of B2 and B3 nitrogenous fractions were high, which might represent a potential source of protein for ruminal degradation and for the small intestine. Except for setaria grass, all studied grasses show similar values of the A, B1, B2 and B3 nitrogenous fractions.

scholarly journals 240+239Pu depositional signatures as a viable geochronological tool in the Amazon Basin

2017 ◽  
Vol 44 (1) ◽  
pp. 142-149 ◽  
Author(s):  
Luciana M Sanders ◽  
Kathryn H Taffs ◽  
Debra Stokes ◽  
Alex Enrich-Prast ◽  
Christian J Sanders
Keyword(s):  
Amazon Basin ◽  
Environmental Science ◽  
Sediment Cores ◽  
Sediment Accumulation ◽  
Recent Sediment ◽  
Floodplain Lake ◽  
Accumulation Rates ◽  
Amazon Floodplain ◽  
Dating Methods ◽  
Lead 210

AbstractAnthropogenic radionuclide signatures associated with nuclear testing are increasingly utilized in environmental science to explore recent sedimentation. In this study, we assess the suitability of Pu radioisotope analysis in floodplain lake environments in the Amazon Basin to form geochronologies during the 20thcentury. The240Pu +239Pu (240+239Pu) signatures in six sediment cores indicate sediment accumulation rates in the floodplain lakes of the major rivers; Amazon (2.3 mm year-1), Tapajos (10.2 and 2.4 mm year-1) and Madeira (3.4, 4.2 and 6.2 mm year-1). The results from this study show that240+239Pu fallout activities, and the well documented (240Pu/239Pu) atomic ratios of the above ground nuclear tests which began in the 1950’s, are sufficient and well preserved in Amazon floodplain lake sediments to infer chronologies. Lead-210 dating analyses in the same sediment cores produced comparable sediment accumulation rates at three of the six sites. The differences between dating methods may be attributed to the different time scale these dating methods represent and/or in the solubility between Pb and Pu along the sediment column. The geochronologies derived from the240+239Pu and210Pb dating methods outlined in this work are of interest to identify the effects of changing sediment accumulation rates during the previous century as a result of development, including deforestation, along the Amazon Basin which increased towards the middle of the 20thcentury. This study shows that Pu dating provides a viable alternative geochronology tool for recent sediment accumulation (previous ~60 years) along the Amazon Basin.

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