14 research outputs found
Effect of salt and osmotic stresses on the germination of pepper seeds of different maturation stages
1,050Â years of Hurricane Strikes on Long Island in The Bahamas
Sedimentary records of past hurricane activity indicate centennial-scale periods over the past millennium with elevated hurricane activity. The search for the underlying mechanism behind these active hurricane periods is confounded by regional variations in their timing. Here, we present a new high resolution paleohurricane record from The Bahamas with a synthesis of published North Atlantic records over the past millennium. We reconstruct hurricane strikes over the past 1,050 years in sediment cores from a blue hole on Long Island in The Bahamas. Coarse-grained deposits in these cores date to the close passage of seven hurricanes over the historical interval. We find that the intensity and angle of approach of these historical storms plays an important role in inducing storm surge near the site. Our new record indicates four active hurricane periods on Long Island that conflict with published records on neighboring islands (Andros and Abaco Island). We demonstrate these three islands do not sample the same storms despite their proximity, and we compile these reconstructions together to create the first regional compilation of annually resolved paleohurricane records in The Bahamas. Integrating our Bahamian compilation with compiled records from the U.S. coastline indicates basin-wide increased storminess during the Medieval Warm Period. Afterward, the hurricane patterns in our Bahamian compilation match those reconstructed along the U.S. East Coast but not in the northeastern Gulf of Mexico. This disconnect may result from shifts in local environmental conditions in the North Atlantic or shifts in hurricane populations from straight-moving to recurving storms over the past millennium
Unassembled polypeptides of the plastidic ribosomes in heat-treated 70S-ribosome-deficient rye leaves
Characterization of the spinach chloroplast genes for the S4 ribosomal protein, tRNAThr (UGU) and tRNASer (GGA)
The localization of genes for ribosomal, cytochrome b6/f complex and photosystems I and II polypeptides on the chloroplast chromosome of Vicia faba
Temas ambientais relevantes Relevant environmental issues
NESTE trabalho, são indicados os principais temas ambientais para o Brasil, num futuro próximo (2022). Impactos do aumento da temperatura são estudados através de cenários, que podem modificar o balanço hÃdrico em algumas regiões, tendo sido observado um aumento da ordem de 0,78ºC no perÃodo de 1917 a 2003, na região de Piracicaba. Para a região amazônica, foi observado um aumento de 0,56ºC durante o século XX. Tanto o desmatamento quanto as Mudanças Climáticas Globais atuam na direção de um aumento da temperatura, enquanto o desmatamento influi na direção de uma diminuição das precipitações. O desmatamento provoca, ainda, uma grande perda de biodiversidade, sendo estimadas em uma perda entre 8.000 até 34.000 espécies, considerando-se que o desmatamento aumenta em 1% ao ano.<br>THIS PAPER indicates the environmental issues that must necessarily be approached, in Brazil, in a near future (2022). A study was made on some aspects of the effects of deforestation and Global Climate Change. A temperature rise around 0,78% has been observed during period of 1917 and 2003 in the Piracicaba region. For the Amazon region a rise of 0,56% was observed the 20th Century. The existing information indicates that not only deforestation but also Global Climate Changes act upon temperature rise. Deforestation has direct influence in precipitation decrease. The consequences of Global Climate Change are still unknown, being that some models indicate a precipitation rise and others a decrease. Deforestation also provokes great biodiversity loss, estimated between 8.000 to 34.000 species, considering that deforestation raises 1% per year