The shrub-arboreal layer floral diversity of three stricto sensu cerrado area in Tocantins Diversidad florística de estratto arbóreo arbustiva de tres zonas de cerrado stricto sensu, Tocantins
Abstract. Methane (CH4) atmospheric mixing ratio measurements are analyzed for the period between June 2013 and November 2018 at the Amazon Tall Tower Observatory (ATTO). We describe the seasonal and diurnal patterns of nighttime events in which CH4 mixing ratios at the uppermost (79 m a.g.l.) inlet are significantly higher than the lowermost inlet (4 m a.g.l.) by 8 ppb or more. These nighttime events were found to be associated with a wind direction originating from the southeast and wind speeds between 2 and 5 m s−1. We found that these events happen under specific nighttime atmospheric conditions when compared to other nights, exhibiting less variable sensible heat flux, low net radiation and a strong thermal stratification above the canopy. Our analysis indicates that even at wind speeds of 5.8 m s−1 the turbulence intensity, given by the standard deviation of the vertical velocity, is suppressed to values lower than 0.3 m s−1. Given these findings, we suggest that these nighttime CH4 enhancements are advected from their source location by horizontal nonturbulent motions. The most likely source location is the Uatumã River, possibly influenced by dead stands of flooded forest trees that may be enhancing CH4 emissions from those areas. Finally, biomass burning and the Amazon River were discarded as potential CH4 sources.
Abstract.Emissions of gases and particulates in urban areas are associated with a mixture of various sources, both natural and anthropogenic. Understanding and quantifying these emissions is necessary in studies of climate change, local air pollution issues and weather modification. Studies have highlighted that the transport sector is key to closing the world's emissions gap. 15Vehicles contribute substantially with the emission of carbon dioxide (CO 2 ), carbon monoxide (CO), nitrogen oxides (NO x ), nonmethane hydrocarbon (NMHC), particulate matter (PM), methane (CH 4 ), hydrofluorocarbon (HFC) and nitrous oxide (N 2 O).Several studies show that vehicle emission inventories are an important approach to providing a baseline estimate of on-road emissions in several scales, mainly in urban areas. This approach is essential to areas with incomplete or non-existent monitoring networks as well as for air quality models. Conversely, the direct downscale of global emission inventories in chemical transport 20and air quality models may not be able to reproduce the observed evolution of atmospheric pollution processes at finer spatial scales. To address this caveat, we developed a bottom-up vehicular emission inventory along the 258 main traffic routes from Manaus, based on local vehicle fleet data and emission factors (EFs). The results show that the light vehicles are responsible for the largest fraction of the pollutants, contributing 2.6, 0.87, 0.32, 0.03, 456 and 0.8 ton/h of CO, NO x , CH 4 , PM, CO 2 and NMHC, respectively. Including the emissions of motorcycles, buses and trucks, our total estimation of the emissions is 4.1, 1.0 , 25 0.37, 0.07, 63.5 and 2.56 ton/h, respectively. We also noted that light vehicles accounted for about 62.8%, 84.7%, 87.9%, 45.1%, 71.8%, and 33.9% and motorcycles in the order of 32.3 %, 6.5 %, 12.1 %, 6.2 %, 14.8 %, 8.7 %, respectively. Nevertheless, we can highlight the bus emissions which are around 35.7% and 45.3 % for NMHC and PM. Our results indicate a better distribution over the domain reflecting the influences of standard behavior of traffic distribution per vehicle category. Finally, this inventory provides more detailed information to improving the current understanding of how vehicle emissions contribute to the ambient 30 pollutant concentrations in Manaus and their impacts on regional climate changes. This work will also contribute to improved air quality numerical simulations, provide more accurate scenarios for policymakers and regulatory agencies to develop strategies for controlling the vehicular emissions, and, consequently, mitigate associated impacts on local and regional scales of the Amazon ecosystems. 35Key words: Vehicle emission inventories, bottom-up approach, urban air pollution, Amazon forest Geosci. Model Dev. Discuss., https://doi
<p>Objetivou-se verificar a produção de serapilheira de duas fisionomias do domínio Cerrado, sendo uma fisionomia de cerrado <em>sensu stricto</em> (<em>s.s</em>) e outra de mata ciliar, ambas as áreas estão localizadas na Fazenda Experimental da Universidade Federal do Tocantins, <em>Campus</em> de Gurupi-TO. Foram instalados aleatoriamente em cada uma das fisionomias estudadas dez coletores de 1 x 1 m, os quais foram monitorados mensalmente durante o período maio de 2012 a abril de 2013. A produção média de serapilheira total mostrou variação apenas no mês de outubro de 2012 e fevereiro de 2013 com uma produção anual de 1829,31 kg ha<sup>-1</sup> na fisionomia de mata ciliar e de 1349,01 kg ha<sup>-1 </sup>na fisionomia de cerrado <em>s.s. </em>A fração mais representativa da serapilheira total encontrada nas duas fisionomias estudadas foi composta por folhas que perfazem 63,6% do total de material depositado nos coletores seguido pelas frações material lenhoso, flor e propágulo respectivamente.</p><p align="center"><strong><em>Leaflitter production in two Cerrado types, Gurupi, state Tocantins</em></strong></p><p><strong>Abstract</strong><strong>: </strong>The objective was to verify the leaflitter production of the two Cerrado types, one being <em>stricto sensu</em> Cerrado (s.s) and other riparian forests, both areas are located at the Experimental Farm of the Federal University of Tocantins, Campus of Gurupi-TO. Ten collectors of 1 x 1 m were randomly installed in each of the studied areas, which were monitored monthly during the period of May 2012 to April 2013. The mean litter production showed variation only in the month of October 2012 and February 2013 with an annual output of 1829.31 kg ha<sup>-1</sup> in the riparian physiognomy and 1349.01 kg ha<sup>-1</sup> in the s.s. cerrado. The most representative fraction of Total litter found in the two physiognomies studied consisted of leaves making up 63.6% of the total material deposited in the traps followed by the timber fraction, flower and propagules respectively.</p>
Foram analisados 36 dos cultivares de batata (Solanum tuberosum L.) existentes no Instituto Agronômico, quanto ao teor de glicoalcalóides totais (TGA) na porção superficial dos tubérculos, e quanto à sua capacidade de esverdeamento, duas características importantes na comercialização do produto. As determinações foram feitas para tubérculos recém-colhidos, armazenados na ausência e na presença de luz, ambos por 25 dias. Os teores de TGA situaram-se na faixa de 3-24mg/100g de peso fresco. Tanto as condições de armazenamento quanto os cultivares influenciaram o teor de TGA e a capacidade de esverdeamento. Encontrou-se uma correlação linear significativa entre o teor de TGA e a capacidade de esverdeamento, independentemente de tratamentos e cultivares, negativa, porém, para tubérculos recém-colhidos. Os dados obtidos sugerem que ambos os fatores são influenciados por características genéticas peculiares a cada cultivar.
Objetivou-se caracterizar a florística e a fitossociologia de um fragmento de cerrado sensu stricto, localizado em Gurupi, Tocantins. O estudo foi realizado na Reserva legal da fazenda experimental da Universidade Federal do Tocantins, campus de Gurupi, Tocantins. Foram implantadas cinco parcelas de 20x50m, totalizando 5000m² e amostrados todos os indivíduos com circunferência maior ou igual a 10 cm, ao nível do solo (CAS). Foram registrados 906 indivíduos arbustivo-arbóreo pertencentes a 42 famílias, 102 espécies e 78 gêneros. As famílias que se destacarem em numero de indivíduos, frequência, dominância foram Myrtacea, Vochystaceae, Burseraceae e Fabaceae, entre os indivíduos os principais foram Myrcia fallax (Rich) DC, Protium heptaphyllum (Aubl) Marchand e Qualea multiflora Mart. O índice de diversidade de Shannon (H´) foi de 3,70 e equabilidade J´0,80, sendo considerados padrões para a região do cerrado.
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