Long-term eutrophication and contamination of the central area of Sepetiba Bay (SW Brazil)

2021 ◽  
Vol 193 (2) ◽  
Author(s):  
Wellen Fernanda Louzada Castelo ◽  
Maria Virgínia Alves Martins ◽  
Paulo Alves de Lima Ferreira ◽  
Rubens Figueira ◽  
Carolina Ferreira da Costa ◽  
...  
Keyword(s):  
Central Area ◽  
Sepetiba Bay

scholarly journals RELATIVE SEA LEVEL RISE EFFECTS AT THE MARAMBAIA BARRIER ISLAND AND GUARATIBA MANGROVE: SEPETIBA BAY (SE BRAZIL)

2019 ◽  
Vol 4 (3) ◽  
pp. 249-262
Author(s):  
Carolina Santana da Costa Santos ◽  
Fábio Ferreira Dias ◽  
Barbara Franz ◽  
Paulo Roberto Alves dos Santos ◽  
Thalita Da Fonseca Rodrigues ◽  
...  
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Rio De Janeiro ◽  
Central Area ◽  
Barrier Island ◽  
Aerial Images ◽  
Relative Sea Level ◽  
Sepetiba Bay ◽  
Se Brazil ◽  
Relative Sea Level Rise

Human activities change coastal ecosystems, but they are also altered by natural causes, such as the relative sea level rise. This work analyzes the influence of changes of the relative sea level at Guaratiba mangrove and Marambaia barrier island, in Sepetiba Bay, Rio de Janeiro State (SE, Brazil), based on photo interpretation. The objective of this study is to analyze the morphodynamics of Marambaia coastal sand barrier, estimating the rate of the shoreline change by mapping the vegetation line position, variations of dune extension and overwash processes. The Marambaia barrier island and Guaratiba mangrove are highly vulnerable to sea level rise. The mangrove is suffering pressure from the relative sea level rising and urbanization. The mangrove migration towards the continent is evident through the analyses of aerial images from 1976 to 2005. If the current erosion process continues in the Marambaia barrier island, a disruption in the central area of the sand bank should occur, which will create a new communication between Sepetiba Bay and the ocean. This break will change the present internal circulation of the bay and modify the ecosystems. Also considering the anthropic pressure, if the Marambaia barrier island breaks, the mangrove area will be reduced or disappear. The sea level rise and the sedimentation rate lowering will result in the migration and marine transgression in Marambaia barrier island and Guaratiba mangrove. EFEITOS DO AUMENTO RELATIVO DO NÍVEL DO MAR NA ILHA BARREIRA DE MARAMBAIA E DO MANGUEZAL DE GUARATIBA: BAÍA DE SEPETIBA (SE BRASIL) ResumoAs atividades humanas alteram os ecossistemas costeiros, mas estes também são alterados por causas naturais, como por exemplo, o aumento relativo do nível do mar. Este trabalho analisa a influência das mudanças relativas do nível do mar no manguezal de Guaratiba e na ilha barreira de Marambaia, na Baía de Sepetiba, localizada no Estado do Rio de Janeiro (SE, Brasil), com base na fotointerpretação. O objetivo deste estudo é analisar a morfodinâmica da barreira costeira de areia de Marambaia, estimando a taxa de variação da linha de costa, mapeando a posição da linha de vegetação, variações da extensão dunar e os processos de overwash. A ilha barreira de Marambaia e o manguezal de Guaratiba são altamente vulneráveis à elevação do nível do mar. O manguezal está sofrendo pressão do aumento relativo do nível do mar e da urbanização. A migração do manguezal para o continente é evidente através da análise de imagens aéreas de 1976 a 2005. Se continuar o processo atual de erosão na ilha barreira de Marambaia, deverá ocorrer uma ruptura na área central do banco de areia, o que dará origem a uma nova comunicação entre a Baía de Sepetiba e a oceano. Essa quebra vai mudar a atual circulação interna da baía e modificar os ecossistemas. Se a ilha barreira de Marambaia se romper, a área de manguezal irá ser reduzida ou desaparecerá. Este efeito é tanto mais provável se for considerada também a pressão antrópica. A elevação do nível do mar e a redução da taxa de sedimentação resultarão na migração e transgressão marinha na barreira de Marambaia e no mangue de Guaratiba. Palavras-chave: Ilha da Barreira. Manguezal. Elevação do nível relativo do mar. Erosão costeira. Galgamento oceânico.

scholarly journals Seagrass Recovery Following Marine Heat Wave Influences Sediment Carbon Stocks

2021 ◽  
Vol 7 ◽  
Author(s):  
Lillian R. Aoki ◽  
Karen J. McGlathery ◽  
Patricia L. Wiberg ◽  
Matthew P. J. Oreska ◽  
Amelie C. Berger ◽  
...  
Keyword(s):  
Heat Wave ◽  
Heat Waves ◽  
Central Area ◽  
Shoot Density ◽  
Seagrass Meadows ◽  
C Stocks ◽  
Sediment Carbon ◽  
The Impact ◽  
Marine Heat Wave

Worldwide, seagrass meadows accumulate significant stocks of organic carbon (C), known as “blue” carbon, which can remain buried for decades to centuries. However, when seagrass meadows are disturbed, these C stocks may be remineralized, leading to significant CO2 emissions. Increasing ocean temperatures, and increasing frequency and severity of heat waves, threaten seagrass meadows and their sediment blue C. To date, no study has directly measured the impact of seagrass declines from high temperatures on sediment C stocks. Here, we use a long-term record of sediment C stocks from a 7-km2, restored eelgrass (Zostera marina) meadow to show that seagrass dieback following a single marine heat wave (MHW) led to significant losses of sediment C. Patterns of sediment C loss and re-accumulation lagged patterns of seagrass recovery. Sediment C losses were concentrated within the central area of the meadow, where sites experienced extreme shoot density declines of 90% during the MHW and net losses of 20% of sediment C over the following 3 years. However, this effect was not uniform; outer meadow sites showed little evidence of shoot declines during the MHW and had net increases of 60% of sediment C over the following 3 years. Overall, sites with higher seagrass recovery maintained 1.7x as much C compared to sites with lower recovery. Our study demonstrates that while seagrass blue C is vulnerable to MHWs, localization of seagrass loss can prevent meadow-wide C losses. Long-term (decadal and beyond) stability of seagrass blue C depends on seagrass resilience to short-term disturbance events.

Taxonomy, valve ultrastructure, nomenclature and a comparison of two species of Bacillariales from freshwaters of Puerto Rico

Phytotaxa ◽  
2020 ◽  
Vol 468 (2) ◽  
pp. 190-202
Author(s):  
J.P. KOCIOLEK ◽  
A. DANZ ◽  
J. SWENSON ◽  
K. THIROUIN ◽  
D.M. WILLIAMS ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Central Area ◽  
Ecological Monitoring ◽  
Virgin Islands ◽  
The U.S

We have investigated two canal-raphe bearing taxa from two freshwater long-term ecological monitoring sites in the NEON program from Puerto Rico. The identity of these two taxa have been misunderstood, and they have been mistaken for one another, due to being similar in size, shape and having interrupted striae across the valve face. Denticula occidentalis Østrup was described from the U.S. Virgin Islands, and like its congeners has fibulae that extend across the valve face as thickened ribs. The species also has valvocopulae that are typical for the genus, with arched sections that clasp onto the knob-like fibulae. Denticula occidentalis has a discontinuous raphe system, and external proximal raphe ends are hooked towards the valve center and elongated. Grunowia portoricensis, sp. nov. has fibulae restricted to the raphe side of the valve, though unlike most members of the genus the fibulae are knob-like. The raphe is continuous across the central area. Though described here as new to science, the species has been illustrated previously from Venezuela. Distinctions between Nitzschia, Denticula and Grunowia are discussed.

scholarly journals Two-year observation of posterior corneal elevations after small incision lenticule extraction (SMILE) for myopia higher than −10 dioptres

2019 ◽  
Vol 104 (1) ◽  
pp. 142-148 ◽  
Author(s):  
Xueyi Zhou ◽  
Jianmin Shang ◽  
Bing Qin ◽  
Yu Zhao ◽  
Xingtao Zhou
Keyword(s):  
Central Area ◽  
Control Group ◽  
Small Incision Lenticule Extraction ◽  
Small Incision ◽  
Long Term Follow Up ◽  
Lenticule Extraction ◽  
Measured Change

AimTo investigate the change in posterior corneal elevations (PCEs) of eyes with extremely high myopia 2 years after small incision lenticule extraction (SMILE).MethodsWe evaluated 39 eyes of 39 patients with spherical equivalent higher than −10.00 dioptres (D). Using a Scheimpflug camera (Pentacam), we measured change in PCEs at 1 day, 3 months, 6 months and 2 years after SMILE. Another 34 eyes of 34 patients who underwent femtosecond laser-assisted in situ keratomileusis (FS-LASIK) were examined before, at 1 day and long-term after surgery as the control group. For each eye, elevations at central, thinnest, maximal points and 24 other predetermined points were measured.ResultsNo significant forward displacements of PCEs were observed in both surgeries. The maximal but not significant forward displacement occurred around 3–6 months following SMILE, and all returned to original levels 6 months postoperatively except superior area. The peripheral area tended to displace backward, while the central area tended forwardly. In both procedures, elevations along horizontal meridians, inferior and temporal hemispheres were significantly higher than those along vertical meridians, superior and nasal hemispheres, respectively (p<0.05). Elevation on the 4 mm, 6 mm diameters at 1 day and on the 6 mm diameter and temporal hemisphere at long-term follow-up postoperatively were significantly higher in FS-LASIK than SMILE (p<0.05). Change in elevations on the 6 mm diameter circle correlated with residual bed thickness (p=0.047).ConclusionsSMILE is a safe way to correct for myopia higher than −10 D, with PCEs remaining stable 2 years after surgery.

Republished: Pipeline embolization device thrombosis induced peri-construct collateral channels

2015 ◽  
Vol 8 (11) ◽  
pp. e47-e47 ◽  
Author(s):  
Albert Ho Yuen Chiu ◽  
Thomas R Marotta
Keyword(s):  
Anterior Cerebral Artery ◽  
Central Area ◽  
Artery Aneurysm ◽  
Biologically Active ◽  
Pipeline Embolization Device ◽  
Long Term Follow Up ◽  
Anterior Cerebral Artery Aneurysm ◽  
Cerebral Artery Aneurysm

More than half a decade of experience and follow-up has now been accumulated with regard to flow diversion as a treatment for intracranial aneurysms; however, many uncertainties, such as the nature of aneurysmal remnants and the meaning of non-regressed, non-perfused aneurysmal masses, are still unknown. Here we discuss a 22-year-old man who presented with a grade 1 subarachnoid hemorrhage secondary to a dissecting right anterior cerebral artery aneurysm who was subsequently treated with a Pipeline Embolization Device construct. After ceasing dual antiplatelet therapy himself, he was found on MRI to have an area of increased aneurysmal remnant reperfusion. This was found to connect to multiple channels which reconstituted flow within the distal construct on angiography. The central area of construct thrombosis could not be visualized on MRI. The finding suggests that non-opacified aneurysmal remnants that have not regressed are biologically active and raises concerns regarding using MRI for long term follow-up.

scholarly journals Relationships between columnar aerosol optical properties and surface particulate matter observations in north-central Spain from long-term records (2003–2011)

2014 ◽  
Vol 7 (6) ◽  
pp. 5829-5882 ◽  
Author(s):  
Y. S. Bennouna ◽  
V. Cachorro ◽  
M. A. Burgos ◽  
C. Toledano ◽  
B. Torres ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Annual Cycle ◽  
Central Area ◽  
Central Spain ◽  
North Central ◽  
Desert Dust ◽  
The North ◽  
Daily Data ◽  
Dust Events

Abstract. This work examines the relationships between Aerosol Optical Depth (AOD) and Particulate Matter (PMX) parameters, based on long records (2003–2011) of two nearby sites from the AERONET and EMEP networks in the north-central area of Spain. The climatological annual cycle of PM10 and PM2.5 present a bimodality which might be partly due to desert dust intrusions, a pattern which does not appear in the annual cycle of the AOD. In the case of the AOD, this bimodality is likely to be masked because of the poor sampling of sunphotometer data as compared to PMX (67% of days against 90%), and this fact stresses the necessity of long-term observations. In monthly series, significant interannual variations are observed and most extrema coincide, however the bimodal shape remains relatively stable for PMX. Significant and consistent trends were found for both datasets likely associated to a decrease of desert dust apportionment until 2009. PM10 and AOD daily data are moderately correlated (0.56), a correlation improving for monthly means (0.70). In the case of strong desert dust events day-to-day correlation is not systematic, therefore an extensive analysis on PMX, fine-PM ratio, AOD and associated Ångström exponent (α) is carried out.

scholarly journals Long-term (2001–2012) fine particulate matter (PM<sub>2.5</sub>) and the impact on human health in Beijing, China

2014 ◽  
Vol 14 (21) ◽  
pp. 28657-28684 ◽  
Author(s):  
S. Zheng ◽  
A. Pozzer ◽  
C. X. Cao ◽  
J. Lelieveld
Keyword(s):  
Human Health ◽  
Fine Particulate Matter ◽  
Pollution Abatement ◽  
Central Area ◽  
Total Mortality ◽  
Premature Mortality ◽  
Boundary Layer Height ◽  
Pollutant Concentrations ◽  
The Impact

Abstract. Beijing, the capital of China, is a densely populated city with poor air quality. The impact of high pollutant concentrations, in particular of aerosol particles, on human health is of major concern. The present study uses Aerosol Optical Depth (AOD) as proxy to estimate long-term PM2.5, and subsequently estimates the premature mortality due to PM2.5. We use the AOD from 2001 to 2012 from the Aerosol Robotic Network (AERONET) site in Beijing and the ground-based PM2.5 observations from the US embassy in Beijing from 2010 to 2011, to establish a relationship between PM2.5 and AOD. By including the atmospheric boundary layer height and relative humidity in the comparative analysis, the correlation (R2) increases from 0.28 to 0.62. We evaluate 12 years of PM2.5 data for the Beijing central area using an estimated linear relationship with AOD, and calculate the yearly premature mortality by different diseases attributable to PM2.5. The estimated average total mortality due to PM2.5 is about 6100 individuals yr−1 for the period 2001–2012 in the Beijing central area, and for the period 2010–2012 the per capita mortality for all ages due to PM2.5 is around 17.9 per 10 000 person-year, which underscores the urgent need for air pollution abatement.

scholarly journals Characteristics of Bromus cartharticus Vahl (Poaceae) natural populations collected in the central area of Argentina

2009 ◽  
Vol 66 (2) ◽  
pp. 276-279 ◽  
Author(s):  
Beatriz Rosso ◽  
Elba Pagano ◽  
Pedro Rimieri ◽  
Raúl Ríos
Keyword(s):  
Agronomic Traits ◽  
Natural Populations ◽  
Central Area ◽  
Germplasm Bank ◽  
Marginal Areas

Collection of Bromus catharticus Vahl was carried out in the Argentine humid and sub-humid central area. Sixty-eight natural populations are conserved for medium and long term in Pergamino Germplasm Bank and in IRB Germplasm Bank, and ten morphological and agronomic traits were evaluated in the field during two years. There was variability for the traits considered among the accessions. Those populations from the subhumid area showed differences in valuable attributes for breeding. Exploration of marginal areas for this species might be an effective way to add variability to this collection.

scholarly journals Recent Evolution of the Intertidal Sand Ridge Lines of the Dongsha Shoal in the Modern Radial Sand Ridges, East China

2021 ◽  
Vol 18 (4) ◽  
pp. 1573
Author(s):  
Binglin Liu ◽  
Haotian Wu ◽  
Zhenke Zhang ◽  
Guoen Wei ◽  
Yue Wang ◽  
...  
Keyword(s):  
Morphological Evolution ◽  
Central Area ◽  
Research Area ◽  
Sediment Supply ◽  
Sand Ridge ◽  
Ecological Value ◽  
Ridge Line ◽  
Sand Ridges ◽  
Radial Sand Ridges

The Dongsha Shoal is one of the largest shoals in the South Yellow Sea and has important marine ecological value. The shoal extends in a south–north direction and is controlled by the regional dominating tidal currents. Recently, due to human activities and some natural factors, the geomorphic dynamics of the Dongsha Shoal has undergone drastic changes. However, few people have proposed quantitative research on the changes of tidal flat morphology, let alone the long-term sequence analysis of sand ridge lines. Hence, we attempt to take the Dongsha Shoal in the Radial Sand Ridges as the research area, and analyze the trends of the long-term morphological evolution of the sand ridge lines over the period 1973–2016 based on a high-density time series of medium-resolution satellite images. The sand ridge line generally moves from southeast to northwest, and the position distribution of the sand ridge line from north to south has gradually changed from compact to scattered. We also found that the geomorphological dynamics at different positions of the sand ridge line are inconsistent. The north and south wings are eroded on the west side, while the central area is eroded on the east side. Most of the sand ridge line is moving eastward. In addition, the change of sand ridge line is affected by multiple factors such as sediment supply, typhoon, reclamation and laver cultivation.

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