Geochemistry of large benthic foraminifera Amphisorus hemprichii as a high-resolution proxy for lead pollution in coastal environments

2021 ◽  
Vol 162 ◽  
pp. 111918
Author(s):  
Netramani Sagar ◽  
Aleksey Sadekov ◽  
Peter Scott ◽  
Talia Jenner ◽  
Ashiwin Vadiveloo ◽  
...  
Keyword(s):  
High Resolution ◽  
Benthic Foraminifera ◽  
Lead Pollution ◽  
Coastal Environments ◽  
Large Benthic Foraminifera

scholarly journals Evaluation of UAV LiDAR for Mapping Coastal Environments

2019 ◽  
Vol 11 (24) ◽  
pp. 2893 ◽  
Author(s):  
Yi-Chun Lin ◽  
Yi-Ting Cheng ◽  
Tian Zhou ◽  
Radhika Ravi ◽  
Seyyed Hasheminasab ◽  
...  
Keyword(s):  
High Resolution ◽  
Lake Michigan ◽  
Point Clouds ◽  
Volume Loss ◽  
Coastal Environments ◽  
Average Volume ◽  
Survey Period ◽  
Shoreline Changes ◽  
Point Density ◽  
One Year

Unmanned Aerial Vehicle (UAV)-based remote sensing techniques have demonstrated great potential for monitoring rapid shoreline changes. With image-based approaches utilizing Structure from Motion (SfM), high-resolution Digital Surface Models (DSM), and orthophotos can be generated efficiently using UAV imagery. However, image-based mapping yields relatively poor results in low textured areas as compared to those from LiDAR. This study demonstrates the applicability of UAV LiDAR for mapping coastal environments. A custom-built UAV-based mobile mapping system is used to simultaneously collect LiDAR and imagery data. The quality of LiDAR, as well as image-based point clouds, are investigated and compared over different geomorphic environments in terms of their point density, relative and absolute accuracy, and area coverage. The results suggest that both UAV LiDAR and image-based techniques provide high-resolution and high-quality topographic data, and the point clouds generated by both techniques are compatible within a 5 to 10 cm range. UAV LiDAR has a clear advantage in terms of large and uniform ground coverage over different geomorphic environments, higher point density, and ability to penetrate through vegetation to capture points below the canopy. Furthermore, UAV LiDAR-based data acquisitions are assessed for their applicability in monitoring shoreline changes over two actively eroding sandy beaches along southern Lake Michigan, Dune Acres, and Beverly Shores, through repeated field surveys. The results indicate a considerable volume loss and ridge point retreat over an extended period of one year (May 2018 to May 2019) as well as a short storm-induced period of one month (November 2018 to December 2018). The foredune ridge recession ranges from 0 m to 9 m. The average volume loss at Dune Acres is 18.2 cubic meters per meter and 12.2 cubic meters per meter within the one-year period and storm-induced period, respectively, highlighting the importance of episodic events in coastline changes. The average volume loss at Beverly Shores is 2.8 cubic meters per meter and 2.6 cubic meters per meter within the survey period and storm-induced period, respectively.

scholarly journals Response of large benthic foraminifera to climate and local changes: Implications for future carbonate production

Sedimentology ◽  
2021 ◽  
Author(s):  
Gita R. Narayan ◽  
Claire E. Reymond ◽  
Marleen Stuhr ◽  
Steve Doo ◽  
Christiane Schmidt ◽  
...  
Keyword(s):  
Benthic Foraminifera ◽  
Carbonate Production ◽  
Large Benthic Foraminifera

scholarly journals Ocean acidification induces biochemical and morphological changes in the calcification process of large benthic foraminifera

2015 ◽  
Vol 282 (1803) ◽  
pp. 20142782 ◽  
Author(s):  
Martina Prazeres ◽  
Sven Uthicke ◽  
John M. Pandolfi
Keyword(s):  
Ocean Acidification ◽  
Benthic Foraminifera ◽  
Morphological Changes ◽  
Ambient Conditions ◽  
Skeletal Density ◽  
Buoyant Weight ◽  
Large Benthic Foraminifera ◽  
Sediment Formation ◽  
Ph Conditions ◽  
Main Factor

Large benthic foraminifera are significant contributors to sediment formation on coral reefs, yet they are vulnerable to ocean acidification. Here, we assessed the biochemical and morphological impacts of acidification on the calcification of Amphistegina lessonii and Marginopora vertebralis exposed to different pH conditions. We measured growth rates (surface area and buoyant weight) and Ca-ATPase and Mg-ATPase activities and calculated shell density using micro-computer tomography images. In A. lessonii , we detected a significant decrease in buoyant weight, a reduction in the density of inner skeletal chambers, and an increase of Ca-ATPase and Mg-ATPase activities at pH 7.6 when compared with ambient conditions of pH 8.1. By contrast, M. vertebralis showed an inhibition in Mg-ATPase activity under lowered pH, with growth rate and skeletal density remaining constant. While M. vertebralis is considered to be more sensitive than A. lessonii owing to its high-Mg-calcite skeleton, it appears to be less affected by changes in pH, based on the parameters assessed in this study. We suggest difference in biochemical pathways of calcification as the main factor influencing response to changes in pH levels, and that A. lessonii and M. vertebralis have the ability to regulate biochemical functions to cope with short-term increases in acidity.

scholarly journals Bioerosion by microbial euendoliths in benthic foraminifera from heavy metal-polluted coastal environments of Portovesme (south-western Sardinia, Italy)

2012 ◽  
Vol 9 (11) ◽  
pp. 4607-4620 ◽  
Author(s):  
A. Cherchi ◽  
C. Buosi ◽  
P. Zuddas ◽  
G. De Giudici
Keyword(s):  
Heavy Metal ◽  
Benthic Foraminifera ◽  
Sea Water ◽  
Industrial Area ◽  
Pollution Source ◽  
Coastal Environments ◽  
Molar Ratios ◽  
Structural Types ◽  
Monitoring Survey ◽  
Mg Content

Abstract. A monitoring survey of the coastal area facing the industrial area of Portoscuso-Portovesme (south-western Sardinia, Italy) revealed intense bioerosional processes. Benthic foraminifera collected at the same depth (about 2 m) but at different distances from the pollution source show extensive microbial infestation, anomalous Mg/Ca molar ratios and high levels of heavy metals in the shell associated with a decrease in foraminifera richness, population density and biodiversity with the presence of morphologically abnormal specimens. We found that carbonate dissolution induced by euendoliths is selective, depending on the Mg content and morpho-structural types of foraminiferal taxa. This study provides evidences for a connection between heavy metal dispersion, decrease in pH of the sea-water and bioerosional processes on foraminifera.

scholarly journals HIGH-RESOLUTION ACOUSTIC MAPPING OF GAS CHARGED SEDIMENTS AND LIVING BENTHIC FORAMINIFERA ASSEMBLAGES FROM THE NE REGION OF THE GUANABARA BAY (RJ, BRAZIL)

2016 ◽  
Vol 1 (3) ◽  
Author(s):  
Francielli Paula Delavy ◽  
Alberto Garcia de Figueiredo Jr ◽  
Maria Virgínia Alves Martins ◽  
René Rodrigues ◽  
Egberto Pereira ◽  
...  
Keyword(s):  
High Resolution ◽  
Benthic Foraminifera ◽  
Guanabara Bay ◽  
Acoustic Mapping

Benthic Foraminifera as bio-indicators of anthropogenic impacts in coastal environments: Acqua dei Corsari area case study (Palermo, Italy)

2017 ◽  
Vol 117 (1-2) ◽  
pp. 75-87 ◽  
Author(s):  
Marianna Musco ◽  
Angela Cuttitta ◽  
Erica Bicchi ◽  
Enza Maria Quinci ◽  
Mario Sprovieri ◽  
...  
Keyword(s):  
Benthic Foraminifera ◽  
Anthropogenic Impacts ◽  
Coastal Environments

scholarly journals Decrease in volume and density of foraminiferal shells with progressing ocean acidification

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Azumi Kuroyanagi ◽  
Takahiro Irie ◽  
Shunichi Kinoshita ◽  
Hodaka Kawahata ◽  
Atsushi Suzuki ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Ocean Acidification ◽  
Benthic Foraminifera ◽  
Growth Parameters ◽  
Carbonate Production ◽  
Large Benthic Foraminifera ◽  
Seawater Ph ◽  
Ph Conditions ◽  
Calcification Process ◽  
The Tropics

AbstractRapid increases in anthropogenic atmospheric CO2 partial pressure have led to a decrease in the pH of seawater. Calcifying organisms generally respond negatively to ocean acidification. Foraminifera are one of the major carbonate producers in the ocean; however, whether calcification reduction by ocean acidification affects either foraminiferal shell volume or density, or both, has yet to be investigated. In this study, we cultured asexually reproducing specimens of Amphisorus kudakajimensis, a dinoflagellate endosymbiont-bearing large benthic foraminifera (LBF), under different pH conditions (pH 7.7–8.3, NBS scale). The results suggest that changes in seawater pH would affect not only the quantity (i.e., shell volume) but also the quality (i.e., shell density) of foraminiferal calcification. We proposed that pH and temperature affect these growth parameters differently because (1) they have differences in the contribution to the calcification process (e.g., Ca2+-ATPase and Ω) and (2) pH mainly affects calcification and temperature mainly affects photosynthesis. Our findings also suggest that, under the IPCC RCP8.5 scenario, both ocean acidification and warming will have a significant impact on reef foraminiferal carbonate production by the end of this century, even in the tropics.

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