Sediment types and transport modes

2021 ◽  
Vol 437 ◽  
pp. 106497
Author(s):  
Taoliang Zhang ◽  
Rujian Wang ◽  
Wenshen Xiao ◽  
Leonid Polyak ◽  
Anatolii Astakhov ◽  
...  

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
T Batool ◽  
A Neven ◽  
Y Vanrompay ◽  
M Adnan ◽  
P Dendale

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): Special Research Fund (BOF), Hasselt University Introduction The transportation sector is one of the major sectors influencing climate change, contributing around 16% of total Greenhouse gases (GHG) emissions. Aviation contributes to 12% of the transport related emissions. Among other climate change impacts, elevated heat exposure is associated with increased cardiac events and exposure to air pollution caused by GHG emissions has also well-known association with increased cardiovascular related morbidity and mortality. The global temperature rise should be restricted to less than 2 °C which requires keeping carbon emission (CO2) less than 2900 billion tonnes by the end of the 21st century. Assuming air travel a major contributing source to GHG, this study aims to raise the awareness about potential carbon emissions reduction due to air travel of international events like a scientific conference. Purpose Due to the global pandemic of COVID-19, the Preventive cardiology conference 2020 which was planned to be held at Malaga Spain, instead was held in virtual online way. This study aims to calculate the contribution of reduced CO2  emissions in tons due to ESC preventive cardiology conference 2020, which was then held online and air travel of the registered participants was avoided. Methods Anonymized participant registration information was used to determine the country and city of the 949 registered participants of the Preventive Cardiology conference 2020. It is assumed that participants would have travelled from the closest airports from their reported city locations to Malaga airport, Spain. At first, the closest city airports were determined using Google maps and flights information, then the flight emissions (direct and indirect CO2-equivalent emissions) per passenger for the given flight distances were calculated. The CO2 emissions (tons) were calculated for round trips in economy class from the participants of 68 nationalities (excluding 60 participants from Spain as they are assumed to take other modes of transport than airplane). Results In total, 1156.51 tons of CO2  emissions were saved by turning the physical conference into a virtual event. This emission amount is equivalent to the annual CO2 production of 108 people living in high-income countries. Conclusion The pandemic situation has forced us to rethink the necessity of trips by air and has shown us the feasibility of digitally organized events. The information from this study can add to the awareness about reduced amount of carbon emission due to air travel by organizing events in a virtual way when possible. Apart from only digitally organized events there are others options to reduce the carbon footprint of conferences such as limiting the number of physical attendees, encouraging the use of relatively sustainable transport modes for participants from nearby countries (e.g. international trains and use of active transport modes at conference venue etc.) and including CO2 emission offsetting costs.


2021 ◽  
Vol 13 (3) ◽  
pp. 360
Author(s):  
Wensheng Wang ◽  
Martin Gade ◽  
Kerstin Stelzer ◽  
Jörn Kohlus ◽  
Xinyu Zhao ◽  
...  

We developed an extension of a previously proposed classification scheme that is based upon Freeman–Durden and Cloude–Pottier decompositions of polarimetric Synthetic Aperture Radar (SAR) data, along with a Double-Bounce Eigenvalue Relative Difference (DERD) parameter, and a Random Forest (RF) classifier. The extension was done, firstly, by using dual-copolarization SAR data acquired at shorter wavelengths (C- and X-band, in addition to the previously used L-band) and, secondly, by adding indicators derived from the (polarimetric) Kennaugh elements. The performance of the newly developed classification scheme, herein abbreviated as FCDK-RF, was tested using SAR data of exposed intertidal flats. We demonstrate that the FCDK-RF scheme is capable of distinguishing between different sediment types, namely mud and sand, at high spatial accuracies. Moreover, the classification scheme shows good potential in the detection of bivalve beds on the exposed flats. Our results show that the developed FCDK-RF scheme can be applied for the mapping of sediments and habitats in the Wadden Sea on the German North Sea coast using multi-frequency and multi-polarization SAR from ALOS-2 (L-band), Radarsat-2 (C-band) and TerraSAR-X (X-band).


2004 ◽  
Vol 8 (1) ◽  
pp. 95-103 ◽  
Author(s):  
Gil Young Kim ◽  
Michael D. Richardson ◽  
Dale L. Bibee ◽  
Dae Choul Kim ◽  
Roy H. Wilkens ◽  
...  

2009 ◽  
Vol 67 (3) ◽  
pp. 594-605 ◽  
Author(s):  
Victor Quintino ◽  
Rosa Freitas ◽  
Renato Mamede ◽  
Fernando Ricardo ◽  
Ana Maria Rodrigues ◽  
...  

Abstract Quintino, V., Freitas, R., Mamede, R., Ricardo, F., Rodrigues, A. M., Mota, J., Pérez-Ruzafa, Á., and Marcos, C. 2010. Remote sensing of underwater vegetation using single-beam acoustics. – ICES Journal of Marine Science, 67: 594–605. A single-beam, acoustic, ground-discrimination system (QTC VIEW, Series V) was used to study the distribution of underwater macrophytes in a shallow-water coastal system, employing frequencies of 50 and 200 kHz. The study was conducted in Mar Menor, SE Spain, where the expansion of Caulerpa prolifera has contributed to the silting up of the superficial sediments. A direct relationship was identified between algal biomass and sediment-fines content. Acoustic information on sediment grain size and data on algal biomass were obtained in muddy and sandy sediments, including vegetated and non-vegetated seabed. Non-vegetated muddy areas were created by diving and handpicking the algae. The multivariate acoustic data were analysed under the null hypotheses that there were no acoustic differences between bare seabeds with contrasting superficial sediment types or among low, medium, and high algal-biomass areas, having in mind that grain size can act as a confounding factor. Both null hypotheses were rejected, and the results showed that 200 kHz was better than 50 kHz in distinguishing cover levels of algal biomass. The relationship between the 200-kHz acoustic data and algal biomass suggests utility in modelling the latter using the former.


2020 ◽  
Vol 15 (1) ◽  
pp. 721-734
Author(s):  
Do Manh Hao ◽  
Do Trung Sy ◽  
Dao Thi Anh Tuyet ◽  
Le Minh Hiep ◽  
Nguyen Tien Dat ◽  
...  

AbstractLutraria rhynchaena Jonas, 1844 is of great commercial interest, but its reserves have dramatically declined over recent decades. Therefore, there is an urgent need of scientific basis to propose effective fishery management measures and improve artificial aquaculture of the clam. In this study, we investigated the distribution and density of L. rhynchaena, sediment characteristics, and established the clam’s reproductive cycle through monthly observations from August 2017 to July 2018. The study results showed that distribution and density of clams are related to sediment types, and the sediment type of medium sand is likely the best benthic substrate for the clams. The spawning of clams occurred throughout the year with three spawning peaks in January, April and September. For the sustainable management of the clam resource in Cat Ba-Ha Long Bay, the fishery authorities can issue a ban on harvest of the clam in spawning peak months in January, April and September.


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