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The trace metal geochemistry of atmospheric dust and terrestrial surface particles were studied on the Qatar Peninsula from February 2014 to November 2015. We included samples of the mega dust-storm event on 01–02 April 2015. Atmospheric dust samples were collected using passive dust traps. Terrestrial surface deposits of recent dust accumulation and traffic particulate from roads were also sampled. All samples were total acid digested and analyzed for major and trace elements using ICP-OES analyzer. The concentration of thirteen elements (Ca, Mg, Ag, As, Cd, Cr, Cu, Mo, Ni, Se, Sn, Sr, Zn) were enriched in atmospheric dust samples, relative to upper continental crust (UCC). Calcium was especially enriched by up to 435% relative to UCC. About 33% of the total sample mass was CaCO3, reflecting the composition of surface rocks and soils in the source areas. Of the elements typically associated with anthropogenic activity, Ag, Ni, and Zn were most enriched relative to UCC, with enrichment factors (EF) of 182%, 233%, and 209%, respectively. Other metals, which normally reflect anthropogenic sources, including Pb and V, were not significantly enriched, with enrichment factors of 25% and 3%, respectively. Major elements (Al, Mn, Fe) were depleted (− 58%, − 35%, and − 5%, respectively) relative to UCC due to the large dilution effect of the enrichment of CaCO3. Back trajectories were determined at the date of sampling for each sample using the NOAA HYSPLIT model. These showed that the source of the dust particles was almost equally divided between northerly and southerly sources, except one sample, which appeared to originate from the west. More variability in particle source locations were observed during the winter months (October to March). Samples from the mega-dust storm were solubilized using an acetic acid-hydroxylamine hydrochloride leach procedure to obtain an upper estimate of the potential contribution of bioactive elements to surface seawater. The leach procedure solubilized a significant fraction of almost all elements. Ca was the element most affected (81% removed) because of the carbonate minerals present. Bioactive elements like Fe (25%) and P (58%) were also significantly solubilized. Because river input is so small to the Arabian Gulf, this solubilized fraction of dust is likely a major source of nutrients to surface seawater. Enrichment factors were also calculated with respect to the average composition of terrestrial surface deposits (TSD). Samples are not enriched significantly with respect to major components (EF < 2), with a depletion in Ca, K, Na in dust storm samples, reflecting a different origin. A significant enrichment of the same trace metals is evident in dust deposits and in traffic samples, but not in dust storms: Cu, Mo, Ni, Zn, possibly deriving from local atmospheric sources (traffic, industries). Samples with northern and southern origins were compared to see if the composition could be used to identify source. Only three elements were observed to be statistically different. Pb and Na were higher in samples from the south, while Cr was higher in those from the north.
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Zooplankton abundance from Ring net samples during the MOSAiC expedition (PS122) in the Central Arctic Ocean
Abundance (ind. m-3) of zooplankton taxa was calculated from samples of Polarstern cruise PS122 (MOSAiC). Samples were taken with a Ring net with an opening area of 0.79 m2 and a mesh size of 1000 µm. Samples were analysed via image-based ZooScan analysis. The classified images are available at the web application EcoTaxa: https://ecotaxa.obs-vlfr.fr/prj/9966.
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- PAR ID:
- 10563079
- Publisher / Repository:
- PANGAEA
- Date Published:
- Subject(s) / Keyword(s):
- Arctic Ocean MOSAiC_ECO net tows Zooplankton Event label Latitude of event Longitude of event Date/Time of event Elevation of event Sample code/label DEPTH, water Depth, water, top/minimum Depth, water, bottom/maximum Volume Comment Solmundaeginidae Aetideidae, copepodites Aetideidae, female Aetideidae, male Aetideopsis spp., female Aglantha digitale Amphipoda Apherusa glacialis Atolla sp. Augaptilidae Augaptilus glacialis, copepodites Augaptilus glacialis, female Augaptilus glacialis, male Botrynema spp. Calanoida indeterminata, copepodites Calanoida indeterminata, female Calanoida indeterminata, male Calanus finmarchicus, c4 Calanus finmarchicus, c5 Calanus finmarchicus, female Calanus glacialis, c4 Calanus glacialis, c5 Calanus glacialis, female Calanus hyperboreus, c3 Calanus hyperboreus, c4 Calanus hyperboreus, c5 Calanus hyperboreus, female Calanus hyperboreus, male Calanus spp. Calanus spp., c3 Calanus spp., c4 Calanus spp., c5 Calanus spp., female Calanus spp., male Chaetognatha Chiridius obtusifrons, female Clione limacina Cnidaria indeterminata Copepoda indeterminata Crustacea, nauplii Corymorpha sp. Ctenophora Cumacea Cyclocaris sp. Decapoda Eukrohnia hamata Euphausiacea Eusirus sp. Fritillariidae Gaetanus brevispinus, female Gaetanus tenuispinus, female Haloptilus sp. Haloptilus sp., female Heterorhabdidae, copepodites Heterorhabdus norvegicus, female Heterorhabdus norvegicus, male Hymenodora glacialis Isopoda Lanceola clausii Limacina spp. Metridia longa Metridia longa, c5 Metridia longa, female Metridia longa, male Oikopleuridae Oncaeidae Ostracoda Paraeuchaeta spp., copepodites Paraeuchaeta spp., c4 Paraeuchaeta spp., c5 Paraeuchaeta spp., female Paraeuchaeta spp., male Paraheterorhabdus sp., copepodites Paraheterorhabdus sp., female Parasagitta elegans Pelagobia sp. Pseudhaloptilus sp. Pseudochirella spectabilis, female Pseudosagitta maxima Scaphocalanus magnus, copepodites Scaphocalanus magnus, female Scaphocalanus spp., copepodites Scaphocalanus spp., female Scaphocalanus spp., male Scina sp. Siphonophorae Sminthea sp. Solmundella sp. Spinocalanus spp., copepodites Spinocalanus antarcticus, copepodites Spinocalanus antarcticus, female Spinocalanus spp., female Spinocalanus spp., male Temorites spp. Themisto spp. Themisto abyssorum Themisto libellula Thysanoessa longicaudata Tomopteris spp. Typhloscolecidae Zooplankton, indeterminata Ring net ZOOSCAN PS122/1 PS122/2 PS122/3 PS122/4 PS122/5 Polarstern Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC)
- Format(s):
- Medium: X Size: 1908 data points Other: text/tab-separated-values
- Size(s):
- 1908 data points
- Location:
- (East Bound Longitude:122.285714; North Bound Latitude:89.026337; South Bound Latitude:79.365119; West Bound Longitude:-2.691093); Arctic Ocean
- Right(s):
- Creative Commons Attribution 4.0 International
- Sponsoring Org:
- National Science Foundation
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