Copper concentrations in surface waters off the south-eastern atlantic coast, U.S.A.

ABSTRACT: In this paper, we present new evidence regarding a Marine Isotope Stage 3 (MIS3) transgression on the south-eastern Brazilian coast (Baixada Santista coastal plain). Data collected from a Standard Penetration Test (SPT) drilling reveal the occurrence of myxohaline sediments between cal BP 45,000 and 41,000. A deeper sequence, which shows a clear transition from terrestrial to a myxohaline environment, was associated with MIS5e. Organic and inorganic proxies have been used to recognize the variations on the terrestrial/myxohaline/marine deposits, as well as to infer about climate and energy of the depositional environment. Environmental change, which could correspond to a sea-level peak or the occurrence of drier conditions, was recognized between 43,000 and 42,000 cal BP. The results reinforce the need for future works on MIS3 variability on the South American Atlantic coast.

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The Handsome Cross Grasshopper Oedaleus decorus (Germar, 1825) (Orthoptera: Acrididae) as a Neglected Pest in the South-Eastern Part of West Siberian Plain

Insects ◽

10.3390/insects13010049 ◽

2022 ◽

Vol 13 (1) ◽

pp. 49

Author(s):

Kristina V. Popova ◽

Natalya S. Baturina ◽

Vladimir V. Molodtsov ◽

Oxana V. Yefremova ◽

Vasily D. Zharkov ◽

...

Keyword(s):

Atlantic Coast ◽

West Siberian Plain ◽

The South ◽

South Eastern ◽

The Pacific ◽

Important Pest ◽

The 1960S ◽

Almost All ◽

Arid Territories ◽

Semi Arid

Oedaleus decorus is a widely distributed acridid over the Eurasian semi-arid territories, from the Atlantic coast to the Pacific coast. In many semi-arid territories, O. decorus was and is the most important pest, but in the south-eastern part of West Siberian Plain, it was not considered a pest until the 1960s. We compared two sets of data on the acridid distribution in the region: before 1960 and from 1961 until 2021. Until the 1960s, the species occurred mainly in the southern steppes. Since the 1960s, its distribution changed significantly. Nowadays, it occupies almost all local steppes and the southern part of the forest-steppes and can be also found on the eastern side of the Ob River. These shifts may be explained by both climatic changes and changes in human activities. During upsurges the densities of O. decorus were often more than one to two adults per square meter. It is often abundant in the same habitats and in the same periods as the Italian locust (Calliptamus italicus)—one of the most important acridid pests. This means during joint outbreaks these two species can simultaneously damage almost all spectrum of plants.

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Mercury in king mackerel, Scomberomorus cavalla, and Spanish mackerel, S. maculatus, from waters of the south-eastern USA: regional and historical trends

Marine and Freshwater Research ◽

10.1071/mf06096 ◽

2007 ◽

Vol 58 (2) ◽

pp. 187 ◽

Cited By ~ 21

Author(s):

Douglas H. Adams ◽

Robert H. McMichael

Keyword(s):

Gulf Of Mexico ◽

Total Mercury ◽

Gulf Coast ◽

Atlantic Coast ◽

Fish Length ◽

The South ◽

Spanish Mackerel ◽

South Eastern ◽

Eastern Usa ◽

King Mackerel

Mackerels and other piscivorous marine fishes can contain significant levels of mercury. To monitor and better understand mercury levels in mackerel populations, total mercury concentrations were analysed in dorsal muscle tissue from 279 king mackerel, Scomberomorus cavalla, and from 580 Spanish mackerel, S. maculatus, collected from offshore and coastal waters of the Atlantic Ocean and Gulf of Mexico in the south-eastern USA. Mercury levels in king mackerel ranged from 0.19 to 3.6 ppm (mean = 0.94 ppm; median = 0.65 ppm) on the Atlantic coast and from 0.18 to 4.0 ppm (mean = 1.51 ppm; median = 1.3 ppm) on the gulf coast. Total mercury levels for Spanish mackerel ranged from 0.04 to 1.3 ppm (mean = 0.32 ppm; median = 0.27 ppm) on the Atlantic coast and from 0.09 to 3.2 ppm (mean = 0.53 ppm; median = 0.44 ppm) on the gulf coast. Data from the present study suggest that Gulf of Mexico king and Spanish mackerel contain significantly higher levels of mercury than those from the Atlantic coast. Total mercury levels and fish length were positively related in both species and in both regions. A positive relationship between total mercury levels and king mackerel age was also detected. No differences in mercury levels were observed between males and females within either species. Comparisons of pre- and post-1996 mercury levels indicated a short-term historical decline in total mercury levels of Spanish mackerel from gulf-coast waters between 1990 and 2002. Further, mercury levels of these species were higher than those recorded in the 1970s.

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Seasonal cycling of zinc and cobalt in the south-eastern Atlantic along the GEOTRACES GA10 section

Biogeosciences ◽

10.5194/bg-18-4265-2021 ◽

2021 ◽

Vol 18 (14) ◽

pp. 4265-4280

Author(s):

Neil J. Wyatt ◽

Angela Milne ◽

Eric P. Achterberg ◽

Thomas J. Browning ◽

Heather A. Bouman ◽

...

Keyword(s):

Surface Water ◽

Mixed Layer ◽

Surface Waters ◽

Early Spring ◽

External Input ◽

The South ◽

Austral Spring ◽

South Eastern ◽

Eastern Atlantic Ocean ◽

Offshore Transport

Abstract. We report the distributions and stoichiometry of dissolved zinc (dZn) and cobalt (dCo) in sub-tropical and sub-Antarctic waters of the south-eastern Atlantic Ocean during austral spring 2010 and summer 2011/2012. In sub-tropical surface waters, mixed-layer dZn and dCo concentrations during early spring were 1.60 ± 2.58 nM and 30 ± 11 pM, respectively, compared with summer values of 0.14 ± 0.08 nM and 24 ± 6 pM. The elevated spring dZn concentrations resulted from an apparent offshore transport of elevated dZn at depths between 20–55 m, derived from the Agulhas Bank. In contrast, open-ocean sub-Antarctic surface waters displayed largely consistent inter-seasonal mixed-layer dZn and dCo concentrations of 0.10 ± 0.07 nM and 11 ± 5 pM, respectively. Trace metal stoichiometry, calculated from concentration inventories, suggests a greater overall removal for dZn relative to dCo in the upper water column of the south-eastern Atlantic, with inter-seasonally decreasing dZn / dCo inventory ratios of 19–5 and 13–7 mol mol−1 for sub-tropical surface water and sub-Antarctic surface water, respectively. In this paper, we investigate how the seasonal influences of external input and phytoplankton succession may relate to the distribution of dZn and dCo and variation in dZn / dCo stoichiometry across these two distinct ecological regimes in the south-eastern Atlantic.

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