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EcoQS assessment of the marine intertidal zone based on its fauna is challenging because the assemblages have a low diversity and consist of stress tolerant species. The new approach we propose is to pool foraminiferal diversity (effective number of species exp(H' bc )) across the whole intertidal zone including the salt marsh and tidal flat. In seven fjordheads studied in northern Fennoscandia, polycyclic aromatic hydrocarbon (PAH) concentrations indicated low levels of pollution (EcoQS PAH Excellent to Moderate). Jadammina or Balticammina dominated the salt marsh, Elphidium albiumbilicatum, Elphidium williamsoni, Elphidium clavatum, and Buccella frigida occurred in the tidal flat. Ovammina opaca thrived in both belts. While foraminiferal test abnormalities are often proposed to measure pollution impacts, we did not detect any correlation with PAHs. EcoQS based on foraminiferal diversity (EcoQS foram Excellent to Good) matched EcoQS based on PAHs suggesting that pooled foraminiferal diversity reliably measures intertidal EcoQS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The article presents a microphotograph dataset of 106 taxa of benthic foraminifera (BF) from surface sediments collected at 26 grab station during RV Akademik Ioffe 51st cruise (summer 2016). The selected stations are located along a 59.5°N transect in the North Atlantic. This is the key area of climate control, where the interaction of warm surface and cold deep water masses takes place, which affects the operation of the global oceanic thermohaline circulation. The analysis of the benthic foraminiferal assemblages allows us to describe the properties of bottom water mass, to draw conclusions about the environmental parameters at the bottom. This photo dataset will facilitate the identification of species of BF, and thus will accelerate the routine process of micropaleontological analysis and the subsequent reconstruction of environmental conditions., (© 2019 The Authors.)

Current 'Atlantification' of the Arctic Ocean affects benthic communities leading to the changes in their structure and abundance. Such areas as Svalbard that are seasonally affected by Atlantic and Arctic water masses may give a possibility to preliminary estimate the response of benthic communities to short-term environmental changes and to evaluate their sensitivity. We have sampled Kongsfjorden for modern benthic foraminifera in three different seasons. The record includes data on the abundances of benthic foraminiferal species in the surface sediments (0-2cm). This data gives an insight into the seasonal dynamics of the near-glacial foraminiferal community of Kongsfjorden.

Glaciers in the fjords of Svalbard have been receding over last decades. Tempelfjorden, a typical glaciated fjord in West Spitsbergen (78°24'06″ N, 17°02'30″ E), has been sampled in summer 1995 and 2001-2007 for modern benthic foraminifera. We have normalized the abundances and unified the taxonomy of all these published and unpublished data sets and then compiled the record of foraminiferal assemblages changing over years into a comprehensive database. The record includes data on living and dead abundances of benthic foraminiferal species in the surface sediments (0-2 cm) and downcore abundances of living foraminifera (only for 2004). This database portrays benthic foraminifera, this key group of microfossils, in a gradually changing Arctic environment.

Living benthic foraminifera, known as environmental bio-indicators of both natural and anthropogenic conditions in marine environments, were investigated in the coastal environment of Roscoff Aber Bay (Brittany, France). Eight sampling sites subject to natural variations (freshwater inputs, tides) and/or anthropogenic impacts (pollution, eutrophication) were studied over four seasons in 2021–2022 (November, February, May, August). We sought to understand the spatial distribution of foraminiferal populations within and between sampling sites over the different seasons and to identify sensitive species and those tolerant to anthropogenic impacts. To this end, sedimentary and biogeochemical characteristics of the sediments were examined by measuring grain size, temperature, oxygen, salinity, pH, environmental pigment concentration (chl a and phaeopigments), total organic carbon (TOC), isotopic ratios of carbon (δ13C), nitrogen (δ15N) and sulfide (δ34S), and chl a fluorescence. Considering these parameters as potential driving factors, four environments were distinguished among the sampling sites: open water, terrestrial, oligotrophic and eutrophic. These showed an increasing gradient of organic supply as well as very different microbial activities, highlighted by carbon and sulfide isotopic ratios. Foraminiferal population study revealed the dominant species characterising these main environments. The lowest abundance but highest diversity of foraminifera was found in the harbour site, associated with the dominance of Haynesina germanica, suggesting this species is tolerant to eutrophic environments and anthropogenic impacts. Open water was dominated by Ammonia beccarii and Elphidium crispum, while Quinqueloculina seminula was the most abundant species in the site with the greatest terrestrial influence. Interestingly, the observed organic enrichment of the harbour due to anthropogenic activities (fisheries, waste deposits, etc.) does not seem to significantly affect foraminiferal diversity. Overall, the benthic foraminiferal species in Roscoff Aber Bay appear to be an excellent proxy for marine environmental conditions under various natural and anthropogenic influences. [ABSTRACT FROM AUTHOR]

Benthic foraminifera are unicellular marine micro-organism with a hard exoskeleton and commonly present in the benthic community of marine ecosystem. This study aimed to identify the benthic foraminifera present along the coastal areas of eight municipalities in Biliran Island, Philippines. Quadrat sampling was conducted and three samples per quadrant transect of 1 m x 1 m divided into nine squares were collected. The samples were then observed under the microscope, and the specimens seen were identified by comparing them with the images of the sample species from the website https://marinespecies.org/. The researchers conducted an in-situ collection of the foraminiferal shells from intertidal areas along shallow water coastlines of the island. Results showed that the coastal environment of Biliran Island has the presence of the genera Spirillina, Quinqueloculina, Marginopora and Sorites. The identified species were classified based on their feeding mechanisms as herbivory and passive suspension feeding. The presence of benthic foraminifera species along the coastal environments of Biliran Island provides a record of the environment where they are found, making them natural bioindicators of water quality. This study provides a baseline for further studies on the distribution and abundance of benthic foraminifera in the area and can contribute to the understanding of the environmental conditions of the coastal areas in Biliran Island. [ABSTRACT FROM AUTHOR]

The response and the safety of geostructures constructed on hilly regions or sloping grounds are receiving increased attention. As the foundation of geostructures resting on slopes is often in the vadose zone, accounting for appropriate properties of partially saturated soil is essential for effective design. Moreover, changes in climatic conditions will adversely affect the load-carrying capacity and the stability of the footing resting on unsaturated slopes. Often, the soil–water retention curve (SWRC) at null stress is adopted but is expected to be affected by various factors, including the stress state of the sample. In the present study, an attempt has been made to demonstrate the effectiveness of using stress-dependent SWRC (SDSWRC) in analyzing a footing resting on a slope exposed to seasonal variations. The SDSWRC along the drying–wetting path determined experimentally was fitted using the standard SWRC model. The key parameters of the SDSWRC, hydraulic conductivity function, and shear strength of unsaturated soils are utilized in numerical modeling. Transient state flux analysis is carried out to mark the effects of SDSWRC in the development of hydraulic response. The stability of an unsaturated slope subjected to a footing load located at a chosen setback distance was assessed under various hydromechanical conditions. The results demonstrate that the seasonal variation, water table position, and net stress significantly influence the stability and the load-carrying capacity of the footing resting on an unsaturated slope. [ABSTRACT FROM AUTHOR]

This study describes the prevalent sedimentological and geochemical patterns and investigates the environmental status of the bottom of Gialova lagoon, a highly vulnerable coastal site of the EU's Natura 2000 network. For this task, lithological, geochemical, and microfaunal analyses of sediment samples were combined with a high-resolution bathymetric survey. Potential pollution was determined using geochemical-based (EF, I-geo, and PLI) and faunal (Foram-AMBI) indices. We find that sedimentation is mainly controlled by the bottom morphology, hydrodynamic variations, and biogenic productivity of the lagoon. The application of the multivariate factor analysis technique revealed four dominant factors explaining the geochemical processes occurring in the lagoon. The first factor, namely "terrigenous aluminosilicates associated with Corg vs. autochthonous biogenic carbonates", discriminates the deposition of detrital sediments, related to the high adsorption of heavy metals—versus bioclastic sediments. The "sulfides" factor represents an anoxic phase of the lagoon floor, whereas the "Mn-oxyhydroxides" factor indicates increased manganese content with several compounded trace elements. The "phosphate" factor reveals multiple sources of phosphorus in the lagoon. The lagoon bottom shows negligible to minor contamination in heavy metals, except Mo and Pb, which induce moderate pollution levels. The maximum contamination and environmental stress concern two small-sized, shallow basins within the lagoon. [ABSTRACT FROM AUTHOR]

Svalbard spans large climate gradients, associated with atmospheric circulation patterns and variations in ocean heat content and sea ice cover. Future precipitation increases are projected to peak in the northeast and to mainly occur in winter, but uncertainties underscore the need for reconstructions of long‐term spatial and temporal variations in precipitation amounts and seasonality. We use lipid biomarkers from four sedimentary lake records along a climatic gradient from western to northeastern Svalbard to reconstruct Holocene water cycle changes. We measured the leaf wax hydrogen isotopic composition of long‐chain (terrestrial) and mid‐chain (aquatic) n‐alkanoic acids, reflecting δ2H of precipitation (δ2Hprecip) and lake water (δ2Hlake), respectively. δ2Hprecip values mainly reflect summer precipitation δ2H and evapotranspiration, whereas δ2Hlake values can reflect various precipitation seasonality due to varying lake hydrology. For one lake, we used the difference between δ2Hprecip and δ2Hlake (εprecip‐lake) to infer summer evapotranspiration changes. Relatively 2H‐enriched δ2Hprecip values and higher εprecip‐lake in the Early and Middle Holocene suggest warm summers with higher evapotranspiration, and/or more proximal summer moisture. After c. 6 cal. ka BP, 2H‐depleted δ2Hprecip values and lower εprecip‐lake indicate summer cooling, less evapotranspiration, or more distally derived moisture. Early to Middle Holocene decrease in δ2Hlake values in two northern Spitsbergen lakes reflects an increase in the proportion of winter relative to summer precipitation, associated with regional warming and increased moisture supply, which may be due to increased distal moisture supply and/or reduced sea ice cover. Our northern Svalbard δ2Hlake records suggest great Late Holocene climate variability with periodic winter precipitation increases or decreases in summer precipitation inflow to the lakes. We find that Holocene summer precipitation δ2H values mainly follow changes in summer insolation and temperature, whereas the seasonal distribution of precipitation is sensitive to catchment hydrology, regional ocean surface conditions, and moisture source changes. [ABSTRACT FROM AUTHOR]