One of the challenges in monitoring the marine coastal environments is quantifying the magnitude ... more One of the challenges in monitoring the marine coastal environments is quantifying the magnitude and duration of pollution events. This study introduces a new concept of defining heavy metal (HM) baseline assessment levels (BALs) in coastal environments using foraminiferal shells. We demonstrated the potential of this approach by examining a nature reserve along the Mediterranean coast of Israel. Our previous investigation of this site in 2013–2014 using foraminiferal single-chamber LA-ICPMS created a large dataset consisting of HM measurements of two species, Lachlanella and Pararotalia calcariformata. This database was used to establish the BAL of Zn, Cu and Pb, associated with anthropogenic sources. In February 2021, a significant tar pollution event affected the entire Mediterranean coast of Israel, derived from an offshore oil spill. This event provided a unique opportunity to test the applicability of the foraminiferal BAL by comparing it to whole-shell ICPMS measurements of t...
Rising sea surface temperatures and extreme heat waves are affecting symbiont-bearing tropical ca... more Rising sea surface temperatures and extreme heat waves are affecting symbiont-bearing tropical calcifiers such as corals and Large Benthic Foraminifera (LBF). In many ecosystems, parallel to warming, global change unleashes a host of additional changes to the marine environment, and the combined effect of such multiple stressors may be far greater than those of temperature alone. One such additional stressor, positively correlated to temperature in evaporation-dominated shallow-water settings is rising salinity. Here we used laboratory culture experiments to evaluate the combined thermohaline tolerance of one of the most common LBF species and carbonate producer, Amphistegina lobifera. The experiments were done under ambient (39 psu) and modified (30, 45, 50 psu) salinities and at optimum (25 °C) and warm temperatures (32 °C). Calcification of the A. lobifera holobiont was evaluated by measuring alkalinity loss in the culturing seawater, as an indication of carbonate ion uptake. The vitality of the symbionts was determined by monitoring pigment loss of the holobiont and their photosynthetic performances by measuring dissolved oxygen. We further evaluated the growth of Peneroplis (P. pertusus and P. planatus), a Rhodophyta bearing LBF, which is known to tolerate high temperatures, under elevated salinities. The results show that the A. lobifera holobiont exhibits optimal performance at 39 psu and 25 °C, and its growth is significantly reduced upon exposure to 30, 45, 50 psu and under all 32 °C treatments. Salinity and temperature exhibit a significant interaction, with synergic effects observed in most treatments. Our results confirm that Peneroplis has a higher tolerance to elevated temperature and salinity compared to A. lobifera, implying that a further increase of salinity and temperatures may result in a regime shift from Amphistegina- to Peneroplis-dominated assemblages.
Journal of Geophysical Research: Biogeosciences, 2020
Larger benthic foraminifera (LBF) are unicellular eukaryotic calcifying organisms and an importan... more Larger benthic foraminifera (LBF) are unicellular eukaryotic calcifying organisms and an important component of tropical and subtropical modern and ancient oceanic ecosystems. They are major calcium carbonate producers and important contributors to primary production due to the photosynthetic activity of their symbiotic algae. Studies investigating the response of LBF to seawater carbonate chemistry changes are therefore essential for understanding the impact of climate changes and ocean acidification (OA) on shallow marine ecosystems. In this study, calcification, respiration, and photosynthesis of the widespread diatom‐bearing LBF Operculina ammonoides were measured in laboratory experiments that included manipulation of carbonate chemistry parameters. pH was altered while keeping dissolved inorganic carbon (DIC) constant, and DIC was altered while keeping pH constant. The results show clear vulnerability of O. ammonoides to low pH and CO32− under constant DIC conditions, and no i...
Geological Society, London, Special Publications, 2020
It is hypothesized that submarine transport of sediments down a continental slope induces physica... more It is hypothesized that submarine transport of sediments down a continental slope induces physical disintegration of pristine (non-broken) foraminiferal shells, and thus mass transport deposits should include a significant percentage of fragmented shells. To validate this hypothesis, we studied two gravity-cores from the eastern Mediterranean continental slope, offshore Israel: AM113 sampled within a landslide lobe at 848 m water depth, and AM015 located away from a landslide at 1080 m. At least one interval, c. 0.5 m thick, of heterogeneous sediments (i.e. debrite) was identified within each core. The timing of these debrites, based on biostratigraphy, oxygen isotopes and total organic carbon data, predates sapropel S1 in both cores and is contemporaneous (AM113) or slightly predates (AM015) the most recent deglaciation.We found a noticeable increase in the fragmentation of benthic and planktic foraminiferal shells through the last deglaciation and up to the base of S1. This strong...
The Eastern Mediterranean is experiencing a large-scale invasion of alien tropical species from t... more The Eastern Mediterranean is experiencing a large-scale invasion of alien tropical species from the Red Sea. This “Lessepsian invasion” began with the opening of the Suez Canal and is promoted by the ongoing oceanic warming. The environmental differences between the Red Sea and the Mediterranean act as a buffer allowing the invasion of certain species. This provides an opportunity to study the differences in temperature sensitivity between two sibling species of the cosmopolitian foraminifera Amphistegina. Both species are very common in the Red Sea. Whilest, only one is a successful invader and the other is absent in the Eastern Mediterranean. Here we show that the two species are different in their temperature sensitivity, which explains their selective invasion into the Mediterranean. These differences demonstrate that in respect to climate change resilient marine species can be distinguished by their ability to compensate for temperature changes by adjusting their physiological ...
Given their unique properties, tremendous progress is realized in the use of nanostructured mater... more Given their unique properties, tremendous progress is realized in the use of nanostructured materials for various applications. However, their incorporation and fabrication into prototypic devices remain challenging due to their limited ability to form hierarchical 3D structures through the use of large scale, low cost, and facile processes. Herein, this challenge is addressed and the growth of unique hierarchical structures is demonstrated by coating calcareous foraminiferal shells with metal oxide materials via simple and inexpensive processes conducted on a large scale. Foraminifera are highly diverse and abundant marine unicellular protists surrounded by large, ranging from 0.1 mm to more than 200 mm in size, identical porous, and complex hierarchical shells. In the present study, these hierarchal structures are investigated in electrochemical water oxidation reactions and tested in terms of their ability to purify water from inorganic (metal ions) contaminates. The remarkable p...
In order to establish environmentally sustainable industries there is a need for high-resolution ... more In order to establish environmentally sustainable industries there is a need for high-resolution temporal and spatial monitoring of heavy metal pollutants even at low concentrations before they become hazardous for local ecosystems. Here we present single chamber records of Cu, Zn and Pb in shells of two benthic foraminifera species with different shell types from two shallow coastal stations in Israel: An area adjacent to an electrical power plant and desalination factory (Hadera) and an industrially free nature reserve (Nachsholim). Records of both foraminifera species show elevated metal concentrations in Hadera clearly identifying the footprint of the local industrial facilities. Moreover, short-term events of elevated Cu and Pb concentrations were detected by single chamber analyses. This study demonstrates the potential of using heavy metals anomalies in foraminiferal single chambers as a tool for detecting the industrial footprint of coastal facilities as well as short term e...
Bleaching, the loss of algal symbionts, occurs in marine photosymbiotic organisms at water temper... more Bleaching, the loss of algal symbionts, occurs in marine photosymbiotic organisms at water temperatures minimally exceeding average summer SST (sea surface temperatures). Pre-adaptation allows organisms to persist under warmer conditions, providing the tolerance can be carried to new habitats. Here we provide evidence for the existence of such adaptation in the benthic foraminifera Pararotalia calcariformata. This species occurs at a thermally polluted site in the Mediterranean, where water temperatures reach a maxima daily average of 36 °C during the summer. To test whether this occurrence represents a widespread adaptation, we conducted manipulative experiments exposing this species from an unpolluted site to elevated temperatures (20–42 °C). It was kept in co-culture with the more thermally sensitive foraminifera Amphistegina lobifera in two experiments (20–36 °C). Reduced photosynthetic activity in A. lobifera occurred at 32 °C whereas photochemical stress in P. calcariformata w...
Persistent thermohaline pollution at a site along the northern coast of Israel, due to power and ... more Persistent thermohaline pollution at a site along the northern coast of Israel, due to power and desalination plants, is used as a natural laboratory to evaluate the effects of rising temperature and salinity levels on benthic foraminifera living in shallow hard-bottom habitats. Biomonitoring of the disturbed area and a control station shows that elevated temperature is a more significant stressor compared to salinity, thus causing a decrease in abundance and richness. Critical temperature thresholds were observed at 30 and 35°C, the latter representing the most thermally tolerant species in the studied area Pararotalia calcariformata, which is the only symbiont-bearing species observed within the core of the heated area. Common species of the shallow hard-bottom habitats including several Lessepsian invaders are almost absent in the most exposed site indicating that excess warming will likely impede the survival of these species that currently benefit from the ongoing warming of th...
The late Maastrichtian to early Danian at Mishor Rotem, Israel, was examined based on geochemistr... more The late Maastrichtian to early Danian at Mishor Rotem, Israel, was examined based on geochemistry, bulk rock and clay mineralogies, biostratigraphy and lithology. This section contains four red clay layers of suspect impact or volcanic origin interbedded in chalk and marly chalks. PGE anomalies indicate that only the K/T boundary red layer has an Ir dominated PGE anomaly indicative of an impact source. The late Maastrichtian red clays have Pd dominated PGE anomalies which coincide with increased trace elements of terrigenous and volcanogenic origins. Deccan or Syrian-Turkey arc volcanism is the likely source of volcanism in these clay layers. Glauconite, goethite and translucent amber spherules are present in the clay layers, but the Si-rich spherules reported by Rosenfeld et al. [l989] could not be confirmed. The absence of Cheto smectite indicates that no altered impact glass has been present. The red layers represent condensed sedimentation on topographic highs during sea level ...
One of the challenges in monitoring the marine coastal environments is quantifying the magnitude ... more One of the challenges in monitoring the marine coastal environments is quantifying the magnitude and duration of pollution events. This study introduces a new concept of defining heavy metal (HM) baseline assessment levels (BALs) in coastal environments using foraminiferal shells. We demonstrated the potential of this approach by examining a nature reserve along the Mediterranean coast of Israel. Our previous investigation of this site in 2013–2014 using foraminiferal single-chamber LA-ICPMS created a large dataset consisting of HM measurements of two species, Lachlanella and Pararotalia calcariformata. This database was used to establish the BAL of Zn, Cu and Pb, associated with anthropogenic sources. In February 2021, a significant tar pollution event affected the entire Mediterranean coast of Israel, derived from an offshore oil spill. This event provided a unique opportunity to test the applicability of the foraminiferal BAL by comparing it to whole-shell ICPMS measurements of t...
Rising sea surface temperatures and extreme heat waves are affecting symbiont-bearing tropical ca... more Rising sea surface temperatures and extreme heat waves are affecting symbiont-bearing tropical calcifiers such as corals and Large Benthic Foraminifera (LBF). In many ecosystems, parallel to warming, global change unleashes a host of additional changes to the marine environment, and the combined effect of such multiple stressors may be far greater than those of temperature alone. One such additional stressor, positively correlated to temperature in evaporation-dominated shallow-water settings is rising salinity. Here we used laboratory culture experiments to evaluate the combined thermohaline tolerance of one of the most common LBF species and carbonate producer, Amphistegina lobifera. The experiments were done under ambient (39 psu) and modified (30, 45, 50 psu) salinities and at optimum (25 °C) and warm temperatures (32 °C). Calcification of the A. lobifera holobiont was evaluated by measuring alkalinity loss in the culturing seawater, as an indication of carbonate ion uptake. The vitality of the symbionts was determined by monitoring pigment loss of the holobiont and their photosynthetic performances by measuring dissolved oxygen. We further evaluated the growth of Peneroplis (P. pertusus and P. planatus), a Rhodophyta bearing LBF, which is known to tolerate high temperatures, under elevated salinities. The results show that the A. lobifera holobiont exhibits optimal performance at 39 psu and 25 °C, and its growth is significantly reduced upon exposure to 30, 45, 50 psu and under all 32 °C treatments. Salinity and temperature exhibit a significant interaction, with synergic effects observed in most treatments. Our results confirm that Peneroplis has a higher tolerance to elevated temperature and salinity compared to A. lobifera, implying that a further increase of salinity and temperatures may result in a regime shift from Amphistegina- to Peneroplis-dominated assemblages.
Journal of Geophysical Research: Biogeosciences, 2020
Larger benthic foraminifera (LBF) are unicellular eukaryotic calcifying organisms and an importan... more Larger benthic foraminifera (LBF) are unicellular eukaryotic calcifying organisms and an important component of tropical and subtropical modern and ancient oceanic ecosystems. They are major calcium carbonate producers and important contributors to primary production due to the photosynthetic activity of their symbiotic algae. Studies investigating the response of LBF to seawater carbonate chemistry changes are therefore essential for understanding the impact of climate changes and ocean acidification (OA) on shallow marine ecosystems. In this study, calcification, respiration, and photosynthesis of the widespread diatom‐bearing LBF Operculina ammonoides were measured in laboratory experiments that included manipulation of carbonate chemistry parameters. pH was altered while keeping dissolved inorganic carbon (DIC) constant, and DIC was altered while keeping pH constant. The results show clear vulnerability of O. ammonoides to low pH and CO32− under constant DIC conditions, and no i...
Geological Society, London, Special Publications, 2020
It is hypothesized that submarine transport of sediments down a continental slope induces physica... more It is hypothesized that submarine transport of sediments down a continental slope induces physical disintegration of pristine (non-broken) foraminiferal shells, and thus mass transport deposits should include a significant percentage of fragmented shells. To validate this hypothesis, we studied two gravity-cores from the eastern Mediterranean continental slope, offshore Israel: AM113 sampled within a landslide lobe at 848 m water depth, and AM015 located away from a landslide at 1080 m. At least one interval, c. 0.5 m thick, of heterogeneous sediments (i.e. debrite) was identified within each core. The timing of these debrites, based on biostratigraphy, oxygen isotopes and total organic carbon data, predates sapropel S1 in both cores and is contemporaneous (AM113) or slightly predates (AM015) the most recent deglaciation.We found a noticeable increase in the fragmentation of benthic and planktic foraminiferal shells through the last deglaciation and up to the base of S1. This strong...
The Eastern Mediterranean is experiencing a large-scale invasion of alien tropical species from t... more The Eastern Mediterranean is experiencing a large-scale invasion of alien tropical species from the Red Sea. This “Lessepsian invasion” began with the opening of the Suez Canal and is promoted by the ongoing oceanic warming. The environmental differences between the Red Sea and the Mediterranean act as a buffer allowing the invasion of certain species. This provides an opportunity to study the differences in temperature sensitivity between two sibling species of the cosmopolitian foraminifera Amphistegina. Both species are very common in the Red Sea. Whilest, only one is a successful invader and the other is absent in the Eastern Mediterranean. Here we show that the two species are different in their temperature sensitivity, which explains their selective invasion into the Mediterranean. These differences demonstrate that in respect to climate change resilient marine species can be distinguished by their ability to compensate for temperature changes by adjusting their physiological ...
Given their unique properties, tremendous progress is realized in the use of nanostructured mater... more Given their unique properties, tremendous progress is realized in the use of nanostructured materials for various applications. However, their incorporation and fabrication into prototypic devices remain challenging due to their limited ability to form hierarchical 3D structures through the use of large scale, low cost, and facile processes. Herein, this challenge is addressed and the growth of unique hierarchical structures is demonstrated by coating calcareous foraminiferal shells with metal oxide materials via simple and inexpensive processes conducted on a large scale. Foraminifera are highly diverse and abundant marine unicellular protists surrounded by large, ranging from 0.1 mm to more than 200 mm in size, identical porous, and complex hierarchical shells. In the present study, these hierarchal structures are investigated in electrochemical water oxidation reactions and tested in terms of their ability to purify water from inorganic (metal ions) contaminates. The remarkable p...
In order to establish environmentally sustainable industries there is a need for high-resolution ... more In order to establish environmentally sustainable industries there is a need for high-resolution temporal and spatial monitoring of heavy metal pollutants even at low concentrations before they become hazardous for local ecosystems. Here we present single chamber records of Cu, Zn and Pb in shells of two benthic foraminifera species with different shell types from two shallow coastal stations in Israel: An area adjacent to an electrical power plant and desalination factory (Hadera) and an industrially free nature reserve (Nachsholim). Records of both foraminifera species show elevated metal concentrations in Hadera clearly identifying the footprint of the local industrial facilities. Moreover, short-term events of elevated Cu and Pb concentrations were detected by single chamber analyses. This study demonstrates the potential of using heavy metals anomalies in foraminiferal single chambers as a tool for detecting the industrial footprint of coastal facilities as well as short term e...
Bleaching, the loss of algal symbionts, occurs in marine photosymbiotic organisms at water temper... more Bleaching, the loss of algal symbionts, occurs in marine photosymbiotic organisms at water temperatures minimally exceeding average summer SST (sea surface temperatures). Pre-adaptation allows organisms to persist under warmer conditions, providing the tolerance can be carried to new habitats. Here we provide evidence for the existence of such adaptation in the benthic foraminifera Pararotalia calcariformata. This species occurs at a thermally polluted site in the Mediterranean, where water temperatures reach a maxima daily average of 36 °C during the summer. To test whether this occurrence represents a widespread adaptation, we conducted manipulative experiments exposing this species from an unpolluted site to elevated temperatures (20–42 °C). It was kept in co-culture with the more thermally sensitive foraminifera Amphistegina lobifera in two experiments (20–36 °C). Reduced photosynthetic activity in A. lobifera occurred at 32 °C whereas photochemical stress in P. calcariformata w...
Persistent thermohaline pollution at a site along the northern coast of Israel, due to power and ... more Persistent thermohaline pollution at a site along the northern coast of Israel, due to power and desalination plants, is used as a natural laboratory to evaluate the effects of rising temperature and salinity levels on benthic foraminifera living in shallow hard-bottom habitats. Biomonitoring of the disturbed area and a control station shows that elevated temperature is a more significant stressor compared to salinity, thus causing a decrease in abundance and richness. Critical temperature thresholds were observed at 30 and 35°C, the latter representing the most thermally tolerant species in the studied area Pararotalia calcariformata, which is the only symbiont-bearing species observed within the core of the heated area. Common species of the shallow hard-bottom habitats including several Lessepsian invaders are almost absent in the most exposed site indicating that excess warming will likely impede the survival of these species that currently benefit from the ongoing warming of th...
The late Maastrichtian to early Danian at Mishor Rotem, Israel, was examined based on geochemistr... more The late Maastrichtian to early Danian at Mishor Rotem, Israel, was examined based on geochemistry, bulk rock and clay mineralogies, biostratigraphy and lithology. This section contains four red clay layers of suspect impact or volcanic origin interbedded in chalk and marly chalks. PGE anomalies indicate that only the K/T boundary red layer has an Ir dominated PGE anomaly indicative of an impact source. The late Maastrichtian red clays have Pd dominated PGE anomalies which coincide with increased trace elements of terrigenous and volcanogenic origins. Deccan or Syrian-Turkey arc volcanism is the likely source of volcanism in these clay layers. Glauconite, goethite and translucent amber spherules are present in the clay layers, but the Si-rich spherules reported by Rosenfeld et al. [l989] could not be confirmed. The absence of Cheto smectite indicates that no altered impact glass has been present. The red layers represent condensed sedimentation on topographic highs during sea level ...
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