scholarly journals The impact of African aridity on the isotopic signature of Atlantic deep waters across the Middle Pleistocene Transition

2012 ◽  
Vol 77 (1) ◽  
pp. 182-191 ◽  
Author(s):  
Bruno Malaizé ◽  
Elsa Jullien ◽  
Amandine Tisserand ◽  
Charlotte Skonieczny ◽  
E. Francis Grousset ◽  
...  
Keyword(s):  
Deep Water ◽  
Benthic Foraminifera ◽  
Environmental Changes ◽  
Phase Relationship ◽  
Isotopic Signature ◽  
Middle Pleistocene ◽  
Time Interval ◽  
Deep Waters ◽  
Time Period ◽  
The Impact

A high resolution analysis of benthic foraminifera as well as of aeolian terrigenous proxies extracted from a 37 m-long marine core located off the Mauritanian margin spanning the last ~ 1.2 Ma, documents the possible link between major continental environmental changes with a shift in the isotopic signature of deep waters around 1.0–0.9 Ma, within the so-called Mid-Pleistocene Transition (MPT) time period. The increase in the oxygen isotopic composition of deep waters, as seen through the benthic foraminifera δ18O values, is consistent with the growth of larger ice sheets known to have occurred during this transition. Deep-water mass δ13C changes, also estimated from benthic foraminifera, show a strong depletion for the same time interval. This drastic change in δ13C values is concomitant with a worldwide 0.3‰ decrease observed in the major deep oceanic waters for the MPT time period. The phase relationship between aeolian terrigeneous signal increase and this δ13C decrease in our record, as well as in other paleorecords, supports the hypothesis of a global aridification amongst others processes to explain the deep-water masses isotopic signature changes during the MPT. In any case, the isotopic shifts imply major changes in the end-member δ18O and δ13C values of deep waters.

scholarly journals Cribrilinid bryozoans from Pleistocene Mediterranean deep-waters, with the description of new species

2020 ◽  
pp. 1-23
Author(s):  
Antonietta Rosso ◽  
Emanuela Di Martino ◽  
Andrew N. Ostrovsky
Keyword(s):  
New Species ◽  
Deep Water ◽  
Time Interval ◽  
New Combinations ◽  
Mediterranean Species ◽  
Growth Morphology ◽  
Deep Waters ◽  
First Time

Abstract Cribrilinid bryozoans originating from Pleistocene deep-water sediments from two localities near Messina (Sicily, Italy)—Capo Milazzo (Gelasian) and Scoppo (Calabrian)—were examined. Five cribrilinid species were found, three in each locality and time interval, with only one species shared. Three species, Cribrilaria profunda n. sp., Glabrilaria transversocarinata n. sp., and Figularia spectabilis n. sp., are new to science. Of the two remaining species, Figularia figularis was already known from local fossil associations, whereas Glabrilaria pedunculata, a present-day Mediterranean species, is recorded for the first time as a fossil. New combinations are suggested for two species previously assigned to Puellina, Cribrilaria saldanhai (Harmelin, 2001) n. comb. and Cribrilaria mikelae (Harmelin, 2006) n. comb. The diagnosis of the genus Figularia was amended to include an erect growth morphology in addition to the encrusting form, and the occurrence of ooecia formed by the distal kenozooid. Following a literature revision of all species currently assigned to Figularia, the new combinations Vitrimurella capitifera (Canu and Bassler, 1929) n. comb. and Hayamiellina quaylei (Powell, 1967a) n. comb. are suggested, and problematic species are listed and briefly discussed. UUID: http://zoobank.org/b7b36152-bf7b-4e00-b6ec-2614b2a58f1b

scholarly journals Environmental variations in a semi-enclosed embayment (Amvrakikos Gulf, Greece) – reconstructions based on benthic foraminifera abundance and lipid biomarker pattern

2012 ◽  
Vol 9 (6) ◽  
pp. 7405-7441 ◽  
Author(s):  
S. Naeher ◽  
M. Geraga ◽  
G. Papatheodorou ◽  
G. Ferentinos ◽  
E. Kaberi ◽  
...  
Keyword(s):  
Benthic Foraminifera ◽  
Environmental Changes ◽  
Sampling Site ◽  
Bacterial Biomass ◽  
Benthic Assemblages ◽  
Lipid Biomarker ◽  
Biomarker Pattern ◽  
Bottom Waters ◽  
Oxygen Monitoring ◽  
The Impact

Abstract. The evolution of environmental changes during the last decades and the impact on the living biomass in the western part of Amvrakikos Gulf was investigated using abundances of benthic foraminifera and lipid biomarker concentrations. These proxies indicated that the gulf has dramatically changed due to eutrophication. Eutrophication has led to a higher productivity, a higher bacterial biomass, shifts towards opportunistic and tolerant benthic foraminifera species (e.g. B. elongata, N. turgida, T. agglutinans, A. tepida) and a lower benthic species density. Close to the Preveza Straits (connection between the gulf and the Ionian Sea), the benthic assemblages appeared to be less productive and more diversified under more oxygenated conditions. Sea grass meadows largely contributed to the organic matter at this sampling site. Isorenieratane, chlorobactane and lycopane together with oxygen monitoring data indicated that anoxic (and partly euxinic) conditions prevailed seasonally throughout the western part of the gulf with more severe hypoxia towards the east. Increased surface water temperatures have led to a higher stratification, which reduced oxygen resupply to bottom waters. These developments are reasons for mass mortality events and ecosystem decline observed in Amvrakikos Gulf.

Multiple crises before the big crisis: Early Messinian Eastern Mediterranean paleoclimate reconstruction inferred from biomarkers and stable isotopes (Crete, Greece)

2021 ◽  
Author(s):  
Geanina-Adriana Butiseaca ◽  
Marcel T. J. van der Meer ◽  
Giorgos Kontakiotis ◽  
Konstantina Agiadi ◽  
Assimina Antonarakou ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Eastern Mediterranean ◽  
Dynamic Environment ◽  
Tectonic Activity ◽  
Time Interval ◽  
Alkaline Soils ◽  
Climate Conditions ◽  
Biomarker Analysis ◽  
The Mediterranean ◽  
The Impact

<p>Messinian Mediterranean (7.24‒5.33 Ma) was a highly dynamic environment governed by global climatic and regional tectonic activity. The impact of these two environmental factors is highly distinguishable especially during the latest Messinian (5.97–5.33 Ma), when the famous Messinian salinity crisis (MSC) affected the Mediterranean realm. However, the interplay between climate and tectonics is less studied for the earliest Messinian. Here we use biomarker analysis, coupled with compound-specific hydrogen (δ<sup>2</sup>H) and carbon isotopes (δ<sup>13</sup>C), to track changes in the hydrological budget, mean annual air temperature (MAAT), vegetation and reconstruct the sea-land climate conditions in Eastern Mediterranean between 7.2‒6.5 Ma. Our data from Agios Myron section on Crete (Greece) confirms a series of drastic environmental changes in the Eastern Mediterranean during the mentioned time interval. δ<sup>2</sup>H values of alkenones indicate highly evaporitic events accompanied by shifts in vegetation, from dominant >C<sub>3</sub> plants to marked increasing dominance of C<sub>4</sub>, with recurrence of C<sub>3</sub> vegetation at ~6.99 and 6.78 Ma respectively. The MAAT data indicate average values of 14⁰C and the overall trend suggests an orbitally paced continental climate, with maximum temperatures registered during eccentricity maxima. The reconstructed paleo-soil pH record follows a stepwise increasing trend towards slightly-alkaline soils, supporting an enhanced open vegetation contribution resulting from the ongoing continentalisation. These results provide new insights into the Messinian environmental conditions of the Mediterranean Sea, suggesting an ongoing restriction after 7 Ma, with multiple restrictive phases marked by increasing intensity until the final MSC event.</p>

scholarly journals Environmental variations in a semi-enclosed embayment (Amvrakikos Gulf, Greece) – reconstructions based on benthic foraminifera abundance and lipid biomarker pattern

2012 ◽  
Vol 9 (12) ◽  
pp. 5081-5094 ◽  
Author(s):  
S. Naeher ◽  
M. Geraga ◽  
G. Papatheodorou ◽  
G. Ferentinos ◽  
H. Kaberi ◽  
...  
Keyword(s):  
Benthic Foraminifera ◽  
Environmental Changes ◽  
Sampling Site ◽  
Bacterial Biomass ◽  
Oxygen Depletion ◽  
Benthic Assemblages ◽  
Lipid Biomarker ◽  
Biomarker Pattern ◽  
Oxygen Monitoring ◽  
The Impact

Abstract. The evolution of environmental changes during the last decades and the impact on the living biomass in the western part of Amvrakikos Gulf was investigated using abundances and species distributions of benthic foraminifera and lipid biomarker concentrations. These proxies indicated that the gulf has markedly changed due to eutrophication. Eutrophication has led to a higher productivity, a higher bacterial biomass, shifts towards opportunistic and tolerant benthic foraminifera species (e.g. Bulimina elongata, Nonionella turgida, Textularia agglutinans, Ammonia tepida) and a lower benthic species density. Close to the Preveza Strait (connection between the gulf and the Ionian Sea), the benthic assemblages were more diversified under more oxygenated conditions. Sea grass meadows largely contributed to the organic matter at this sampling site. The occurrence of isorenieratane, chlorobactane and lycopane supported by oxygen monitoring data indicated that anoxic (and partly euxinic) conditions prevailed seasonally throughout the western part of the gulf with more severe oxygen depletion towards the east. Increased surface water temperatures have led to a higher stratification, which reduced oxygen resupply to bottom waters. Altogether, these developments led to mass mortality events and ecosystem decline in Amvrakikos Gulf.

scholarly journals Biotic and environmental changes in the Panthalassa Ocean across the Norian (Late Triassic) impact event

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Honami Sato ◽  
Yutaro Takaya ◽  
Kazutaka Yasukawa ◽  
Koichiro Fujinaga ◽  
Tetsuji Onoue ◽  
...  
Keyword(s):  
Chemical Weathering ◽  
Environmental Changes ◽  
Upper Triassic ◽  
Late Triassic ◽  
Time Interval ◽  
Impact Event ◽  
Central Japan ◽  
Burial Flux ◽  
Bedded Chert ◽  
The Impact

Abstract Stratigraphic records of impact ejecta preserved in a pelagic deep-sea setting occur within Upper Triassic successions of the subduction-generated accretionary complexes of central Japan. A significant biotic turnover in radiolarians occurred during the ~ 300 kyr time interval after the impact event, which is characterized by a remarkable reduction in the burial flux of radiolarian silica. However, the nature of the environmental conditions at this time remains unclear. To investigate the environmental changes that triggered a decline in radiolarian burial flux after the impact event, geochemical proxies (major, trace, and rare earth elements) were applied to the middle–upper Norian (Upper Triassic) bedded chert succession of the Mino Belt, central Japan. A progressive environmental deterioration is evident from (1) a post-impact shutdown of burial flux of primary and silica- and apatite-secreting organisms; and (2) a subsequent abrupt increase in chemical weathering associated with a sustained reduction in the burial flux of radiolarian silica. No significant redox changes were observed across the impact event. The continental weathering proxies suggest a transient increase in weathering intensity occurred during the decline of radiolarian burial flux, likely in response to a short-term warm and humid period. Our results delineate a remarkable record of progressive environmental changes in the Panthalassa Ocean after this large impact event.

Benthic foraminiferal zonation in deep-water carbonate platform margin environments, northern Little Bahama Bank

1988 ◽  
Vol 62 (01) ◽  
pp. 1-8 ◽  
Author(s):  
Ronald E. Martin
Keyword(s):  
Deep Water ◽  
Benthic Foraminifera ◽  
Carbonate Platform ◽  
Sedimentary Facies ◽  
Depositional Environments ◽  
Near Surface ◽  
Sediment Gravity Flows ◽  
Gravity Flows ◽  
Platform Margin ◽  
Water Carbonate

The utility of benthic foraminifera in bathymetric interpretation of clastic depositional environments is well established. In contrast, bathymetric distribution of benthic foraminifera in deep-water carbonate environments has been largely neglected. Approximately 260 species and morphotypes of benthic foraminifera were identified from 12 piston core tops and grab samples collected along two traverses 25 km apart across the northern windward margin of Little Bahama Bank at depths of 275-1,135 m. Certain species and operational taxonomic groups of benthic foraminifera correspond to major near-surface sedimentary facies of the windward margin of Little Bahama Bank and serve as reliable depth indicators. Globocassidulina subglobosa, Cibicides rugosus, and Cibicides wuellerstorfi are all reliable depth indicators, being most abundant at depths >1,000 m, and are found in lower slope periplatform aprons, which are primarily comprised of sediment gravity flows. Reef-dwelling peneroplids and soritids (suborder Miliolina) and rotaliines (suborder Rotaliina) are most abundant at depths <300 m, reflecting downslope bottom transport in proximity to bank-margin reefs. Small miliolines, rosalinids, and discorbids are abundant in periplatform ooze at depths <300 m and are winnowed from the carbonate platform. Increased variation in assemblage diversity below 900 m reflects mixing of shallow- and deep-water species by sediment gravity flows.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

Epigenetic Studies in Psychotherapy: A Systematic Review

2020 ◽  
Vol 16 (2) ◽  
pp. 86-92
Author(s):  
Rafael Penadés ◽  
Bárbara Arias ◽  
Mar Fatjó-Vilas ◽  
Laura González-Vallespí ◽  
Clemente García-Rizo ◽  
...  
Keyword(s):  
Systematic Review ◽  
Dna Methylation ◽  
Mental Disorders ◽  
Epigenetic Modifications ◽  
Symptom Improvement ◽  
Epigenetic Changes ◽  
Main Hypothesis ◽  
Psychological Treatments ◽  
Time Period ◽  
The Impact

Background: Epigenetic modifications appear to be dynamic and they might be affected by environmental factors. The possibility of influencing these processes through psychotherapy has been suggested. Objective: To analyse the impact of psychotherapy on epigenetics when applied to mental disorders. The main hypothesis is that psychological treatments will produce epigenetic modifications related to the improvement of treated symptoms. Methods: A computerised and systematic search was completed throughout the time period from 1990 to 2019 on the PubMed, ScienceDirect and Scopus databases. Results: In total, 11 studies were selected. The studies were evaluated for the theoretical framework, genes involved, type of psychotherapy and clinical challenges and perspectives. All studies showed detectable changes at the epigenetic level, like DNA methylation changes, associated with symptom improvement after psychotherapy. Conclusion: Methylation profiles could be moderating treatment effects of psychotherapy. Beyond the detected epigenetic changes after psychotherapy, the epigenetic status before the implementation could act as an effective predictor of response.

Utilization of remote sensing for estimation of scale of cutting and growing of forest zones

2017 ◽  
Vol 920 (2) ◽  
pp. 57-60
Author(s):  
F.E. Guliyeva
Keyword(s):  
Remote Sensing ◽  
Fixed Time ◽  
Time Interval ◽  
Time Points ◽  
Average Value ◽  
Time Period ◽  
Remote Estimation ◽  
The Given ◽  
Forest Cutting

The study of results of relevant works on remote sensing of forests has shown that the known methods of remote estimation of forest cuts and growth don’t allow to calculate the objective average value of forests cut volume during the fixed time period. The existing mathematical estimates are not monotonous and make it possible to estimate primitively the scale of cutting by computing the ratio of data in two fixed time points. In the article the extreme properties of the considered estimates for deforestation and reforestation models are researched. The extreme features of integrated averaged values of given estimates upon limitations applied on variables, characterizing the deforestation and reforestation processes are studied. The integrated parameter, making it possible to calculate the averaged value of estimates of forest cutting, computed for all fixed time period with a fixed step is suggested. It is shown mathematically that the given estimate has a monotonous feature in regard of value of given time interval and make it possible to evaluate objectively the scales of forest cutting.

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