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Abrupt climate changes of the last deglaciation detected in a Western Mediterranean forest record
(2010)
Abrupt changes in Western Mediterranean climate during the last deglaciation (20 to 6 cal ka BP) are detected in marine core MD95-2043 (Alboran Sea) through the investigation of high-resolution pollen data and pollen-based climate reconstructions by the modern analogue technique (MAT) for annual precipitation (Pann) and mean temperatures of the coldest and warmest months (MTCO and MTWA). Changes in temperate Mediterranean forest development and composition and MAT reconstructions indicate major climatic shifts with parallel temperature and precipitation changes at the onsets of Heinrich stadial 1 (equivalent to the Oldest Dryas), the Bölling-Allerød (BA), and the Younger Dryas (YD). Multi-centennial-scale oscillations in forest development occurred throughout the BA, YD, and early Holocene. Shifts in vegetation composition and (Pann reconstructions indicate that forest declines occurred during dry, and generally cool, episodes centred at 14.0, 13.3, 12.9, 11.8, 10.7, 10.1, 9.2, 8.3 and 7.4 cal ka BP. The forest record also suggests multiple, low-amplitude Preboreal (PB) climate oscillations, and a marked increase in moisture availability for forest development at the end of the PB at 10.6 cal ka BP. Dry atmospheric conditions in the Western Mediterranean occurred in phase with Lateglacial events of high-latitude cooling including GI-1d (Older Dryas), GI-1b (Intra-Allerød Cold Period) and GS-1 (YD), and during Holocene events associated with high-latitude cooling, meltwater pulses and N. Atlantic ice-rafting. A possible climatic mechanism for the recurrence of dry intervals and an opposed regional precipitation pattern with respect to Western-central Europe relates to the dynamics of the westerlies and the prevalence of atmospheric blocking highs. Comparison of radiocarbon and ice-core ages for well-defined climatic transitions in the forest record suggests possible enhancement of marine reservoir ages in the Alboran Sea by 200 years (surface water age 600 years) during the Lateglacial.
Until now, the NW Indian Ocean was sparsely covered with coral proxy records, and records from the Maldives Archipelago do not exist. The first such coral proxy record from the central Maldives is presented in this study. It originates from a massive Porites lutea (Quoy and Gaimard, 1833) colony that was sampled March 2007 in the lagoon of Rasdhoo Atoll (4°N/ 73°W), which is located in the central Maldives. The record spans a period of 90 yrs and reaches back to 1917 AD with monthly to bimonthly resolution. This study investigates temporal variations of the skeletal stable oxygen (delta18O) and carbon (delta13C) isotopes, the strontium-to-calcium (Sr/Ca), and the annual extension-rates, and their relationship to historical climate variations 1917-2007. Annual extension-rates show an increase over the 20th century, and are correlated with instrumental sea surface temperatures (SST). The interannual variation of the extension-rates within 2.5-4 years is driven by the El Niño-Southern Oscillation (ENSO). The amount of skeletal extension during the summer months is triggered by variations in the strength of the SW monsoon. Interannual and decadal variability in monsoon current activity (18-19 yrs) and rainfall over India are an expression of the summer monsoon strength. This is the reason why a statistical link between coral extension-rates and precipitation over India can be established. This implies that annual extension-rates in corals can be used as a new proxy for Indian monsoon variability on decadal resolution. The delta18O record exhibits the 20th century warming trend that is influenced by the effect of monsoon-induced cooling. delta18O also reveals interannual ENSO triggered variability, which is due to ENSO-forced variations in SST and sea surface salinity (SSS). A decadal variation at 12-14 yrs cannot be linked to SST variations in the NW Indian Ocean, but with decadal variations of SSS. They could be caused by ENSO- forced variations of the monsoon currents during the mature phase of ENSO teleconnections in the Indian Ocean in boreal winter. The Sr/Ca record does not indicate a significant warming, in spite of the observed SST rise at the sampling site. Changes in seawater Sr/Ca cannot be excluded. Nevertheless, interannual ENSO forcing is still evident. Evidence for the Pacific Decadal Oscillation (PDO) is found during 1917-1955. Afterwards, the Sr/Ca data indicate the disappearance of PDO forcing. By the combination of Sr/Ca and delta18O it is possible to detect ~80% of historical El Niño and La Niña events at the sample site. This study confirms the notion that interannual to multi-decadal climate fluctuations in the Pacific play a crucial role for climate variability in the Indian Ocean.
Global-scale information on natural river flows and anthropogenic river flow alterations is required to identify areas where aqueous ecosystems are expected to be strongly degraded. Such information can support the identification of environmental flow guidelines and a sustainable water management that balances the water demands of humans and ecosystems. This study presents the first global assessment of the anthropogenic alteration of river flow regimes, in particular of flow variability, by water withdrawals and dams/reservoirs. Six ecologically relevant flow indicators were quantified using an improved version of the global water model WaterGAP. WaterGAP simulated, with a spatial resolution of 0.5 degree, river discharge as affected by human water withdrawals and dams around the year 2000, as well as naturalized discharge without this type of human interference. Compared to naturalized conditions, long-term average global discharge into oceans and internal sinks has decreased by 2.7% due to water withdrawals, and by 0.8% due to dams. Mainly due to irrigation, long-term average river discharge and statistical low flow Q90 (monthly river discharge that is exceeded in 9 out of 10 months) have decreased by more than 10% on one sixth and one quarter of the global land area (excluding Antarctica and Greenland), respectively. Q90 has increased significantly on only 5% of the land area, downstream of reservoirs. Due to both water withdrawals and reservoirs, seasonal flow amplitude has decreased significantly on one sixth of the land area, while interannual variability has increased on one quarter of the land area mainly due to irrigation. It has decreased on only 8% of the land area, in areas downstream of reservoirs where consumptive water use is low. The impact of reservoirs is likely underestimated by our study as small reservoirs are not taken into account. Areas most affected by anthropogenic river flow alterations are the Western and Central USA, Mexico, the western coast of South America, the Mediterranean rim, Southern Africa, the semi-arid and arid countries of the Near East and Western Asia, Pakistan and India, Northern China and the Australian Murray-Darling Basin, as well as some Arctic rivers. Due to a large number of uncertainties related e.g. to the estimation of water use and reservoir operation rules, the analysis is expected to provide only first estimates of river flow alterations that should be refined in the future.
The present PhD-thesis was prepared within subproject B8 of the DFG-Sonderforschungsbereich (SFB) 641 “The Tropospheric Ice Phase”. The subproject B8 was entitled “Interactions of volatile organic compounds with airborne ice crystals”. Results of previous studies have shown that various volatile organic compounds (VOC) and semivolatile organic compounds (SVOC) are incorporated into the atmospheric ice phase and several uptake mechanisms are discussed in the literature. The aim of this study was to identify the dominating VOC and SVOC in airborne snow collected at Jungfraujoch in the Swiss Alps (3580 m asl) and to study in laboratory experiments the uptake mechanism of organic compounds into snow and ice. For this purpose an analytical method to analyse freshly fallen snow samples was developed and evaluated in a first step. The method consists of headspace (HS) solid phase dynamic extraction (SPDE) followed by gas chromatography combined with mass spectrometry (GC/MS). During the extraction process a new cooling device was successfully integrated into the HS-SPDE-GC/MS method to enhance the extraction yield. Extraction and desorption parameters such as the number of extraction cycles, extraction temperature, desorption volume and desorption flow rate have been optimized. Detection limits for benzene, toluene, ethylbenzene, m-, p-, o- xylene (BTEX) ranged from 19 ng L-1 (benzene) to 30 ng L-1 (m/p-xylene), while those for C6-C10 n-aldehydes ranged from 21 ng L-1 (n-heptanal) to 63 ng L-1 (n-hexanal). Furthermore, freshly fallen snow samples were collected at the High Altitude Research Station Jungfraujoch (3580 m asl, Switzerland) during the field campaigns “Cloud and aerosol characterization experiment” (CLACE) 4 and 5 in February and March 2005 and 2006, respectively. Freshly fallen snow samples collected directly in-cloud on a high altitude remote location were used as approximation of airborne ice crystals since sampling of airborne ice crystals in quantities sufficient for analysis of individual organic compounds is not yet possible. In the collected snow samples a wide range of organic compounds were identified, namely BTEX, n-aldehydes (C6-C10), terpenes, chlorinated hydrocarbons and alkylated monoaromatics. The most abundant organic compounds in snow samples from Jungfaujoch during CLACE 4 and 5 were n-hexanal with a median concentration of 1.324 μg L-1 (CLACE 5) followed by n-nonanal (CLACE 5) with a median concentration of 1.239 μg L-1. High concentration variations of the analytes in snow samples collected at the same time at the same place argue for a heterogeneous composition of snow and ice. Several indicators were found that the origin of the n-aldehydes in the snow can be attributed to direct biogenic emissions from vegetation and indirect biogenic emissions through photochemical oxidation of fatty acids and alkenes. In a second step laboratory experiments were carried out to clarify the uptake mechanism of volatile and semivolatile organic compounds into snow/ice. Organic compounds can be incorporated into the atmospheric ice phase either by the process of gas scavenging, liquid scavenging (riming) or particle scavenging. Gas scavenging (incorporation of the organic compounds from the gas phase during growing of ice crystals) revealed to be ineffective based on previous laboratory experiments in which ice crystals were growing in the presence of aromatic hydrocarbons (BTEX) in the gas phase. In the present study the process of liquid scavenging (riming) was investigated in the laboratory using aqueous standard solutions containing BTEX, naldehydes (C6-C10), methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE). The headspace above the standard solution was sampled after adjusting the aqueous solutions to definite temperatures by use of a thermostat. Measurement were carried out at 25°C, 15°C and 5°C (water), -5°C and -15°C (supercooled water) and -25°C (ice). Results have shown that the known trend of lower gas phase concentrations over water concomitant with lower temperatures (Henry’s Law) is only valid for temperatures above 0°C. At temperature below 0°C, increasing concentrations of the analytes (BTEX, MTBE, ETBE and n-aldehydes) were determined in the gas phase together with decreasing temperatures. Dimensionless Henry’s law coefficients (KAW) were calculated from the concentrations of the organic compounds in the headspace above the standard solutions at temperatures between 25°C and -25°C. The observed inversion of Henry’s law coefficients of volatile and semivolatile organic compounds at a water temperature of approximately 0°C is explained by the formation of ordered zones of H2O molecules in supercooled water called “ice-like-clusters”. Together with decreasing temperatures the degree of formation of ordered zones increases which results in the removal of the organic molecules from the liquid phase and transfer into the gas phase. At a temperature of -25°C the supercooled water is converted into ice and a further significant increase of the gas phase concentrations of hydrophobic compounds such as BTEX is observed. In comparison, less hydrophobic compounds such as MTBE, ETBE and n-aldehydes are detected in lower amounts in the gas phase above the water/ice phase due to the higher water solubility and lower Henry coefficients compared to BTEX. The results show that in the absence of particles the uptake of BTEX MTBE, ETBE and C6-C10-naldehydes into ice not enhanced during freezing of a supercooled liquid, since at -25°C for these analytes the concentrations in the gas phase are higher at -25°C (ice) compared with -15°C (supercooled liquid). The heterogeneous distribution of BTEX and n-aldehydes concentrations in snow samples collected during the CLACE field campaigns suggests that adsorption of the organic compounds to particles followed by incorporation of the particles into the snow and ice might play a major role in the uptake process of organic compounds into snow and ice. To increase the knowledge about uptake processes of organic compounds into snow and ice further experiments are required with should include aerosol particles in the experimental setup to evaluate the influence of particle scavenging in the uptake processes.
The ENVISAT validation programme for the atmospheric instruments MIPAS, SCIAMACHY and GOMOS is based on a number of balloon-borne, aircraft, satellite and ground-based correlative measurements. In particular the activities of validation scientists were coordinated by ESA within the ENVISAT Stratospheric Aircraft and Balloon Campaign or ESABC. As part of a series of similar papers on other species [this issue] and in parallel to the contribution of the individual validation teams, the present paper provides a synthesis of comparisons performed between MIPAS CH4 and N2O profiles produced by the current ESA operational software (Instrument Processing Facility version 4.61 or IPF v4.61, full resolution MIPAS data covering the period 9 July 2002 to 26 March 2004) and correlative measurements obtained from balloon and aircraft experiments as well as from satellite sensors or from ground-based instruments. In the middle stratosphere, no significant bias is observed between MIPAS and correlative measurements, and MIPAS is providing a very consistent and global picture of the distribution of CH4 and N2O in this region. In average, the MIPAS CH4 values show a small positive bias in the lower stratosphere of about 5%. A similar situation is observed for N2O with a positive bias of 4%. In the lower stratosphere/upper troposphere (UT/LS) the individual used MIPAS data version 4.61 still exhibits some unphysical oscillations in individual CH4 and N2O profiles caused by the processing algorithm (with almost no regularization). Taking these problems into account, the MIPAS CH4 and N2O profiles are behaving as expected from the internal error estimation of IPF v4.61 and the estimated errors of the correlative measurements.
Delthyridoid spiriferids are characterized by a global abundance and fast evolution during Silurian and Devonian, and, therefore, are used as important biostratigraphical and palaeobiogeographical tools. In this work, delthyridoid brachiopod faunas from different regions of today’s world, resp., of different palaeobiogeographical units, are compared side-by-side to investigate their phylogenetic relationships and to improve, in a second step, the palaeobiogeography from Late Silurian to Early Eifelian time. A new systematics of Delthyridoidae is established which is more complicated than hitherto assumed. The results of this study are mainly based on direct comparison of articulated and isolated brachiopod shells, external and internal moulds, as well as latex casts and serial sections. The computer supported cladistic analyses have turned out not to be useful due to different kinds of preservation resulting in an incomplete matrix which is insufficient for reliable cladograms. A further problem in terms of cladistical analyses are various convergences during the evolution of spiriferids. Many characters evolved independently from each other at different times in each lineage so that autapomorphies are hardly or not at all recognizable. As a result, families and genera are only definable by a combination of characters rather than by a single or a few autapomorphies. As a new method, 3D reconstruction from serial sections is introduced which made it possible for the first time to compare directly mouldic and shelly material. Preliminary results are presented herein. Statistical analyses of measurements taken from new taxa are made but regarded as a descriptive argument rather than a deciding factor for taxonmy due to incomplete preservation and/or tectonic deformation. Brachiopods, especially type material, from collections of different institutions and museums are studied as well as personal material, whenever possible collected from topotype outcrops. Emended diagnoses, if necessary, from family to species level are given. During this work several new taxa have been erected: 7 new families: Australospiriferidae, Murchisonispiriferidae, Orientospiriferidae, Otospiriferidae, Patriaspiriferidae, Rostrospiriferidae, and Trigonospiriferidae; 6 new genera, 1 of these in open nomenclature: Cyclopterospirifer, Hallispirifer, Parlinispirifer, Murchisonispirifer, Shujiapingensispirifer, and gen. nov. B; and 3 new species: Patriaspirifer merriami, Patriaspirifer johnsoni, and Murchisonispirifer feldmani; 1 taxon is defined as nomen novum: Orientospirifer nakaolingensis wani. In the framework of this project, 2 families: Filispiriferidae and Multispiriferidae; 1 subfamily: Multiplicatispiriferinae, 6 genera, 1 of them in open nomenclature: Frequentispirifer, Leonispirifer, Multiplicatispirifer, Ovetensispirifer, Turcispirifer, and Gen. A; and 9 new species, 3 of them in open nomenclature: Filispirifer hamadae, Leonispirifer leonensis, Multiplicatispirifer foumzguidensis, Oventensispirifer novascotianus, Quiringites arensentiae, Turcispirifer turciae, Multiplicatispirifer cf. foumzguidensis, Quiringites cf. arensentiae, and ?Turcispirifer sp. A which have already been established are also described in this work. The brachiopod faunas studied consist of externally very similar spiriferids which have been identified as same genera, species, or even subspecies in earlier times. These forms are considered as 6 distinct morphotypes Howellella-, Arduspirifer-, Acrospirifer-, Euryspirifer-, Paraspirifer-, and Multiplicatispirifer-like morphotypes, which are briefly introduced. The new systematics is characterized by different clades, the European/North African delthyridoid spiriferid clade, the North American delthyridoid spiriferid clade, the Asian delthyridoid spiriferid clade, the Malvinokaffric delthyridoid spiriferid clade, and the delthyridoid multiplicated spiriferid clade. Each of them is described in a cladistic and in a phylogenetic way. Their phylogenetic relationship sheds new light on palaeobiogeographical interpretations for the different stages from Late Silurian to early Middle Devonian time. A tendency for increasing endemicity is seen until the end of the Early Emsian, which is interrupted by short term regional faunal exchange within a province or within a realm, followed by a loss of endemicity resulting in global distribution of brachiopod genera until the end of Givetian time. The Old World Realm is re-defined due to the lack of phylogenetic relationship between its faunas and subdivided into the European Realm, consisting of the Gondwanan and Avalonian provinces, and the Asian Realm, consisting of the Siberian, Sino, and Mongolian provinces. A reconstruction of Lower Devonian palaeobiographical map is introduced.
NASAs Stardust Mission ist die erste Mission, die - nach den Apollo Missionen zum Mond - Material von einem extraterrestrischen Körper erfolgreich für die Untersuchung auf der Erde, zurückgebracht hat. Desweiteren konnten erfolgreich Proben von einem Interstellaren Partikelstrom aufgesammelt werden, der das Sonnensystem derzeit passiert. Die Mission erlaubt einen Einblick in die Beschaffenheit der Kometenpartikel, die Rolle von Kometen im Sonnensystem sowie den Eintrag von Staub in die Zodiakalwolke. Desweiteren erlaubt die Analyse der Kometenpartikel den direkten Vergleich zu bereits untersuchten Meteoriten und Interplanetaren Staub Partikeln (IDPs) die auf der Erde bzw. deren Stratosphäre gesammelt wurden. Stardust ist die vierte ”Discovery” Mission und wurde am 7. Februar 1999 gestartet. Während des Fluges zum Kometen 81P/Wild 2 wurde ein interstellarer Partikelstrom beprobt und der Asteroid Annefrank passiert. Nach fünf Jahren kam es zum Zusammentreffen mit dem Kometen 81P/Wild 2 und über fünf Minuten, wurden Proben mit einer Auffangvorrichtung eingesammelt. Es dauerte weitere zwei Jahre bis die Stardust Sonde die Proben erfolgreich zur Erde zurückgebracht hat und zur Untersuchung freigegeben wurden. Interstellare und kometare Partikel wurden mit einer tennisschlägerartigen Auffangvorrichtung eingefangen, die aus einer Vielzahl von Aerogel Zellen aufgebaut ist. Das für die Stardust Mission verwendete Aerogel besteht aus SiO2 dessen dendritische Struktur zu 99,8 % aus Luft (Poren) besteht. Dadurch erscheint es nahezu transparent, was die optische Suche mit Mikroskopen nach den Einschlagsspuren der Körner vereinfacht. Die jeweiligen Partikel wurden auf unterschiedlichen Seiten der Vorrichtung eingefangen, da unterschiedliche Eigenschaften des Aerogels notwendig waren und um sie später voneinander unterscheiden zu können. Die Seite, in der die Kometenpartikel eingefangen wurde, musste Körner mit unterschiedlichen Grössen, Morphologien und niedrigeren Geschwindigkeiten abbremsen, während auf der interstellaren Seite die Körner von wesentlich höheren Geschwindigkeiten abgebremst werden mussten. Die Aerogelzellen haben ein variierendes Dichteprofil: an der Oberfläche ist die Dichte geringer (5 mg/ml) und erhöht sich mit der Tiefe auf 30-50 mg/ml. Dieses Dichteprofil ist notwendig, da beim Einschlag der Körner auf das Auffangmedium ein hoher Druck entsteht, der umso geringer ist, je niedriger die Dichte im Moment des Auftreffens ist. Die Aerogelzellen für die Kometenpartikel haben drei Lagen mit unterschiedlichen Dichten, die Zellen für die interstellaren Körner haben zwei unterschiedliche Dichten (Tsou et al., 2003)....
The Late Tertiary to Quaternary evolution of the Ntem interior delta in SW Cameroon shall be modelled. A step fault was formed along neotectonically remobilized Precambrian structures. Uncalibrated 14C-datations in this ‘sediment trap’ show Pleistocene to Holocene ages. Both within and below the interior delta pebbles and clasts which are cemented in an iron and manganese matrix were found. These ‘fanglomerates’ are used to discuss different processes of the younger evolution also concerning climatic fluctuations in the study area.
New industries are recognized as new impetus to national wealth. At the same time, they are increasingly becoming geographically concentrated in some well defined areas. But current studies on the emergence of industrial clusters tend to analyze favorable driving factors. This dissertation takes the example of a Chinese endogenous industrial cluster, the traditional Chinese medicine (TCM) cluster at Tonghua, a small peripheral city in Northeastern China, to contribute to the theoretical understanding of the emergence of industrial cluster as a co-evolutionary process of organizations, institutions and firms, or, to put it more broadly, as economic evolution embedded in complex socio-economic contexts. The recent advance in evolutionary and co-evolutionary economics which considers the economy and economic landscape as dynamic process instead of equilibrium can be regarded as a part of broader and more intellectual turn of quest for history in social sciences. Although the principle of "history matters" is widely acknowledged, it tends to be reduced to a quite simple concept of "path dependence". However, path dependence cannot offer space for new path creation, except from an external shock. Accordingly, the role of human conscious action or Schumpeterian innovation should be added to path analysis through the concept of path creation. Furthermore, and more importantly, history should be understood as context, and historical context can be explored through the understanding of multi-paths and interaction among them over time. So path inter-dependence (co-evolution between paths) would be useful to better understand the complexity of real history. Since the industrial cluster is composed of interconnected firms and is also subject to changes in institution and technology, I will focus on the multi-way causal relationship between firm, institution and technology. The theorizing is not entirely new, but most of the theoretical and empirical discussions are at the national or industrial level, not regional or local one. A competitive cluster can be regarded as a co-evolutionary hotspot in which multiple populations actively interact and are interconnected. Co-evolution itself is a dynamic and evolutionary process. So I will adopt a dynamic and evolutionary view to examine co-evolutionary degree or co-evolutionary effects in the Tonghua pharmaceutical cluster through time. After a brief introduction which deals with the national institutional changes that are highly associated with new venture creation, entrepreneurship, and innovation, with registrations on drug and healthcare system, and with changes in market demand of China’s pharmaceutical industry and geographical distribution, I will collect evidences from three aspects based upon field survey and second hand data, i.e., the history of the enterprises, the origin of entrepreneurship, and the knowledge of evolution, linking their respective generative relationships through the genealogical method. In this volume, the evolution of the Tonghua pharmaceutical firm organization, the formation of local entrepreneurship, historical accumulation of knowledge, and particular knowledge of transfer among generations of firms will be discussed, then I will probe into co-adaption and co-evolution between local formal and informal institutions and organizations in Tonghua’s TCM industry. In addition, I will try to understand the co-evolutionary process at different geographical levels (namely, national and local). In summary, my main findings include the following several points. Firstly, in the course of the emergence of Tonghua’s pharmaceutical industry, local social networks and the traditional alliance between enterprises and government have played important roles. Secondly, the most important factor that influences the evolution of endogenous industrial clusters such as the Tonghua pharmaceutical industry in transitional countries is not the change in technology, but the change in fundamental national institutions. Thirdly, the success of the Tonghua pharmaceutical industry can be ascribed to the creation of multiple paths largely based on initial conditions, which implies that economic policy should have historical consciousness, namely, new economic innovation should make full use of both historical legacies and existing assets. Finally, it is co-adaption and co-selection of firm organization, institution, and technology that have jointly made Tonghua’s pharmaceutical industry become highly competitive, which means that whether one region can grasp new opportunities partially depends on its capabilities to coordinate a varity of development agents.
Trace elemental concentrations of bivalve shells content a wealthy of environmental and climatic information of the past, and therefore the studies of trace elemental distributions in bivalve shells gained increasing interest lately. However, after more than half century of research, most of the trace elemental variations are still not well understood and trace elemental proxies are far from being routinely applicable. This dissertation focuses on a better understanding of the trace elemental chemistry of Arctica islandica shells from Iceland, and paving the way for the application of the trace elemental proxies to reconstruct the environmental and climatic changes. Traits of trace elemental concentrations on A. islandica shells were explored and evaluated. Then based the geochemical traits of the shells, four non-environmental/climatic controlling is indentified. (1) Trace elemental concentrations of bivalve shells are effected by early diagenesis by the leach or exchange of elemental ions, especially in shell tip part, even with the protection of periostrucum; (2) The analytical methods also affect the results of trace elemental concentrations, especially for the element, such as Mg, which is highly enriched in organic matrices; (3) Shell organic matrices are found play a dominating role on the concentration of trace elements on A. islandica shells. Most trace elements only occurred in insoluble organic matrices (IOM), although others are only found in the carbonate fraction. IOM of A. islandica shells is significantly enriched in Mg, while Li and Na are more deplete in IOM, but enriched in shell carbonate. Ba is more or less even contented in IOM and shell carbonate. The concentrations of certain elements vary between primary layer and secondary layer; (4) The vital /physiological controlling on trace elemental distributions of bivalve shells is also confirmed. Six elemental (B, Na, Mg, Mn, Sr, and Ba) concentrations show significant correlation (exponential functions) with ontogenetic age and shell grow rates (logarithmic equations). It is worthy to remark that B, Mg, Sr and Ba concentrations are negatively correlated with shell growth rate, positive with ontogenetic age, while the concentrations of Na and Mn show the opposite trends. At last, all the controlling described above can be taken into account and corrected to extract the environmental and climatic signal by a kind of standardization. The derived six exponential functions of the high correlations between six trace elemental concentrations and ontogenetic year are applied to make the standardization of these element-Ca ratios. The gotten standardized indices are compared with the variations of environmental and climatic parameters in this region, and many correlations are found. Standardized indices of Sr/Ca ratios are strongly related to the sun spot number, autumn NAO, autumn Europe surface air temperature (SAT) and Arctic sea surface temperature anomaly (TA), and those of Mg/Ca ratios are strongly associated with Arctic TA, Europe SAT and Solar variation (irradiance). The variations of autumn Europe SAT demonstrated more similarity with standardized indices of B/Ca than other parameters. Except for the SAT index of Arctic, the standardized indices of Na/Ca showed no distinct relation to temperature. European precipitation and the Arctic sea level pressure index compared well the Na/Ca ratios of the shells, and so did the autumn NAO. Standardized indices of Mn/Ca were correlated with the number of hurricanes in the North Atlantic, Northern Europe SAT and sun spot number.