hopanoid hydrocarbons and perylene in lake biwa japan sediments environmental control on their abundance and molecular composition abstract we examined the vertical distribution of hopanoid hydrocarbons and perylene in sedimentary sections from lake biwa japan and discuss the results with respect to paleoenvironmental information from around the lake region over the last 120 kyr moretene concentration was high above the sections where fall out events of tephra tephra at occurred ca 30 kyr before present bp this feature suggests that the tephra fall out events created o 2 deficient conditions resulting in high activity of methane producing bacteria and of methanotrophic moretene producing bacteria becoming active above the tephra layer five sections at 10 20 kyr ca 35 kyr ca 70 kyr ca 90 kyr and ca 110 kyr bp exhibited peaks in the ratio of 17 21 22r homohopane to 17 21 22r homohopane hopc 31 the n c 23 n c 31 alkane ratio in these sections was 0 6 0 1 n 49 very low if compared with typical characteristics of n alkanes for a sphagnum peat environment n c 23 n c 31 ca 3 6 bingham et al 2010 we conclude that sphagnum peat may not have been an important contributor of n alkanes over the past 120 kyr comparison with previous pollen records for the lake region suggests that high hopc 31 values may be caused by production of acidic soil from expansion of temperate conifer e g cryptomeria forest under cold and wet climate conditions the abundance of perylene relative to sediment or total organic carbon toc was high in the sections at ca 20 kyr ca 70 kyr and ca 90 kyr bp these sections were approximately in accord with those having a maximum in hopc 31 this concordance indicates that the climatic conditions suitable for the production of perylene quinone in soil surrounding the lake coincided with those for a high hopc 31 ratio thus hopc 31 and perylene toc might be useful as proxies of soil acidity temperature and humidity

applications of organic geochemistry to paleolimnological reconstructions a summary of examples from the laurentian great lakes the organic matter content of lake sediments contains information that helps to reconstruct past environmental conditions evaluate histories of climate change and assess impacts of humans on local ecosystems the elemental isotopic and molecular compositions of organic matter buried in sediment provide evidence of the biota that have lived in a lake and its catchment area and they serve as proxies of organic matter delivery and accumulation sedimentary records from the north american great lakes provide examples of applications of organic geochemistry to paleolimnological reconstructions the records of these lakes date from retreat of the laurentide ice sheet around 12 ka include the mid holocene hypsithermal and show consequences of recent human changes low corg ntotal ratios indicate that most of the sediment organic matter in the great lakes is from algal production yet changes in biomarker molecule compositions also show that varying amounts of land plant organic matter have been delivered to the lakes elevated algal productivity that accompanies nutrient enrichments of lake waters is recorded as excursions to less negative 13c values in the organic matter of sediments that were deposited in the 1960s and 1970s increased organic carbon mass accumulation rates mirror the isotopic excursions in most parts of the great lakes accumulations of petroleum residues and pyrogenic polycyclic aromatic hydrocarbons in sediments identify fluvial and eolian delivery of organic matter components to different parts of the great lakes emerging applications of multiple and novel organic geochemical proxies to paleolimnological reconstructions are promising yet some potentially important measurements remain underutilized

concentration and character of pahs and other hydrocarbons in coals of varying rank implications for environmental studies of soils and sediments containing particulate coal abstract particulate coal can occur in soils and sediments from both natural and anthropogenic sources its presence can influence the concentrations of regulated and more bioavailable pollutants through its geosorbent qualities and its own contribution of total extractable hydrocarbons teh including polycyclic aromatic hydrocarbons pahs and biomarkers extractable pahs in coal also can potentially affect pah based source and maturity ratios of soil or sediment extracts which can be used to assess the source s of pahs this study reports on the absolute concentrations of teh the 16 priority pollutant pahs 27 alkylated pahs and sulfur containing aromatics and selected biomarkers in 15 coals ranging in rank from lignite to anthracite unlike most previous studies in the fuel science or geochemical literature the coals herein were extracted using dichloromethane at room temperature an epa method 3500 type method common in environmental laboratories thereby allowing comparison of these results to environmental studies the concentrations of teh ranged from 8 2 to 2500 g g coal dry wt with a maximum yield among high volatile bituminous coals the teh fingerprints were variable and some of these resembled those of other forms of contamination the concentrations of priority pollutant pahs ranged from 35 to 11 000 ng g coal dry wt or 38 to 12 000 ng g carbon and varied with coal rank reaching a maximum within the high volatile bituminous rank the distributions of extractable pahs and numerous pah ratios conventionally used as source and or maturity parameters also varied with coal rank emphasizing that particulate coal in soils and sediments cannot be universally represented by a single set of diagnostic parameters hopanoid and sterane biomarker yields also varied with rank reaching a maximum in high volatile bituminous coals and were low relative to pahs because particulate coal often co occurs with other sources of hydrocarbons in soils and sediments the data presented herein may prove useful in allocating coal versus non coal sources on a mass balance basis

mound development as an interaction of individual plants with soil water erosion and sedimentation processes on slopes in the mediterranean region semi natural shrubland communities named matorral often present a discontinuous cover where isolated perennial plants alternate with bare inter plant areas in such ecosystems the patchy distribution of the vegetation is usually associated with microtopographic sequences of mounds that develop under isolated plants and break the overall slope continuity in this study the influence of three representative species of the mediterranean matorral rosmarinus officinalis stipa tenacissima and anthyllis cytisoides on slope microtopography is determined and the processes that take part in the development of microtopographic structures beneath the plant canopy are identified the influence of slope gradient plant species and plant parameters on the shape and height of microtopographic structures is also studied the shape of the microtopographic structures is described by using a two dimensional microprofilemeter and mound height is determined by measuring in the field a mound height index defined as the distance from the top to the bottom of the mound the results obtained show that plant species play a major role in the shape and height of the microtopographic structures whereas terrace type structures generally develop under anthyllis shrubs microtopographic forms associated with rosmarinus and stipa plants vary with slope gradient the almost symmetric mound type structures that develop under these two species on gentle slopes change into terrace type structures as slope gradient increases moreover statistically significant differences exist between the three species with regard to mound height mean values of mound height are 19 4 14 6 and 4 3 cm under the canopy of stipa rosmarinus and anthyllis respectively plant parameters essentially roughness and slope gradient have a significant influence on mound height index four main processes were identified as affecting mound development in the studied field site sedimentation differential interrill erosion differential splash erosion and bioturbation plant species interact in different ways with these processes according to their morphologies since stipa and rosmarinus plants are more efficient than anthyllis shrubs in controlling water erosion in retaining sediments and in modifying soil properties under their respective canopies they give rise to higher microtopographic structures that facilitate water and nutrient storage by plants on slopes copyright 2000 john wiley sons ltd

a 2600 year record of past polycyclic aromatic hydrocarbons pahs deposition at holzmaar eifel germany polycyclic aromatic hydrocarbons pahs are a proxy for climate and human related historical fire activity which has rarely been used beyond 1800 ad we explored the concentration and composition patterns of pahs together with other proxies charcoal c n s 13c 15n and 34s in a sediment core of holzmaar as indicators of variations in climate and anthropogenic activity over the past 2600 years the concentrations of pyrogenic pahs remained low 500 ng g 1 from the pre roman iron age 600 bc until the first significant increases to ca 1000 1800 ng g 1 between 1700 and 1750 ad related to regional iron production the highest increases in pyrogenic pah concentrations occurred with industrialization peaking in the 1960s pah concentrations in most recent sediments decreased to pre industrial levels because of emission control measures and the switch from coal to oil and gas as major fuel sources fluxes of pahs mg km 2 yr 1 increased in the order migration period and early middle ages pre roman iron ages roman era high middle ages and renaissance pre industrial modern period industrial modern period the changes of pahs fluxes in pre industrial times parallel known changes in local regional and continental anthropogenic activity and climatic variations or their interactions across these historical periods perylene a mainly biologically produced compound was the dominant pah in pre industrial times the migration period and the early middle ages witnessed the most profound and simultaneous changes to the sedimentary organic matter properties in the past 2600 years including the lowest pah fluxes because of reduced human activity and more negative 13c and 15n values probably in response to colder and wetter conditions

record of postglacial organic matter delivery and burial in sediments of lake ontario a 12 m piston core obtained from lake ontario has allowed us to study the accumulation of organic matter in sediments deposited since the retreat of the laurentian ice sheet about 12 500 years ago discrepancies between radiocarbon dates of disseminated organic matter and ostracod shells emphasize the magnitude of the recycling and retention of organic carbon in the great lakes concentrations of caco3 and organic carbon decrease down core due to the presence of fine grained glaciolacustrine clays at the base of the sedimentary sequence increases in sediment grain size indicate periods with enhanced fluxes of terrigenous material cn ratios organic carbon and caco3 vary proportionally with fluctuations in terrigenous input cn ratios indicate that lacustrine algae have been the main source of organic matter to lake ontario sediments organic 13c values become heavier at the bottom of the core suggesting a shift in carbon sources for the bulk organic matter anthropogenic effects are well documented in total hydrocarbon and total fatty acid profiles of modern sediments whereas postglacial trends representing natural changes of organic matter are relatively undetectable sedimentary profiles of terrigenous aquatic ratios of n alkane and n alkanoic acids indicate that early variations in postglacial sedimentation rates may have impacted the preservation of aquatic organic matter changes in watershed vegetation and organic matter delivery to lake ontario altered these ratios as deglaciation progressed organic geochemical properties of modern sediments have recorded how anthropogenic activity has augmented algal productivity in lake ontario by increasing nutrient input

an aircraft based study of strong gap flows in nares strait greenland abstractgap flows and the stable boundary layer were studied in northwest greenland during the aircraft based investigation of katabatic winds and polynyas during summer ikapos experiment in june

a hypothesis for the origin of perylene based on its low abundance in sediments of green bay wisconsin abstract perylene a polycyclic aromatic hydrocarbon pah that is common in sediments is believed to originate principally from anaerobic diagenesis of organic matter but its precursor material remains enigmatic we have investigated the formation of perylene in a dated sediment core from green bay wi comparisons of sedimentary profiles of perylene anthropogenic pahs land plant derived hydrocarbons and aquatic contributions of organic matter rule out a specific industrial terrigenous or aquatic precursor for perylene instead perylene seems to be formed from any kind of organic matter as a consequence of a specific type of microbial activity in sub bottom sediments despite an abundance of organic matter the amount of perylene is low in green bay and in other organic carbon rich lake sediments the abundant availability of organic matter that stimulates microbial activity in green bay sediments would seem to favor perylene formation in such sediments we therefore hypothesize that the microorganisms responsible for perylene formation do not compete successfully with those that flourish in sediments rich in organic matter perylene formation consequently does not become significant until deeper in sediments after the more reactive types of organic matter have been consumed

a review of the biogeochemical controls on the occurrence and distribution of polycyclic aromatic compounds pacs in coals abstract the organic matter in coal contains polycyclic aromatic compounds pacs of varying quantities in diverse soluble and insoluble forms pacs in coal are of special interest for organic geochemical studies because they have been successfully used as biological marker compounds biomarkers and indicators of thermal maturity in addition they could provide critical information to understand the structural and compositional evolution of the coal organic matters during coalification and to predict pac releasing characteristics during coal utilization the main purpose of this paper is to provide a critical review on the current state of knowledge on the potential use of pac composition to understand the underlying biogeochemical factors that control pac occurrence and distribution in coal the published pac data of world coal are first compiled according to their ranks natural coke anthracite semi anthracite bituminous coal low volatile bituminous coal medium volatile bituminous coal high volatile bituminous coal sub bituminous coal lignite countries brazil canada china france germany japan usa formation periods carboniferous permian jurassic cretaceous early middle cenozoic then the biogeochemical factors affecting the occurrence and distribution of pacs in coal including biogenic precursor materials coal rank maceral composition depositional environment and geological settings are comprehensively reviewed the results show that the geochemical parameters of pacs in coal are robust tools to trace the coalification processes from the molecular perspectives and to understand the corresponding biogeochemical process e g depositional environment geological settings igneous intrusion occurring during coal formation

polynya dynamics a review of observations and modeling 1 polynyas are nonlinear shaped openings within the ice cover ranging in size from 10 to 105 km2 polynyas play an important climatic role first winter polynyas tend to warm the atmosphere thus affecting atmospheric mesoscale motions second ocean surface cooling and brine rejection during sea ice growth in polynyas lead to vertical mixing and convection contributing to the transformation of intermediate and deep waters in the global ocean and the maintenance of the oceanic overturning circulation since 1990 there has been an upsurge in polynya observations and theoretical models for polynya formation and their impact on the biogeochemistry of the polar seas this article reviews polynya research carried out in the last 2 decades focusing on presenting a state of the art picture of the physical interactions between polynyas and the atmosphere sea ice ocean system observational and modeling studies the surface heat budget and water mass transformation within these features are addressed

a coupled ice ocean model of ice breakup and banding in the marginal ice zone a coupled ice ocean numerical model for the marginal ice zone is considered the model consists of a nonlinear sea ice model and a two layer reduced gravity ocean model the dependence of the upwelling response on wind stress direction is discussed the results confirm earlier analytical work it is shown that there exist directions for which there is no upwelling while other directions give maximum upwelling in terms of the volume of uplifted water the ice and ocean is coupled directly through the stress at the ice ocean interface an interesting consequence of the coupling is found in cases when the ice edge is almost stationary in these cases the ice tends to break up a few tenths of kilometers inside of the ice edge

perylene in lake biwa sediments originating from cenococcum geophilum in its catchment area abstract perylene which is composed of five benzene rings is commonly found in sediments throughout the world at concentrations and distributions that are different from those of other polycyclic aromatic hydrocarbons the only information available on the origin of perylene comes from 4 9 dihydroxyperylene 3 10 quinone dhpq which originates from fungal component symbiosis or from parasites on plants however there is no direct evidence of a mechanism of perylene formation in this study we examined the relationship between sedimentary perylene and cenococcum geophilum c geophilum in a catchment area at lake biwa sclerotium grains of c geophilum containing dhpq were found in this catchment area approximately 40 balls kg 1 dried soil for 1 mm and small sclerotium grains were frequently found in the sediment in the sediment sample we also found broken particles containing perylene and they had a porous structure characteristic of sclerotium grains furthermore the particles contained dhpq in different transformation stages to perylene via 3 10 perylenequinone 3 10 pq this finding was consistent with results from elemental analysis oxygen carbon because a remarkable amount of dhpq originating from c geophilum also exists in the humic acids of soils and because the inputs of compounds to the lake depend strongly on the rivers perylene in the lake biwa sediment originates mainly from the dhpq of c geophilum in its catchment area

a possible terrigenous origin for perylene based on a sedimentary record of a pond lorraine france abstract the origin of perylene a five ring polycyclic aromatic hydrocarbon pah in sediments has been a matter of constant debate and its formation mechanisms remain unclear a perylene record in sediment was described and could support a clear link between perylene and terrigenous organic matter om input the distributions of pahs the variations of organic proxies such as the ratio of terrigenous to aquatic n alkanes tar hc and 5 h stanols 5 sterols ratio in sediments have been investigated sediments were sampled from a pond artificially created during the middle ages from a swampy area in the period prior to the pond creation for which high contributions of terrigenous om were evidenced perylene was found to be the predominant pah furthermore perylene content was shown to increase in response to the establishment of more reducing conditions this result supports the common idea that the main source of perylene is natural and derives from biogenic precursors under reducing conditions the creation of the pond in this wetland is marked by the deposition of a wood rich level characterized both by more oxygenated conditions and higher concentrations of perylene these high concentrations could result from the introduction of high concentrations of biogenic precursors of perylene under oxidative conditions subsequently the progressive burial of the woody level could have allowed the establishment of oxygen depleted conditions and the formation of perylene these results validate the use of perylene as a paleoenvironmental marker of terrigenous sources but it must be carefully used as a marker for syn or post depositional oxygen depleted conditions in lacustrine environments

mineralogy petrography and organic geochemistry of miocene coal seams in the kinik coalfield soma basin western turkey insights into depositional environment and palaeovegetation abstract the kinik coalfield is located in the south westernmost part of the soma basin in western turkey and hosts all three miocene coal seams from bottom to top km2 km3 and kp1 this study presents the coal petrographical mineralogical and organic geochemical features of samples collected from two deep cores samples from seam km2 generally display low ash yields and high toc content whereas the km3 and kp1 seams are characterized by relatively high ash yields and low toc values furthermore total s content of the kp1 is very high up to 7 0 on dry basis the maceral composition the coal facies diagrams and the distributions of n alkanes and diterpenoids indicate changes of depositional conditions and vegetation in the palaeomires of the km2 seam during early miocene the precursor peat of km2 seam started accumulating under limnotelmatic conditions followed by pure telmatic ones consequently initial mixed vegetation was replaced by a conifer dominant assemblage in the palaeomires in the upper parts of the km2 seam the coal facies indices and high concentrations of n alkanes along with the relatively low di di tri terpenoid ratios are indicators of the higher contribution of herbaceous species and minor abundance of conifers in the palaeomires of km3 and kp1 seams nevertheless the mineralogical composition of the km3 and kp1 seams indicate increased clastic input and alkalinity in the palaeomires that could reduce preservation of organic matter thus high ash yields and low toc were obtained from these seams in addition sulphate rich water supply along with synchronous pyroclastic air borne input into the palaeomires caused elevated total s content of the kp1 seam

from water to tillage erosion dominated landform evolution while water and wind erosion are still considered to be the dominant soil erosion processes on agricultural land there is growing recognition that tillage erosion plays an important role in the redistribution of soil on agricultural land in this study we examined soil redistribution rates and patterns for an agricultural field in the belgian loess belt 137cs derived soil erosion rates have been confronted with historical patterns of soil erosion based on soil profile truncation this allowed an assessment of historical and contemporary landform evolution on agricultural land and its interpretation in relation to the dominant geomorphic process the results clearly show that an important shift in the relative contribution of tillage and water erosion to total soil redistribution on agricultural land has occurred during recent decades historical soil redistribution is dominated by high losses on steep midslope positions and concavities as a result of water erosion leading to landscape incision and steepening of the topography in contrast contemporary soil redistribution is dominated by high losses on convex upperslopes and infilling of slope and valley concavities as a result of tillage resulting in topographic flattening this shift must be attributed to the increased mechanization of agriculture during recent decades this study shows that the typical topographical dependency of soil redistribution processes and their spatial interactions must be accounted for when assessing landform and soil profile evolution

perylene degradation during gradual onset of organic matter maturation abstract perylene and benzo a pyrene concentration changes during the gradual increase of thermal maturity have been analyzed for the palaeogene podhale flysh deposits and other palaeozoic to cenozoic sedimentary rock samples perylene is present in high relative concentration in the samples of maturation below 0 6 of the vitrinite reflectance rr while in the range of 0 6 0 7 rr its abundance rapidly decreased in the case of samples with vitrinite reflectance higher than 0 7 rr perylene compound disappeared completely benzo a pyrene is also thermally unstable at elevated temperatures and its relative concentration is very low above vitrinite reflectance values of ca 0 9 such results could have important palaeoenvironmental implications if these five ring polycyclic aromatic hydrocarbon compounds are characterized by low to moderate thermal stability then their use as a wood degrading fungi tracer in the case of perylene and palaeo wildfire indicator in the case of benzo a pyrene is limited only to samples of maturation below the oil window range and below the major phase of oil generation respectively these results explain the scarcity of perylene in palaeozoic sedimentary rocks which are generally of higher maturation than the younger deposits

a 200 year sedimentary record of progressive eutrophication in lake greifen switzerland implications for the origin of organic carbon rich sediments over the past 200 years lake greifen a small lake in northeastern switzerland has undergone dramatic changes in primary productivity and eutrophication due to increased nutrient supply from agricultural activity and industrialization a 40 year historical record of the water column chemistry indicates that productivity and eutrophication reached a maximum in 1974 after which stricter regulations on the input of nutrients resulted in a progressive decrease collected cores show the sedimentary expression of this anthropogenically induced eutrophication by a well developed annual sedimentation and by enhanced values of total organic carbon organic carbon accumulation rates and hydrogen indices hi of the kerogens analyses of the carbon isotopic composition of sedimentary carbonates and organic matter reveal that the fractionation between these two phases varies with the hi of kerogens this observation is explicable in terms of changing productivity and preservation of the organic matter and the co2 aq budget of the water body we propose that if high primary productivity were primarily responsible for the preservation and accumulation of organic matter then a negative correlation will occur between 13ccalcite organic matter 13ccal om and hi values in an environment with relatively low to moderate productivity but with bottom water anoxia a positive correlation will exist between 13ccal om and hi values this study of lake greifen has implications for understanding paleoenvironmental controls on ancient organic carbon rich sediments

oceanography of the eastern bering sea ice edge zone in spring1 the ice edge region of the southeast bering sea was studied in terms of the hydrographic regime phytoplankton biomass and primary productivity during the springs of 1975 through 1977 the results showed that a phytoplankton bloom occurs at the ice edge just as the spring ice decay period begins and that this accounts for a significant proportion of the annual carbon input over the shallow shelf the bloom is intensified in time and space by the influence of the ice edge on the physical structure of the water column specifically melting ice seems to increase the stability of the water column near and under the ice by lowering the salinity frontal structure in salinity and temperature are apparent at the ice edge and are attributed to the melting ice but also at times to wind driven ekman type upwelling these data are also related to recent short term ca months year climatic fluctuations that seem to control the seasonal position of the ice edge zone relative to the shelf break in cold years the ice edge comes southward to the shelf break and overlies the more nutrientrich alaska stream bering sea source water in warm years the ice edge zone does not reach this nutrient rich water this may be important to the biology of the ice edge ecosystem the edge zones of seasonal sea ice are biologically productive serving as focal points for the congregation of large numbers of marine birds and mammals and thus represent ecologically critical habitats in subpolar regions the presence of a cold and solid boundary influences the biological regime in several ways including effects on the physical and chemical regimes in the adjacent seawater at least three structural features of the water column often associated with high oceanic primary production can occur in such an area simultaneously water column stability frontal structures and under certain conditions ice edge upwelling we show here that there is enhanced primary production due to water column stability and frontal structure at the edge of the seasonal sea ice in spring our data also suggest that ice edge upwelling occurs we show further that the intense

distributions of polycyclic aromatic hydrocarbons in a sediment core from the north basin of lake biwa japan abstract we analyzed the vertical distributions of 19 polycyclic aromatic hydrocarbons pahs total organic carbon toc total nitrogen tn and stable carbon isotope ratio 13 c in a 27 cm sediment core from the north basin of lake biwa in order to elucidate changes in pah sources and events possibly affecting the lake over the last few decades both toc and tn increased gradually from the deepest layer toc 1 2 wt tn 0 14 wt to the uppermost layer toc 4 0 wt tn 0 45 wt the toc tn ratio a useful indicator for distinguishing between aquatic and terrestrial plant sources increased remarkably at 11 13 cm 10 3 11 1 vs 8 5 9 7 at other depths indicating that large amounts of terrestrial material entered the lake when that layer was deposited all pahs except perylene gradually increased from the deepest layer but not as clearly as toc and tn at 11 13 cm all pahs except perylene transiently decreased and perylene transiently increased since the pah ratios used for the elucidation of sources did not change greatly throughout the core we consider that the major source of pahs in the lake has not changed during the last few decades the brief decrease in pahs at 11 13 cm could be the result of dilution by a large input of terrestrial material which brought in perylene

new insights into the origin of perylene in geological samples abstract the origin of the polycyclic aromatic hydrocarbon pah perylene in sediments and petroleum has been a matter of continued debate reported to occur in phanerozoic organic matter om fossil crinoids and tropical termite mounds its mechanism of formation remains unclear while a combustion source can be excluded structural similarities to perylene quinone like components present in e g fungi plants crinoids and insects potentially suggest a product precursor relationship here we report perylene concentrations 13c 12c and d h ratios from a holocene sediment profile from the qingpu trench yangtze delta region china perylene concentrations differ from those of pyrogenic pahs and rise to prominence in a stratigraphic interval that was dominated by woody vegetation as determined by palynology including fungal spores in this zone perylene concentrations exhibit an inverse relationship to the lignin marker guaiacol d h ratios between 284 and 317 similar to the methoxy groups in lignin as well as co variation with spores from wood degrading fungi 13c 12c of perylene differs from that of land plant wax alkanes and falls in the fractionation range expected for saprophytic fungi that utilise lignin which is isotopically lighter than cellulose and whole wood during progressive lignin degradation the relative carbon isotopic ratio of the perylene decreases we therefore hypothesise a relationship of perylene to the activity of wood degrading fungi to support our hypothesis we analysed a wide range of phanerozoic sediments and oils and found perylene to generally be present in subordinate amounts before the evolutionary rise of vascular plants and to be generally absent from marine sourced oils few exceptions being attributed perhaps to a contribution of marine and or terrestrial derived fungi anoxia especially under marine conditions and or contamination of core material by fungi a series of low molecular weight aromatic quinones bearing the perylene backbone were detected in devonian and cretaceous sediments potentially representing precursor components to perylene

a simple and convenient determination of perylene preserved in the late neogene wood from northeastern tennessee using fluorescence spectroscopy abstract a new and convenient fluorescence spectroscopic method has been developed for the separation and determination of perylene in fossil wood recovered from a late miocene to early pliocene gray fossil site in tennessee usa this is the first report where perylene was separated from fossil samples from this newly discovered fossil site the chemical structure of perylene was elucidated and confirmed by uv visible and 1h nmr spectroscopies and esi tof high accuracy mass spectrometry the fluorescence of perylene was used to measure the contents of perylene in the fossil conifer and oak wood which were found to be 5 34 and 0 78 g g respectively the results suggested that the amount of perylene in the fossil conifer wood was 7 fold higher than that in the oak wood the method which uses highly sensitive fluorescence spectroscopy should provide a new approach for the analysis of other fossil and geochemical samples containing perylene

changes in the trophic state of lake erie discordance between molecular δ13c and bulk δ13c sedimentary records abstract prior to 1980 anthropogenic phosporus p loadings resulted in increased algal productivity and the deterioration of water quality within lake erie we measured c and n elemental compositions geolipid concentrations and 13 c values for bulk organic material and individual alkanes in samples taken from a 40 cm sediment core from the eastern basin of lake erie to infer recent trends in primary productivity and diagenesis the predominance of autochthonous algal derived c throughout the core is evidenced by low c n values 9 10 and the persistent abundance of n c 15 to n c 17 alkanes throughout the core the 13 c values of bulk organic c from lake erie vary between 25 9 and 24 9 with a maximum corresponding to the period of elevated historical p loading within lake erie 13 c values of short chained algal derived alkanes n c 18 are lower approximately 1 0 than their terrestrial derived homologs n c 25 down core variations in the 13 c composition of algal derived short chained alkanes do not exhibit the same trend as that observed for bulk organic c down core variation in 13 c values of individual alkanes likely reflect multiple diagenetic effects including kinetic fractionation effects variations in the relative contributions of isotopically unique n alkanes to the sediments and or temporal changes in 13 c enrichments of n alkanes associated with a single source high sedimentation rates characteristic of this core emphasize temporal variations in molecular 13 c values that might not otherwise be observed whereas 13 c data for bulk sedimentary organic c appear to reflect variation in trophic state the isotopic record for algal derived n alkanes e g n c 17 and pristane from lake erie must be considered from the perspective of molecular transformations

chemical evidence of differential particle dispersal in the southern washington coastal environment aliphatic hydrocarbons cupric oxide oxidation products of lignin and polycyclic aromatic hydrocarbons pah were analyzed by capillary gas chromatography in sediments from the southern washington continental shelf and slope the concentration of diploptene relative to plantwax n alkanes increased systematically in surface sediments with distance offshore along east west transects of the study area and remained constant in surface sediments along the midshelf silt deposit analogous trends were also observed for the concentration of cinnamyl phenols relative to vanillyl phenols and total methylphenanthrenes relative to phenanthrene these changes in sedimentary composition are evidence that diploptene from some terrestrial source lignin characteristic of non woody vascular plant tissue and a fossil organic material contained within weathered rock debris disperse across the washington continental shelf and slope in geographic patterns distinct from that for other river derived chemically related materials the compositional variations are explained by the particulate associations of the land derived chemicals and differential hydraulic dispersion of their respective carrier particles after discharge at the mouth of the columbia river

mass balance of the prince of wales icefield ellesmere island nunavut canada 1 this paper estimates the mass balance of the prince of wales icefield ellesmere island canada averaged over four decades from measurements of surface mass balance smb and iceberg calving shallow ice core net accumulation measurements and annual mass balance stake measurements are used in conjunction with a digital elevation model and knowledge of the location of the dominant moisture source for precipitation over the ice cap to interpolate and extrapolate spatial patterns of smb across the prince of wales icefield the contribution of iceberg calving to the mass balance is calculated from estimates of 1 the annual volume of ice discharged at the major tidewater glacier termini and 2 the annual volume loss or gain due to terminus fluctuations two different approaches to determining the smb conclude that the smb of the ice field is approximately in balance average equals 0 1 0 4 km3 w e a 1 where w e means water equivalent largely because of its proximity to the main year round moisture source that is the smith sound portion of the north open water polynya iceberg calving is a highly significant component of mass loss 1 9 0 2 km3 w e a 1 and is sufficient to make the overall mass balance of the ice field averaged over the period 1963 2003 clearly negative 2 0 45 km3 w e a 1 equivalent to a mean specific mass balance across the ice field of 0 1 m w e a 1 the prince of wales icefield contributes 0 005 mm a 1 to global eustatic sea level rise

perylene an indicator of alteration processes or precursor materials abstract perylene is a polycyclic aromatic hydrocarbon pah that is found pervasively in both marine and freshwater sediments yet its origin remains obscure we have explored relationships between perylene and possible precursor materials in two 210 pb dated sediment cores from lake ontario in which contributions of aquatic and land plant organic matter and concentrations of anthropogenic pahs have been measured no significant correlations were identified between perylene occurrence and indicators of terrigenous or aquatic sources of organic matter distinct differences between perylene and anthropogenic pah sedimentary profiles rule out an industrial source for perylene at these locations the general pattern of low to absent perylene concentrations in upper oxic sediments and increasing concentrations with depth indicates that in situ diagenesis under anoxic conditions produces perylene and that its formation is kinetically controlled the results of our study suggest that perylene is formed from non specific precursor materials by biotic or abiotic transformation processes if this scenario accurately describes its formation then perylene is an indicator of depositional conditions rather than the source of organic matter

biomarker and stable carbon isotope systematics of fossil wood from the second lusatian lignite seam of the lubstow deposit poland abstract decay of fossil wood gelification collected from the middle miocene 2nd lusatian lignite seam at the lubstow open cast mine poland is characterised by its maceral variety fluorescence intensity and cellulose content cellulose decomposition leads to lower molar h c ratio values of the organic matter as indicated by higher total organic carbon toc content of samples characterised by low cellulose content biochemical formation of hydrocarbons in the wood due to enhanced microbial activity is evidenced by higher hydrocarbon content in the extracts higher relative proportions of n alkanes and hopanoids are observed in the hydrocarbon fractions of wood remains characterised by low cellulose yield the results provide evidence for the formation of these compounds during biogeochemical transformation of organic matter hopanoid contents are considered to reflect the activity of aerobic bacteria and or fungi because of enhanced perylene content in the hydrocarbon fractions from gelified wood samples fungi are considered as the major precursor carriers of this polycyclic aromatic hydrocarbon the results provide evidence that biomarker composition of fossil wood can be used to trace biochemical transformation processes chemotaxonomical classification of fossil wood fragments as gymnosperms most probably species of the coniferales families taxodiaceae cupressaceae are based on the molecular composition of terpenoid hydrocarbons and a mean 13 c value of 24 5 depletion of gelified samples in 13 c as compared to ungelified wood is caused by the effect of progressive decomposition of cellulose the data indicate that cellulose 13 c data mean 13 c 20 8 are also affected by wood decomposition and so only samples with comparable cellulose content should be used for the reconstruction of environmental changes inter species as well as intra plant variation in carbon isotope differences and of decay resistance between cellulose and lignin have to be taken into account

preservation of elemental and isotopic source identification of sedimentary organic matter the amount and type of organic matter in the sediments of lakes and oceans contribute to their paleoenvironmental and paleoclimatological records only a small fraction of the initial aquatic organic matter survives destruction and alteration during sinking and sedimentation selective degradation modifies the character of the surviving small fraction of organic matter which becomes incorporated in bottom sediments organic matter alterations can continue to sub bottom depths of hundreds of meters corresponding to millions of years source and paleoenvironmental information nonetheless remains preserved in the molecular elemental and isotopic compositions of organic matter c n and 13c values of total organic matter in particular appear to retain paleoenvironmental information for multi myr time periods

oceanographic conditions in the marginal ice zone north of svalbard in early fall 1979 with an emphasis on mesoscale processes during september october 1979 the norwegian remote sensing experiment was carried out in the marginal ice zone north of svalbard convergence of the ice cover is correlated with along ice edge winds with the ice to the right while divergence occurs during office winds or calm conditions a wind driven ice edge jet is observed wind driven upwelling of the pycnocline of up to 7 m was present along the ice edge during a 10 to 15 m s easterly wind event the upwelling is due to ekman divergence at the ice edge caused by higher wind stress over ice than over open water the ice edge meanders with a scale of 20 40 km and sheds eddies with a scale of 5 to 15 km into the open water this scale is of the same order as the rossby radius of deformation eddies with the same scale are also seen in the conductivity temperature and depth observations conditions during the experiment were such that barotropic instabilities could have generated these eddies

perylene dominance in sediments from a subtropical high mountain lake perylene formation in sediments of water bodies has been a topic of continual discussion and debate we report the concentration and age ca 660 yr profiles of perylene and other polycyclic aromatic hydrocarbons pahs in a sediment core from emerald peak lake the largest high mountain lake in taiwan perylene is dominant at all depths of the sediment ranging from 60 to 98 of total pahs a feature not commonly found in other sediments the concentration profile of perylene with sediment age fits a first order kinetic model which might be an indication of a steady sedimentary environment

marine aerosol source regions to prince of wales icefield ellesmere island and influence from the tropical pacific 1979 2001 using a coastal ice core collected from prince of wales pow icefield on ellesmere island we investigate source regions of sea ice modulated chemical species methanesulfonic acid msa and chloride cl to pow icefield and the influence of large scale atmospheric variability on the transport of these marine aerosols 1979 2001 our key findings are 1 msa in the pow icefield core is derived primarily from productivity in the sea ice zone of baffin bay and the labrador sea with influence from waters within the north water now polynya 2 sea ice formation processes within the now polynya may be a significant source of sea salt aerosols to the pow core site in addition to offshore open water source regions primarily in hudson bay and 3 the tropical pacific influences the source and transport of marine aerosols to pow icefield through its remote control on regional winds and sea ice variability regression analyses during times of msa deposition reveal sea level pressure slp anomalies favorable for opening of the now polynya and subsequent oceanic dimethyl sulfide production regression analyses during times of cl deposition reveal slp anomalies that indicate a broader oceanic region of sea salt sources to the core site these results are supported by scanning multichannel microwave radiometer and special sensor microwave imager based sea ice reconstructions and air mass transport density analyses and suggest that the marine biogenic record may capture local polynya variability while sea salt transport to the site from larger offshore source regions in baffin bay is likely regression analyses show a link to tropical dynamics via an atmospheric rossby wave

coal related sources of organic contamination in sediments and water from the bierawka river poland abstract river sediments mixed with coaly material occur all along the length of the bierawka river poland to identify the origin of the coal in the sediment the coaly material was investigated by reflected light microscopy and rock eval pyrolysis and solvent extracts by gas chromatography mass spectrometry gc ms organic compounds dissolved in water were separated by solid phase extraction spe and analyzed by gc ms the results point to a kerogen iii source petrographic analyses confirm abundant coal charred and coked particles in the sediments vitrinite reflectance varied between 0 66 0 80 r r without any large spatial variation the coaly particles have different sources generally the primary origin of coal particles is from coal processing and the dumping the ash with unburned coal particles from a glass factory near the river source later this material was redeposited along the entire river course in addition hard coal processing crushing washing features are visible in larger coal pieces a second source of coaly organic matter is a coal waste dump at szczyglowice where intensive erosion of steep slopes has delivered copious amounts of organic matter into the river the mixing of this organic matter with that from the glass factory is clearly identified on a ternary diagram pah distributions also show differences between sections the coal particle input from the waste dump increased the relative content of naphthalene relative content downstream as in the coal waste 4 5 ring pahs predominate in the sediments the pyrogenic origin of pahs and aromatic compounds such as methylbiphenyls and dibenzofurane in the sediment is indicated by diagnostic pah ratios burned particles were identified petrographically the river water contains only 2 3 ring pahs possibly of industrial origin or leached from coal particles in the river sediments

biogeomorphological influence of the hawaiian silversword argyroxiphium sandwicense dc on soil erosion in haleakala maui hawai i abstract soils were examined at 2505 m elevation in haleakala s crater maui hawai i beneath 50 adult hawaiian silversword plants argyroxiphium sandwicense dc mean canopy diameter was 42 0 cm exposed volcanic inceptisols andic humitropepts seem significantly eroded beyond the dense rosette crowns but remain unaffected below plants rosettes are perched on isolated basal soil mounds or pedestals 27 121 mm high mean 77 5 mm geomorphic field response of soils below rosettes and adjacent 100 cm apart bare soils differs infiltration rates are higher under plants mean 158 7 mm min than in exposed control soils 60 0 mm min soils below silverswords also show greater shear strength 146 1 g cm 2 and compressibility 2 795 kg cm 2 than unprotected soils 36 1 g cm 2 and 0 108 kg cm 2 respectively soil in the plant mounds contains more organic matter this has influenced other pedological properties which also differ substantially between sampling positions substrate under plants has a porosity 53 higher than exposed soil while bulk density is 62 higher in soil outside the plant crown the observed microtopographic differences are ascribed to greater soil erosion by rainsplash and runoff outside the silversword canopy the dense rosette crown effectively intercepts raindrops soils beneath plants also have a high surface cohesiveness provided by a dense network of fine plant rootlets and partially decomposed organic material higher runoff rates occur on the less permeable substrate beyond rosettes which is affected by soil crusting

perylene as an indicator of conifer fossil wood degradation by wood degrading fungi the occurrence of perylene in middle jurassic fossil wood and miocene xylites from poland is described along with its correlation with unsubstituted polycyclic aromatic hydrocarbons pahs as well as cellulose content both middle jurassic and miocene wood remnants were of relatively low maturity ca 0 2 0 3 vitrinite reflectance rr had excellent preservation of biomarkers and biomolecules and in the case of the middle jurassic fossil wood samples generally good preservation of anatomical structures due to early diagenetic mineralisation the results from 42 middle jurassic and 8 miocene most taxonomically defined fossil wood fragments demonstrated a negative correlation between the concentration of perylene and those of generally typical conifer biomarkers e g cadalene dehydroabietane simonellite and retene in addition good correlation r2 0 81 was observed between the ratio of perylene to the above conifer biomarkers and the ratio of pahs phenanthrene and fluoranthene and pyrene to the conifer biomarkers this implies that the high concentration of perylene in fossil wood indicate its extensive degradation during decay transport and early diagenesis we defined a conifer wood degradation index as cwdi perylene perylene cadalene retene simonellite dehydroabietane cwdi perylene perylene cadalene retene simonellite dehydroabietane and observed a wide range of values 0 001 for less degraded wood to 0 95 for highly degraded samples anatomical wood preservation was associated with cwdi values in most of the samples characterised by poorly preserved anatomy high cwdi values were observed while anatomically well preserved samples generally had lower cwdi values we determined similar 13c values for perylene from the fossil wood samples 26 4 to 27 8 whereas the values for the conifer biomarkers were slightly higher and varied from 25 6 to 26 6 in contrast pyrene was depleted in 13c 27 5 to 28 2 the carbon isotope values of perylene are consistent with an origin from wood degrading fungi

sensitivity studies with a coupled ice ocean model of the marginal ice zone an analytical coupled ice ocean model is considered which is forced by a specified wind stress acting on the open ocean as well as the ice the analysis supports the conjecture that the upwelling dynamics at ice edges can be understood by means of a simple analytical model in similarity with coastal problems it is shown that the ice edge upwelling is determined by the net mass flux at the boundaries of the considered region the model is used to study the sensitivity of the upwelling dynamics in the marginal ice zone to variation in the controlling parameters these parameters consist of combinations of the drag coefficients used in the parameterization of the stresses on the three interfaces atmosphere ice atmosphere ocean and ice ocean the response is shown to be sensitive to variations in these parameters in that one set of parameters may give upwelling while a slightly different set of parameters may give downwelling

feedback between ice flow barotropic flow and baroclinic flow in the presence of bottom topography coupling between externally driven barotropic flow and locally driven baroclinic flow in the presence of an ice cover and topography is studied the topography is a necessary ingredient in this coupling this study shows that the observed mesoscale activity of the ice edge seen in satellite imagery does not necessarily reflect the mesoscale baroclinic activity in the ocean besides oceanic eddies the ice cover can trace the topographic changes via the coupling to the barotropic flow a two layer ocean model coupled to an ice model is constructed to simulate an ice ocean system with a varying bottom topography in the absence of wind forcing the ice cover reflects the externally driven barotropic ocean response especially topographically forced taylor columns by forming ice streamers or meanders some of these features propagate advected with the ocean currents as a whole downstream creating an image of eddy propagation even though there is no baroclinic structure underneath when downwelling favorable winds ice on the left from the wind direction are turned on in addition to this background barotropic flow the ekman flow in the ocean toward the open ocean will enhance the meandering of the ice edge due to the barotropic flow during upwelling favorable winds the ice edge stays rather compact including the case when a strong baroclinic cyclonic vortex is developing beneath an ice meander supported by the taylor column in the ocean

an investigation of a polynya in the canadian archipelago 1 introduction and oceanography in certain parts of the canadian archipelago small localized areas of water remain ice free throughout the winter despite the extreme temperature differences between the atmosphere and the ocean surface one such area close to dundas island has been studied in detail both from the point of view of the atmospheric oceanic heat exchange over the open water and its local geographic and oceanographic context this paper describes the oceanography of the area and local weather and tidal flow conditions a significant feature of the oceanographic records is a strong modulation of near surface ocean temperature at tidal frequencies involving temperature differences as great as 0 2 c within a single tidal cycle for the most part the surface waters are 0 1 to 0 2 c above freezing the presence of this relatively warm surface water is thought to be due to upward mixing occasioned by fast tidal flows across the shallow sill connecting dundas and devon islands historical records of water properties in the sverdrup basin lying to the north of the polynya area show temperatures substantially above freezing point at depths of 50 m and below this readily accessible body of warm water is thought to be the source of the sensible heat required for the existence of the polynya this is supported by existing current measurements which suggest a mean southerly transport in the channels leading into and out of the region of the polynya site a tentative application of the atmospheric heat flux measurements to the whole dundas island bailey hamilton island area suggests that sufficient heat may be lost to affect significantly the water column further south in crozier strait and wellington channel the limited information available shows the more southerly waters of these passages to be relatively well mixed and cooled relative to the water of the sverdrup basin just to the north of the dundas polynya area

oceanography of nares strait and northern baffin bay in 1986 with emphasis on deep and bottom water formation temperatures and salinities were measured from northern baffin bay through nares strait to the southern edge of the lincoln sea in september 1986 the water properties and baroclinic circulation in general did not vary widely from earlier measurements but close station spacing led to the recognition of the rapid rate of dilution of arctic intermediate water as it debouches into deeper water from the southern end of kane basin as a result this intermediate water becomes a much less likely source for the deep and bottom waters of baffin bay the formation of deep and bottom waters more likely is initiated by the formation of cold saline water in winter in the shallows of eastern smith sound under the thin ice of the north water this water then undergoes multicomponent mixing with the waters en route from its origin to the deep basin of baffin bay

annual accumulation at two sites in northwest greenland during recent centuries during summer 1995 150 m firn and ice cores were drilled to determine annual accumulation rates at two greenland sites 73 84 n 49 49 w nasa u site and 78 53 n 56 83 w humboldt glacier site annual layers were identified in the cores using multiple parameters 18 o and concentrations of dust h 2 o 2 nh 4 ca 2 and no 3 using all parameters together to define annual layers resulted in a 350 year record for the nasa u core with no dating uncertainty for the lower accumulation humboldt core the dating uncertainty is about 5 years over the 852 year period of record with no uncertainty over the past 200 years annual accumulation over the periods of record at the two sites averaged about 0 34 and 0 14 m water equivalent respectively a set of 20 m firn cores drilled near the main 150 m cores showed that interannual variability of accumulation exceeded spatial variability at nasa u the humboldt cores showed equal spatial and interannual variability the accumulation rates at both sites showed a low frequency variation of about 100 years and both sites showed 200 year cumulative fluctuations of about 2 m from mean accumulation rates compared to central greenland and to nasa u the humboldt core showed higher annual accumulation rates around 1760 1810 possibly indicating a changed circulation pattern for the more northern part of greenland in that period

early holocene palaeoceanography and deglacial chronology of disko bugt west greenland two new cores from disko bugt a large marine embayment in west greenland are used to assess the deglacial chronology and palaeoceanography of the area during the early holocene deglaciation of the main part of disko bugt is directly dated for the first time to a minimum of ca 10 2 ka cal bp by this time the jakobshavn isbrae ice stream had retreated to the eastern margins of disko bugt initial deglaciation took place before the relatively warm west greenland current wgc was initiated a strengthening in the wgc is identified from ca 9 2 ka cal bp accompanied by retreat of the ice stream to a shallow bank immediately west of the present day jakobshavn isfjord while in this position the calving and melting ice stream produced large volumes of sediment and meltwater the large volumes of meltwater prevented the relatively warm waters of the wgc reaching the eastern margins of disko bugt the ice stream remained grounded on this bank for over a thousand years until ca 7 9 ka cal bp when reduced sedimentation rates and an increase in boreal fauna point to its retreat inside the present day fjord system

spatial patterns and seasonal variation of snowpack sulphate isotopes of the prince of wales icefield ellesmere island canada ion chemistry and sulphate isotope values for snow samples from the prince of wales icefield ellesmere island canada show distinct seasonal trends and spatial patterns sixteen surface snow samples from two transects and 30 samples from five depth profiles representing fall 2003 to spring 2004 accumulation have been analyzed surface snow samples show decreasing so4 2 and na concentrations along with decreasing d 34 s values with distance inland and increased elevation these trends follow an expected pattern of decreasing sea salt aerosol impact with greater vertical and horizontal distance from sea water sources depth profile total sulphate and non sea salt sulphate increase in concentration with height in the snowpack and these results combined with d 34 s values that are more positive in fall snow are consistent with increased amounts of anthropogenic sulphate in surface spring snow sulphate apportionment was performed on surface snow assuming an isotopically light sulphate source anthropogenic plus volcanic mixed with isotopically heavier sulphate from dimethylsulphide dms oxidation and sea water isotopically light sulphate in surface snow was apparent at all elevations at a reasonably uniform concentration dms sulphate however decreased exponentially with altitude reflecting an ocean level source with oxidation occurring during transport and deposition the significance to multi year deposition studies is that sulphate from dms oxidation may be related to sea ice conditions in the region

composition and origin of organic matter in surface sediments of lake sarbsko a highly eutrophic and shallow coastal lake northern poland abstract we present an organic geochemical study of surface sediments of lake sarbsko a shallow coastal lake on the middle polish baltic coast the aim was to provide evidence concerning the origin of the organic matter om and its compositional diversity in surface deposits of this very productive highly dynamic water body the content and composition of the om in the bottom sediments were investigated at 11 sampling stations throughout the lake basin om sources were assigned on the basis of bulk indicators total organic carbon toc total nitrogen tn 13 c toc and 15 n and extractable om yield biomarker composition of extractable om and compound specific c isotope signatures the source characterization of autochthonous compounds was verified via phytoplankton analysis the distribution of gaseous hydrocarbons in the sediments as well as temporal changes in lake water ph the concentration of dic dissolved inorganic carbon and 13 c dic were used to trace om decomposition the sedimentary om is composed mainly of well preserved phytoplankton compounds and shows minor spatial variability in composition however the presence of ch 4 and co 2 in the bottom deposits provides evidence for microbial degradation of sedimentary om the transformation of organic compounds in surface bottom and pore waters via oxidative processes influences carbonate equilibrium in the lake and seasonally favours precipitation or dissolution of caco 3 the data enhance our understanding of the relationships between the composition of sedimentary om and environmental conditions within coastal ecosystems and shed light on the reliability of om proxies for environmental reconstruction of coastal lakes

the hybrid polynya at the northern end of nares strait noaa satellite images november through june 1984 to 1989 show sea ice arches accompanied by unique polynya patterns immediately north of the nares strait typically the arches formed by late november but the polynya patterns did not stabilize until january the month when sea ice transport through the strait usually ceases the polynyas created to the lee of the arches appear to be of an unusual hybrid mix switching from a combined latent and sensible heat type in fall to a pure sensible heat type in winter early in the polynya formation sea ice is removed through the temporarily open nares strait while the ice arch to the north blocks ice from drifting into the polynya once the strait freezes solid newly formed ice cannot be transported downstream the polynya then begins to freeze but ice growth is still moderated apparently due to upward vertical mixing of warmer more saline water generated by tidal currents flowing over the shallow seabed northwest of robeson channel

insights into the origin of perylene from isotopic analyses of sediments from saanich inlet british columbia perylene is an abundant and common polycyclic aromatic hydrocarbon in sedimentary settings yet its origin remains puzzling we have investigated the relation of perylene to the amount and type of organic matter in the sediments of saanich inlet a coastal marine anoxic basin organic matter is predominantly marine in origin but the proportions of marine and land derived components have varied perylene concentrations generally increase with sediment depth relative to toc which indicates continued formation of this compound by microbially mediated diagenesis perylene 13c values range between 27 7 and 23 6 whereas toc 13c values vary narrowly from 21 7 to 21 2 over the same sediment depth interval the variation in isotopic difference suggests that perylene originates from more than one precursor material both aquatic and continental organic matter different microbial processes or some combination of these possibilities

an overview of physical processes in the north water the presence of a polynya strongly affects biological processes by influencing underwater light levels water column stratification the upwelling of nutrients and the timing of production cycles an overview of the existing literature on the oceanography meteorology and sea ice conditions of the north water a large recurring polynya in northern baffin bay is presented the north water is influenced by a cold inflow of arctic ocean water from the north and in some areas a warmer inflow of atlantic water from the south earlier observations and modeling studies suggested that both wind and ocean advection of sea ice as well as heat input to the surface waters by either upwelling or mixing were responsible for the formation and maintenance of the polynya recent data indicate the north water to be primarily generated by the southward drift of ice by winds and currents as opposed to melting ice by sensible heat input over large areas localized sensible heat effects occur in fall winter and spring along the greenland side of the polynya

lipids of aquatic organisms as potential contributors to lacustrine sediments ii abstract the relationship between the lipid composition of organisms in the water column of an eutrophic lake and the lipid composition of underlying sediments previously examined for n alkanols and steroids is now reported for hydrocarbons ketones and carboxylic acids the n c7 alkane and alkenoic acids from two primary sources are rapidly metabolized in the water column and surficial sediment bacterial biomarkers including hopenes and i ai branched fatty acids were detected in the photosynthetic bacterial layer occurring just above the sediment water interface within the sediment the apparent conversion of free n alkanes alkan 2 ones and hydroxy acids to the corresponding bound form is noted microbiological oxidation of n alkanes to alkan 2 ones is supported by the detection of the intermediate alkan 2 ols with a distribution similar to that of the ketones the geochemistry of sediment deposited c 1900 prior to biological study of the site was interpreted from stable biomarkers and the diagenetic changes recognised in the study of contemporary deposition a qualitative difference in algal input to the older sediment is inferred from the low 7 sterol content and presence of 2 6 10 trimethyl 7 3 methylbutyl dodecane however there was still significant dinoflagellate input as indicated by the presence of 4 methylsterols a difference in higher plant input to the older sediment indicated from the n alkane alkene and triterpenoid ketone distributions is consistent with the recent development of tree cover

improved mapping of sea ice production in the arctic ocean using amsr e thin ice thickness algorithm new and improved estimates of sea ice production in the arctic ocean are derived from amsr e satellite and atmospheric reanalysis data for the period 2002 2011 at a spatial resolution of 6 25 km and using a newly developed fast ice mask high ice production in the major coastal polynyas is well demonstrated the total annual cumulative ice production in the major 10 polynya regions is about 1180 70km 3 the interannual variability of the ice production for each polynya is presented during 2002 2011 no obvious relationship is noted between the ice production and the recent drastic reduction in the preceding summer arctic sea ice extent most polynya regions exhibit maximum ice production in autumn october november before areas offshore have been covered with consolidated pack ice sea ice production from october to november in the marginal ice zone of the pacific ocean sector is negatively correlated with summer ice extent there the ice production from october to november of 2007 a record minimum summer ice extent was about twice as large as that in other years the high ice production area shifted to higher latitudes i e toward the deep canada basin due to the retreat of the summer ice edge we speculate that the resultant increase in brine input could change the oceanic structure in the basin specifically deepening the winter mixed layer 2014 american geophysical union all rights reserved

mound measurements quantifying medium term soil erosion under olive trees in northern jordan abstract over the last few decades many quantitative erosion studies have revealed that olive orchard expansion and increased mechanization in southern european countries have led to increased soil erosion under olive trees consequently these studies have suggested different methods of mitigation in light of the 2014 european trading zone expansion to countries east and south of the mediterranean a further intensification of olive plantations is postulated to meet market demands to attain first medium term estimates of erosion in northern jordan and its driving factors a new method measuring olive mounds was implemented seven fields with clearly erosive structures were chosen throughout the wadi al arab catchment in northern jordan topographic measurements were used to reconstruct the historical and recent surface level and calculate the volume eroded since the planting of the trees a total of 81 bulk density measurements and 14 tree cores allowed the estimation of the soil loss in tons per hectare the combination of modified land use map and slope information helped to identify similar olive fields with high erosive potential results show that the method provides medium term quantitative estimates for averaged soil loss consistent with some existing results from similar research areas in the mediterranean they clearly indicate the significant potential for erosion in olive orchards with around 95 8 t ha 1 yr 1 tillage practice and water erosion were identified as critical erosion processes both depending on tillage characteristics tillage timing and soil parent material the investigated fields represent about 19 of the catchment s surface area and are likely to contribute to the measured yearly sediment yield that fills up the wadi al arab reservoir with sediments

a coupled ice ocean model of upwelling in the marginal ice zone a dynamical coupled ice ocean numerical model for the marginal ice zone miz is suggested and used to study upwelling dynamics in the miz the nonlinear sea ice model has a variable ice concentration and includes internal ice stress the model is forced by stresses on the air ocean and air ice surfaces the main coupling between the ice and the ocean is in the form of an interfacial stress on the ice ocean interface the ocean model is a linear reduced gravity model the wind stress exerted by the atmosphere on the ocean is proportional to the fraction of open water while the interfacial stress ice ocean is proportional to the concentration of ice a new mechanism for ice edge upwelling is suggested based on a geostrophic equilibrium solution for the sea ice medium the upwelling reported in previous models invoking a stationary ice cover is shown to be replaced by a weak downwelling due to the ice motion most of the upwelling dynamics can be understood by analysis of the divergence of the across ice edge upper ocean transport on the basis of numerical model an analytical model is suggested that reproduces most of the upwelling dynamics of the more complex numerical model

warm water cells in the north water northern baffin bay during winter sea surface temperatures above the freezing point of seawater 1 8 c were observed in the north water during winter and early spring the result indicates a possibility of upwelling warm water presumably of atlantic origin brought from lower depths to the surface the warm water temperatures ranged from 1 7 to 0 1 c the highest occurrence frequency lay in the temperature interval from 1 0 to 0 8 c most warm water cells were found along the greenland coast in smith sound lady ann strait and barrow strait they occurred most frequently in smith sound west of cape alexander the highest temperatures of 0 1 c occurred however south of cape alexander the occurrence frequency and the total area of warm water patches decreased toward spring the predominantly northerly wind that is channeled in smith sound accounts for a mean ice drift of approximately 17 km d 1 this ice drift causes an ice divergence in smith sound and along the greenland coast the existence of warm water areas can be explained by the strong northerly wind resulting in a coriolis force that induces coastal upwelling the wind induced offshore transport of 3 5 105 m3 s 1 in the north water compensated by the upwelling of atlantic baffin bay water 0 c along the greenland coast will suffice to keep 10 of the north water ice free the combination of ice divergence and forced convection of warm water can be considered as a prime cause of the polynyas in the north water

perylene occurrence alkylation and possible sources in deep ocean sediments abstract 81 deep ocean sediment samples obtained from the dsdp ipod program legs 63 66 and six gravity cores from dsdp ipod leg 64 guaymas basin gulf of california site survey cruise sio were analyzed for perylene s perylene was found to be most abundant in anoxic diatomaceous sediments containing moderate amounts of silts and or clays elevated perylene yields normalized to organic carbon contents coincided with enhanced preservation of autochthonous tetraterpenoid and tetrapyrrole pigments indicating a requirement of anoxia in the formation of perylene strongly euxinic conditions correlate with decreased perylene yields but not its total absence as found for strongly aerobic deposition and or redeposition perylene alkylation occurs in response to increasing in situ temperatures alt sub bottom depth this alkylation was found to begin with the generation of methyl c 1 perylene and to eventually yield a perylene alkyl perylene homologous series in decreasing abundance through the equivalent of c 3 trimethyl methyl ethyl propyl perylene the realm of most intense perylene alkylation for quaternary or pliocene miocene sediments corresponds with present in situ temperatures of 40 50 c or 30 35 c respectively thus the degree of perylene alkylation may represent an organic indicator for the thermal history of immature sediments geological phenomena such as reworking and igneous intrusions were found to complicate downhole perylene alkylation patterns a substituted c4h7o2 perylene was isolated from several anoxically deposited diatomaceous oozes and may represent one of the many possible perylene precursors the possible source compounds and biota for sedimentary perylene are discussed in light of the present study and review of past reports

production sedimentation and isotopic composition of organic matter in lake ontario organic matter and its carbon and nitrogen isotopic composition were measured in sequential sediment trap and core samples from the rochester basin of lake ontario to evaluate their usefulness in reconstructing historic changes in lake productivity the greatest flux of organic matter from the epilimnion occurred during late summer and coincided with whiting events indicating that calcite precipitation is an effective mechanism for sedimenting organic matter carbon isotopes of organic matter were low prior to the onset of stratification increased to maximum values in late summer and then decreased following fall overturn this pattern is controlled mainly by the timing of stratification and primary productivity which preferentially removes 12co2 from the epilimnion the physiological effect of decreased carbon isotopic fractionation with decreasing supplies of co2 aq may have also contributed to increased 13corgc nitrogen isotopes showed a seasonal pattern opposite to that of carbon whereby 15n values were low during the summer stratified period and high for the remainder of the year seasonal variability in 15norgn probably reflects changes in the source of sedimented organic particles which is dominated by isotopically depleted phytodetritus during the stratified period and isotopically enriched organic matter from heterotrophic or detrital sources during the mixed period a comparison of organic carbon accumulation rates and 13corgc between sediment cores collected in 1987 and 1993 1994 confirms earlier predictions that diagenetic processes reduce the mass accumulation of organic carbon in the zone of oxic pore waters but will not change the 13corgc values all cores analyzed for 13corgc display the reproducible pattern of a progressive increase in the 19oos peaking in the early to mid 1970s and then decreasing to the present this pattern matches the historical trends of phosphorus loading to the basin suggesting that 13c of organic carbon is a reliable proxy for paleoproductivity and responds to spring phosphorus supplies in the water column the 15n of sedimentary organic matter increased linearly from 1840 to 1960 at a rate of 0 3ppt per decade and remained relatively constant thereafter except for an increase in the upper few centimeters of sediment the increase in 15norgn reflects a combination of factors including early forest clearance by europeans increased sewering by municipalities after 1940 and increased nitrate utilization as productivity increased in the lower great lakes increased rates of denitrification in the central basin of upstream lake erie from the 1930s to the early 1970s may have also contributed to the rise in 15norgn values

origin distribution and environmental significance of perylene in okinawa trough since last glaciation maximum perylene a five ring nuclear polycyclic aromatic hydrocarbon pah has a different distribution pattern from anthropogenic pahs its source however remains obscure limiting its application as an environ mental indicator here we examine perylene in the upper 85 m sediments of the odp hole 1202b from the southern okinawa trough over the past 20 000 years the mass accumulation rate of perylene is sub stantially higher in the last deglaciation than the holocene and last glacial maximum perylene presents a strong correlation with c31 n alkane r 0 55 p 0 001 a biomarker for terrigenous organic matter and a weak correlation with c37 2 alkenone r 0 04 p 0 23 a biomarker for marine organic matter the mean d 13 c value of perylene 22 8 0 6 is substantially higher than that of long chain n alkanes 30 7 0 4 but close to that of fluvial organic matter in adjacent areas 24 0 to 25 0 our results strongly suggest that the perylene is of a terrigenous origin likely from soil fungi and may be a useful tracer for soil organic carbon in marine environments

applying a simple methodology to assess historical soil erosion in olive orchards abstract although soil erosion is a well known problem in olive orchards causing both on site soil degradation and off site environmental pollution quantitative field measurements of soil erosion are scarce this situation has restrained the development of a reliable predictive soil erosion model for this land use this study applies a simple and inexpensive technique to measure soil losses in olive orchards over a medium term time scale the methodology is based on measuring the size of small mounds that form around individual trees the resulting historical soil loss rate averaged for seven sites and over a period between 55 100 years was 95 mg ha 1 yr 1 locally the historical soil loss rate amounted up to 184 mg ha 1 yr 1 the measurement of actual erosion by water yielded a soil loss rate between 70 100 mg ha 1 yr 1 this difference illustrates the important contribution of tillage translocation our approach provides novel insights into the intensity and processes of soil erosion in olive orchards it also provides valuable input for model calibration and validation

the circulation water masses and sea ice of baffin bay abstract the oceanographic meteorological and sea ice conditions in baffin bay are studied using historical hydrographic satellite and meteorological data and a set of current meter data from a mooring program of the bedford institute of oceanography baffin bay is partially covered by sea ice all year except august and september the interannual variation of the ice extent is shown to be correlated with winter air temperature available hydrographic data were used to study the water masses and the horizontal and vertical distribution of temperature salinity three water masses can be identified arctic water in the upper 100 300 m of all regions except the southeast west greenland intermediate water at 300 800 m in most of the interior of baffin bay and deep baffin bay water in all regions below 1200 m the temperature and salinity in baffin bay have limited seasonal variability except in the upper 300 m of eastern davis strait northern baffin bay and the mouth of lancaster sound summer data have a temperature minimum at 100 m which suggests winter convection does not penetrate deeper than this depth current meter data and results of a circulation model indicate that the mean circulation is cyclonic the seasonal variation of the currents is complex overall summer and fall tend to have stronger currents than winter and spring at all depths among the different regions the largest seasonal variation occurs at the mouth of lancaster sound and the baffin island slope model generated velocity fields show a basic agreement with the observed currents and indicate strong topographic control in the vicinity of davis strait and on the greenland shelves the model also produces a southward counter current on the greenland slope which may explain the observed high horizontal shears over the greenland slope estimates of the volume and fresh water transports through lancaster jones and smith sounds are reviewed transports through davis strait are computed from the current meter data the balance of freshwater budget and sensitivity of the thermohaline circulation to freshwater transport are discussed

facies evolution and stratigraphic correlation in the early oligocene tard clay of hungary as revealed by maceral biomarker and stable isotope composition abstract hydrocarbon source rocks i e tard clay formation containing type ii organic matter were deposited in the hungarian paleogene basin during lower oligocene a major contribution of aquatic organisms green algae dinoflagellates chrysophyte algae and minor inputs from macrophytes and land plants to organic matter accumulation is indicated by n alkane distribution patterns composition of steroids and 13c of hydrocarbon biomarkers microbial communities included heterotrophic bacteria cyanobacteria chemoautotrophic bacteria as well as green sulphur bacteria the presence of methanotrophic bacteria is indicated by 13c depleted hop 17 21 ene higher inputs of terrestrial organic matter occurred during deposition of the lower and uppermost units of the tard clay formation the terpenoid hydrocarbon composition argues for angiosperm dominated vegetation in the area of the hungarian paleogene basin diterpenoid hydrocarbons derived from the resins of conifers are about 2 3 enriched in 13c compared to the angiosperm biomarkers environmental conditions changed from marine to brackish accompanied by oxygen depletion in the lower parts of the water column organic carbon accumulation during this period was a consequence of stagnant bottom water conditions in the hungarian paleogene basin due to salinity stratification this is indicated by low pristane phytane ratios varying from 0 27 to 1 44 enhanced ratios of dimethylated versus trimethylated mttcs 0 14 0 59 and the presence of aryl isoprenoids from 0 4 to 14 1 g g toc a major marine incursion is evidenced by stable isotope ratios of organic matter and carbonates in the uppermost member of the tard clay a transition from brackish towards normal marine conditions is proposed up to 3 anoxic cycles are recognized in the drill core sections separated by minima in pristane phytane ratios and maxima in the depth trends of di tri methylated mttcs and aryl isoprenoid concentrations in combination with the position of maxima of 13c of carbonate and organic matter and an abrupt decrease in perylene concentrations the cycles can be used for intra formational correlation of the tard clay