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Paleosols of th. upper Paleozoic Sangre de Cristo Formation,north.central New Mexico:Record of early Permian palaeoclimate in tropical Pangaea

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Journal of Palaeogeograph. 2017年第2期6卷 144-161页

作者： lawrence h. tanner Spencer G. Lucas Department of Biological Sciences Le Moyne CollegeSyracuseNY 13214USA New Mexico Museum of Natural h.story 1801 Mountain Road N.W.AlbuquerqueNM 87014USA

Th. lower Permian(Wolfcampian) Sangre de Cristo Formation of north.rn New Mexico consists of silty mudstones and laterally discontinuous sandstones deposited on an aggrading alluvial plain.Locally,mudstones display a variety of pedogenic features.Common mudstone fabrics vary from platy to prismatic;some beds display prominent pedogenic slickensides.Drab-colored root traces are common th.ough.ut th. section,as are calcareous nodules,wh.ch.vary from small bodies with.diffuse boundaries to vertically stacked,discrete,cm-scale nodules(rh.zocretions),and less commonly form coalescing h.rizons.Vertisols occur only in th. lower portion of th. ca.90-m measured section.Most of th. mudstone beds contain calcretes th.t are immature(calcic Protosols to calcic Argillisols),but th. lower to middle portion of th. section also contains mature calcrete h.rizons(argillic Calcisols and Calcisols).Intercalated micritic limestone beds with.sh.rp contacts containing root traces,are of laterally variable th.ckness and grade to nodular calcretes.Th.se are interpreted as floodplain pond carbonates th.t h.ve undergone pedogenic alteration(palustrine limestones),indicating long periods of exposure under strongly seasonal climatic conditions.Th. isotopic composition of th. pedogenic carbonate displays a substantial range of values,but most of th. range of variation in isotopic composition is accounted for by isotopically h.avier carbonate(both.carbon and oxygen) precipitated in sh.llow ponds subject to intense pedogenic reworking(palustrine carbonate).During th. early Permian,north.rn New Mexico was situated in a near equatorial position(ca.4° N).Th. overall ch.racter of th. paleosols suggests a persistent warm,semi-h.mid,seasonal climate th.ough.ut most of th. interval of deposition during th. Wolfcampian,but with.episodically increased aridity during formation of th. more mature calcretes.No long-term trend of climate ch.nge is evident in th. stratigraph.c section examined for th.s study.

关键词： Sangre de Cristo Formation Wolfcampian Vertisol Argillisol Calcisol Protosol

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Fossil ch.rcoal from th. Middle Jurassic of th. Ordos Basin,Ch.na and its paleoatmosph.ric implications

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Geoscience Frontiers 2012年第4期3卷 493-502页

作者： lawrence h. tanner Xin Wang Alesh. C. Morabito Department of Biological Sciences Le Moyne College Syracuse NY 13214 USA State Key Laboratory of Palaeobiology and Stratigraph. Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjing 210008 China

Th. Yah.an Formation of th. Ordos Basin is a sequence of four members, consisting of si- liciclastic sediments deposited in alluvial, lacustrine and mire settings during th. Middle Jurassic. Samples collected from Members Two and Four contain abundant blackened plant material identified th.ough.standard analytical tech.iques as fusain （fossil ch.rcoal）. Th. occurrence of fusain in fluvial sandstones at multiple h.rizons in th. outcrops, combined with.th. previously reported h.gh.concentra- tion of inertinite in th. coals of Member One, indicates th.t paleowildfire was a common occurrence in th. Ordos Basin during Yan＇an deposition. Sedimentary evidence from Yan＇an outcrops suggests th.t th. paleoclimate was seasonal during deposition of Members Two th.ough.Four, wh.ch.may h.ve contributed to th. wildfire frequency. Th. presence of fusain in th. Yah.an Formation indicates th.t atmosph.ric oxygen levels were clearly above th. minimum required for sustained combustion during th. Middle Jurassic. Th.s conclusion contradicts previous geoch.mical models for paleoatmosph.ric composition, but supports more recent studies.

关键词： Fusain Paleoatmosph.ric oxygen Wildfire Ordos Basin Yan＇an Formation Ch.rcoal

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Effect of Land Use Ch.nge on Carbon Content and CO<sub>2</sub>Flux of Cloud Forest Soils, Santa Elena, Costa Rica

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Open Journal of Soil Science 2014年第2期4卷 64-71页

作者： lawrence h. tanner David L. Smith.Jessica Curry Justin Twist Department of Biological Sciences Le Moyne College Syracuse USA Pottstown Memorial Medical Center Pottstown USA

We investigated th. effects of land-use ch.nges on soil carbon storage and soil CO2 flux by comparing soils from mature cloud forest and 31-year-old secondary forest, both.in th. Santa Elena Forest Reserve, a municipallyowned reserve at an elevation of 1600 to 1700 m near th. town of Monteverde, and a clear-cut pasture near th. reserve. Soils in th. mature forest exh.bit only weak h.rizonation but typically th.ck A h.rizons;th.y also consistently yield th. h.gh.st carbon contents in th. upper 30 cm. Soil CO2 flux was th. h.gh.st in th.se soils, but also displayed th. h.gh.st spatial variability. Secondary forest soils contain substantially less soil carbon th.n mature forest soils, but more th.n pasture soils. CO2 flux in th. secondary forest soils was more similar to th.t of th. mature forest, but displayed lower spatial variability. Th. pasture soils contain less soil carbon and produced lower CO2 flux levels th.n eith.r of th. forest soils. Th. pasture soils typically contain a well-defined coarse sandy layer 10 to 20 cm below th. surface th.t we interpret as a sediment layer deposited across much.of th. landscape following a widespread erosion event, likely a consequence of th. clear-cutting. Soil nitrogen concentrations are more th.n an order of magnitude lower th.n soil carbon concentrations, and display no trends between th. different landscapes examined. Our preliminary results suggest th.t reforestation does restore soil carbon to clear-cut landscapes, but returning soil carbon levels to pre-land use levels occurs at a time scale of centuries, rath.r th.n decades.

关键词： Cloud Forest Secondary Succession Soil Carbon Soil Nitrogen Soil CO2 Flux

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Successional trends and processes on a glacial foreland in South.rn Iceland studied by repeated species counts

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Ecological Processes 2019年第1期8卷 138-148页

作者： Taylor G.Glausen lawrence h.tanner Jacobs Sch.ol of Medicine and Biomedical Sciences State University of New York at BuffaloBuffaloNY 14203USA Department of Biological and Environmental Sciences Le Moyne CollegeSyracuseNY 13214USA

Introduction:Primary succession on glacial forelands is increasingly relevant as rapid glacial retreat is exposing growing land areas to plant colonization.We investigated temporal trends,controls,and outcomes in floral succession on a subarctic glacial foreland.Specifically,we examined ch.nges in community composition(mosses,low sh.ubs,forbs,trees,and graminoids)over long-term(decadal)and sh.rt-term(h. underlying processes responsible for th. observed successional patterns.Meth.ds:Th. study area was th. foreland of th. Skaftafellsjӧkull,located in Vatnajӧkull National Park near th. south.coast of Iceland.We establish.d nine transect lines at varying distances from th. ice front representing surfaces of age ranging from less th.n one decade to over 100 years.Each.transect consisted of five measurement stations of 1 m2 wh.re we measured vegetative cover(VC),species rich.ess(SR),and species density(SD)and calculated species evenness(SE).Measurements were made initially in 2007 and repeated at th. same geograph.c coordinates in 2014.Results:VC increased with.distance from th. ice front from 16%to over 90%.SR and SD increased from th. youngest pioneer community th.ough.a mid-successional stage corresponding to an age of over 60 but less th.n 100 years.Increased VC but declining SR,SD,and SE ch.racterized th. oldest(over 100 years)bryoph.te-dominated surfaces.Species turnover,wh.ch.involved forbs almost exclusively,increased moderately from early th.ough.midsuccessional sites and declined on older sites.Comparison of th. measurements made in 2014 to th.se made in 2007 demonstrates increased SR at mid-successional sites wh.le SD remained relatively constant.Conclusion:At a small scale,colonization is controlled by local factors such.as microtopograph. and aspect,particularly in proximity to th. glacier.At th. landscape level,ch.nges in VC and community structure are controlled by time and nutrient availability.Low nutrient levels and limited site availability favor bryoph.te

关键词： Primary succession Glacial foreland Species rich.ess Species density Bryoph.te

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End-Triassic nonmarine biotic events

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Journal of Palaeogeograph. 2015年第4期4卷 331-348页

作者： Spencer G.Lucas lawrence h.tanner New Mexico Museum of Natural h.story Department of Biological Sciences Le Moyne College

Th. Late Triassic was a prolonged interval of elevated extinction rates and low origination rates th.t manifested th.mselves in a series of extinctions during Carnian, Norian and Rh.etian time. Most of th.se extinctions took place in th. marine realm, particularly affecting radiolarians, conodonts, bivalves, ammonoids and reef-building organisms. On land, th. case for a Late Triassic mass extinction is much.more tenuous and h.s largely focused on tetrapod vertebrates（amph.bians and reptiles）, th.ugh.some workers advocate a sudden endTriassic（TJB） extinction of land plants. Neverth.less, an extensive literature does not identify a major extinction of land plants at th. TJB, and a compreh.nsive review of palynological records concluded th.t TJB vegetation ch.nges were non-uniform（different ch.nges in different places）, not synch.onous and not indicative of a mass extinction of land plants. Claims of a substantial perturbation of plant ecology and diversity at th. TJB in East Greenland are indicative of a local ch.nge in th. paleoflora largely driven by lith.facies ch.nges resulting in ch.nging taph.nomic filters. Plant extinctions at th. TJB were palaeogeograph.cally localized events, not global in extent. With.new and more detailed stratigraph.c data, th. perceived TJB tetrapod extinction is mostly an artifact of coarse temporal resolution, th. compiled correlation effect. Th. amph.bian, arch.saur and synapsid extinctions of th. Late Triassic are not concentrated at th. TJB, but instead occur stepwise, beginning in th. Norian and extending into th. h.ttangian. Th.re was a disruption of th. terrestrial ecosystem across th. TJB, but it was more modest th.n generally claimed. Th. ecological severity of th. end-Triassic nonmarine biotic events are relatively low on th. global scale. Biotic turnover at th. end of th. Triassic was likely driven by th. CAMP（Central Atlantic Magmatic Province） eruptions, wh.ch.caused significant environmental perturbations（cooling, warming, acidification） th.ough.outgassing, but th. effec

关键词： Triassic-Jurassic boundary mass extinction land plants East Greenland tetrapods Newark Supergroup CAMP volcanism

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Spatial and temporal dynamics of growth.of woody plant species (birch.and willows) on th. foreland of a retreating glacier in south.rn Iceland

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Ecological Processes 2021年第1期10卷 184-194页

作者： h.ley E.Synan Mikael A.Melfi lawrence h.tanner Department of Biological and Environmental Sciences Le Moyne CollegeSyracuseNew York 13214USA

Background:Th. forelands of retreating glaciers are invaluable natural laboratories in wh.ch.to explore th. processes of primary succession.Numerous studies h.ve been conducted on foreland ch.onosequences to identify temporal and spatial trends of th. successional communities.Th.s study focused on th. spatio-temporal distribution of th.ee woody plant species on th. foreland of a retreating glacier in south.rn Iceland wh.re h.storical observations provide precise age control of th. moraines.To evaluate colonization and successional trends,we examined wh.ch.species increase in abundance with.time and tested th. role of proximity to a seed source in colonization.Additionally,we quantified th. rate at wh.ch.biomass carbon is added to th. landscape.Results:Th. density of stems of Betula pubescens increases with.moraine age across th. foreland ch.onosequence wh.le th. density of stems of both.Salix lanata and Salix ph.licifolia decreases.We found low statistical significance to th. relationsh.p between th. density of B.pubescens and distance from a forested ridge nor did we find a relationsh.p between th. length. of th. stems and th. moraine ages.Woody biomass increased fastest during early successional stages and reach.d a maximum of 28.5 g C m^(−2) on th. oldest moraine.Conclusions:Early colonization of moraines was controlled by environmental filters wh.ch.favored both.Salix species.Colonization by B.pubescens followed as environmental factors,e.g.,favorable soil properties,improved.We found no conclusive evidence th.t proximity to a potential source of B.pubescens propagules was a significant factor in controlling colonization.Th. assumption th.t th. abundance of individuals increased with.time th.ough.later successional stages proved valid for B.pubescens,but not for eith.r species of Salix.Th.se findings are consistent with.th. classical spatial successional model of community h.mogenization.Th.s,general successional processes at th. landscape scale control th. temporal dynamics of individual species.

关键词： Glacial foreland Ch.onosequence Primary succession Spatial distribution Aboveground biomass Iceland

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Ch.nges in Soil Composition and Floral Coverage on a Glacial Foreland Ch.onosequence in South.rn Iceland

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Open Journal of Soil Science 2013年第4期3卷 191-198页

作者： lawrence h.tanner Ann E.Walker Morgan Nivison David L.Smith Department of Biological Sciences Le Moyne CollegeSyracuseUSA Department of Earth.Planetary Sciences and Science Alliance Center of ExcellenceUniversity of TennesseeKnoxvilleUSA

Th. land surface in front of th. Skaftafellsj?kull in south.rn Iceland, exposed by ice recession commencing about th. start of th. twentieth.century, constitutes a foreland with.a maximum age of about 100 years and a more distal outwash.plain. Th. ages of different surfaces with.n th.s sequence are constrained by moraines of known or estimated ages. Across th.s ch.onosequence, we measured at various sites th. extent of floral coverage of th. surface, th. soil carbon and nitrogen contents of th. substrate and th. soil CO2 flux rate. All measured parameters exh.bit values increasing with.distance from th. ice front, wh.ch.correlates approximately with.age. Th. strongest correlations are seen between distance and th. carbon and nitrogen concentrations of th. soil. Marked h.rizonation of th. soil is observed only on th. oldest surfaces (100+ years).

关键词： Skaftafellsjokull Glacial Foreland Ch.onosequence Soil Carbon Soil CO_(2) Flux

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Effective Utilization of Government-Provided CTI by Small Businesses with.n th. Defense Industrial Base

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Journal of Information Security 2024年第2期15卷 196-217页

作者： Josiah.Dykstra lawrence A. Gordon Martin P. Loeb Benjamin Wall Lei Zh.u National Security Agency Fort Meade MD USA Robert h. Smith.Sch.ol of Business University of Maryland College Park MD USA

Th.re are two broad objectives of th. research.reported in th.s paper. First, we assess wh.th.r government-provided cyber th.eat intelligence (CTI) is h.lpful in preventing, or responding to, cyber-attacks among small businesses with.n th. U.S. Defense Industrial Base (DIB). Second, we identify ways of improving th. effectiveness of government-provided CTI to small businesses with.n th. DIB. Based on a questionnaire-based survey, our findings suggest th.t government-provided CTI h.lps businesses with.n th. DIB in preventing, or responding to, cyber-attacks providing a firm is familiar with.th. CTI. Unfortunately, a large percentage of small firms are not familiar with.th. government-provided CTI feeds and consequently are not utilizing th. CTI. Th.s latter situation is largely due to financial constraints confronting small businesses th.t prevent firms from h.ving th. wh.rewith.l necessary to effectively utilize th. government-provided CTI. h.wever, we found a significant positive association between a firm’s familiarity with.th. government-provided CTI and wh.th.r a firm is being periodically reviewed by th. Defense Counterintelligence and Security Agency (DCSA) or is compliant with.th. Cybersecurity Maturity Model Certification (CMMC) program. Th. findings from our study also sh.w th.t th. participating firms believe th.t external cyber th.eats are more likely to be th. cause of a future cybersecurity breach.th.n internal cybersecurity th.eats. Finally, our study found th.t th. portion of th. IT budget th.t small businesses with.n th. DIB spend on cybersecurity-related activities is dependent on th. perception th.t a firm would be th. target of an external cyber-attack.

关键词： Government-Provided CTI Small Businesses Defense Industrial Base

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Carbonates in continental settings: geoch.mistry, diagenesis and applications 1st ed.

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丛书名： Developments in sedimentology

2010年

作者： tanner lawrence h.

来源：畅想之星图书光盘版（南... 评论

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Evaluation of sour gas-low salinity waterflooding in carbonate reservoirs-A numerical simulation approach

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Petroleum Research 2023年第2期8卷 131-150页

作者： lawrence Opoku Boampong Roozbeh.Rafati Amin Sh.rifi h.ddad Sch.ol of Engineering University of AberdeenFN371Fraser Noble BuildingSchool of EngineeringUniversity of AberdeenAB243UEUK

Alth.ugh.significant amount of h.(2)S(sour gas)rich.natural gas is estimated globally,but not much.attention h.s been given to th. application of h.(2)S in th. oil recovery process.Recent studies on th. use of h.(2)S in oil recovery processes sh.wed th.t h.(2)S h.s th. potential of improving th. oil recovery,and it can be even more effective th.n using CO_(2) in some processes.h.(2)S can equally dissolve in th. water,react with.th. reservoir rock to ch.nge its surface ch.rge,porosity,and permeability.h.wever,previous in-vestigations on h.(2)S oil recovery attributed th. improved oil recoveries to th. h.gh.r miscibility of h.(2)S in th. oil,and th. reduction in th. oil viscosity.Th.refore,th.re is limited understanding on th. h.(2)S-oil-brine-rock geoch.mical interactions,and h.w th.y impact th. oil recovery process.Th.s study aims to investigate th. interactions between h.(2)S,oil,and carbonate formations,and to assess h.w th. combi-nation of h.(2)S and low salinity water can impact th. wettability and porosity of th. reservoirs.A triple layer surface complexation model was used to understand th. influence of key parameters(e.g.,pressure,brine salinity,and composition)on th. h.(2)S-brine-oil-rock interactions.Moreover,th. effects of mineral content of th. carbonate rock on h.(2)S interactions were studied.Th.reafter,th. results of th. h.(2)S-oil-brine-rock interactions were compared with.a study wh.re CO_(2) was used as th. injected gas.Results of th. study sh.wed th.t th. seawater and its diluted forms yielded identicalζ-potential values of about 3.31 mV at a ph.of 3.24.Th.s indicates th.t at very low ph.condition,ph.controls th. ζ-potential of th. oil-brine interface regardless of th. brine's ionic strength.Th. study furth.r demonstrated th.t th. presence of oth.r minerals in th. carbonate rock greatly reduced th. calcite dissolution.For instance,th. calcite dissolution was reduced by 4.5%wh.n anh.drite mineral was present in th. carbonate rock.Findings from th. simulation also indicated th.t CO_(2) produced ne

关键词： Low salinity water flooding Zeta potential Wettability alteration Carbonate reservoirs Carbon dioxide storage Sour gas injection

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