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Climate and Forecast Mode Simulations for Antarctica:Implications for Temperature and Wind

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Advances in Atmospheric Sciences 2010年第6期27卷 1453-1472页

作者：辛羽飞 Annette RINKE 卞林根 Klaus DETHLOFF 效存德 Moritz MIELKE Chinese Academy of Meteorological Sciences alfred wegener institute for polar and marine research

Climate and forecast mode simulations with the regional climate model HIRlam-ECHAM（HIRHAM） are evaluated over a pan-Antarctic domain. The ability of the model to simulate temperature and wind profiles in the troposphere is quantified by comparing its results with radiosonde data acquired from the Davis station for January and July 2007. Compared to the climate mode, the forecast mode was found to deliver improved results for temperature and wind simulations at the near surface and in the lower troposphere. The main remaining model bias found was the under-representation of low-level wind jets. Based on ensemble simulations, it is shown that a distinct internal variability is inherent in the climate mode simulations, and associated areas of reduced predictability over Antarctica are identified.

关键词： regional climate model Antarctica forecast mode climate mode

中国东部平原湖区现代沉积植物DNA的保存及其与土地利用的关系

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第四纪研究 2025年第1期45卷 213-226页

作者：吴铠李凯林琪贾伟瀚葛亚汶 Kathleen R.Stoof-Leichsenring Ulrike Herzschuh 倪健浙江师范大学生命科学学院金华321004 中国科学院南京地理与湖泊研究所南京210008 polar Terrestrial Environmental Systems research Group Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchPotsdam 14473Germany institute of Environmental Science and Geography University of PotsdamPotsdam 14476Germany 河北师范大学资源与环境科学学院石家庄050024 institute of Biochemistry and Biology University of PotsdamPotsdam 14476Germany

东部平原湖区湖泊众多,但普遍面临富营养化和流域植被破坏问题,使其成为现代生态保护和探究人类活动对湖泊生态系统干扰研究的热点地区。湖泊沉积DNA技术近年来开始被用于湖泊水生植物调查以及流域植被重建等工作,但是该技术在我国东部... 详细信息

东部平原湖区湖泊众多,但普遍面临富营养化和流域植被破坏问题,使其成为现代生态保护和探究人类活动对湖泊生态系统干扰研究的热点地区。湖泊沉积DNA技术近年来开始被用于湖泊水生植物调查以及流域植被重建等工作,但是该技术在我国东部平原湖区的适用性以及植物DNA信号与湖周及流域植被的关系,有待于进一步评估。本研究选择东部平原湖区的22个湖泊为研究对象,利用植物DNA宏条形码技术使用通用植物引物trnL g-h对湖泊表层沉积物中的植物DNA进行扩增并进行高通量测序,结合湖泊形态特征、水体及沉积物理化参数以及湖泊周边土地利用类型等,揭示不同湖泊沉积物中植物DNA保存丰富度的差异及其影响因素,探讨了陆生植物DNA对植被的代表性。结果表明,植物DNA宏条形码共记录230个类群,其中28%的序列可以鉴定至种水平,在分类学分辨率以及鉴定效率上沉积植物DNA相较于花粉分析具有一定优势。与花粉检测的区域性植被信号不同,湖泊沉积植物DNA反映的是局地或者湖泊周边植被组成,可对湖周森林、农田以及建筑用地中的优势植物信号进行区分,凸显了沉积植物DNA在东部平原湖区进行局地植被重建中的适用性。此外,年均降水量以及流域下垫面性质对陆生沉积植物DNA丰度具有重要影响,同时年均温也是影响沉积植物DNA保存的重要因素。综上,在东部平原湖区,湖泊沉积植物DNA技术可为揭示长期人类活动影响下的局地植被组成变化提供支持,但这同样依赖于对湖泊沉积植物DNA现代过程的进一步研究和理解。

关键词：沉积物DNA 植物DNA 宏条形码土地利用类型东部平原湖区

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Pleistocene radiolarian biostratigraphy in the South China Sea

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Science China Earth Sciences 1999年第5期42卷 536-543页

作者：王汝建 Andrea Abelmann alfred wegener institute for polar and marine research 27515 Bremerhaven Germany

Based on a quantitative radiolarian analysis, 5 radiolarian zones (NR1-NR5) have been defined at Core 17957-2 from the South China Sea, considering radiolarian zonations from low latitudes. The absolute age assignment of the radiolarian zones and the ranges of the six marker species is based on the direct correlation with the paleomagnetic and isotopic record, respectively. A comparison of the radiolarian stratigraphic data obtained from Core 17957-2 from the South China Sea with those from the equatorial Pacific and the tropical Indian Ocean shows a close similarity to the ages defined in the equatorial Pacific. The obtained biostratigraphic data provide an excellent tool for further dating of Pleistocene sediments in the China Sea.

关键词： radiolarian biostratigraphy radiolarian zones Pleistocene South China Sea.

Biogenic Sediments and Their Paleoceanographic Implication in West Pacific Warm Pool during the Pleistocene

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Journal of Earth Science 2010年第1期21卷 42-54页

作者：王汝建肖文申 State Key Laboratory of marine Geology Tongji University alfred wegener institute for polar and marine research

Primary productivity has played an important role in the global carbon cycle during the Quaternary. The average Corg/N ratio was 7.0 from the core MD97-2140 in the West Pacific Warm Pool （WPWP） over the last 1 755 ka, which indicates a main contribution of marine organic carbon to the organic matter in the sediments. Large fluctuations in mass accumulation rates （MARs） of biogenics and lithogenics from this core since the marine isotope stage （MIS） 6 reflected the moderate variability in oceanographic condition, while tittle fluctuations in MAR-biogenics and -lithogenics from the MIS 59 to MIS 7 implied the relatively stable and uniform oceanographic condition, although the sea surface temperatures （SSTs） probably fluctuated by ca. 5 ℃. MAR-organic since the MIS 6 increased evidently during the glacial periods, which ascribed to terrestrial inputs, including lithogenic matter and dissolved nutrient, which also contribute to stimulating primary productivity. The results compared among the four cores in the WPWP since the MIS 9 indicate that in the western sector with the shallow thermocline, high primary productivity during the glacial periods was controlled by wind-induced surface water mixing, upwelling, and terrestrial inputs, while in the central and eastern sectors, the little different medium to low productivity might have been made by more intense upweil- ing driven by strong winds because the thicker warm surface water pool and the deeper thermocline prevented nutrient-bearing water from upwelling to upper water column even during the glacial times.

关键词： biogenic sediment paleoceanographic implication West Pacific Warming Pool Pleistocene.

Abrupt variations of the radiolarian fauna at Mid-Pleistocene climate transition in the South China Sea

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Chinese Science Bulletin 2000年第10期45卷 952-955页

作者： Andrea Abelmann alfred wegener institute for polar and marine research 27515 BremerhavenGermany

Based on a detailed study of the radiolarian fauna, the abundance pattern of planktic foraminifera as well as on isotope and sedimentological records, the Mid-Pleistocene climate transition as a multiple transition phenomenon could be recognized at Core 17957-2 from the South China Sea. Distinct changes in the radiolarian/foraminfera ratio, the coarse fraction and the radiolarian assemblages can be related to the global climate cooling observed at the Mid-Pleistocene revolution (MPR) around 900 ka. A pronounced southward shift of the North Equatorial Current that leads to lower sea-surface temperatures in the South China Sea is documented by the shift of tropical to subtropical radiolarian assemblages at 900 ka. Increasing radiolarian abundance after the MPR can be interpreted as a result of stronger upwelling and nutrient supply. These abrupt variations could result from the northern trade wind system and East Asian monsoon circulation.

关键词： radiolarian fauna abrupt variations 900 ka Mid-Pleistocene climate transition South China Sea.

Gastric carboxylesterases of the edible crab Cancer pagurus (Crustacea, Decapoda) can hydrolyze biodegradable plastics

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Emerging Contaminants 2024年第1期10卷 80-89页

作者： Lukas Miksch Lars Gutow Reinhard Saborowski alfred wegener institute Helmholtz Centre for Polar and Marine ResearchAm Handelshafen 1227570BremerhavenGermany

A promising strategy to counteract the progressing plastic pollution of the environment can involve the replacement of persistent plastics with biodegradable *** polymers are enzymatically degradable by various hydrolytic ***,these materials can reach the environment in the same way as conventional ***,they are accessible to terrestrial,freshwater,and marine *** ingested by marine organisms,highly active enzymes in their digestive tracts may break down biodegradable *** incubated microparticles of five different biodegradable plastics,based on polylactictic acid(PLA),polybutylene succinate(PBS),polybutylene adipate terephthalate(PBAT)and polyhydroxybutyrate-co-valerate(PHBV),in-vitro with the gastric fluid of the edible crab Cancer pagurus and evaluated the hydrolysis rates by pH Stat titration.A plastic blend of PLA with PBAT showed the highest hydrolysis *** enzymes in the gastric fluid of crabs were separated by anion exchange *** with carboxylesterase activity were identified using fluorescent methylumbelliferyl(MUF)-*** fractions with high carboxylesterase activity also hydrolyzed a PLA/PBAT plastic *** showed molecular masses of 40–45 kDa as determined by native gel electrophoresis(SDS-PAGE).Our study demonstrated that digestive carboxylesterases in the gastric fluid of *** exhibit a high potential for hydrolyzing certain biodegradable *** esterases are common in the digestive tract of organisms,it seems likely that other invertebrates possess the ability to hydrolyze biodegradable plastics.

关键词： Biodegradable plastics Microplastics Crustaceans Ingestion Enzymes Enzymatic degradation

Evaluating the Mechanism of Tropical Expansion Using Idealized Numerical Experiments

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Ocean-Land-Atmosphere research 2023年第1期2卷 44-56页

作者： Hu Yang Gerrit Lohmann Xiaoxu Shi Juliane Müller alfred wegener institute Helmholtz Centre for Polar and Marine ResearchBremerhavenGermany University of Bremen Center for Marine Environmental SciencesMARUMBremenGermany

A wide range of evidence reveals that the tropical belt is *** mechanisms have been proposed to contribute to this expansion,some of which even contradict each *** study of Yang et *** that the poleward advancing mid-latitude meridional temperature gradient(MTG),originating from enhanced subtropical ocean warming,plays a leading role in driving tropical ***,the abrupt4xCO_(2) experiment indicates that tropical expansion occurs at a faster rate than is indicated by changes related to ocean temperature *** idealized amip4K experiment illustrates that without introducing any ocean warming pattern,uniform ocean surface warming also drives tropical *** results based on these idealized experiments seem to contradict the hypothesis proposed by Yang et *** this study,we revisit these 2 experiments and show that both experiments actually support the hypothesis that MTG migration is driving tropical *** specifically,in the abrupt4xCO_(2) experiment,although the rate of ocean warming is relatively slow,the poleward shift of the MTG is as rapid as tropical *** the amip4K experiment,although ocean surface warming is uniform,the heating effect of the ocean on the atmosphere is nonuniform because of the nonlinear relationship between temperature,evaporation,and thermal *** nonuniform oceanic heating to the atmosphere introduces a poleward shift of the MTG within the upper troposphere and drives a shift in the jet *** conducting an additional idealized experiment in which tropical expansion occurs under both a migrating MTG and a cooling climate,we argue that the migration of the MTG,rather than global warming,is the key mechanism in driving tropical expansion.

关键词： warming ocean tropical

The impact of salps(Salpa thompsoni)on the Antarctic krill population(Euphausia superba):an individual-based modelling study

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Ecological Processes 2023年第1期12卷 680-695页

作者： Bruno Walter Pietzsch Aaron Schmidt Jürgen Groeneveld Dominik Bahlburg Bettina Meyer Uta Berger Faculty of Environmental Sciences Institute of Forest Growth and Forest Computer SciencesTechnische Universität Dresden01062 DresdenGermany Department of Ecological Modelling Helmholtz Centre for Environmental Research-UFZLeipzigGermany Section polar Biological Oceanography Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchBremerhavenGermany institute for Chemistry and Biology of the marine Environment(ICBM) Carl-Von-Ossietzky UniversityOldenburgGermany helmholtz institute for marine Functional Biodiversity(HIFMB) OldenburgGermany

Background Krill(Euphausia superba)and salps(Salpa thompsoni)are key macrozooplankton grazers in the Southern Ocean ***,due to differing habitat requirements,both species previously exhibited little spatial *** ongoing climate change-induced seawater temperature increase and regional sea ice loss,salps can now extend their spatial distribution into historically krill-dominated areas and increase rapidly due to asexual reproduction when environmental conditions are *** the potential effects on krill is crucial,since krill is a species of exceptional trophic significance in the Southern Ocean food *** impacts on krill could trigger cascading effects on its predators and *** address this question,we combined two individual-based models on salps and krill,which describe the whole life cycle of salp individuals and the dynamic energy budget of individual *** resulting new model PEKRIS(PErformance of KRIll ***)simulates a krill population for 100 years under varying chlorophyll-a concentrations in the presence or absence of *** All of the investigated krill population properties(abundance,mean length,and yearly egg production)were significantly impacted by the presence of *** the other hand,salp density was not impacted if krill were *** medians of krill population properties deviated during variable maximum chlorophyll-a density per year when salps were introduced by−99.9%(−234 individuals per 1000 m3)for krill density,−100%(−22,062 eggs per 1000 m3)for krill eggs and−0.9%(−0.3 mm)for mean length of *** If both species compete for the same food resource in a closed space,salps seem to inhibit krill *** simulation studies should investigate whether this effect prevails if different phytoplankton sizes and consumption preferences of krill are ***,direct predation of the two species or consumption of krill fecal pellets by salps could c

关键词： Euphausia superba Salpa thompsoni Individual-based model Food competition Population dynamics DEB theory

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Abrupt changes of radiolarian fauna at 600 and 120 ka B. P. in the southern South China Sea and their paleoceanographic implications

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Acta Oceanologica Sinica 2000年第3期19卷 131-138页

作者：王汝建 Andrea Abelmann Laboratory of marine Geology Ministry of Education Tongji University Shanghai 200092China alfred wegener institute for polar and marine research 27515 BremerhavenGermany

Abrupt changes in radiolarian composition are discovered over the last 600 and 120 ka B. P. based on quantitative analyses of radiolarians in ~ 17957 - 2 of the southern South China Sea. The distinct changes at 600 ka B. P. could correspond to the onset of the 100 ka cycle during the glacial and interglacial periods. This abrupt change in the 100 ka cyclicity at 600 ka B. P. occurred also in the magnetic susceptibility signal that is obtained from and paleosol sequences of the China Loss Plateau. The larger amplitude and stronger cyclicity in the susceptibility signal after 600 ka B. P. reflect the prominent change in the intensity of the monsoon, induced by an enhancement of the momsoon circula- tion. Stronger seasonality during the glacial period in the South China Sea, resulted from strengthening of winter monsoon, might lead to the changes in the radiolarian composition at 600 and 120 ka B. P. It can be suggested that only species adapted to a broader temperature range might have been able to live in this environment. Therefore, the abrupt changes in radiolarian composition at 600 and 120 ka B. P. could be attributed to the stronger so differences between summer and winter that were caused by the striking change in the intensity of the monsoon circulation.

关键词： Radiolarian fauna abrupt changes 600 and 120 ka B. P. East Asian monsoon South China Sea