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Journal of Palaeogeography 2019年第1期8卷 43-67页

作者： Dimiter Ivanov Maria Lazarova institute of biodiversity and ecosystem Research Bulgarian Academy of Sciences

The results of palynological studies on the late Miocene freshwater deposits of the Tundzha Basin(Southeast Bulgaria, SE Europe) are presented. The basin is relatively well known in terms of geology and *** age of sediments in the Tundzha Basin ranges between the late Miocene to the Pliocene, based on mammal and diatom fossils. We carried out a palynological analysis of clayey sediments interlayered with coal beds from four cores and from one outcrop, aiming to obtain information about the composition and the structure of fossil vegetation. The ratios between the main floristic elements and the composition of the fossil flora are analysed and discussed from a palaeoecological point of view. Several main vegetation palaeocommunities were recorded:swamp forests, mixed mesophytic, communities of aquatic plants, and herbaceous palaeocoenoses. The changes in vegetation and in plant diversity are identified. The palaeoclimate analysis indicates a warm temperature climate with high rainfall and mild winter temperatures, without seasonal drier conditions. The early Pontian climate was about 3–4 ℃ warmer than today, with rainfalls per year at least 300 mm higher than today. The results of palaeoecological analysis of the flora and of the quantitative palaeoclimate data show that the climate in the Southeast Bulgaria indicates a climate change towards slight cooling and some drying. This event is consistent with the period of accumulation of the upper, undivided part of the Elhovo Formation.

关键词： Palynology Palaeobotany Coexistence approach Neogene Tundzha Basin Bulgaria

Selective Extraction Methods for Aluminium,Iron and Organic Carbon from Montane Volcanic Ash Soils

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Pedosphere 2011年第5期21卷 549-565页

作者： B.JANSEN F.H.TONNEIJCK J.M.VERSTRATEN Earth Surface Science Research Group Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam IUCN National Committee of the Netherlands Plantage Middenlaan 2C

Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon *** the central role of Al and Fe in stabilizing organic matter in volcanic ash soils,we assessed various extraction methods of Al,Fe,and C fractions from montane volcanic ash soils in northern Ecuador,aiming at elucidating the role of Al and Fe in stabilizing soil organic matter(SOM).We found extractions with cold sodium hydroxide,ammonium oxalate/oxalic acid,sodium pyrophosphate,and sodium tetraborate to be particularly *** of these methods yielded information about the role of the mineral phase in stabilizing organic matter and the differences in type and degree of complexation of organic matter with Al and Fe in the various horizons and soil *** tetraborate extraction proved the only soft extraction method that yielded simultaneous information about the Al,Fe,and C fractions *** also appeared to differentiate between SOM fractions of different *** fractions of copper chloride-and potassium chloride-extractable Al were useful in assessing the total reactive and toxic Al fractions,*** classical subdivision of organic matter into humic acids,fulvic acids,and humin added little useful *** use of fulvic acids as a proxy for mobile organic matter as done in several model-based approaches seems invalid in the soils studied.

关键词： complexation global carbon cycle soft extraction method soil organic matter

Root-derived organic matter confines sponge community composition in mangrove ecosystems

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Ecological Processes 2013年第1期2卷 139-142页

作者： Ellard R Hunting Selma M Ubels Michiel HS Kraak Harm G van der Geest University of Amsterdam Aquatic Ecology and EcotoxicologyInstitute for Biodiversity and Ecosystem Dynamics(IBED-AEE)Sciencepark 904NL-1098 XHAmsterdamThe Netherlands

Introduction:Caribbean mangrove-associated sponge communities are very distinct from sponge communities living on nearby reefs,but the mechanisms that underlie this distinction remain *** has been hypothesized that dissolved organic matter(DOM)leaching from mangrove roots and the ability of mangrove-associated spongebacterial consortia to degrade mangrove DOM may cause this ***:This study tested whether mangrove DOM,leaching from mimicry substrates or directly injected in sponge tissue,affected the performance of a reef and a mangrove sponge ***:Controls and the mangrove sponge remained unaffected by mangrove DOM leaching from mimicry substrates or directly injected in sponge tissue,but the reef species showed substantial necrosis when exposed to mangrove ***:Results presented in this study suggest that mangrove DOM confines the composition of sponge communities in mangrove ecosystems,explaining the exclusion of typical reef species and the adjacent occurrence of distinct sponge communities.

关键词： Dissolved organic matter Mangrove root Necrosis Polyphenols Sponges Reef

Habitat preferences of diurnal raptors in relation to human access to their breeding territories in the Balkan Mountain Range,Bulgaria

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Avian Research 2021年第3期12卷 307-316页

作者： Nadejda Djorgova Dimitar Ragyov Valko Biserkov Jordan Biserkov Boris P.Nikolov institute of biodiversity and ecosystem Research Bulgarian Academy of Sciences2 Gagarin Street1113 SofiaBulgaria

Background:In this study we examined the habitat preferences of three diurnal raptors in relation to human *** aimed to identify the selection of breeding habitat by the Golden Eagle(Aquila chrysaetos),the Long-legged Buz-zard(Buteo rufinus),and the Peregrine Falcon(Falco peregrinus)in response to site accessibility by humans,and in turn,the response of these species to human ***:Data about the nest locations were *** and maps were created using ***“least cost path”was defined using the Cost Path ***:The lowest values of the Cost Path were established for Long-legged Buzzard and the highest values were estimated for Golden *** Cost Path values for Peregrine Falcon were ***:The Long-legged Buzzard could be considered as the most tolerant to human presence in its breeding *** Golden Eagle have the lowest degree of tolerance and the Peregrine Falcon is ranked in an intermedi-ate position compared to the other two species,but closer to Golden Eagle.

关键词： Anthropogenic impact Golden Eagle Least cost path Long-legged Buzzard Peregrine Falcon

Contact and hybrid zone hotspots and evolution of birds in the Middle East

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Progress in Natural Science:Materials International 2007年第9期17卷 1114-1118页

作者： Mansour Aliabadian Mohammad Kaboli Bahram Kiabi Vincent Nijman institute for biodiversity and ecosystem dynamics Zoological MuseumUniversity of Amsterdam1090 GT AmsterdamThe NetherlandsDepartment of BiologyFaculty of SciencesFeredowsi UniversityMashadIran Department of Fishery and Environment Faculty of Natural ResourcesTehran UniversityIran Department of Biology Faculty of SciencesUniversity of Shahid BeheshtiTehranIran institute for biodiversity and ecosystem dynamics Zoological MuseumUniversity of Amsterdam1090 GT AmsterdamThe Netherlands

The Middle East is an important contact zone for a considerable number of bird taxa from the western and eastern Palearctic and from the great Saharo-Sindian desert *** WORLDMAP software,we analyzed the geographical distribution of secondary contact zones for parapatric species pairs of birds in the Middle *** identified 56 species(29 species pairs)that make contact in the Middle *** species pairs belong to three orders,***,Piciformes,and *** half(46%)of these species pairs hybridize in their contact *** contact zones occur over a large part of northern Middle East,spatially they were not evenly *** zone richness was highest in the mountain ranges south of the Caspian Sea and the *** hottest hotspots,where up to nine bird species pairs occur sympatrically,are situated in north-eastern Iran and *** discuss the relevance of these hotspots for improving our understanding of the biogeography and evolution of the avifauna in the Middle East.

关键词： contact zone hybridisation Middle East parapatry species-pairs zoogeography

Influence of Organo-Metal Interactions on Regeneration of Exhausted Clay Mineral Sorbents in Soil Columns Loaded with Heavy Metals

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Pedosphere 2017年第3期27卷 579-587页

作者： Yasser REFAEY Boris JANSEN Pim DE VOOGT John R.PARSONS Abdel-Hamid EL-SHATER Abdel-Aziz EL-HADDAD Karsten KALBITZ institute for biodiversity and ecosystem dynamics (IBED) University of Amsterdam Geology Department Faculty of Science Sohag University Soil Resources and Land Use Institute of Soil Science and Site Ecology Faculty of Environmental Sciences Technical University Dresden

Natural clay minerals can play an important role in crude remediation of wastewater polluted with the heavy metals （HMs） Cu, Zn and Ni. The presence and timing of ddition of natural dissolved organic matter （DOM） have a significant effect on the HM removal by clay mineral sorbents. However, the influence of the presence of DOM on the remediation of the used clay mineral sorbents once saturated with HMs is largely unknown. To resolve this, clay mineral-rich soil column of varying composition, loaded （i） with Cu, Zn and Ni only, （ii） first with DOM followed by Cu, Zn and Ni, or （iii） with DOM, Cu, Zn and Ni simultaneously, was used in a set of desorption experiments. The soil columns were leached with 0.001 mol L-1 CaCI2 dissolved in water as control eluent and 0.001 tool L-1 CaC12 dissolved in DOM as treatment eluent. During the preceding loading phase of the sorbent, the timing of DOM addition （sequential or concurrent with HMs） was found to have a significant influence on the subsequent removal of the HMs. In particular when the column was loaded with DOM and HMs simultaneously, largely irreversible co-precipitation took place. Our results indicate that the regeneration potential of clay mineral sorbents in wastewater treatment will be significantly reduced when the treated water is rich in DOM. In contrast, in manured agricultural fields （where HMs enter together with DOM）, HM mobility will be lower than expected from interaction dynamics of HMs and clay minerals.

关键词： dissolved organic matter heavy metal mobility remediation timing of addition wastewater treatment

Evaluation of Reynolds-averaged Navier-Stokes turbulence models in open channel flow over salmon redds

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Journal of Hydrodynamics 2024年第4期36卷 741-756页

作者： Bishal Bhattarai Brandon Hilliard Daniele Tonina William J.Reeder Ralph Budwig Benjamin T.Martin Tao Xing Department of Mechanical Engineering University of IdahoMoscowUSA Center for Ecohydraulics Research University of IdahoBoiseUSA institute for biodiversity and ecosystem dynamics University of AmsterdamAmsterdamThe Netherlands Hamm School of Engineering University of MaryBismarckUSA

This study evaluates computational fluid dynamics(CFD)turbulence closures for Reynolds-averaged Navier-Stokes(RANS)equations against experimental data to model complex open channel flows,like those occurring over dune-shaped salmon spawning nests called"redds".Open channel flow complexity,characterized by near-bed turbulence,adverse pressure,and free surfaces,requires suitable turbulence closure capable of capturing the flow structure between streambed and water *** evaluated three RANS models:Standard k-,shear-stress transport(SST)k-@and realizable k-,along with four wall treatments for the realizable k-:Standard,and scalable wall functions,enhanced wall treatment,and an unconventional closure combining standard wall function with near-wall mesh resolving the viscous *** all models generally capturing the bulk flow characteristics,considerable discrepancies were evident in their ability to predict specific flow features,such as flow *** realizable k-model,with standard wall function and mesh resolving viscous sublayer,outperformed other closures in predicting near-wall flow separations,velocity fields,and free surface *** realizable k-model with a log-layer resolved mesh predicted the free surface elevation equally well but lacked precision for near-wall *** SST k-@model outperformed in predicting turbulent kinetic energy and provided better predictions of the near-boundary velocity distributions than realizable k-closure with any of the conventional wall treatments but overestimated the separation vortex *** standard k-o model also overestimated near-wall *** study highlights the variability in accuracy among turbulence models,underlining the need for careful model selection based on specific prediction regions.

关键词： Salmon redd numerical simulation turbulence models volume of fluid(VOF)

Using Statistical Learning Algorithms in Regional Landslide Susceptibility Zonation with Limited Landslide Field Data

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Journal of Mountain Science 2015年第2期12卷 268-288页

作者： WANG Yi-ting SEIJMONSBERGEN Arie Christoffel BOUTEN Willem CHEN Qing-tao State Key Laboratory of Remote Sensing Science School of Geography Beijing Normal University National Marine Data & Information Service institute for biodiversity and ecosystem dynamics University of Amsterdam institute of Remote Sensing and GIS Chengdu University of Technology

Regional Landslide Susceptibility Zonation(LSZ) is always challenged by the available amount of field data, especially in southwestern China where large mountainous areas and limited field information coincide. Statistical learning algorithms are believed to be superior to traditional statistical algorithms for their data adaptability. The aim of the paper is to evaluate how statistical learning algorithms perform on regional LSZ with limited field data. The focus is on three statistical learning algorithms, Logistic Regression(LR), Artificial Neural Networks(ANN) and Support Vector Machine(SVM). Hanzhong city, a landslide prone area in southwestern China is taken as a study case. Nine environmental factors are selected as inputs. The accuracies of the resulting LSZ maps are evaluated through landslide density analysis(LDA), receiver operating characteristic(ROC) curves and Kappa index statistics. The dependence of the algorithm on the size of field samples is examined by varying the sizes of the training set. The SVM has proven to be the most accurate and the most stable algorithm at small training set sizes and on all known landslide sizes. The accuracy of SVM shows a steadilyincreasing trend and reaches a high level at a small size of the training set, while accuracies of LR and ANN algorithms show distinct fluctuations. The geomorphological interpretations confirm the strength of SVM on all landslide sizes. Our results show that the strengths of SVM in generalization capability and model robustness make it an appropriate and efficient tool for regional LSZ with limited landslide field samples.

关键词： Landslide Susceptibility Zonation(LSZ) Logistic Regression(LR) Artificial Neural Network(ANN) Support Vector Machine(SVM) Regional scale Southwest China

Herbivore performance and plant defense after sequential attacks by inducing and suppressing herbivores

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Insect Science 2019年第1期26卷 108-118页

作者： Elisa Faria de Oliveira Angelo Pallini Arne Janssen Department of Entomology Federal University of VicosaVicosaMGBrazil Department of Entomology Federal University of Lavras LavrasMGBrazil Section Population Biology Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam Amsterdamthe Netherlands

It is well known that herbivore-induced plant defenses alter host plant quality and can affect the behavior and performance of later arriving *** of sequential attacks by herbivores that either suppress or induce plant defenses are less well *** sequentially infested leaves of tomato plants with a strain of the phytophagous spider mite Tetranychus urticae that induces plant defenses and the closely related Tetranychus evansi, which suppresses plant *** quality was quantified through oviposifion of both spider mite species and by measuring proteinase inhibitor activity using plant material that had been sequentially attacked by both herbivore ***-mite oviposifion data show that *** could suppress an earlier induction of plant defenses by ***,and *** could induce defenses in plants previously attacked by *** in 1 *** attacks by the second species did not result in further changes in *** inhibitor activity levels showed that *** suppressed the high activity levels induced by *** to constitutive levels in 1 day,and further suppressed activity to levels similar to those in plants attacked by *** *** by *** induced proteinase inhibitor activity in plants previously attacked by ***,eventually to similar levels as induced by *** ***,plant quality and plant defenses were significantly affected by sequential attacks and the order of attack does not affect subsequent performance,but does affect proteinase inhibitor activity *** on our results,we discuss the evolution of suppression of plant defenses.

关键词： plant defense plant-herbivore interactions plant quality sequential attack Tetranychus evansi Tetranychus urticae

Environmental drivers of phytoplankton crops and taxonomic composition in northeastern Antarctic Peninsula adjacent sea area

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Acta Oceanologica Sinica 2022年第1期41卷 99-117页

作者： Yubin Feng Dong Li Jun Zhao Zhengbing Han Jianming Pan Gaojing Fan Haisheng Zhang Ji Hu Haifeng Zhang Jiaqi Wu Qiuhong Zhu Key Laboratory of Marine ecosystem dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

The ecosystem of the sea region adjacent to the Antarctic Peninsula is undergoing remarkable physical and biological changes, in the context of global warming. However, understanding of the dynamics of phytoplankton taxonomic composition in this marginal ice zone remains unclear. In this study, seawater samples collected from 36 stations in the northeastern Antarctic Peninsula were analyzed for nutrients and phytoplankton *** with CHEMTAX analysis, remote sensing data, and physicochemical measurements, we investigated the relationships between phytoplankton crops, taxonomic composition, and marine environmental *** chlorophyll a(Chl a) concentrations(200 m) varied from 8.9 mg/m^(2)to 64.2 mg/m^(2), with an average of(23.2±12.0) mg/m^(2)and higher phytoplankton biomass concentrated in the coastal region of South Orkney Island and South Shetland Island. Diatoms were the dominant functional group(63%±21%). Higher proportions of diatoms were associated with higher Chl a(r=0.40, p0.35, p<0.01), and lower MWC(r=-0.20, p<0.01). In comparison, the total contribution from green flagellates(4%±5%), cryptophyta(1%±3%), dinoflagellates(1%±4%), and cyanobacteria(1% ± 5%) was only 6%. In offshore regions with well-mixed water, less varied taxonomic composition and lower crops with a higher proportion of nanophytoplankton were observed. In contrast, significantly decreasing crops below the mixed layer depth was observed in

关键词： Antarctic Peninsula phytoplankton crops phytoplankton taxonomic composition pigment light intensity mixed layer depth