MWH Global

Enviroscan Ukrainian Institute of Speleology and Karstology

Community news

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That virgin flow is flow unaffected by artificial diversions, impoundments, or channels [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for pollen (Keyword) returned 39 results for the whole karstbase:
Showing 16 to 30 of 39
Speleothem evidence for Holocene fluctuations of the prairie-forest ecotone, north-central USA, 1999, Denniston Rf, Gonzalez La, Baker Rg, Asmerom Y, Reagan Mk, Edwards Rl, Alexander Ec,
Carbon and oxygen isotopic trends from seven Midwestern speleothems record significant offsets in the timing of middle-Holocene vegetation change. Interactions of dry Pacific and moist Gulf of Mexico air masses maintained a sharp moisture gradient across Iowa, Minnesota, and Wisconsin such that the arrival of prairie was offset by 2000 years between caves and pollen sites located only 50 km apart. Oxygen isotopes shift concomitantly with carbon in most cases, although these changes are believed to represent increased evaporative enrichment of 18O prior to infiltration during the prairie period

A Holocene millennial-scale climatic cycle from a speleothem in Nahal Qanah Cave, Israel, 1999, Frumkin A, Carmi I, Gopher A, Ford Dc, Schwarcz Hp, Tsuk T,
Nahal Qanah Cave, located in the east Mediterranean region, has been inhabited by humans during several periods of the Holocene. These well-dated cultures are used here to establish the age of a speleothem growing over archaeological remains. d18O and d13C from a stalagmite through the last 6000 years display a 1000-2000-year cycle. Depleted d18O and d13C value correlate well with high Dead Sea levels and increased arboreal pollen, suggesting common climatic control affecting the entire region

Holocene millenial-scale climatic cycle from Nahal Qanah Cave speleothem, Israel, 1999, Frumkin, A. , Carmi, I. , Gopher, A. , Tsuk, T. , Ford, D. C. And Schwarcz, H. P.
Nahal Qanah Cave, located in the east-Mediterranean region, has been inhabited by humans during several periods of the Holocene. These well-dated cultures are used here to establish the age of a speleothem growing over archaeological remains. d18O and d13C of a stalagmite through the last 6000 years display a 1-2 thousand years cycle. Depleted d18O and d13C values correlate well with high Dead Sea levels and increased arboreal pollen, suggesting common climatic control affecting the entire region.

Paleoclimatology: Reconstructing the Climates of the Quaternary, 1999, Bradley R. S.

Raymond S. Bradley provides his readers with a comprehensive and up-to-date review of all of the important methods used in paleoclimatic reconstruction, dating and paleoclimate modeling. Two comprehensive chapters on dating methods provide the foundation for all paleoclimatic studies and are followed by up-to-date coverage of ice core research, continental geological and biological records, pollen analysis, radiocarbon dating, tree rings and historical records. New methods using alkenones in marine sediments and coral studies are also described. Paleoclimatology, Second Edition, is an essential textbook for advanced undergraduate and postgraduate students studying climatology, paleoclimatology and paleooceanography worldwide, as well as a valuable reference for lecturers and researchers, appealing to archaeologists and scientists interested in environmental change.* Contains two up-to-date chapters on dating methods* Consists of the latest coverage of ice core research, marine sediment and coral studies, continental geological and biological records, pollen analysis, tree rings, and historical records* Describes the newest methods using alkenones in marine sediments and long continental pollen records* Addresses all important methods used in paleoclimatic reconstruction* Includes an extensive chapter on the use of models in paleoclimatology* Extensive and up-to-date bibliography* Illustrated with numerous comprehensive figure captions

Palynological evidence for Mesozoic karst at Piltown, Co. Kilkenny, 2000, Higgs K. T. , Jones G. L. ,
Exploration drilling by Pasminco Australia Ltd. in 1993 at Piltown near Carrick-on-Suir. encountered brown. yellow and fawn clays of the Piltown Clay Formation (new name) lying on and in Carboniferous limestone. Palynological analysis of these clays indicates that they are late Jurassic to early Cretaceous in age. The palynomorphs are well preserved but not abundant. They consist mostly of terrestrially derived spores and pollen grains, though the rare occurrence of dinoflagellate cysts indicates a weak marine influence in some of the sediments. The presence of these Mesozoic sediments within karstified limestone implies an active karat system before and/or during late Jurassic-early Cretaceous times in south County Kilkenny

Symposium Abstract: Sources of pollen in stalactite drip water in two caves in South West France, 2001, Genty D. , Diot Mf. , O'yl W.

Sources of pollen in stalactite drip water in two caves in southwest France, 2001, Genty D. , Diot Mf. , O'yl Willford

The sedimentary records in Mediterranean rockshelters and caves: Archives of environmental change, 2001, Woodward J. C. , Goldberg P. ,
It is important to develop rigorous methods and robust conceptual models for the interpretation of rockshelter and cave sediment records so that the cultural sequences they contain can be considered in their proper environmental context. Much of what we know about the prehistory of the Mediterranean region and adjacent areas has largely been pieced together from materials excavated from sedimentary sequences in these environments. The rockshelters and caves of the region form important environmental and sedimentary archives. Recent work has begun to consider if the remarkable climatic variability evident in the high resolution lacustrine and ice core records is manifest in the rockshelter and cave sediment records of the area, In this context, the two main characteristics of a rockshelter or cave site which control its usefulness as an archive of environmental change are the temporal resolution of the sedimentary record and the environmental sensitivity of the site. Many rockshelters and caves can be described as either Active Karst Settings (AKS) or Passive Karst Settings (PKS) and site type is an important influence on climatic sensitivity with a direct influence upon the usefulness of the sedimentary sequence as a proxy record of climate change. It is now clear that some sites may preserve detailed paleoclimatic records and the climatic signal may be represented by distinctive suites of micromorphological features, by variations in the input of allogenic sediment, or by fluctuations in the mineral magnetic properties of the fine sediment fraction. It can be argued that data derived from the analysis of bulk coarse-grained samples often lacks the stratigraphic resolution and environmental sensitivity that can be obtained from other approaches. The most favorable sites for detailed paleoclimatic reconstruction appear to be in active karst settings such as Theopetra Cave (Greece) and Pigeon Cave (Morocco) where micromorphological analyses offer insights into the stratigraphic record that are not otherwise obtainable. The temporal resolution of a site can only be established through a rigorous stratigraphic analysis and a comprehensive dating program. These are fundamental considerations in the study of rockshelter sediment records, especially when attempting to correlate between sites and draw comparisons with other proxy records of environmental change derived from sedimentary environments with rather different characteristics. Rockshelters and caves are part of a wider sediment system, and their investigation must be accompanied by detailed geomorphological, sedimentological, paleoecological, and geochronological studies of the off-site Quaternary record.

Cave surface pollen and the palynological potential of karstic cave sediments in palaeoecology, 2001, Navarro C. , Carrion J. S. , Munuera M. , Prieto A. R. ,
Palynological results are presented of surface cave sediments from six caves of southeastern Spain, which differ in location, morphology, size, orientation and number of entrances. The results address several issues of pollen taphonomy in a cave environment. Modern sediments from caves contain pollen assemblages that may reflect local and regional vegetation even better than those obtained in the exterior environment. Cave geometry is an important factor affecting the quality of pollen spectra registered inside the cavity. Generally, the highest concentrations of palynomorphs are observed in the cave entrance and in sediments associated to dry depositional conditions. Speleothems and wet carbonated sediments, and those obtained from wall and rear areas often contain altered pollen spectra. Biotically transported taxa can help to provide palaeoecological information. The depositional context is extremely complex and caution should be taken in palaeoecological reconstruction. Therefore, uniform rules for sampling strategy should not be applied to all cave sediments. (C) 2001 Published by Elsevier Science B.V

Eustatic sea-level and climate changes over the last 600 ka as derived from mollusc-based ESR-chronostratigraphy and pollen evidence in Northern Eurasia, 2002, Molodkov Anatoly N. , Bolikhovskaya Nataliya S. ,
We reconstruct and correlate palaeoclimatic events and deposits from shelf, glacial, periglacial, and extraglacial zones of northern Eurasia over the last 600,000 years. The chronostratigraphical correlation of identified palaeoenvironmental and sea-level events and corresponding horizons is based on electron spin resonance (ESR) analysis of subfossil mollusc skeletal remains from marine, freshwater and Acheulian-bearing cave-site deposits. Over 230 shell samples from more than 40 sites along the continental margin of Eurasian north, in the Black and Caspian sea basins and terrestrial shells from a Lower Palaeolithic cave-site in the Northern Caucasus were dated via ESR to produce a late Quaternary geochronology. The Pleistocene composite section of the loess-palaeosoil formation includes two reference sections--Likhvin and Arapovichi--from the centre of the East-European plain. The palyno-chronostratigraphic record is interpreted as the product of six warm-climate/high sea-level events including the current interglacial, and six glacial events. They are presented either as complete climatic rhythms of glacial and interglacial rank, or by considerable portions of climatic-phytocoenotic phases constituents of the rhythm. The full-interglacial conditions are centred at about 580, 400, 310, 220 and between 145-70 calendar ka. A broad correspondence between long palynological sequence, directly ESR-dated warm-climate-related events and other palaeoenvironmental records described in the literature has been noted for 11 upper oxygen isotope stages (11 to 1). The results obtained in this study exemplify the potential of integrated chrono-climatostratigraphic sequences in linking marine and terrestrial palaeoclimate records that may eventually span the whole Brunhes chron

Dosimetric and radiocarbon chronology of a pre-Wisconsinan mastodon fossil locality at East Milford, Nova Scotia, Canada, 2003, Godfreysmith D. I. , Grist A. M. , Stea R. R. ,
We report the final results of a multidisciplinary geochronological study of two subfossil mastodon remains and the sediments associated with them. from the East Milford, N.S. mastodon locality discovered in 1991. The mastodons, which were found in a karstic sinkhole system, are the latest and the most complete of several mastodon remains discovered in Nova Scotia, New Brunswick and Maine over the last 170 years. The unconsolidated sediments containing the adult specimen were dated using optical dating (IRSL); the mastodon dental enamel was dated using electron spin resonance (ESR); and bone collagen from both individuals plus associated wood were dated using radiocarbon (C-14) dating. Two samples of sediment adhering to the walls of the karstic cavity at the elevation corresponding to the location of the adult specimen yielded statistically indistinguishable IRSL ages of 127 13 (EMM1) and 143 16 ka (EMM2), with a weighted mean of 133 6 ka. This is consistent with pollen data which indicate an interglacial climate. On the basis of its stratigraphic position with respect to overlying till units, the locality is attributed to oxygen isotope stage 5. Three ESR dates on dental enamel (natural prompt, deproteinated prompt, and deproteinated delayed) yielded statistically indistinguishable ages whose weighted mean is 74.9 5.0 ka. This indicates consignment to the geologic record of the mastodon tooth during terminal oxygen isotope stage 5a, when the climatic cooling leading to the Wisconsinan glacial period had already begun. Fission-track analysis of the enamel and dentine cross sections showed minimal U uptake, resulting in no need for early, linear, or late uptake modelling. The direct ESR age indicates that the specimen either became mired in a cavity that was already at least partly infilled with older, probably waterlogged, sediments, or that the sediment's IRSL signal was not completely erased during deposition. The dosimetric ages are consistent with limiting radiocarbon ages on bone collagen (juvenile > 45,760 years BP; adult greater than or equal to 37,040 1730 BP) and wood (near the adult mastodon > 51,000 BP; organic-rich horizon above the karst surface > 50,000 BP). These results provide the first direct age on a mastodon fossil from Atlantic Canada, and the first numeric estimate to demonstrate that mammoths were present in this region during pre-Wisconsinan times, specifically during late oxygen isotope stage 5a. (C) 2003 Elsevier Science Ltd. All rights reserved

Fens in karst sinkholes - Archives for long lasting 'immission' chronologies, 2003, Hettwer K. , Deicke M. , Ruppert H. ,
Fens in karst sinkholes are excellent archives for the reconstruction of vegetation, land use and emission rates over millennia. The reasons are the usually good preservation of pollen, the high portion of low density organic material with very low background concentrations of heavy metals, and the circum-neutral pH-values in most of these mires preventing migration of heavy metals. Immissions of dust and of harmful elements can easily be correlated with changes in vegetation ('immission' is a synonym for the deposition or impact of pollutants from the atmosphere on a receptor surface). One 13 m core from a similar to5000 yr old karst sinkhole fen (Silberhohl, western margin of the Harz Mountains, central Germany) was investigated by geochemical analysis, pollen analysis and dated by C-14 and palynological data. The core consists of organic material with a few percent of CaCO3 precipitated from groundwater and a small amount of atmospheric detritus. As early as the Iron Age (first pre-Christian millennium), slight but significant enrichments of Pb, Zn, Cu and Cd are observed. After 400 AD stronger enrichments occurred culminating in the High Middle Ages (similar to1200-1300 AD). Maximum values are 1250 mug g(-1) Pb, 214 mug g(-1) Cu, 740 mug g(-1) Zn, and 3.8 mug g(-1) Cd. The enrichments are caused by emissions during smelting of sulfidic lead-zinc ores from the adjacent Hercynian deposits to extract Ag and Cu. Except for cadmium, these values were never exceeded in modern times. Since the Iron Age 23 g technogenic Pb, 5.3 g Cu, 27 g Zn and 0.2 g Cd have been deposited per square meter. Palynological investigations show a strong correlation between decreasing red beech pollens (Fagus sylvatica) and increasing demand on wood for smelting in the Middle Ages. Simultaneously, the pollen share of pioneer trees such as birch (Betula pubescens) and of cereal grains (e.g. Secale) increases. Since the beginning of the 14th century, the decline of agriculture and population is reflected in the decreasing contents of Secale and heavy metals in the fen deposits

Palaeoenvironments in semi-arid northeastern Brazil inferred from high precision mass spectrometric speleothem and travertine ages and the dynamics of South American rainforests, 2004, Auler A. S. , Wang X. , Edwards R. L. , Cheng H. , Cristalli P. S. , Smart P. L. , Richards D. A.

Understanding past environmental changes in tropical rainforests is extremely important in order to assess the response of such environments to present and future climatic changes and understand causes and the present patterns of biodiversity.
Earlier hypothesis on the origin of biodiversity have stressed the role of past climatic changes in promoting speciation. According to the “refuge hypothesis” (Haffer, 1982), dry periods could have led to forest fragmentation, isolating more humid forested zones (called refuges) within an environment largely dominated by savannas. The refuge hypothesis does not assign timescales for rainforest fragmentation, although recent studies have suggested that speciation could have occurred over timescales of millions of years (Knapp and Mallet, 2003). Although the focus of heavy criticism (Colinvaux, et a., 2000), the refuge hypothesis has generated a large amount of research. In general, pollen studies (Colinvaux, et a., 1996, Haberle and Maslin, 1999) tend to support a continuous forest cover throughout late Quaternary climatic shifts, although large variations in rainfall have also been demonstrated by other pollen and isotopic studies (van der Hammen and Absy, 1994; Maslin and Burns, 2000).
Amazon and Atlantic rainforests are the two major forested zones in South America. Amazon rainforest, the largest rainforest in the world, comprise a total original area of 4.1 million km2 and is renowned for hosting the large biodiversity in the world (30% of all the world’s known plant and animal species). Atlantic rainforest, also a biodiversity hotspot, occurs along the coast and has been subjected to heavy deforestation since European arrival. Nowadays only c. 7% of its original forested area of 1.3 million km2 remains. These two rainforests are separated by drought-prone semi-arid northeastern (NE) Brazil. Our study does not address the refuge hypothesis directly although it sheds new light on the dynamics of forest expansion in the past as well as indicates alternative ways of promoting speciation. It has long been hypothesized, due to botanical (Mori, 1989; Andrade-Lima, 1982) and faunistic (Costa, 2003) similarities, that the Amazon and Atlantic rainforests were once linked in the past. Although numerous connecting routes have been postulated (Bigarella, et al, 1975; Por, 1992; De Oliveira, et al, 1999), the timing of forest expansion and their possible recurrence have remained elusive.
The study area lies in the driest portion of NE Brazil “dry corridor”, close to the village of Laje dos Negros, northern state of Bahia. Mean annual precipitation is around 480 mm and potential evapotranspiration is in excess of 1,400 mm/year (Fig.1). Present vegetation comprises a low arbustive scrubland known locally as caatinga. The area contains a well-developed underground karst (Auler and Smart, 2003) with abundant secondary calcite precipitates, both underground (speleothems) and on the surface (travertines).

Depositional and post-depositional history of warm stage deposits at Knocknacran, Co. Monaghan, Ireland: implications for preservation of Irish last interglacial deposits, 2004, Vaughan A. P. M. , Dowling L. A. , Mitchell F. J. G. , Lauritzen S. E. , Mccabe A. M. , Coxon P. ,
Organic-rich deposits, uncovered during overburden removal from mantled gypsum karst at Knocknacran opencast gypsum mine, Co. Monaghan, are the best candidate to date for a last interglacial record in Ireland. The two till and organic-rich deposits (preserved at different quarry elevations) were emplaced on to a Tertiary dolerite surface during high-energy flood events and subsequently folded and faulted by movement towards sinkholes in underlying gypsum. Uranium-thorium disequilibrium dating suggests that the organic-rich deposits in the upper section were hydrologically isolated at ca. 41 ka and those in the lower section at ca. 86 ka. Interpretation of the pollen content, although tentative because of the depositional and post-depositional history of the material, suggests that the organic material originated in a warm stage possibly warmer than the post-Eemian interstadials. The unusual setting of preservation may indicate that in situ, last interglacial deposits have generally been removed by erosion in Ireland.

Environmental change across the Early-Middle Pleistocene transition: small mammalian evidence from the Trinchera Dolina cave, Atapuerca, Spain, 2005, Cuencabescos G, Rofes J, Garciapimienta J,
The sites of Atapuerca are well known for their hominin-bearing localities of Early to Middle Pleistocene age. Trinchera Dolina yields western Europe's oldest fossil hominin, the 850 ka Homo antecessor; and at Sima de los Huesos there occurs the best collection of the Middle Pleistocene hominin Homo heidelbergensis. However, small mammals (Rodentia, Insectivora, Chiroptera and Lagomorpha) represent the largest number of species and greatest fossil abundance in the deposits of the Atapuerca cave complex. The small mammals are grouped by habitat categories, but because the ecology of mammals is complex, we base our study on the evolution of these categories throughout the sequence. The assemblage distribution at the Trinchera Dolina site reflects landscape and environmental changes during the past million years. Shifts between woodland, open land and moorland are indicated by the relative abundance of species based on diagnostic elements such as first lower molars. These data are combined with the distribution of large mammals, pollen, sediments and geological context of the Trinchera Dolina site. From this interdisciplinary approach, we conclude that the first hominins from western Europe (Homo antecessor) lived during a warm, wet and wooded interval, probably corresponding to Marine Isotope Stages 21 to 19. The transition from Early to Middle Pleistocene at Atapuerca is characterized by palaeoenvironmental changes recorded between levels TD5-6 and TD8-10, respectively. The general opening of the landscape at the beginning of the Middle Pleistocene could have favoured the dispersal of hominins (Homo heidelbergensis) across western Europe

Results 16 to 30 of 39
You probably didn't submit anything to search for