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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 column is 1. a subsurface dripstone formation produced by the union of a stalactite and a stalagmite in a cave [20]. 2. a flowstone formation, generally cylindrical, formed by the union of a stalactite and stalagmite [10]. not to be confused with pillar. synonyms: (french.) colonne, pillier stalamitique; (german.) tropfstein-saule; (greek.) stalaktitike stele; (italian.) colonna (stalagmitica o stalattitica) (russian.) kolona; (spanish.) columna; (turkish.) sutun; (yugoslavian.) stup, steber, stolpic. see also pillar.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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;
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Your search for tree (Keyword) returned 49 results for the whole karstbase:
Showing 16 to 30 of 49
Uncalculated impacts of unsustainable aquifer yield including evidence of subsurface interbasin flow, 2000, Bacchus St,
Unsustainable withdrawals from regional aquifers have resulted in adverse impacts considerable distances from the point locations of supply wells. In one area of the southeastern (SE) Coastal Plain, conservative estimates for repair/replacement of some residential wells damaged or destroyed by unsustainable yield from the Floridan aquifer system exceeded $4 million. However, a comprehensive assessment of damage/economic loss to private property and public resources due to unsustainable yield from that regional karat aquifer has not been made. Uncalculated direct costs to home-owners from damage attributed to those withdrawals are associated with destruction of homes from increased sinkhole formation, devalued waterfront property, and removal of diseased and dead trees. Examples of other uncalculated economic burdens resulting from unsustainable aquifer yield in the SE Coastal Plain include: (1) irreversible damage to the aquifer matrix and concomitant increased potential for groundwater contamination, (2) large-scale wildfires with subsequent degradation of air quality, debilitation of transportation corridors, and destruction of timber, wildlife habitat and property, and (3) destruction of 'protected' natural areas. This paper provides a general background of the regional Floridan aquifer system's karst characteristics, examples of known impacts resulting from ground water mining in the SE Coastal Plain, and examples of additional damage that may be related to unsustainable yield from the Upper Floridan aquifer. Costs of these impacts have not been calculated and are not reflected in the price users pay for ground water. Evidence suggests that the classic watershed management approach must be revised in areas with mined regional karst aquifers to include impacts of induced recharge from the surficial aquifer, and subsurface interbasin flow. Likewise, associated impacts to surface water and interrelated systems must be calculated The true cost of groundwater mining to this and future generations should be determined using a multidisciplinary approach

Tree-mould caves in Slovakia., 2003, Gaal Ludovit
Four tube-shaped caves are described in this work, which origined in consequence of weathering the trees. Their length ranges from 5.8 to 17 m. All of them occur in neovolcanic rocks of Middle Slovakia, in epiclastic andesite conglomerates, breccias or in the tuffs. Some other caverns are close to the entrance of this caves, however they are inaccessible for a man. Thin rim of silicates (opal or chalcedony) occurs in some of them.

Dissolved organic carbon in precipitation, throughfall, stemflow, soil solution, and stream water at the Guandaushi subtropical forest in Taiwan, 2003, Liu C. P. , Sheu B. H. ,
The concentration and flux of dissolved organic carbon (DOC) were measured in precipitation, throughfall, stemflow, soil solution, and stream water for three types of subtropical forest stands, a Chinese fir (Cunninghamia lanceolata) plantation, a secondary hardwood, and a natural hardwood stand in Guandaushi forest in central Taiwan from January 1998 to December 1998. The mean DOC concentration in precipitation was 4.7 mg l(-1). However, in the rain passing through the tree canopies and barks as throughfall and stemflow, the mean concentrations were 7.0 and 30.8, 9.9 and 10.0, and 8.3 and 7.2 mg l(-1) in the Chinese fir plantation, the secondary hardwood, and the natural hardwood, respectively. Mean DOC concentrations in soil solution were lower in the Chinese fir plantation than both hardwoods, and decreased with depth of soil profiles. Stemflow DOC flux (132.4 kg ha(-1)) in the Chinese fir plantation was much higher than the other hardwood stands (15.3 and 6.7 kg ha(-1) in secondary and natural hardwood, respectively). The monthly variations of DOC concentrations were very similar in throughfall and stemflow at the three stands, showing an increase in the beginning of the growing season in April. No clear monthly variations in soil solution DOC concentrations (mean from 3.2 to 21.3 mg l(-1) in different stands and for different depths) were found in our study. DOC concentrations (mean 2.7 mg l(-1)) in the stream draining the watershed were higher in spring and in winter. (C) 2002 Elsevier Science B.V. All rights reserved

Cambial growth of Swietenia macrophylla King studied under controlled conditions by high resolution laser measurements, 2003, Dunisch O, Schulte M, Kruse K,
The kinetics of phloem and xylem formation of two-year-old plants of Swietenia macrophylla King (true mahogany) was studied in a model system along the shoot circumference (experiment 1) and along the shoot axis (experiment 2). The radius increment of the shoot was registered by high resolution laser measurements (accuracy: 2 mum) in a spatial resolution of 7.8 to 41.3 mum along the stem circumference and 1.5 mm along the stem axis. The temporal resolution of the measurements was 2 s in experiment 1 and 20 s in experiment 2. The radius increment of the shoot detected by the laser measurements was predominately due to the radial enlargement of the phloem and xylem derivatives. On the phloem side the reinitiation of radial cell enlargement after a cambial dormancy occurred first in sieve tubes with contact to ray parenchyma cells, while on the xylem side the radial cell enlargement of vessels and paratracheal parenchyma was induced almost simultaneously along the shoot circumference. In the phloem and xylem derivatives, which were formed first after the cambial reactivation, radial cell enlargement was induced almost simultaneously along the shoot axis. In more advanced phases of phloem and xylem formation, radial cell enlargement of phloem and xylem derivatives was induced shoot downwards with a rate of approximately 13 mm per min. The mean rate of radial cell enlargement of the phloem and xylem derivatives was 2.26 and 4.37 mum per min, respectively. These findings suggest that the kinetics of cambial growth of tropical tree species differ significantly from kinetics observed in trees from temperate regions. The laser measurements might provide a useful experimental approach for studies of cambial activity in situ

The application of Time-Lapse Microgravity for the Investigation and Monitoring of Subsidence at Northwich, Cheshire, 2003, Branston Mw, Styles P,
Peter Street is an area of terraced houses in Northwich suffering from subsidence, thought to be related to salt extraction in the 19th century. Microgravity and resistivity profiling have been used as non-invasive techniques to investigate the cause of this subsidence. Repeat (or time-lapse) microgravity has been used to assess the stability and evolution of the low-density areas. Time-lapse microgravity uses the characteristics of anomaly size and gradient to track the development of cavities as they propagate to the surface. It is possible to monitor the change in gravity with time and to model the increase in cavity volume and/or depth. A gravity low was found to be coincident with the area experiencing subsidence. Integratedmodelling techniques including Euler deconvolution, Cordell & Henderson inversion and GRAVMAG modelling have been used to investigate the depth and size of the body responsible for this anomaly. Resistivity imaging has been used to investigate the conductivity of the near surface and constrain the gravity models. Results from both techniques suggest that low density ground is now present at a depth of 3-4 m below the surface in the subsidence affected area. The use of time-lapse microgravity has shown that there has been an upwardmigration of a low-density zone at gravity anomaly C over the monitoring period

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

Der neue Stammbaum der alpinen Hhlenbren., 2004, Rabeder G. , Hofreiter M.
In the Upper Pleistocene the Alps were inhabited by at least three taxa of cave bear (group) which differ in their mitochondrial DNA as well as in metrical and morphological criteria. The possibilities of distinguishing these evolutionary lineages in the fossil record are described and discussed. Two high Alpine dwarf forms are described as possible subspecies of U. spelaeus (U. s.? ladinicus and U. s.? eremus), the third taxon is separated as an independent species (U. ingressus). By means of numerous diagrams an attempt is made to find metrical and morphological differences in the teeth and limb bones in order to distinguish the three Alpine taxa. A new phylogenetic tree is drawn. [Hhlenbren-Forschung in Europa, DNA-Untersuchungen]

Drinking water supply from karst water resources (The example of the Kras plateau, SW Slovenia), 2004, Ravbar Nataš, A

In the past the biggest economic problem on the Kras plateau used to be drinking water supply, which has also been one of the reasons for sparsely populated Kras plateau. Today the Water Supply Company provides drinking water to households and industry on the Kras plateau and the quantity is sufficient to supply the coastal region in the summer months as well. Water supply is founded on effective karst groundwater pumping near Klariči. Some water is captured from karst springs under Nanos Mountain as well. In water supply planning in future, numerous other local water resources linked to traditional ways of water supply need to be considered. Eventual rainwater usage for garden irrigation or car washing, for communal activity (street washing) or for the needs of farming and purified wastewater usage for industry (as technological water) is not excluded.


Der neue Stammbaum der alpinen Hhlenbren, 2004, Rabeder G. , Hofreiter M.
In the Upper Pleistocene the Alps were inhabited by at least three taxa of cave bear (group) which differ in their mitochondrial DNA as well as in metrical and morphological criteria. The possibilities of distinguishing these evolutionary lineages in the fossil record are described and discussed. Two high Alpine dwarf forms are described as possible subspecies of U. spelaeus (U. s.? ladinicus and U. s.? eremus), the third taxon is separated as an independent species (U. ingressus). By means of numerous diagrams an attempt is made to find metrical and morphological differences in the teeth and limb bones in order to distinguish the three Alpine taxa. A new phylogenetic tree is drawn.

Sediment storage and yield in an urbanized karst watershed, 2005, Hart Evan A. , Schurger Stephen G. ,
In karst watersheds, sinkholes and other drainage features control the temporal and spatial pattern of sediment storage across the landscape. However, studies dealing with sedimentation in karst watersheds are scarce and the sediment storage function of sinkholes and caves has not been investigated using a sediment budget approach. In this study, we use estimates of channel erosion, sinkhole sedimentation, and suspended sediment yield to examine changes in sediment storage in the 9 km2 Upper Pigeon Roost Creek fluviokarst watershed near Cookeville, TN. The study watershed has undergone urbanization over the last ~ 50 years, and sinkholes and caves in the area show signs of recent sedimentation (buried tree roots, buried cultural artifacts, etc.). While sinkholes are generally considered to be sediment sinks, sinkholes examined in this study are shown to cycle between periods of net sediment storage and net sediment loss. Using copyright dates on trash items buried in sinkhole deposits, we estimated the residence time of sinkhole-stored sediment to range from 6 to 10 years. However, other evidence indicates that some sinkholes may store sediment for several centuries. We propose that sediment storage within sinkholes is controlled by several factors including sinkhole drainage area, sinkhole morphology, and basin sediment yield. In addition, changes in sediment storage in karst watersheds are contingent upon random events such as sinkhole collapses. Annual sediment yield was estimated to be 111 Mg km- 2 year- 1 for the entire study watershed and ranged from 11 to 128 Mg km- 2 year- 1 for 3 sub-watersheds. Sediment eroded from the watershed, perhaps during historic settlement of the area, is stored within a large cave system underlying the city. However, the results of a partial sediment budget indicate that the cave is presently a net sediment source. Overall, the findings indicate that the sediment storage function of caves and sinkholes varies spatially and temporally, and that these changes need to be incorporated into sediment budgets for karst watersheds

Ecology and hydrology of a threatened groundwater-dependent ecosystem: the Jewel Cave karst system in Western Australia, PhD Thesis, 2005, Eberhard, S. M.

Groundwater is a significant component of the world’s water balance and accounts for >90 % of usable freshwater. Around the world groundwater is an important source of water for major cities, towns, industries, agriculture and forestry. Groundwater plays a role in the ecological processes and ‘health’ of many surface ecosystems, and is the critical habitat for subterranean aquatic animals (stygofauna). Over-abstraction or contamination of groundwater resources may imperil the survival of stygofauna and other groundwater-dependent ecosystems (GDEs). In two karst areas in Western Australia (Yanchep and Leeuwin-Naturaliste Ridge), rich stygofauna communities occur in cave waters containing submerged tree roots. These aquatic root mat communities were listed as critically endangered because of declining groundwater levels, presumably caused by lower rainfall, groundwater abstraction, and/or forest plantations. Investigation of the hydrology and ecology of the cave systems was considered essential for the conservation and recovery of these threatened ecological communities (TECs). This thesis investigated the hydrology and ecology of one of the TECs, located in the Jewel Cave karst system in the Leeuwin-Naturaliste Ridge. A multi-disciplinary approach was used to explore aspects pertinent to the hydrology and ecology of the groundwater system.
Thermoluminescence dating of the limestone suggested that development of the karst system dates from the Early Pleistocene and that caves have been available for colonisation by groundwater fauna since that time. Speleogenesis of the watertable maze caves occurred in a flank margin setting during earlier periods of wetter climate and/or elevated base levels. Field mapping and leveling were used to determine hydrologic relationships between caves and the boundaries of the karst aquifer. Monitoring of groundwater levels was undertaken to characterise the conditions of recharge, storage, flow and discharge. A hydrogeologic model of the karst system was developed.
The groundwater hydrograph for the last 50 years was reconstructed from old photographs and records whilst radiometric dating and leveling of stratigraphic horizons enabled reconstruction of a history of watertable fluctuations spanning the Holocene to Late Pleistocene. The watertable fluctuations over the previous 50 years did not exceed the range of fluctuations experienced in the Quaternary history, including a period 11,000 to 13,000 years ago when the watertable was lower than the present level.
The recent groundwater decline in Jewel Cave was not reflected in the annual rainfall trend, which was above average during the period (1976 to 1988) when the major drop in water levels occurred. Groundwater abstraction and tree plantations in nearby catchments have not contributed to the groundwater decline as previously suggested. The period of major watertable decline coincided with a substantial reduction in fire frequency within the karst catchment. The resultant increase in understorey vegetation and ground litter may have contributed to a reduction in groundwater recharge, through increased evapotranspiration and interception of rainfall. To better understand the relationships between rainfall, vegetation and fire and their effects on groundwater recharge, an experiment is proposed that involves a prescribed burn of the cave catchment with before-after monitoring of rainfall, leaf-area, ground litter, soil moisture, vadose infiltration and groundwater levels.
Molecular genetic techniques (allozyme electrophoresis and mitochondrial DNA) were used to assess the species and population boundaries of two genera and species of cave dwelling Amphipoda. Populations of both species were largely panmictic which was consistent with the hydrogeologic model. The molecular data supported the conclusion that both species of amphipod have survived lower watertable levels experienced in the caves during the Late Pleistocene. A mechanism for the colonization and isolation of populations in caves is proposed.
Multi Dimensional Scaling was used to investigate patterns in groundwater biodiversity including species diversity, species assemblages, habitat associations and biogeography. Faunal patterns were related to abiotic environmental parameters. Investigation of hydrochemistry and water quality characterized the ecological water requirements (EWR) of the TEC and established a baseline against which to evaluate potential impacts such as groundwater pollution.
The conservation status of the listed TEC was significantly improved by increasing the number of known occurrences and distribution range of the community (from 10 m2 to > 2 x 106 m2), and by showing that earlier perceived threatening processes (rainfall decline, groundwater pumping, tree plantations) were either ameliorated or inoperative within this catchment. The GDE in the Jewel Cave karst system may not have been endangered by the major phase of watertable decline experienced 1975-1987, or by the relatively stable level experienced up until 2000. However, if the present trend of declining rainfall in southwest Western Australia continues, and the cave watertable declines > 0.5 m below the present level, then the GDE may become more vulnerable to extinction.
The occurrence and distribution of aquatic root mat communities and related groundwater fauna in other karst catchments in the Leeuwin-Naturaliste Ridge is substantially greater than previously thought, however some of these are predicted to be threatened by groundwater pumping and pollution associated with increasing urban and rural developments. The taxonomy of most stygofauna taxa and the distribution of root mat communities is too poorly known to enable proper assessment of their conservation requirements. A regional-scale survey of stygofauna in southwest Western Australia is required to address this problem. In the interim, conservation actions for the listed TECs need to be focused at the most appropriate spatial scale, which is the karst drainage system and catchment area. Conservation of GDEs in Western Australia will benefit from understanding and integration with abiotic groundwater system processes, especially hydrogeologic and geomorphic processes.


Ecology and hydrology of a threatened groundwater-dependent ecosystem: the Jewel Cave karst system in Western Australia [abstract], 2006, Eberhard S. M.
This thesis investigates the hydrology and ecology of a threatened aquatic root mat community in the Jewel Cave karst system in the Leeuwin-Naturaliste Ridge, Western Australia. Development of the karst system dates from the Early Pleistocene and the caves have been available for colonisation by groundwater fauna since that time. Speleogenesis of the watertable maze caves occurred in a flank margin setting during earlier periods of wetter climate and/or elevated base levels. Watertable fluctuations over the last 50 years did not exceed the range experienced in the Quaternary history. The recent groundwater decline in Jewel Cave was not related to rainfall, nor groundwater abstraction nor nearby tree plantations. However, it did coincide with a reduction in fire frequency within the karst catchment. The resultant increase in understorey vegetation and ground litter may have reduced groundwater recharge through increased evapotranspiration and interception of rainfall. The populations of two genera and species of cave dwelling Amphipoda are largely panmictic. Both species have survived lower watertable levels during the Late Pleistocene. A mechanism for the colonization and isolation of populations in caves is proposed. Faunal patterns (including species diversity, species assemblages, habitat associations and biogeography) were related to abiotic environmental parameters. The ecological water requirements of the community were determined as a baseline for evaluation of impacts such as groundwater pollution. If rainfall continues to decline, and the cave watertable declines > 0.5 m below the present level, then the groundwater ecosystem may become more vulnerable to extinction. The taxonomy and distribution of root mat communities is poorly known and a regional-scale survey is required to properly assess their conservation requirements. Meanwhile, conservation actions for the communities need to be focused at the scale of the karst drainage system and catchment area.

Reversibility of forest conversion impacts on water budgets in tropical karst terrain, 2006, Chandler Dg,
A conceptual model of the control of tropical land use and vegetative cover on bedrock recharge is developed for highly permeable geologic substrates. A case study of water budgets is then developed from field data and simple modeling for upland sites with three different vegetative covers (cropland, intensively grazed pasture and forest regrowth) in Leyte, Philippines. Water budget model results show that annual precipitation is divided primarily between evapotranspiration and overland flow for the pasture, but apportioned more to evapotranspiration and inputs to bedrock storage for the crop and forest sites. Modeled evapotranspiration from the forest (1906 mm) was not sufficiently greater than that for either the crop (1661 mm) or pasture (1476 mm) sites to offset the greater overland flow from those sites. The differences in overland flow are related to depth profiles of soil bulk density, which decreased between crop and forest and increased between crop and pasture, and drainable porosity, which increased between crop and forest and decreased between crop and pasture. Dry season streamflow is assumed to be primarily base flow and dependent on wet season bedrock recharge, which was dramatically lower for the pasture (106 mm) than for the crop (1134 mm) or forest covers (1320 mm), for 2946 mm of rainfall. The results support the premise that for landscapes with adequate storage in bedrock fractures, forest regrowth can increase recharge to perched aquifers, and hence dry season baseflow, relative to cropping and that dramatic reductions in overland flow and increases in dry season baseflow may be achieved by reforestation of compacted pastures. (c) 2005 Elsevier B.V. All rights reserved

How much did climate force the Messinian salinity crisis? Quantified climatic conditions from pollen records in the Mediterranean region, 2006, Fauquette S, Suc Jp, Bertini A, Popescu Sm, Warny S, Bachiri Taoufiq N, Perez Villa Mj, Chikhi H, Feddi N, Subally D,
The latest Miocene (5.96 to 5.33[no-break space]Ma) is characterised by an outstanding event: the desiccation of the Mediterranean Sea (Messinian salinity crisis). It has been suggested that this was caused by a tectonic event, with no climatic change playing a role in desiccation. Quantifying the climate of the region during this period will help support or refute this hypothesis. An effective method for reconstructing the climate from Neogene pollen data is the 'Climatic Amplitude Method' based on the modern climatic requirements of plants to interpret fossil data. It has been conceived especially for periods devoid of modern vegetation analogue.Twenty Messinian to Lower Zanclean pollen sequences are now available in the peri-Mediterranean region. Most of them do not cover the whole Messinian interval, particularly those along the Mediterranean shorelines where sedimentation was interrupted during the sea's desiccation. In contrast, sedimentation was almost continuous in such areas as the Atlantic side of Morocco, along the Adriatic coast (including the Po Valley), and to a lesser extent the Black Sea. The Mediterranean sites nonetheless provide a reliable if not a discontinuous record of vegetation variability in time and space.A first examination of the pollen diagrams reveals a high regional variability controlled by local conditions, and throughout the interval a southward increase in herb pollen frequency in contrast to the tree pollen frequency. This indicates that open and probably dry environments existed in the southern Mediterranean region prior to, during and after the salinity crisis. Trees developed in areas close to mountains such as in the Po Valley, in Cerdanya and in the Black Sea region. Most variations observed in the pollen diagrams are constrained by fluctuations of Pinus pollen amounts, indicating eustatic variations. Climatic quantification from pollen data does not show obvious climatic changes due to the desiccation of the Mediterranean Sea, especially in the dry and warm southwestern Mediterranean area (Sicily, southern Spain and North Africa). At Maccarone, along the Adriatic Sea, a decrease in temperatures of the coldest month and, less importantly, a decrease in mean annual temperatures, corresponding to a drastic vegetation change, are reconstructed. These temperature variations are assumed to be controlled by regional environmental changes (massive arrival of waters in this basin) rather than to reflect cooling, because some authors link the second phase of evaporite deposition to a period of global warming. Some migrations of plants probably occurred as a response to Mediterranean desiccation. But the climatic contrast which has probably existed at that time between the central Mediterranean and the peripheral areas might be amplified.Climatic reconstruction from pollen data in the western Mediterranean area shows that climate is not the direct cause of the Mediterranean desiccation, as the Mediterranean region had experienced continuously high evaporation long before the crisis. Therefore the main factor leading to this event seems to be the successive closures of the Betic and Rifian corridors, isolating the Mediterranean Sea from the Atlantic Ocean

Applications of stalagmite laminae to paleoclimate reconstructions: Comparison with dendrochronology/climatology, 2006, Tan Ming, Baker Andy, Genty Dominique, Smith Claire, Esper Jan, Cai Binggui,
Laminated stalagmites, observed in either ultra-violet or visible light or recognized via trace elements, are now widely recognized as a common deposition form. Annually laminated stalagmites should be expected in caves which have an overlying climate that has a strong seasonality, similar climate zones to where trees grow with distinct annual rings. Continuous laminated stalagmite chronologies (up to several thousand years) should be expected where some mixing of stored water occurs. Such stalagmites can be used to reconstruct climate, particularly through variations in lamina width. Such climate records would be relatively damped by mixing of `event' water with `stored' groundwater, constraining the amount of high-frequency climate signals contained in the stalagmite, but relatively long continuous lamina sequences permit the preservation of low frequency, centennial scale, climate signals. This contrasts with numerous tree ring climate records, which are frequently limited in preserving multi-centennial trends, due to the necessary removal of age related noise from relatively short tree segments. Laminated stalagmites and tree rings should therefore to some degree provide complementary climate information. Appropriate methods for compiling stalagmite layer chronologies and climatologies are presented

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