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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 dripline is a line on the ground at a cave entrance formed by drips from the rock above. useful in cave survey to define the beginning of the cave [25].?

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

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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 leaf (Keyword) returned 18 results for the whole karstbase:
Showing 1 to 15 of 18
Caves of Vakuta, Trobriand Islands, Papua, 1969, Ollier C. D. , Holdsworth D. K

In a previous paper (1968a) we described caves of Kiriwina, the largest of the Trobriand Islands, a group of coral islands situated 100 miles off the north-east coast of Papua. This paper records caves of Vakuta, a smaller island south of Kiriwina. Vakuta is shaped like a boomerang (Figure 1) and is separated from the southern tip of Kiriwina by Kasilamaka Passage, about half a mile wide. The area of Vakuta Island is approximately 11 square miles. The island contains three villages, the most important being Vakuta Village which has a Methodist (now United Church) Mission. A track links Vakuta Village to Kasilamaka Passage which can be crossed by native canoe; the track continues on Kiriwina to Losuia, 40 miles north. Vakuta Island has a population of about 500. The Vakutans are of the same mixed Melanesian-Polynesian stock as the people of Kiriwina. Woodcarving is not practised to the same extent as in Kiriwina and the quality is generally low. However, some canoes have particularly well decorated prows. The influence of the Mission is very evident in the dress of the Vakutans and in the village, old cast-off clothing, often quite dirty, is the rule. In the fields the women wear grass and fibre skirts though the men were not seen to wear a pubic leaf as usual in Kiriwina, but shorts. Papuan Airlines operate a weekly flight between Port Moresby and Losuia, the Administration Centre, using Skyvan aircraft. Weekend tourist charter flights in DC-3 aircraft arrive frequently, but irregularly, from Port Moresby and occasionally from Lae and Rabual. The authors visited Vakuta Island in December, 1968. Guides were recruited locally and we were fortunate to be assisted by Mr. Gilbert Heers, the only European resident of the island, who speaks fluent Kiriwini which made communication with our guides relatively easy. With his help, we were able to obtain accounts of the legends and traditions associated with the caves on the island. We have also had valuable discussions about Vakuta and the customs and legends of the Trobriand Islands with Mr. Lepani Watson, M.H.A., who was born on Vakuta, and Mr. John Kasaipwalova, a Trobriand Islander now studying at the University of Queensland. We are most grateful for the assistance of these people. Although the most accurate map of the Trobriands is an Admiralty chart, the authors used an old U.S. Army map which was based on a pre-war Government survey. The caves were roughly surveyed using 100 ft tape, prismatic compass and abney level. The village rest-house became the social centre of the village during our stay. We had no difficulty in finding food. A surprising variety of foods such as yams, sweet potato, eggs, pineapples, soursop, tomatoes and fresh coconut appeared and payment was accepted eagerly in stick tobacco and newspaper. Payment in cash was rarely appreciated, though it will become more useful now that a trade store has been established by the Village Co-operative. To avoid repetitive explanations of features in the accounts of individual caves, various general topics will be discussed first.

Caves of Kitava and Tuma, Trobriand Islands, 1971, Ollier C. D. , Holdsworth D. K. , Heers G.

The Trobriand group of coral islands is situated a hundred miles off the north-east coast of Papua and north of the D 'Entr'ecasteaux Islands. In previous papers we have described caves on Kiriwina (the main island), Vakuta and Kitava (see References). We now describe caves of Kaileuna and Tuma (see Figures l and 2). In August 1970, we spent one week of intensive search for caves on these two islands, making our headquarters in the copra store in the village of Kadawaga. Kaileuna island is six miles long and almost four miles wide, and supports a population of 1,079 (1969 Census). It is separated from the large island of Kiriwina by a channel two miles wide between Mamamada Point and Boll Point, though the main village of Kadawaga on the west coast of Kaileuna is 18 miles from Losuia and 14 miles from Kaibola. The island is generally swampy in the centre with a rim of uplifted coral around the edge. We were assured that the correct name of the island is Laileula, but since Kaileuna is used on all previous maps it is retained here. However, we prefer Kadawaga to the Kudawaga or Kaduwaga that appear on some maps. The inhabitants are of mixed Melanesian-Polynesian Stock, who are almost totally self-supporting, being in the main farmers and fishermen. The yam (taitu) constitutes the staple crop and the harvest is still gathered in with ceremonies unchanged for centuries. There is great competition among families for the quantity and quality of the crop, which is displayed firstly in garden arbours (kalimonio), later in the village outside the houses; traditionally styled yam huts (bwaima) are then constructed to display the harvest until the next season. The transfer of yams from the garden to the village is occasion for a long procession of gatherers to parade through the village blowing conch shells and chanting traditional airs (sawili) to attract the attention of villagers to the harvesting party, After storage of the harvest, a period of dancing and feasting (milamala) continues for a month or more, Traditional clothing is the rule, Women and girls wear fibre skirts (doba), most of the men, especially the older ones, wear a pubic leaf (vivia) made from the sepal of the betel nut palm flower (Areca catechu Linn.). Tuma, the northernmost of the main islands in the Trobriand group, is six miles long and less than a mile wide. It is a low ridge of coral with swamps in the centre and along much of the western side. The island has been uninhabited since 1963 when the last few residents abandoned it and moved to Kiriwina, but it is still visited from time to time by other islanders who collect copra and fish. Tuma is believed by all Trobriand Islanders to be inhabited now by the spirits of the dead. It is also generally believed that Tuma is the original home of the TrobIiand ancestors; these ancestors are also said to have emerged at Labai Cave on Kiriwina Island, and from many other places of emergence or 'bwala". Lack of consistency in the legends does not appear to concern the Trobrianders very much. The cave maps in this paper are sketches based mainly on estimated dimensions, with a few actual measurements and compass bearings. Bwabwatu was surveyed more accurately, using a 100 ft steel reinforced tape and prismatic compass throughout.

Distribution and Habitat Diversity of Subterranean Amphipods in the Rocky Mountains of Colorado, U.S.A., 1981, Holsinger John R. , Ward James W.
Subterranean amphipods have been collected from 35 locations on the eastern and western slopes of the Continental Divide in Colorado. All belong to the exclusively subterranean genus Stygobromus. Five species have been identified, two of which are undescribed. Specimens have been collected from (a) the hyporheic zone of rivers, (b) interrupted streams, (c) springs, and (d) seeps at elevations from 1597-2134 m a.s.l. Stygobromus occurs in several habitat types in interrupted drainage basins including sources, seeps, and isolated pools containing leaf detritus. All habitats contained waters which were cool to cold with dissolved oxygen values ranging from 4.3 ppm to fully saturated. Most waters exhibited soft or medium hardness, although one spring containing an undescribed species of Stygobromus had very hard waters (203 ppm bound CO2) and was mildly saline (913 mg/l TDS). There is evidence that the subterranean amphipods are phreatobites which, only under special conditions, establish relatively permanent populations in epigean habitats. Although little is known regarding ecology, zoogeography, or even taxonomy of the subterranean fauna of this region, stygobromid amphipods from the Cordilleran of western North America are apparently represented by fewer well differentiated species per unit area than their congeners from the geobiologicably older Appalachian region of eastern North America where numerous species are found in caves.

The cricket fauna of Chiapanecan caves (Mexico): systematics, phylogeny and the evolution of troglobitic life (Orthoptera, Grylloidea, Phalangopsidae, Luzarinae), 1993, Desuttergrandcolas Laure
The present study deals with the cavernicolous Grylloidea of Chiapas. It details the composition of this fauna, which belongs exclusively to the Phalangopsid group Amphiacustae, and considers its troglobitic evolution in the methodological framework of Comparative Biology. This method consists in analysing the evolution of biological features in reference to phylogeny, using character state optimization. The material studied comes mostly from Italian biospeological expeditions, but also from the authors work in Mexico, from North American biospeological expeditions achieved in Central America and the West Indies, and from the collections of the Academy of Natural Sciences of Philadelphia, the Museum National d'Histoire naturelle de Paris and the University of Michigan Museum of Zoology. I first present a systematic and phylogenetic analysis of Amphiacustae. Six new genera are defined and the genus Amphiacusta Saussure, 1874 is clearly delimited; twenty-three of the twenty six species considered in the paper are new and described. A key for genera and species groups is given. Phylogenetic relationships among genera are established using cladistics (implicit enumeration of Hennig 86 program). The evolution of troglobitic Amphiacustae is then analyzed. Available data on the biology of Amphiacust genera are presented and compared with what is known on other Phalangopsidae. Three biological attributes are moreover defined (troglobitic versus non troglobitic; cavernicolous versus non cavernicolous; leaf litter foraging versus leaf litter not foraging). The mapping of the attributes upon our cladogram has shown that Amphiacustae evolved twice toward cave life and that their ancestral habitat could be characterized by cavernicolous habits and leaf litter foraging. The results are discussed in reference to theories on troglobitic taxa evolution, and to the exaptation concept of Gould & Vrba (1982). This leads to three main conclusions: 1/ Amphiacust adaptation to caves could be the result of a tentative to exploit karstic resources in Central America; 2/ An epigean dispersion by cave living species can be hypothesized; 3/ For Grylloidea, having cavernicolous habits at ground level appears to be exaptative to troglobitic life.

Dry Chinquapin oak (Quercus macrocarpa) and American elm (Ulmus americana) leaves were placed in four microcosms fed by groundwater springs to monitor changes in dry mass, ash-free dry mass, and microbial activity over a 35-day period. Oxygen microelectrodes were used to measure microbial activity and to estimate millimeter-scale heterogeneity in that activity. Oak leaves lost mass more slowly than elm leaves. Generally, there was a decrease in total dry weight over the first 14 days, after which total dry weight began to increase. However, there were consistent decreases in ash-free dry mass over the entire incubation period, suggesting that the material remaining after initial leaf decomposition trapped inorganic particles. Microbial activity was higher on elm leaves than on oak leaves, with peak activity occurring at 6 and 27 days, respectively. The level of oxygen saturation on the bottom surface of an elm leaf ranged between 0 and 75% within a 30-mm2 area. This spatial heterogeneity in O2 saturation disappeared when the water velocity increased from 0 to 6 cm s-1. Our results suggest that as leaves enter the groundwater, they decompose and provide substrate for microorganisms. The rate of decomposition depends on leaf type, small-scale variations in microbial activity, water velocity, and the length of submersion time. During the initial stages of decomposition, anoxic microzones are formed that could potentially be important to the biogeochemistry of the otherwise oxic aquifer

The Rospo Mare oil field is located in the Adriatic Sea, 20 km off the Italian coast. The reservoir lies at a depth of 1300 m and consists of a paleokarst oi Oligocene to Miocene age which developed within Cretaceous limestones, now covered by 1200 m of Mio-Pliocene sequences. The oil column is about 140 m 8 high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed us to analyse the various solution features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including in particular paleovalleys as well as many pit-shaped sink holes. Detailed geophysical knowledge of that morphology helped to optimize the development of the field through horizontal drilling. Observations concerning the upper part of the reservoir were compared to a palaeokarst of the same age, outcropping widely onshore, in quarries located nearby. The Rospo Mare paleokarst is an integral part of the ante Miocene paleokarst assemblages of the periphery of the Mediterranean which were formed in tropical conditions. Only the fractures enhanced by meteoric water during the formation of the karat are important for reservoir connectivity. During the formation of the karst there were several phases of dissolution and infilling which modified the geometry of the open fissures and only these fractures play an important role in the reservoir drainage. Vertically we can distinguish three very different zones from top to bottom: at the top the epikarst (0-35 m) in a zone of extension. All the fractures have been enlarged by dissolution but the amount of infilling by clay is substantial. The clays are derived either from alteration of the karat fabric or by deposition during the Miocene transgression; the percolation zone (15-45 m) is characterized by its network of large fractures vertically enlarged by dissolution which corresponds to the relict absorption zones in the paleokarst. These fractures, which usually have a pluridecametric spacing, connect the epi-karst with the former sub-horizontal river system. This zone has been intersected by the horizontal wells during the field development. In this zone there are local, horizontal barriers oi impermeable clay which can block vertical transmissibility. In these low permeability zones the vertical fractures have not been enlarged due to dissolution hence the horizontal barrier; the zone of underground rivers (35-70 m) is characterized by numerous horizontal galleries which housed the subterranean ground water circulation. When these fissures are plurimetric in extent this can lead to gallery collapse with the associated fill by rock fall breccia. This can partly block the river system but always leaves a higher zone of free circulation with high permeabilities of several hundreds of Darcys. These galleries form along the natural fracture system relative to the paleohydraulic gradient which in some cases has been preserved. The zone below permanent ground water level with no circulation of fluids is characterized by dissolution limited to non-connected vugs. Very locally these fissures can be enlarged by tectonic fractures which are non-connected and unimportant for reservoir drainage. Laterally, only the uppermost zone can be resolved by seismic imaging linked with horizontal well data (the wells are located at the top of the percolation zone). The Rospo Mare reservoir shows three distinct horizontal zones: a relict paleokarst plateau with a high index of open connected fractures, (area around the A and B platforms); a zone bordering the plateau (to the north-east of the plateau zone) very karstified but intensely infilled by cap rock shales (Miocene - Oligocene age); a zone of intensely disturbed and irregular karst paleotopography which has been totally infilled by shales. The performance of the production wells is dependent on their position with respect to the three zones noted above and their distance from local irregularities in the karst paleotopography (dolines, paleovalleys)

Uplift rate relative to base-levels of a salt diapir (Dead Sea Basin, Israel) as indicated by cave levels, 1996, Frumkin A,
Rapid downcutting rates in the extremely soluble salt of the Sedom diapir, Dead Sea basin, Israel, allow cave channels to become rapidly graded with respect to base level. Diapir uplift leaves the older passages high and dry above present base level. Dating these passages by 14C allows us to estimate diapir uplift rates, taking into account previous Dead Sea levels. Maximum mean Holocene uplift rates are 6-7 mm a-1 along the eastern fault of Mount Sedom

The nutritional status of healthy and declining stands of Banksia integrifolia on the Yanakie Isthmus, Victoria, 1997, Bennett Lt, Attiwill Pm,
Banksia integrifolia L.f. has been in decline an calcareous sands of the Yanakie Isthmus, southern Victoria, since early 1980. Early studies indicated that the decline is associated with a particular soil condition possibly a nutritional imbalance involving Fe. However, in foliage samples collected from the three main soil types of the Isthmus, declining trees had similar concentrations of Fe but lower concentrations of Ca than healthy trees. Comparisons were made of seasonal variation in concentrations of macro- and micro-nutrients in foliage and litterfall from healthy trees (to minimise secondary changes associated with decline) within healthy and declining sites on the same soil type. On average, litterfall and the nutrient content of litterfall was greatest within the canopy area of B. integrifolia of the healthy stand. Banksias of the healthy stand also had greater concentrations of N, P, K and Na in fully-expanded leaves, resorbed greater proportions of phloem-mobile nutrients from senescent leaves and accumulated more Ca in senescent leaves. However, there was no evidence of nutritional imbalance in healthy trees within declining stands. It is argued that the lower foliar Ca in declining trees on three soil types and lower nutritional status of healthy trees within declining stands were due to lower productivity and lower water use and were therefore a result or an indication of decline rather than a cause

Les stalagmites : archives environnementales et climatiques haute rsolution, prsentation des protocoles dtudes et premiers rsultats sur des splothmes du Vercors, 1999, Perrette, Yves
Since the late 80's, the detailed study of speleothem has deve_loped from the crossing of two main approachs; one comes from the ques_tions of speleologists confronted with magnificent cave scenery, the other comes from citizen questions about climatic and environmental changes. The aim of this paper is to show the diversity and the relevance of the data collected by such studies on stalagmitic samples from the Vercors -France. The knowledge of the chemical processes of the H20 - CaCO3 - C02 system in the perspective of the karst infiltration leads to ques_tions about the role of the "supstrat". This word has been used to describe the "roofrock" rather than the bedrock. So, to better unders_tand the different modes of drainage in karst, a global hydrologic study of the Choranche cave vadose zone has been realised, e.g. seepage water rates have been monitoring. These recent studies allow us to model the structural and functional hydrologic network of such a well developed karst system. Actually we demonstrated the hierar_chisation of the drainage and the relation between a transmissive system and a capacitive one. They have been used to propose a graphical typology leading to a better appreciation of the various environmental interests of speleothems. Understanding the processes of speleothem environmental and climatic archiving, needs to know the processes of calcite crystal growth. They are briefly presented through some usual fabrics like columnar, palissadic or dendritic ones and through the optical relation between macroscopic colours and crys_talline porosity. It is the evolution of these crystalline features, which creates the laminae. To explain what are laminae, the diffe_rent type of emission by a solid after a laser irradiation are shown. It justifies the choice of two kinds of laminae measurement i.e. reflectance and fluorescence. Then, results of spectroscopic studies which show a covariation between Mn2+ concentration, the maximum intensity wave length of fluorescence spectra and the reflec_tance trend, allow us to consider reflectance measurement as a water excess proxy. This experimental approach is confirmed by the infra annual laminae. The hydrological interest of "visible" laminae (i.e. reflectance one) is increased by the fluorescence "invisible" lami_nae. In fact, the presence of a wide diversity of organic molecule in the calcite lead us to consider the fluorescence lamina as a temporal proxy controlled by the annual leaf fall and biopedological degradation. To measure these two proxies, an original experimental set has been developed in collaboration with the PhLAM laboratory (Lille, France). Particularly, this experimental set up permits to realise simultaneously a reflectance and a fluorescence image. The data collected are processed and are analysed in the frequency domain. All these data allow us to extract different proxies from speleothems. These proxies have been studied for some Vercors samples. We present the global environmental and climatic data archiving of the post_wurmian (isotopic stage 1) warming. At a higher resolution, the Vercors climate forcing is shown through the spectral analysis of the reflectance of a well laminated sample. The solar (T=22y) and atmospheric (NAO, T=17y) forcings are clearly distinguished. The climate analysis of this sample is limited by an anthropic mask. We show the similarity of the crystal facies evolution of two samples located around the Alps but far from more than 100 km. We would like to interpret this changes as an archiving of the post Little Ice Age warming but here too, Man interfere with climate to induce environmental changes. We show an example of the possibility for distinguishing climate from anthropic changes in environmental evolutions. The wealth of data of the speleothem allows us to appreciate the environ_ment stability of the Vercors which is confirmed in the spectral analysis of the growth rates of a Gouffre Berger sample. The diversity of the data collected in speleothems is directly linked to the diversity of the way of archiving in a karst system. It is why only a global approach seems to be relevant for answering environmental hydrological or morphological karst questions.

Simulating time-varying cave flow and water levels using the Storm Water Management Model, 2002, Campbell Cw, Sullivan Sm,
The Storm Water Management Model (SWMM) is an Environmental Protection Agency code used to estimate runoff through storm water drainage systems that include channels, pipes, and manholes with storage. SWMM was applied to simulate flow and water level changes with time for a part of Stephens Gap Cave in Jackson County, Alabama. The goal of the simulation was to estimate losses from a surface stream to the cave. The cave has three entrances that can remove water from the surface stream. These entrances connect through several passages to an 8-m (27-ft) high waterfall in a dome room. After a storm, the walls of this dome room had leaves on the wall as high as 4.6 m (15 ft) above the floor. The model showed that the height of the leaves did not represent a water level that could have occurred following any recent storm.Campbell, Livingston and Garza in 1997 developed the CLG model to estimate losses from karst surface streams. This model treats losses as pipe flow from a reservoir and gives the loss flow rate as ~h0.5 where h is the depth of flow in the surface stream. Losses to Stephens Gap Cave calculated with SWMM varied as h1.8. This depth dependence is more characteristic of flow over a weir than of pipe flow.The SWMM-calculated losses to Stephens Gap Cave showed no hysteresis, that is, the rising and falling limbs of the stage-discharge plot followed the same curve. Loss curves with significant hysteresis are difficult to simulate with simple models such as CLG or a weir flow model. However, an SWMM model of a simple hypothetical cave demonstrated that storage in Stephens Gap Cave is far below that required to cause hysteresis. Losses from many karst surface streams can probably be adequately estimated with a calibrated weir flow model. The utility of SWMM for analyzing cave flows was established. SWMM produced stable solutions with very low continuity errors for this cave

Les travertins de Saint-Antonin : squence gobotanique et climato-anthropique holocne (Bouches-du-Rhne, France), 2003, Guendon Jeanlouis, Ali Adam A. , Roiron Paul, Terral Jeanfrdric, Danna Andr, Diazdelolmo Fernando, Baenaescudero Rafael
Travertine deposit of St-Antonin (Bouches-du-Rhne, France): lithostratigraphy, palaeobotany and Holocene palaeoenvironments - Travertines are carbonate deposits formed generally during temperate climatic periods. The travertine of Saint-Antonin was formed during the Holocene in accordance with this model. They usually present a succession of travertinous units and detrital sedimentary levels containing, respectively, leaf impressions and charcoal; snail shells and archaeological material have also been preserved, essentially in detritial levels. Two kinds of plant remains (leaf imprints and charred wood) have been sampled and analysed, allowing the reconstruction of vegetation dynamics based on a well-defined sedimentary sequence. Our results were compared with those of previous malacalogical, archaeological studies and climatic changes. The Preboreal and Boreal sequence, characterised by travertine unites with detritial deposits, is dominated by a riverside vegetation (Populus alba, Salix sp., Phragmites communis) associated with some pubescent oak growing in the plateau. After this first period, detritial levels and hygrophilous species decrease. Correlatively travertinous facies and leaf impressions of mesophilous forest species increase (Quercus pubescent, Acer monspessulanum). They suggest the existence of homeostatic conditions, such as regular river flow, dense vegetation and few disturbances during deposition. The Middle Atlantic period shows optimal travertinisation and maintenance of forest environment. But this period is characterised by the beginning of the Quercus pubescens regression and the dominance of Acer monspessulanum. From the Atlantic to the first part of Subboreal, important detrital sedimentary levels disturb the deposition of carbonate. They contain reworked archaeological material dating to the Neolithic. Vegetation seems to have been profoundly affected by intensive human exploitation. This process has broken up the forested area into different plant communities and favoured the dominance of heliophilous and thermophilous species (Pinus halepensis, Rubus ulmifolius and Juniperus sp.).

Current issues and uncertainties in the measurement and modelling of air-vegetation exchange and within-plant processing of POPs, 2004, Barber Jl, Thomas Go, Kerstiens G, Jones Kc,
Air-vegetation exchange of POPs is an important process controlling the entry of POPs into terrestrial food chains, and may also have a significant effect on the global movement of these compounds. Many factors affect the air-vegetation transfer including: the physicochemical properties of the compounds of interest; environmental factors such as temperature, wind speed, humidity and light conditions; and plant characteristics such as functional type, leaf surface area, cuticular structure, and leaf longevity. The purpose of this review is to quantify the effects these differences might have on air/plant exchange of POPs, and to point out the major gaps in the knowledge of this subject that require further research. Uptake mechanisms are complicated, with the role of each factor in controlling partitioning, fate and behaviour process still not fully understood. Consequently, current models of air-vegetation exchange do not incorporate variability in these factors, with the exception of temperature. These models instead rely on using average values for a number of environmental factors (e.g. plant lipid content, surface area), ignoring the large variations in these values. The available models suggest that boundary layer conductance is of key importance in the uptake of POPs, although large uncertainties in the cuticular pathway prevents confirmation of this with any degree of certainty, and experimental data seems to show plant-side resistance to be important. Models are usually based on the assumption that POP uptake occurs through the lipophilic cuticle which covers aerial surfaces of plants. However, some authors have recently attached greater importance to the stomatal route of entry into the leaf for gas phase compounds. There is a need for greater mechanistic understanding of air-plant exchange and the 'scaling' of factors affecting it. The review also suggests a number of key variables that researchers should measure in their experiments to allow comparisons to be made between studies in order to improve our understanding of what causes any differences in measured data between sites. (C) 2003 Elsevier Ltd. All rights reserved

Hierarchical analysis of switchgrass morphology, 2005, Boe A, Casler Md,
Switchgrass (Panicum virgatum L.) has potential as a biomass crop in North America. Our objective was to determine effects of cultivar and location on morphological traits that influence biomass in switchgrass. Six cultivars with origins from 37 degrees N, 88 degrees W (Cave-In-Rock and Shawnee) to 46 degrees N, 100 degrees W (Dacotah) were evaluated in 1-yr-old swards at Bristol and South Shore, SD; in 3-yr-old swards at Brookings, SD, and Arlington, WI; and in 15-yr-old swards at Pierre, SD, for biomass; tillers m(-2); reproductive tiller proportions by count and weight, weight tiller(-1); phytomers tiller(-1); leaf, stem, and inflorescence components of tiller weight; and sheath and stem components of phytomer weight. Biomass production was related to region of cultivar origin [e.g., Shawnee produced two times more than Dacotah (6.2 Mg ha(-1))]. Tiller density was highest for Dacotah (1090 tillers m(-2)) and lowest for Cave-In-Rock (520 tillers m(-2)). Reproductive tiller fractions by count were plastic and higher at Arlington (0.81) than Brookings (0.08). Weights per reproductive tiller ranged from 0.7 g (Dacotah) to 3.4 g (Cave-In-Rock). Phytomers per tiller was not plastic (5.2 for Dacotah to 7.4 for Cave-In-Rock). Internode weight exhibited a basipetal increase and was highly plastic. Cultivars responded similarly to location effects on tillers m(-2), weight tiller', and biomass production. Cultivar differences for biomass production were attributed to variation at tiller (phytomers tiller(-1)) and phytomer (weight phytomer(-1)) levels

Land use change and soil nutrient transformations in the Los Haitises region of the Dominican Republic, 2005, Templer P. H. , Groffman P. M. , Flecker A. S. , Power A. G. ,
We characterized soil cation, carbon (C) and nitrogen (N) transformations within a variety of land use types in the karst region of the northeastern Dominican Republic. We examined a range of soil pools and fluxes during the wet and dry seasons in undisturbed forest, regenerating forest and active agricultural sites within and directly adjacent to Los Haitises National Park. Soil moisture, soil organic matter (SOM), soil cations, leaf litter C and pH were significantly greater in regenerating forest sites than agricultural sites, while bulk density was greater in active agricultural sites. Potential denitrification, microbial biomass C and N, and microbial respiration g(-1) dry soil were significantly greater in the regenerating forest sites than in the active agricultural sites. However, net mineralization, net nitrification, microbial biomass C, and microbial respiration were all significantly greater in the agricultural sites on g(-1) SOM basis. These results suggest that land use is indirectly affecting microbial activity and C storage through its effect on SOM quality and quantity. While agriculture can significantly decrease soil fertility, it appears that the trend can begin to rapidly reverse with the abandonment of agriculture and the subsequent regeneration of forest. The regenerating forest soils were taken out of agricultural use only 5-7 years before our study and already have soil properties and processes similar to an undisturbed old forest site. Compared to undisturbed mogote forest sites, regenerating sites had smaller amounts of SOM and microbial biomass N, as well as lower rates of microbial respiration, mineralization and nitrification g(-1) SOM. Initial recovery of soil pools and processes appeared to be rapid, but additional research must be done to address the long-term rate of recovery in these forest stands. (C) 2004, Elsevier Ltd. All rights reserved

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.

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