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Artificial illumination in caves visited by tourists (“show caves”) gives rise to growth of photosynthetic biofilms, termed “lampenflora.” Besides being unsightly, these biofilms can damage speleothems, and thus finding a safe and effective means of controlling lampenflora is an important consideration in cave management. A variety of different physical and chemical means of biofilm mitigation have been proposed and tested. Here we tested benzalkonium chloride (BAC), a quaternary ammonium cationic detergent commonly used in pharmaceuticals and cosmetics, and germicidal UV light (UV-C) for lampenflora control. Algae and cyanobacteria derived from Carlsbad Cavern, USA, were cultivated in the lab and inoculated onto smooth calcium carbonate (CaCO3) tiles and incubated under fluorescent lighting to simulate lampenflora; these were then treated with BAC or UV-C in various concentrations and intensities, respectively. A 1–10% BAC solution prevented biofilm growth, and repeated treatments with a 1% solution bleached preformed photosynthetic pigments. Germicidal UV-C (≥ 3200 mJ cm−2) also bleached preformed biofilms. BAC may be especially useful for bleaching thick localized growths, since high concentrations are required and toxicity to non-toxic organisms could be an issue; whereas UV-C could more easily be applied to broader areas, e.g., the tens of square meter areas in the immediate vicinity of the lamps at Carlsbad Cavern and other show caves.

Fluorescent dyes are commonly used as hydrologic tracers in a variety of surface and subsurface environments, including karst aquifers and caves, but the fragile nature of karstic groundwater ecosystems suggests a cautious approach to selecting dyes. This study tested the effects of four fluorescent dye tracers (uranine, eosin, pyranine, sulforhodamine B) on microorganisms from Fort Stanton Cave, New Mexico, United States. Toxicity of the dyes was tested on bacteria isolated from the cave and on a sediment sample collected adjacent to Snowy River in Fort Stanton Cave. The isolates showed minimal inhibition by the four dyes in an agar diffusions assay. Minimum inhibitory concentrations calculated from liquid culture assays of one isolate were 35 g/L for uranine, 3.5 g/L for eosin, 0.1 g/L for pyranine, and 10 mg/L for sulforhodamine B. A

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Karstregionen beinhalten eine Vielzahl natürlicher Ressourcen, wie Süßwasser und Biodiversität, sowie zahlreiche kulturelle und historische Ressourcen. Die Welt-Karstaquifer-Karte (WOKAM) ist die erste detaillierte und vollständige globale Datenbasis über die Verbreitung von verkarstungsfähigen Gesteinen (Carbonate und Evaporite), welche potentielle Karstaquifere darstellen. Diese Studie präsentiert eine statistische Auswertung von WOKAM, mit dem Fokus auf Karst in Carbonatgesteinen, und adressiert vier wesentliche Aspekte: (i) globales Vorkommen und geografische Verteilung von Karst; (ii) Karst in verschiedenen topografischen Settings und in Küstengebieten; (iii) Karst in verschiedenen Klimazonen; und (iv) Bevölkerung in Karstgebieten. Die Analyse ergibt, dass 15,2 % der globalen, eisfreien Kontinentalfläche durch Carbonatgesteine charakterisiert sind. Der höchste prozentuale Anteil tritt in Europa auf (21,8 %); die größte absolute Fläche in Asien (8,35 Mio. km²). Weltweit treten 31,1 % aller anstehenden Carbonatgesteine in Ebenen auf, 28,1 % im Hügelland und 40,8 % in Gebirgen; 151,400 km oder 15,7 % der globalen marinen Küstenlinie wird von Carbonatgesteinen geprägt. Etwa 34,2 % aller Carbonatgesteine kommen im ariden Klima vor, gefolgt von 28,2 % in kalten und 15,9 % in gemäßigten Klimaten, während nur 13,1 % bzw. 8,6 % im tropischen bzw. polaren Klima anzutreffen sind. Global leben etwa 1,18 Milliarden Menschen (16,5 % der Weltbevölkerung) in Karstgebieten. Die höchste absolute Anzahl wurde in Asien ermittelt (661,7 Mio.), während die höchsten prozentualen Anteile in Europa (25,3 %) und Nordamerika (23,5 %) auftreten. Diese Ergebnisse zeigen die globale Bedeutung von Karst und dienen als Basis für weitere Forschung und internationale Wassermanagement-Strategien.

Karst aquifers contribute substantially to freshwater supplies in many regions of the world, but are vulnerable to contamination and difficult to manage because of their unique hydrogeological characteristics. Many karst systems are hydraulically connected over wide areas and require transboundary exploration, protection and management. In order to obtain a better global overview of karst aquifers, to create a basis for sustainable international water-resources management, and to increase the awareness in the public and among decision makers, the World Karst Aquifer Mapping (WOKAM) project was established. The goal is to create a world map and database of karst aquifers, as a further development of earlier maps. This paper presents the basic concepts and the detailed mapping procedure, using France as an example to illustrate the step-by-step workflow, which includes generalization, differentiation of continuous and discontinuous carbonate and evaporite rock areas, and the identification of non-exposed karst aquifers. The map also shows selected caves and karst springs, which are collected in an associated global database. The draft karst aquifer map of Europe shows that 21.6% of the European land surface is characterized by the presence of (continuous or discontinuous) carbonate rocks; about 13.8% of the land surface is carbonate rock outcrop.

Ksiromero occupies an area of 107 km2 in the northeast section of the Prefecture of Aitoloakarnania in western Greece. Its karst is developed primarily on beds of 10–200 m thick Triassic carbonate breccia conglomerates which underlie 70 % of the region. Other karstified units overly 200–300 m thick sequences of upper Triassic to early Jurassic limestones and dolomites and an underlying 150 m thick Triassic gypsum deposit. Major karst features include sinkholes and poljes that capture all surface water. Open caves and conduits are rare due to in-fill by residual terra rossa soils. “Ksiromero” is Greek for “dry place.” While in one of the wetter regions of Greece, with a mean annual precipitation of 962–1,040 mm and a mean evapotranspiration rate of 47 %, no perennial springs are known, surface water is rare, and accessible groundwater is minimal. Some shallow wells in the breccia conglomerate serve as small, local water supplies. Geochemical analyses of water samples from two wells show significant differences due to aquifer type (limestone versus terra rossa) but groundwater is suitable at least for irrigation and livestock and probably human consumption. Generally, domestically used water is supplied to Ksiromero from a neighboring region. Water for agriculture is stored in more than 75 reservoirs, some of which are natural sinkholes but most are excavated in terra rossa soils of poljes and large sinkholes. Shallow groundwater occurs in some of these reservoirs, as well as seasonally captured storm water, but much is pumped in from the adjacent region or from nearby wells. This system is adequate for the area’s modest water needs, but not for potential increased demand. Most land use is farming and pasture, and limited to the relatively flat floors of sinkholes and poljes. The absence of sanitary landfills and other agricultural contaminants potentially threaten groundwater quality, but the impacts are not presently quantifiable due to insufficient aquifer characterization.

Within semi-arid landscapes, karst areas are among the most productive in terms of water supply—largely because of the high rates of groundwater recharge compared with those of other semi-arid areas. Recharge rates in karst regions may be affected by the type of vegetation cover. Understanding the interactions between recharge and vegetation is important at many levels, but the complex nature of karst hydrology makes this endeavour challenging. This paper presents the results of a set of hillslope-scale rainfall simulation experiments conducted within a juniper–oak woodland and over a shallow karst cave that was instrumented for drip-rate monitoring. The variables measured during these experiments include the amounts and timing of cave recharge, surface runoff, stemflow, and throughfall. The findings of this study provide insights into the importance of canopy interception during runoff-producing events, the nature and relative magnitude of rapid recharge, and the interplay between recharge and surface runoff. Key findings of the study were (1) for simulated rainstorms of around 50 mm, between 0 and 23% of the water applied was intercepted (depending on cloud conditions), and 4–9% of the water reaching the ground surface came from stemflow (which was highest under the wettest conditions); (2) surface runoff accounted for approximately 3% of the water applied; and (3) recharge accounted for between 8 and 17% of the water applied and typically reached its maximum level within 20 min of rainfall cessation, declining rapidly thereafter. Copyright © 2009 John Wiley & Sons, Ltd.

A new mineral association composed of metatyuyamunite, celestite, opal and several minor crystalline phases has been identified in the Caverns of Sonora (Texas). The minerals were identified by means of X-ray diffractometry and optical and scanning electron microscopy. The main component of this association is metatyuyamunite, a uranyl vanadate mineral that appears as aggregates of sub-millimeter platy-like crystals that are often covered by botryoidal opal coatings. The orthorhombic unit cell of the Sonora metatyuyamunite had parameters a = 10.418, b = 8.508, and c = 17.173 A. Opal and celestite formed either directly over the yellow crust or along the cracks that traverse the limy mud on which metatyuyamunite was precipitated. The secondary uranium-vanadium minerals described herein were precipitated in the final stages of cave development.

In their efforts to protect regional groundwater supplies, governmental agencies are increasingly requiring studies of karst areas and their features. In areas where tracer tests or geophysics are not required, funded, or otherwise feasible, geomorphological methods remain as the primary tool for assessing karst. This study proposes a geomorphologically-based environmental impact assessment strategy for karst areas. While it is supported with results from a study of the karstic Edwards Aquifer recharge zone on the Camp Bullis Military Training Installation, TX, USA, it is based on the study of several karst areas and is generalized to accommodate and be fine-tuned for regional variations. Biological and other resource issues can also be assessed with this strategy. The assessment identifies environmentally sensitive features and areas, as is often required to meet regulatory directives. In karst areas with relatively small features, excavation is a key tool for accurate assessment. Although the results of this study will help to better manage karst areas, proper management must be done on a regional scale. The highly permeable nature of karst precludes adequate management solely on a feature-by-feature basis. Studies on the relationship of water quality to impervious cover show adverse environmental impacts significantly increase when impervious cover exceeds 15% of a surface watershed. The Camp Bullis study finds similar impacts in its groundwater drainage basin, supporting the argument of 15% impervious cover as a regionally effective means of also protecting karst aquifers when coupled with protection of critical areas identified by field surveys.

Introduction Government Canyon State Natural Area (GCSNA) is located within the northwest limits of San Antonio, Texas, USA. It is a karst area that was planned for urban development but purchased by a partnership of three governmental agencies and two non-profit organizations. This arrangement was unprecedented for the state of Texas and established the first of many actions that would make GCSNA a model of how to best purchase, research, develop, and manage a property for natural resource protection. This paper first outlines the natural and cultural resources of GCSNA, then uses its history as a model example by which multi-disciplinary research and cooperation of several partners can be used for effective karst resource management. Abstract Government Canyon State Natural Area (GCSNA) is located on the northwest edge of San Antonio, Texas, USA. Ninety percent of the 47.04 km2 property is located on the recharge zone of the karstic Edwards (Balcones Fault Zone) Aquifer. Urban development is encroaching onto the Edwards Aquifer karst and threatening groundwater quality and karst ecosystems. GCSNA has served as a model for karst management by

This chapter defines “national cave and karst research institute” as “an organization created to conduct, facilitate, and promote state-of-the-art cave and karst research, education, and management, and recognized nationally as a leading authority on such matters.” Twelve institutes from nine countries were identified; one institute is inactive. Most were created as governmental programs, often affiliated with a university, while the rest are non-profit, for-profit, or hybrid (combining at least two of the other three organizational structures). Each structure inherently lends itself to different levels of authority and engagement in cave and karst management issues. The role of national institutes in cave and karst management is a subset within each of the institutes’ basic purposes: Research, education and publication, independent advice and arbitration, data archiving, funding generation and granting, and collaboration facilitation. To date, most institutes have focused their efforts on theoretical research, archiving of data, and production of publications, and not on applied management issues. While activity in karst management is generally increasing, it is conducted mostly by the younger institutes and includes greater education efforts, funding, and advisory service. Because of widely different circumstances in each institute’s origin, administration, age, and national laws and culture, generalizations are difficult but some trends are proposed for the next few decades: •Karst institutes will increasingly develop hybrid organizational structures. •Karst institutes will predominantly focus on karst management issues. •Technical and public education will become prominent karst institute programs. •Karst institutes will increase their support of digital open access karst libraries and the creation of virtual karst research tools. •Karst institute funding will increase through diversification of services and perceived increase in value. •Karst institutes will formally link for greater effectiveness and better use of limited resources.

Recent investigations at a number of sites in the highlands of Guatemala have uncovered the existence of man-made, man-modified, and pseudo-karst caves. The caves were excavated from volcanic or volcanically derived Tertiary and Quaternary age rocks, with construction methods varying according to rock hardness, and the pre-existence of pseudo-karst caves and springs. Some of these caves are of considerable length and are associated with site centers or places of particular ritual importance. Their continued role as local and even regional foci of ritual activity suggests that these features were created to lend a sense of sanctity to the sites where they are located. The analysis of these features within the context of site architecture deomonstrates the central symbolic importance of caves within Maya cultural geography.

Much of the Maya civilization in pre-Columbian Meso-America was established on karst terrain that included parts of what are now Belize, Guatemala, northern Honduras and southern Mexico. By definition, little surface water exists in karst, so for the Maya to flourish on that terrain they had to effectively and efficiently utilize all their water resources. Access to groundwater was by means of springs and caves. Maya life, urban and rural, lay and elite, religious and secular was often a function of groundwater exploitation and surface water development. The Maya's use of groundwater was predominantly to supplement enhanced surface water supplies and was used more often in semiarid zones than in humid zones. The pattern of Maya settlements, especially in the semiarid zones, occurred in areas with greater access to the groundwater. Maya groundwater retrieval methods were primitive, inefficient, labor intensive, and uninnovative, as compared to their other technologic achievements. Groundwater contamination, from human effluent, could have resulted in widespread disease and contributed to the Maya's downfall.

Few studies have quantified recharge into caves from overlying fractures. In areas such as San Antonio, Texas that rely primarily on karst (limestone) aquifers for potable water, the quantity and quality of recharge through these features could have significant implications for evaluating and managing groundwater. Vegetation cover also has the ability to influence recharge characteristics, when the vegetation is located directly above caves and inside the surface water and groundwater drainage basins. These studies in the Edwards Aquifer recharge zone north of San Antonio, evaluate the effects of woody cover on the water budget of two shallow caves. Use of large-scale rainfall simulation equipment above the caves allows re-creation of rainfall events where amount, rate, and duration of previously occurring events are simulated. One cave’s footprint is instrumented with throughfall collectors and rain gauges to estimate canopy interception. Four trees are instrumented with stemflow collectors and transpiration measurement devices that record data, later scaled up to account for stemflow over the entire plot. Inside both caves, drip collectors constructed of PVC pipe and clear polyurethane plastic sheeting collect and route water to tipping buckets that digitally record recharge volumes onto a datalogger. In order to evaluate recharge rates and responses typical of the landscape, the collectors capture dripwater falling from the caves’ ceiling, which travels into the caves through fractures, and not as focused recharge through sinkholes and cave entrances. Continuous automatic recording of recharge allows us to evaluate the effects of simulated and natural rainfall events on recharge rates, volumes, and durations. Preliminary analysis of natural and simulated data has shown that fractures can move large volumes of recharge quickly into the caves.

Variations in the lithology of carbonate units can result in different morphologies in caves and conduits and in their hydrologic roles in karst aquifers. Examples are provided from the San Antonio area of central Texas. Solutional sinkholes are common in the Person Formation but less common in the Kainer Formation where small, solutionally enlarged fractures tend to open to large and deep caves. Members of the Person usually form broad rooms and passages along bedding planes and often contain considerable breakdown due to medium to thin limestone beds that frequently contain incompetent interbedded clay. Groundwater and conduits are occasionally perched for short distances on the Region Dense Member, with the longest reported horizontal extent estimated at 500 m before dropping into the Kainer Formation. The Kainer’s Kirschberg Member produces few caves and karst features in San Antonio, but facies changes make it highly cavernous near Austin 150 km to the north. Conversely, the Kainer’s Dolomitic Member near San Antonio forms some of the deepest pits in the state yet is essentially non-cavernous in north Austin. The Basal Nodular Member and the upper member of the Glen Rose Formation form some of the largest chambers and passages in the study area, yet are effectively non-cavernous elsewhere. However, even where the Glen Rose produces large caves, few significant karst features form in its outcrop. These and other characteristics can be derived from detailed analyses of cave and karst feature databases and can be used as a predictive tool to improve the efficacy of environmental impact assessments. Examples include the prediction of groundwater drainage area size and location, estimating the volume of flush water needed for successful tracer tests, aquifer conceptual model development, and improving the design and interpretation of geophysical studies.

Materials with high toughness often have fibrous microstructures or are made as fibrous composites. One possible route to new infrared-transmitting materials is through sulfide analogs of those silicates known to have fibrous structures. SiS2 itself occurs as fibrous crystals isostructural with the rare oxide polymorph, silica-W. However, it is extremely reactive with oxygen and water. An investigation is underway of compound formation in the systems CaS-SiS2, MgS-SiS2, and NaS-Al2S3-SiS2 to search for such fibrous silicate analogs as CaSiS3 (thiowollastonite), MgSiS3 (thioenstatite), CaMgSi2S6 (thiodiopside), and NaA1Si2S6 (thiojadeite). A second phase of the investigation is to construct crystal chemical analogs with less chemical reactivity: e.g. Ge for Si, rare earths for Al, and the larger alkaline earths (Ba, Sr) for the more reactive smaller ones (Ca, Mg).