The effects of a bio-treatment on limestone (here tuffeau) is measured over a large number of dryingimbibition cycles. A model based on a space-dependent permeability coefficient is proposed. It leads to a non-linear diffusion model which accounts for the deviation from the standard Washburn model. Keyword: Limestone, bio-mineralization, water transfer, imbibition, non-linear diffusion

Editorial Natural geologic environments in China affect human health in a variety of ways through interactions between geochemical, hydro-logic, and biologic processes and human activities. Numerous national-scale cases serve as examples, including correlations between the distribution of Keshan and Kaschin-Beck diseases (both thought to be associated with nutritional deficiencies) and the nort...

Three new hypogean species of the Iberian genus Roncocreagris Mahnert, 1974 are described from mainland Portugal: R. borgesi sp. nov. and R. gepesi sp. nov. from caves in the Sicó massif, and R. occidentalis sp. nov. from caves in the Montejunto and Cesaredas karst plateau. This brings to nine the number of known hypogean species of the mostly Iberian genus Roncocreagris: five from Portugal and...

The aim of this study was to analyze yields, biological efficiency, earliness (expressed as days to first harvest), and precociousness and establish models for the mushroom growing according to these parameters. The experiment followed a double factorial design with four sources of calcium (calcitic limestone, calcitic limestone + gypsum, dolomitic limestone and dolomitic limestone + gypsum) an...

Five Angus heifers (285 kg) with duodenal and ileal cannulas were used to study the effects of feeding mineral acid neutralizers on digesta and fecal pH, intestinal acid flow, DM, starch and CP digestion and amino acid absorption in cattle fed a high-concentrate diet (7.5 kg/d). The experimental design was a 5 x 5 latin square. Treatments included control diet alone or control diet with the add...

In caves, microorganisms (algae, bacteria, archaea, fungi, protoza, and viruses) are major producers and consumers of organic matter and contribute to the formation of several types of minerals. However, with the notable exception of sulfide-based ecosystems, little is known about community composition, their specific adaptations to the subterranean ecosystem, their biogeographical distribution...

BACKGROUND The endemic and threatened troglobites (organisms restricted to caves) Charinus eleonorae (Amblypygi) and Iandumoema uai (Opiliones), both from Olhos d'Água cave, located at Peruaçu Caves National Park (southeast Brazil), have their distribution expanded for a new locality inside of the National Park (Lapa do Cipó cave), extending their distribution at least in 9.5km(2). NEW INFORM...

One unresolved issue in geomicrobiology is the involvement of microbial activity in the formation of secondary mineral deposits, or speleothems, in caves. Although there is extensive literature demonstrating the importance of bacteria in the precipitation of calcite in noncave environments, the role that these organisms play within caves remains unclear. Evidence in support of microbial involve...

Silurian outcrops, not previously recorded from central Texas, have been identified from the Llano uplift, where they occur in collapse structures within the Lower Ordovician Honeycut Formation of the Ellenburger Group. The formation is a pinkish-gray granular limestone, contains fossils of probable Wenlock age, and is named the Starcke Limestone.