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Clastic sedimentary rocks are generally considered non-karstifiable and thus less vulnerable to pathogen contamination than karst aquifers. However, dissolution phenomena have been observed in clastic carbonate conglomerates of the Subalpine Molasse zone of the northern Alps and other regions of Europe, indicating karstification and high vulnerability, which is currently not considered for source protection zoning. Therefore, a research program was established at the Hochgrat site (Austria/Germany), as a demonstration that karst-like characteristics, flow behavior and high vulnerability to microbial contamination are possible in this type of aquifer. The study included geomorphologic mapping, comparative multi-tracer tests with fluorescent dyes and bacteria-sized fluorescent microspheres, and analyses of fecal indicator bacteria (FIB) in spring waters during different seasons. Results demonstrate that (i) flow velocities in carbonate conglomerates are similar as in typical karst aquifers, often exceeding 100 m/h; (ii) microbial contaminants are rapidly transported towards springs; and (iii) the magnitude and seasonal pattern of FIB variability depends on the land use in the spring catchment and its altitude. Different ground water protection strategies than currently applied are consequently required in regions formed by karstified carbonatic clastic rocks, taking into account their high degree of heterogeneity and vulnerability.
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An ecological study of the microarthropod communities from Las Sardinas cave was undertaken. Four different biotopes were studied over the course of a year: bat guano, litter, soil under the chemoautotrophic bacteria colonies and as a control, plain soil without litter or guano. A total of 27,913 specimens of a total of 169 species were collected. Analysis of Variance (ANOVA) showed that there is a significant effect of biotope on the recorded density, and the post hoc Tukey’s test showed that guano is the most different biotope with the highest value of density recorded. The interaction between season and biotope variables was not significant. In the most extreme case, 99 percent of the microarthropods in soil under chemoautotrophic bacteria were mites, mainly in the family Histiostomidae.
Caves can be divided into three distinct regions - the twilight zone, the transitional zone and the troglic zone. The main physical characters of caves - light, air currents, temperature and humidity - are discussed in relation to their effect on cave fauna. Various classifications of cave animals are mentioned, and those of Schiner and Jeannel discussed in detail. The paucity of food in caves, and its effect on the animal population is considered. Mention is made of the loss of secondary sexual characters and seasonal periodicity of breeding among true troglobites. Cave animals have undergone many adaptations to their environment, the most interesting of these being blindness and loss of pigment. Hyper-development of tactile, gustatory, olfactory and auditory organs and general slenderness of body, are correlated with eye degeneration. Several theories on the origin of cave fauna are discussed, and the importance of isolation on the development of cave fauna considered.
Between July, 1960, and December, 1963, observations were made on the natural history of Rhinolophus megaphyllus Gray in north-eastern New South Wales. Typically the species occurs as small colonies in a wide variety of cave and mine roosts. It appears to be absent from available roosting sites at higher altitudes in this area. Seasonal changes in the sizes of testes and epididymides suggest that mating occurs in May and June. The single young are born at maternity colonies through November, and nursing lasts about eight weeks. Field weights do not reflect seasonal variation other than that associated with pregnancy. However, seasonal differences in daytime level of activity are noted and these correlate with behavioural changes apparently related to temperature selection. Changes in colony size are described for several roosts and three movements made by marked individuals are recorded. Males appear to be more sedentary than females. Considerable aggregation of females and their young at maternity colonies (size, 15 to 1,5000 individuals) characterises the spring and summer population.
The three cave systems are developed along the course of a seasonal stream that has been superposed on a range of Devonian Limestone in north-western Australia. The cave system furthest upstream has the greatest known development of cave passages in the region (more than 2,300 yards) and is controlled by two sets of vertical joints approximately at right angles to each other.
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.
After brief descriptions of the geomorphology of the Cooleman Plain karst and in particular of the Blue Waterholes, the methods adopted to analyse the functioning of these major risings are detailed. The discharge regime of Cave Creek below them is oceanic pluvial in type perturbed by drought and snow. There is much annual variation both in seasonal incidence and total amount, with catchment efficiency correspondingly variable. Suspended sediment concentration is even more erratic and monthly determinations are inadequate for calculating corrasional denudation rates. Mean concentrations of suspended solids are about 1/18th of solute load. Total dissolved salts have a strong inverse relationship with discharge, and mean values are high compared with those for other catchments in eastern Australia but none of these determinations are from limestone catchments. Sodium, potassium, and chlorine contents are low compared with the same catchments but silica is relatively high. The ratio of alkaline earths to alkalis indicate that Cave Creek carries carbonate waters and there is an inverse regression of the ratio on discharge. There is inverse correlation of total hardness on discharge likewise due to concentration of surface waters by evaporation in dry periods, together with reduced underground solution rate at times of large, rapid flow. The spring waters remain aggressive. Close regressions of hardness on specific conductivity now permit the latter to be determined in the place of the former. Much evidence converges to indicate that all the springs at the Blue Waterholes are fed from the same conduit. The intermittent flow which comes down the North Branch on the surface to the Blue Waterholes differs significantly in many characters from the spring waters. Rates of Ca + M carbonate equivalent removal vary directly with discharge since hardness varies much less than does water volume. These gross rates have to be adjusted for (a) atmospheric salts entering the karst directly, (b) peripheral solute inputs from the non-karst two-thirds of the catchment and (c) subjacent karst solution before they can be taken as a measure of exposed karst denudation. The methods for achieving this are set out. The total corrections amount to about one third of the total hardness, though the correction for subjacent karst on its own lies within the experimental error of the investigation. The residual rate of limestone removal from the exposed karst also shows a winter/spring high rate and a summer/autumn low rate but the seasonal incidence and annual total varied very much from year to year. In comparison with results from karsts in broadly similar climate, the seasonal rhythm conforms and so does the high proportion (78%) of the solution taking place at or close to the surface. This reduces the importance of the impounded condition of this small karst but supports the use of karst denudation rate as a measure of surface lowering. Cave passage solution may however be more important in impounded karst than its absolute contribution might suggest, by promoting rapid development of underground circulation. The mean value of limestone removal is low for the climatic type and this is probably due to high evapotranspirational loss as well as to the process of eliminating atmospheric, peripheral non-karst and subjacent karst contributions. The difficulties of applying modern solution removal rate to the historical geomorphology of this karst are made evident; at the same time even crude extrapolations are shown to isolate problems valuably.
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