Lysergic Acid Diethylamide: Its Effects on a Male Asiatic Elephant

A saline pond in a region in Antarctia where other lakes and ponds are frozen remains unfrozen at the prevailing low temperatures. The ecology of the pond is unique. A distinctive aerobic microbial population, though restricted to this natural habitat, adapts to growth in artificial culture. The growth habit of these organisms, as seen in nature and in laboratory culture, indicates a possible relationship between growth at high salt concentration, at low temperatures, and in media of low organic content. On 11 October 1961 a field reconnaissance by Navy helicopter in the south fork of the Wright Valley (longitude 1610 10'E, latitude 77034'S), Victoria Land, Antarctica, revealed an unfrozen pond, although the ambient temperature was -240C. Wright Valley is one of several ice-free valleys in the region from which the continental icecap has receded (1). During the following 3 months several trips were made to the pond. This pond, which we named Don Juan Pond, is approximately 200 m wide and 700 m long; the average depth is 11 cm (2). Small salt deposits occur on the periphery of the pond. The valley surrounding the pond is carved out of metasediments intruded by granites and dolerites. Overlying this valley and forming the higher ridges and peaks in the area is Beacon sandstone, also intruded by dolerites. The pond was formed by moraines blocking both ends of the valley and, at its inception, was probably 10 or more meters deep. Beach lines, now poorly defined, are present 10 m above the water level on the north side of the valley. The influx of water into this basin is 7 DECEMBER 1962 limited. During the summer two small streams drain the moraine to the west. The only other source of moisture is snow falling directly into the small catchment area immediately surrounding the pond. The snowfall averages only a few inches per year. The water is beige-to-brown in color (3); this is attributable in part to pyritic particles in suspension. The pH was 5.4 and probably remains stable, since there is little or no decay of organic matter. The water temperature followed the temperature of the ambient air; from October to December it ranged from -24O to -3.00C, with no variation from surface to bottom. At no time during the period of study was the water frozen. The freezing point of freshly collected samples was -48? -+1 C. The water of Don Juan Pond was compared to the water of Barghoorn and Nichols Pond (4) and also to seawater (5) (Table 1). The specific gravity of Don Juan pond water was 1.2514, and the specific conductance was 790,000 [mho. The concentrations of dissolved solids in Don Juan pond water, in Barghoorn and Nichols pond water, and in seawater were 474,000, 132,620 and 34,480 parts per million, respectively. The salinity of Don Juan Pond was approximately 13.7 times that of seawater and 3.6 times that of Barghoorn and Nicholas Pond. Two deuterium determinations (6) of the pond water gave concentrations of 123.8 ppm and 124.0 ppm. By contrast, a deuterium determination on ocean water in the vicinity of McMurdo Sound gave a concentration of 160.0 ppm. These data, together with the fact that the pond is over 400 feet above sea level and 35 miles from the present coast, suggest a nonmarine origin for the water. The extraordinaryily high salt content is probably due to the weathering of the surrounding rocks, followed by increases in concentration through evaporation. Samples of water for microbiological studies were collected in sterile flasks and returned to the Biological Laboratories at the Naval Air Facility, McMurdo Sound, Ross Island. The water was kept for several days at -220C before laboratory study was begun. Examination of the water samples and sediments showed bacterial rods and cocci which grew in the form of colonies. Microscopic examination of bottom sediments from the pond revealed a diatom frustule, but no growing algae were present. Table 1. Minerals in solution in antarctic waters. Composition (ppm) Don Barghoorn MinJun and Seaeral Pond Pond water Ca 114,000 1,130 400 Mg 1,200 4,890 1,272 Mn <0.05 Na 11,500 33,200 10,556 S04 11 16,150 2,649 Cl 212,000 58,000 18,980