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The recently-emerged amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) has had an unprecedented impact on global amphibian populations, and highlights the urgent need to develop effective mitigation strategies. We conducted in-situ antifungal treatment experiments in wild populations of the endangered mountain yellow-legged frog during or immediately after Bd-caused mass die-off events. The objective of treatments was to reduce Bd infection intensity (“load”) and in doing so alter frog-Bd dynamics and increase the probability of frog population persistence despite ongoing Bd infection. Experiments included treatment of early life stages (tadpoles and subadults) with the antifungal drug itraconazole, treatment of adults with itraconazole, and augmentation of the skin microbiome of subadults with Janthinobacterium lividum, a commensal bacterium with antifungal properties. All itraconazole treatments caused immediate reductions in Bd load, and produced longer-term effects that differed between life stages. In experiments focused on early life stages, Bd load was reduced in the 2 months immediately following treatment and was associated with increased survival of subadults. However, Bd load and frog survival returned to pre-treatment levels in less than 1 year, and treatment had no effect on population persistence. In adults, treatment reduced Bd load and increased frog survival over the entire 3-year post-treatment period, consistent with frogs having developed an effective adaptive immune response against Bd. Despite this protracted period of reduced impacts of Bd on adults, recruitment into the adult population was limited and the population eventually declined to near-extirpation. In the microbiome augmentation experiment, exposure of subadults to a solution of J. lividum increased concentrations of this potentially protective bacterium on frogs. However, concentrations declined to baseline levels within 1 month and did not have a protective effect against Bd infection. Collectively, these results indicate that our mitigation efforts were ineffective in causing long-term changes in frog-Bd dynamics and increasing population persistence, due largely to the inability of early life stages to mount an effective immune response against Bd. This results in repeated recruitment failure and a low probability of population persistence in the face of ongoing Bd infection.

Ground water at the Norman Landfill Research Site is contaminated by a leachate plume emanating from a closed, unlined landfill formerly operated by the city of Norman, Oklahoma, Ground water contaminated by the leachate plume is known to be elevated in the concentration of many, organic and inorganic constituents. Specific conductance, alkalinity, chloride, dissolved organic carbon, boron, sodium, strontium, and deuterium in ground water are considered to be indicators of the leachate plume at this site. Leaf samples of broad-leafed cottonwood, Populus deltoides, were collected from 57 sites around the closed landfill. Cottonwood, a phreatophyte or “well plant,” functions as a & surrogate well and serves as a ground water quality sampler. The leaf samples were combusted to ash and analyzed by instrumental neutron activation for 35 elements and by prompt-gamma instrumental neutron activation, for boron. A monitoring well was located within a few meters of a sampled cottonwood tree at 15 of the 57 sites, and ground water samples were collected from these monitoring wells simultaneously with a leaf sample. The chemical analyses of the ground water and leaf samples from these 15 sites indicated that boron, bromine, sodium, and strontium concentrations in leaves were significantly correlated with leachate indicator constituents in ground water. A point-plot map of selected percentiles indicated high concentrations of boron, bromine, and sodium in leaf ash from sites downgradient of the most recent landfill and from older landfills nearby. Data from leaf analysis greatly extended the known areal extent of the leachate plume previously determined from a network of monitoring wells and geophysical surveys. This phytosgeochemical study provided a cost-effective method for assessing the extent of a leachate plume from an old landfill. Such a method may be useful as a preliminary sampling tool to guide the design of hydrogeochemical and geophysical studies.

Ground and surface water in and along the broad floodplain of Willow Creek below Creede, Colorado, are contaminated by drainage from various mine adits and waste rock piles above the town and by leachates from a gravel-capped tailings pile below. These waters have been sampled through a set of 18 monitoring wells and found to have elevated in metal concentrations, especially of zinc (Zn) and cadmium (Cd). Zinc is of most concern because of its known toxicity to freshwater fish (e.g., Beregeri and Patil, 1986; Farag et. al., 1999; Hilmy et. al., 1987). Moreover, the mouth of Willow Creek spills into the Rio Grande River, a prime trout fishery. At issue, then, is the impact of the water quality of Willow Creek as it enters the Rio Grande River. In an attempt to find a simple and cost-effective method to monitor contamination of surface and ground water in areas impacted by mining, we measured the content of 37 elements in willows (sandbar willow, Salix exigua, and one blue willow, Salix drummondiana), which grow abundantly in this study area. We collected leaf samples at 14 sites, mostly on the Willow Creek floodplain below the town of Creede, Colorado. Willow functions as surrogate water well and a groundwater quality sampler because its roots usually extend into the ground water region (Robinson, 1956). Willows have also been shown to accumulate far more Cd than do other shrubs and trees in mineralized areas. Because Cd associates closely with Zn in plant tissue, and willow is fairly common at the project site, willow proved to be an ideal plant for our study. The washed and dried leaf samples were macerated in a Wiley mill and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) for 37 elements. Monitoring wells were located close to the willow sample sites at 5 of the 14 locations. However, groundwater samples were not collected simultaneously from these monitoring wells and thus no comparisons could be made between the two media. Data from leaf analysis revealed clearly that the willows were highly enriched in Zn and Cd, more than any other of the 37 elements determined. A few sites on the shoreline of the Rio Grande River upstream from its confluence of Willow Creek provided values that can be considered background, which ran about two orders of magnitude less than the maximum concentrations found in samples at the base of the capped tailings. A few willow samples previously collected and analyzed from an anomalous seep seven miles below Willow Creek yielded elevated concentrations of both Zn and Cd, but not nearly to the extent as those sampled along the Willow Creek floodplain. This phytogeochemical study provided a cost-effective method for assessing the extent of a leachate plume from generally non-point sources. Such a method may be useful as a preliminary sampling tool to guide the design of hydrogeochemical and geophysical studies.

We have identified a large, anomalously limonitic area in Cenozoic gravels on Lordsburg Mesa near Lordsburg, New Mexico, using Landsat images. Our interpretation of the geophysical and geochemical data suggests the exploration hypothesis that the Lordsburg Mesa limonite anomaly is the surface expression of a chemical trap that may contain concentrations of uranium similar to calcrete-uranium deposits.Ground water originating in the Big Burro Mountains, where uranium vein deposits are known, drains through the Lordsburg Mesa area. This ground water is apparently forced near the surface by a buried bed-rock ridge along the west side of the limonite anomaly. The resulting changes in ground-water chemistry may be precipitating uranium along the eastern margin of the limonite anomaly.

Geochemical studies of waters, alluvial deposits, and vegetation revealed that aluminum, beryllium, cobalt, copper, molybdenum, and nickel occurred in anomalously high concentrations in an area adjacent to a claypit in Callaway, County, Mo. The principal sources of these and other elements that were found in anomalous amounts are believed to be the clay, shale, limestone, coal, and pyrite that were exposed when the clay was mined. These geologic materials, although they contain normal concentrations of elements, constitute an unusually rich source (compared to typical soils) of certain elements for the plants and waters of the area. Pyrite, especially, affects the mobility of some of these elements because, by weathering, it produces sulf uric acid which increases the solubility of certain compounds. On the two ranches studied, young beef cattle exposed to anomalous element concentrations in the flood plain below the claypile experienced a severe interference syndrome due to an imbalance of minerals or other nutrients in their feed or water, or both. The disturbance in metabolism of cattle grazing on the pastures effected by the claypile was most similar to chronic molybdenosis. Imbalance of copper and molybdenum, in addition to those of sulfate, cobalt, and other substances, may have contributed to this syndrome. Anomalous concentrations of elements may exist at many other locations in Missouri and throughout the Midwest where similar materials are brought to the surface by clay and coal strip-mine operations (especially if pyrite is present).

In the fall of 1975, cattle grazing to the north of an abandoned uranium mine on Flint Butte in Harding County, S. Dak., showed signs of molyhdenosis, a disease due to molybdenum-induced copper deficiency. To identify the source of the problem, plant, water, and soil samples were collected on a grid design over a 16 km* (- 9 miles*) area around Flint Butte. Uranium, molybdenum, and copper concentrations were determined in western wheatgrass (Agropyron smith@ and sweetclover (Mililotur officindis); molybdenum and copper concentrations and pH were determined in pond waters; and the pH of soils was determined. Ratios of copper to molybdenum in the forage were found to be below 2:1, the lowest value considered safe for cattle. Molybdenum concentrations in some surface waters were extremely high. These conditions are related to the outcrop of uranium- and molybdenumbearing llgnites at Flint Butte and in the nearby Flint Hills. Similar lignites are widespread, and It is likely that nutritional problems of the type e?countered in the Flint Butte area exist in similar geologic terrain over a broad region of the northern Great Plains.

Analysis-of-variance procedures have demonstrated that the concentrations of most elements in Parmelia chlorochroa Tuck. appear to be remarkably uniform throughout the Powder River Basin. Of the 26 elements studied, only 7 (aluminum, cadmium, copper, fluorine, lead, selenium and silicon) showed statistically significant "regional" variation at scales above 10 km. The element content of samples taken at opposite ends of the basin, therefore, is not expected to vary any more, on the average, than that of samples taken only a few kilometers apart. These results allow us to judge the geochemical normalcy of any subsequent samples of this terricolous lichen collected from anywhere in the basin. Baselines, expressed as 95% expected ranges, are given for those 19 elements lacking significant regional variation. As part of a reconnaissance study of landscape geochemistry initiated in the fall of 1973 in the Powder River Basin of Wyoming and Montana, samples of the terricolous lichen Parmelia chlorochroa Tuck.-sensu lato-were collected along with samples of Artemisia tridentata Nutt. (big sagebrush) and Bouteloua gracilis (H.B.K.) Lag. (blue grama). The underlying soil was also sampled at three depths of the profile. The intent of this study was to describe the magnitude of the geochemical variation in these natural materials as they occurred across the basin and to provide at least provisional baselines where appropriate. Results pertaining to the soils are given in Tidball and Ebens (1976); preliminary results from study of the plants are given in Tidball, Erdman and Ebens (1974) and in Erdman and Gough (1975). Although the cryptogamic literature is replete with studies based on lichens as pollution indicators (see, for example, Ferry, Baddeley & Hawksworth, 1973), most of the studies have dealt with changes in community structure or with the physiological response of species (Brandt, 1972). Identification of the specific contaminants in such studies is commonly difficult. Literature on the element composition of lichen tissue appears to be much more limited, and reports on environmental contamination from point sources are particularly sparse. Tuominen and Jaakkola (1973), however, provided an excellent review of the literature on absorption and accumulation of mineral elements and radioactive nuclides in lichens. The initial interest in the trace-elment chemistry of lichens focused on radio-isotopes, because of the concern in the 1950's ' We wish to thank W. A. Weber, University of Colorado Museum, for the identification of vouchers. R. J. Ebens, G. L. Feder and R. R. Tidball assisted in collecting the samples as part of a basin-wide geochemical survey. Chemical analyses were performed by T. F. Harms, H. G. Neiman and C. S. E. Papp in the Denver laboratories of the U.S. Geological Survey. 2 U.S. Geological Survey, Denver, Colorado 80225. This content downloaded from 157.55.39.72 on Thu, 15 Sep 2016 05:54:44 UTC All use subject to http://about.jstor.org/terms 1977] ERDMAN & GOUGH: ELEMENT CONTENT VARIATION IN PARMELIA 293 4-inP?,w iltij:d:i'Y::::~`-:.I dmwii&-iL :s lkAA X;:~;:-:::_: ::?P? ? FIGURE 1. Terrain typical of Powder River Basin. Vegetation is characterized by blue grama (Bouteloua gracilis) and scattered sagebrush (Artemisia tridentata). View from a sampling site in locality 1. over radioactive fallout and because it appeared that radionuclides were much more concentrated in lichens and mosses than in the higher plants (Gorham, 1959). Lounamaa's (1956) study on the non-radioactive trace-element content of a large array of native plants showed that most of the elements occurred in greater amounts in lichens. Because of this apparent capability of lichens, as a whole, to accumulate elements, we thought P. chlorochroa might be an especially useful natural chemical monitor in the Powder River Basin. To our knowledge, this is the first report that attempts to quantify, on a regional basis, the degree of variability in the concentrations of elements among samples of a specific lichen and, further, to identify the geographic scale or scales at which most of the variability occurs. The Powder River Basin encompasses about 50,000 km2 of northeastern Wyoming and southeastern Montana. Mountain ranges and arches surround the basin, but the interior portion is a vast expanse of rolling grassland and sagebrush steppe (Fig. 1), intermittently broken by badland topography and scattered stands of coniferous trees. The average elevation is about 1500 m. Soils throughout the basin show little regional geochemical variation; most of the variability occurs at scales less than a few kilometers (Connor, Keith & Anderson, 1976; Tidball & Ebens, 1976). Interest in the Powder River Basin is becoming nationwide, because the region contains important energy reserves. It has been an important oil and gas producer since the early 1900's (Keefer & Schmidt, 1973), presently yielding more oil and gas than any other area in the Rocky Mountain region. Since the 1950's, uranium has also This content downloaded from 157.55.39.72 on Thu, 15 Sep 2016 05:54:44 UTC All use subject to http://about.jstor.org/terms 294 THE BRYOLOGIST [Volume 80 been produced there, particularly in the southern part of the basin. According to Lieberman (1976), it is one of the three principal uraniferous areas in the United States. The greatest long-term energy potential, however, lies in the thick, widespread deposits of subbituminous coal, totaling probably several hundred billion tons. The importance of such deposits was emphasized by Averitt (1975, p. 71), who stated, "The concentration of coal reserves in this area is larger than that of any other area of comparable size in the United States." Baseline geochemical surveys of the basin are needed, therefore, to establish standards against which changes in local geochemical environments can be measured as coal mining and reclamation, and other energy developments progress.

Copper-to-molybdenum ratios in all but two sweetclover samples collected on spoil at eight coal mines in the Northern Great Plains ranged from 0.44:1 to 5:1. Ratios of 5:1 or less in forage are reported to cause molybdenosis, a nutritional disease occurring in molybdic regions of the world. Therefore, if the major forage on coal-mine spoils is sweetclover or other species with similar Cu:Mn ratios, molybdenosis may be expected to occur in cattle and sheep grazing in these areas.