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Geology topics

J. P. Bennett

Publications and source records attributed to J. P. Bennett.

At least 19 recordsLinked to original sources

Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierrae from California

An unusual dark blue-green lichen, Lecanora sierrae , was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour.

Lichenologist

Degradation of the disease-associated prion protein by a serine protease from lichens

The disease-associated prion protein (PrP(TSE)), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrP(TSE) inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrP(TSE). Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrP(TSE)-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrP(TSE) and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted.

PLoS ONE

Factors to consider for trace element deposition biomonitoring surveys with lichen transplants

A trace element deposition biomonitoring experiment with transplants of the fruticose lichen Evernia prunastri was developed, aimed at monitoring the effects of different exposure parameters (exposure orientation and direct rain) and to the elements Ti, V, Cr, Co, Cu, Zn, Rb, Cd, Sb and Pb. Accumulations were observed for most of the elements, confirming the ability of Evernia transplants for atmospheric metal deposition monitoring. The accumulation trends were mainly affected by the exposure orientation and slightly less so by the protection from rain. The zonation of the trace elements inside the thallus was also studied. It was concluded that trace element concentrations were not homogeneous in Evernia, thus imposing some cautions on the sampling approach. A nuclear microprobe analysis of an E. prunastri transplanted thallus in thin cross-sections concluded that the trace elements were mainly concentrated on the cortex of the thallus, except Zn, Ca and K which were also present in the internal layers. The size of the particles deposited or entrapped on the cortex surface averaged 7????m. A list of key parameters to ensure the comparability of surveys aiming at observing temporal or spatial deposition variation is presented. ?? 2006 Elsevier B.V. All rights reserved.

Tête Ronde, Gif-sur-Yvette

Field responses of Prunus serotina and Asclepias syriaca to ozone around southern Lake Michigan

Higher ozone concentrations east of southern Lake Michigan compared to west of the lake were used to test hypotheses about injury and growth effects on two plant species. We measured approximately 1000 black cherry trees and over 3000 milkweed stems from 1999 to 2001 for this purpose. Black cherry branch elongation and milkweed growth and pod formation were significantly higher west of Lake Michigan while ozone injury was greater east of Lake Michigan. Using classification and regression tree (CART) analyses we determined that departures from normal precipitation, soil nitrogen and ozone exposure/peak hourly concentrations were the most important variables affecting cherry branch elongation, and milkweed stem height and pod formation. The effects of ozone were not consistently comparable with the effects of soil nutrients, weather, insect or disease injury, and depended on species. Ozone SUM06 exposures greater than 13 ppm-h decreased cherry branch elongation 18%; peak 1-h exposures greater than 93 ppb reduced milkweed stem height 13%; and peak 1-h concentrations greater than 98 ppb reduced pod formation 11% in milkweed. Decreased cherry branch elongation, milkweed stem height and pod production, and foliar injury on both species occurred at sites around southern Lake Michigan at ozone exposures of 13 SUM06 ppm-h and 93a??98 ppb peak hourly.

Illinois, Indiana, Michigan, Wisconsin

Elemental content of lichens of the Point Reyes Peninsula, northern California

The Point Reyes peninsula in northern California is about 45 km northwest of San Francisco and occasionally receives air masses from the city contributing to haze and lowered visibility. Although gaseous pollutants are not a problem, fine particulates containing carbon and other elements are measurable at the park. In this study, five lichen species were sampled along a 40-km linear transect from southeast to northwest from the town of Bolinas at the southern end of the peninsula. Elevated levels of Na and S and the Na/S ratio at localities nearer the ocean confirmed there is a definite marine aerosol influence on lichen elemental content. Elevated potassium and mercury concentrations were also found at high elevation sites that intercept fog. However, arsenic and lead were found to decrease with distance from Bolinas along the transect, suggesting these two elements originate in the fine particulate haze that enters the park from San Francisco. Concentrations of elements were not at enriched levels for other lichen species. A possible local influence of roads on element content needs further study.

California

Element content of Xanthoparmelia scabrosa growing on asphalt in urban and rural New Zealand

Xanthoparmelia scabrosa is a foliose lichen that grows abundantly on pedestrian and automobile asphalt in New Zealand, which are considered inhospitable habitats for lichens. Samples were collected at eight localities ranging from urban streets to very rural roads and analyzed for 28 chemical elements in order to determine elemental chemistry and to test hypotheses about tolerance mechanisms. Anthropogenic elements (Cu, Pb, and Zn) decreased significantly from urban to rural areas, while nutritional elements (K, P, and S) increased. Samples from urban areas contained 10% calcium. Sulfur was elevated at both urban and rural sites, possibly due to pollution in the former site and higher levels of sulfur-containing scabrosin esters at the rural sites. The ability of this lichen to accumulate high levels of Cu, Pb and Zn may make it useful as a remediation tool.

North Island

Elemental chemistry of four lichen species from the Apostle Islands, Wisconsin, 1987, 1995 and 2001

Four lichen species sampled three times over a 15-year time span at four of the Apostle Islands, Wisconsin were analyzed for 16 chemical elements in order to determine time trends and spatial patterns. Factor analyses of the data revealed that elements associated with soils (Al, Cr, Fe, Na, Ni and S) have increased over the study period, while nutrient and pollutant elements (Cu, K, P, Pb and Zn) have decreased. Four other elements (Ca, Cd, Mg and Mn) were unchanged over time. Cladina rangiferina , a terricolous species, contained the lowest concentrations of all elements, while the corticolous species Evernia mesomorpha was highest in soil elements, Hypogymnia physodes was highest in Ca, Cd, Mg and Mn, and Parmelia sulcata was highest in the nutritional elements. Lichens on islands within 3–4 km of the mainland were highest in soil elements, which decreased with distance from the mainland. Elements that were 18–43% greater on the nearest islands were significantly different between near and far islands. Eight elements (Al, Ca, Cd, K, Mg, Mn, P and S) exceeded enrichment levels for Hypogymnia physodes , suggesting possible contamination problems for this species. Although Pb has decreased significantly over the time period, other elements have increased in the lichens while decreasing in the atmosphere, suggesting that accumulation in the environment is continuing.

Wisconsin

Science for avian conservation: Priorities for the new millennium

Over the past decade, bird conservation activities have become the preeminent natural resource conservation effort in North America. Maturation of the North American Waterfowl Management Plan (NAWMP), establishment of Partners in Flight (PIF), and creation of comprehensive colonial waterbird and shorebird conservation plans have stimulated unprecedented interest in, and funding for, bird conservation in the United States, Canada, Mexico, and other countries in the western hemisphere. Key to that success in the United States has been active collaboration among federal, state and local governments, conservation organizations, academia, and industry. The U.S. Department of the Interior (DOI), which has primary statutory responsibility for migratory bird conservation and management, has been a key partner. Despite the great strides that have been made in bird conservation science, historical approaches to research and monitoring have often failed to provide sufficient information and understanding to effectively manage bird populations at large spatial scales. That shortcoming, and the lack of an integrated strategy and comprehensive set of research priorities, is more evident in light of the goals established by the North American Bird Conservation Initiative (NABCI). The NABCI is a trinational, coalition-driven effort to provide an organizational umbrella for existing conservation initiatives. The expanded focus of NABCI and individual bird conservation initiatives is to work together in an integrated, holistic fashion to keep common birds common and to increase populations of declining, threatened, and endangered species. To assist bird conservation initiatives in defining goals and developing new approaches to effective research, the U.S. Geological Survey (USGS), the research agency of DOI, convened a workshop, “Science for Avian Conservation: Understanding, Modeling, and Applying Ecological Relationships,” on 31 October–2 November 2000, which brought together 51 scientists from USGS, as well as scientists and conservationists from other agencies and organizations actively participating in NABCI. As the lead federal agency involved in bird conservation research, USGS has a clear legislative mandate to provide scientific information upon which future management plans and actions will be built. This article summarizes key issues and recommendations that arose from that workshop. The principal goal of the workshop was to guide USGS in defining its role, assessing capabilities, and directing future agency planning in support of bird conservation. A major component was to identify key areas of research needed in this new era of bird conservation science. Although tailored to the mission of USGS, workshop recommendations visualize a bold direction for future avian conservation science in which research and monitoring work in tandem with management to increase our understanding of avian populations and the processes that affect them. The USGS is a science agency whose role is to provide objective scientific information to management agencies and therefore is not directly involved in high-level resource policy-making or on-the-ground management decision making. Nevertheless, it is important to note that effective policy decision making must integrate the best available science with political and economic realities to achieve successful avian conservation—an important subject acknowledged in the workshop, but largely beyond its scope of discussion. Williams (2003) questions regarding how scientific information can be effectively communicated to decision makers and incorporated into natural resource policy. Without an aggressive vision and the willingness of researchers, managers, and policy makers to implement it, conservation of North American birds is likely to proceed without the full benefit of scientific investigation. These recommendations represent the principal conclusions drawn by workshop participants and do not necessarily reflect official USGS policy.

The Auk

Lichens promote flowering Opuntia fragilis in west-central Wisconsin

Clumps of the cactus Opuntia fragilis growing in association with mats of the lichens Cladina mitis , Cladina rangiferina and a spikemoss, Selaginella rupestris , were discovered in an agricultural field in Pepin County, Wisconsin, that had been abandoned for over 50 y. The association appeared to be beneficial to the cactus, which flowered almost exclusively in the presence of lichens. Of 294 cactus clumps examined in 2001, 127 grew in the presence of lichen mats and, of these, 24 flowered, producing 91 flowers, while none of the cacti growing in the absence of lichens flowered. In 2002, 19 out of 265 cactus clumps flowered, all but one in the presence of lichens. All sizes of cacti in the presence of lichens flowered and the probability of flowering increased with cactus size. In addition, the cacti that flowered had cladodes that were on average 19% heavier than those of cacti that did not flower. The presence of lichens lowered summer soil temperatures 2–4 C compared to soil temperatures in the absence of lichens. Cooler soil temperatures conserve soil moisture better, which may enhance flowering in these cacti.

Wisconsin

Algal layer ratios as indicators of air pollutant effects in Permelia sulcata

Parmelia sulcata Taylor is generally believed to be fairly pollution tolerant, and consequently it is sometimes collected in urban and/or polluted localities. The condition of these specimens, however, is not always luxuriant and healthy. This study tested the hypothesis that total thallus and algal layer thickness, and the algal layer ratio would be thinner in polluted areas, thus allowing these characters to be used a indicators of air pollutant effects. Herbarium specimens were studied from 16 different localities varying in pollution level. The thallus and algal layers and ratio were not affected by year or locality of sampling, but decreased 11, 31 and 21% respectively between low and high pollution level localities. These results agreed with earlier studies using other species, but further work is needed to clarify the effects of geography and substrate on these phenomena.

Delaware, Indiana, Iowa, Massachusetts, Michigan,

Searching for biological specimens from midwestern parks: Pitfalls and solutions

This paper describes the results of searches of herbarium and museum collections and databases for records of vertebrate and vascular plant specimens that had been collected in 15 midwestern National Park System units. The records of these specimens were previously unknown to the National Park Service (NPS). In the course of our searches, numerous obstacles were encountered that prevented us from fully completing our task. These ranged from difficulties with the way databases are structured, to poor record-keeping, to incomplete or incorrect information on the actual location of specimens within collections. Despite these problems, we are convinced that the information to be gained from such searches in invaluable, and we believe that our experience, and the recommendations we offer, may well prove instructive to others undertaking this kind of work.

Arkansas, Indiana, Iowa, Kansas, Minnesota, Missou

Type characters of non-native plant species in Great Lakes national parks (USA)

Non-native plant species are increasing in frequency and abundance in many natural areas in the United States. In Midwestern National Parks, as much as one third of the flora may be non-native. It was hypothesized that botanical characters of these species could be used to typify them and improve the methods of predicting invasions. Data on 19 characters of 341 non-native species from the four Great Lakes national lakeshores (Apostle Islands, Indiana Dunes, Pictured Rocks, and Sleeping Bear Dunes) and invasive non-native species for the State of Wisconsin were collected and studied. For many of the species, little data could be found, but for 139 of them, data were collected for at least 80% of the characters. The frequencies of classes of the characters were tabulated and ranked to typify the most common non-native species. This led to a description of a 'type species' just for these four National Parks. Three species of Cirsium, including Canada (C. arvense), marsh (C. palustre) and bull thistle (C. vulgare), matched the type species better than other species. C. vulgare occurs in more National Parks than the other thistles.

Indiana, Michigan, Wisconsin

16-year trends in elements of lichens at Theodore Roosevelt National Park, ND

An epiphytic lichen and a soil lichen in two very closely related genera (Parmelia sulcata and Xanthoparmelia chlorochroa, respectively) were sampled 16 years apart at Theodore Roosevelt National Park in North Dakota and measured for their elemental content. Mercury and cadmium decreased approximately 30% over the time period in both species. Sulfur decreased 8% in the epiphytic species, but increased 20% in the soil lichen. Factor analysis revealed that soil elements were higher in the soil lichen, indicating there was some soil contamination in that species. A relationship between iron and titanium was found only in the soil lichen. Sulfur and mercury were highly enriched in both species relative to the soil, which suggests that the atmosphere is a contributing source of these elements. New baseline values were calculated, 22 elements for both species, although it is not recommended that the soil lichen be sampled in the future.

North Dakota

Heavy metals in wild rice from northern Wisconsin

Wild rice grain samples from various parts of the world have been found to have elevated concentrations of heavy metals, raising concern for potential effects on human health. It was hypothesized that wild rice from north-central Wisconsin could potentially have elevated concentrations of some heavy metals because of possible exposure to these elements from the atmosphere or from water and sediments. In addition, no studies of heavy metals in wild rice from Wisconsin had been performed, and a baseline study was needed for future comparisons. Wild rice plants were collected from four areas in Bayfield, Forest, Langlade, Oneida, Sawyer and Wood Counties in September, 1997 and 1998 and divided into four plant parts for elemental analyses: roots, stems, leaves and seeds. A total of 194 samples from 51 plants were analyzed across the localities, with an average of 49 samples per part depending on the element. Samples were cleaned of soil, wet digested, and analyzed by ICP for Ag, As, Cd, Cr, Cu, Hg, Mg, Pb, Se and Zn. Roots contained the highest concentrations of Ag, As, Cd, Cr, Hg, Pb, and Se. Copper was highest in both roots and seeds, while Zn was highest just in seeds. Magnesium was highest in leaves. Seed baseline ranges for the 10 elements were established using the 95% confidence intervals of the medians. Wild rice plants from northern Wisconsin had normal levels of the nutritional elements Cu, Mg and Zn in the seeds. Silver, Cd, Hg, Cr, and Se were very low in concentration or within normal limits for food plants. Arsenic and Pb, however, were elevated and could pose a problem for human health. The pathway for As, Hg and Pb to the plants could be atmospheric.

Wisconsin