ALBERT

Description: Geobiology explores how Earth's system has changed over the course of geologic history and how living organisms on this planet are impacted by or are indeed causing these changes. For decades, geologists, paleontologists, and geochemists have generated data to investigate these topics. Foundational efforts in sedimentary geochemistry utilized spreadsheets for data storage and analysis, suitable for several thousand samples, but not practical or scalable for larger, more complex datasets. As results have accumulated, researchers have increasingly gravitated toward larger compilations and statistical tools. New data frameworks have become necessary to handle larger sample sets and encourage more sophisticated or even standardized statistical analyses. In this paper, we describe the Sedimentary Geochemistry and Paleoenvironments Project (SGP; Figure 1), which is an open, community-oriented, database-driven research consortium. The goals of SGP are to (1) create a relational database tailored to the needs of the deep-time (millions to billions of years) sedimentary geochemical research community, including assembling and curating published and associated unpublished data; (2) create a website where data can be retrieved in a flexible way; and (3) build a collaborative consortium where researchers are incentivized to contribute data by giving them priority access and the opportunity to work on exciting questions in group papers. Finally, and more idealistically, the goal was to establish a culture of modern data management and data analysis in sedimentary geochemistry. Relative to many other fields, the main emphasis in our field has been on instrument measurement of sedimentary geochemical data rather than data analysis (compared with fields like ecology, for instance, where the post-experiment ANOVA (analysis of variance) is customary). Thus, the longer-term goal was to build a collaborative environment where geobiologists and geologists can work and learn together to assess changes in geochemical signatures through Earth history. With respect to the data product, SGP is focused on assembling a well-vetted and comprehensive dataset that is tractable to multivariate statistical analyses accounting for multiple geological and methodological biases. Phase 1 of the project, which focused on the Neoproterozoic and Paleozoic, has been completed. Future phases will capture a broader range of geologic time, data types, and geography. The database contains tens of thousands of unpublished data points provided by consortium members, as well as detailed metadata that go beyond what is contained in papers. In many cases, these represent measurements that are tangential to a given published study but still of high utility to database studies; these allow the community to address questions that would be impossible to answer solely with the published data. For instance, in order to use a proxy such as Mo/TOC (total organic carbon) ratios in mudrocks deposited under a euxinic water column, the full suite of trace metal, iron speciation, and total organic carbon data is needed. Likewise, geospatial information is required to account for sampling biases, and many statistical learning approaches cannot accept, or have difficulty with, incomplete geological predictor variables. Ultimately, it is this complete data matrix that will allow for SGP’s most insightful analyses.

Description: This case study, utilizing surface and upper-air data, has attempted to shed light on the mechanisms that exerted control on two contrasting rainfall episodes in Hawaii [in the dry winter of 1981 and wet winter of 1982].

Description: Data from ichthyoplankton surveys conducted in 1972 and from1977 to 1999 (no data were collected in 1980) by the Alaska Fisheries Science Center (NOAA, NMFS) in the western Gulf of Alaska were used to examine the timing of spawning,geographic distribution and abundance, and the vertical distribution of eggs and larvae of flathead sole(Hippoglossoides elassodon). In the western Gulf of Alaska, flathead sole spawning began in early April and peaked from early to mid-May on the continental shelf. It progressedin a southwesterly direction along the Alaska Peninsula where three main areas of flathead sole spawning wereindentified: near the Kenai Peninsula, in Shelikof Strait, and between the Shumagin Islands and Unimak Island. Flathead sole eggs are pelagic, and their depth distribution may be a function of their developmental stage.Data from MOCNESS tows indicated that eggs sink near time of hatching and the larvae rise to the surface to feed. The geographic distribution of larvae followed a pattern similar to the distribution of eggs, only it shifted about one month later. Larval abundance peaked from early to mid-June in the southern portion of Shelikof Strait. Biological and environmental factors may help to retain flatheadsole larvae on the continental shelf near their juvenile nursery areas.

Description: Nuclear RNA and DNA in muscle cell nuclei of laboratory-reared larvae of Walleye Pollock (Gadus chalcogrammus) were simultaneously measured through the use of flow cytometry for cell-cycle analysis during 2009–11. The addition of nuclear RNA as a covariate increased by 4% the classification accuracy of a discriminant analysis model that used cell-cycle, temperature, and standard length to measure larval condition, compared with a model without it. The greatest improvement, a 7% increase in accuracy, was observed for small larvae (〈6.00 mm). Nuclear RNA content varied with rearing temperature, increasing as temperature decreased. There was a loss of DNA when larvae were frozen and thawed because the percentage of cells in the DNA synthesis cell-cycle phase decreased, but DNA content was stable during storage of frozen tissue.

Description: High salinity estuaries in the southeastern U.S. have experienced increased inputs of contaminants from nonpoint source (NPS) urban runoff and decreases in habitat due tofilling of wetlands and dock/bulkhead construction. Urbanization may pose significant risks to estuarine fauna, particularly crustaceans. The grass shrimp of the genusPalaemonetes, is one of the dominant species found in estuarine tidal creeks, accounting for greater than 50% of all macropelagic fauna on an annual basis. Spatial analytical and geographic information system techniques were used to determine which factors influenced the Palaemonetes population structures in a South Carolina bar-built estuary surrounded by urban development. Impacts from land use practices were investigated using concentric circular buffers around study sites. Factors investigated included sediment-associated polycyclic aromatic hydrocarbons concentration, land use classification, percent impervious surfaces, and other selected urban factors. Geographic information system and statistical modeling showed quantitative relationships betweenland use class and impacts on Palaemonetes density. The study suggests that habitat loss is a major factor influencing grass shrimp densities. Multiple regression modeling suggests a significant relationship between habitat alterations and Palaemonetes densities.

Description: EXTRACT (SEE PDF FOR FULL ABSTRACT):During the past hundred years, mountain glaciers throughout the world have retreated significantly from moraines built during the previous several centuries. In the 1930s, Francois Matthes of the U.S. Geological Survey concluded that the moraines represent the greatest advances of glaciers since the end of the last glacial age, some 10,000 years earlier, and informally referred to this late Holocene interval of expanded ice cover as the Little Ice Age.

Description: Whenever human beings have looked out on the sea, they have seen whales. First from the shore and later from ships when humanity entered the ocean realm as seafarers, we haveresponded to seeing these creatures with awe and wonder. Even when we hunted whales, a period well chronicled both in history and in literature, the sight of a whale brought an adrenaline rush that was not totally linked to potential economic gain. The first trips on boats specificallyto watch, rather than hunt, whales began around 45 years ago in Southern California where the migrating gray whales, seen in the distance from land, drew vessels out for a closer look. Since that time whalewatching has boomed, currently conducted in over 40 countries around the world,including Antarctica, and estimated by economists at the Whale and Dolphin Conservation Society to have a 1999 worldwide economic value of around $800 million USD. The economic contribution to local coastal communities is particularly significant in developing countries andthose where declining fish populations (and in some cases like the Japanese, international bans on whaling) have driven harvesters to look for viable alternatives. Clearly, whalewatching is now, in many places around the world, a small but thriving part of the regional economy. Like in thedays of whaling, we still get the rush, but for some, money is back contributing to the physiological response. (PDF contains 90 pages.)

Description: Muscle extracts of Pacific whiting, Merluccius productus, and arrowtooth flounder, Atheresthes stomias, were assayed for proteolytic activity using azocasein as a substrate. Pacific whiting extracts showed maximum activity at pH 5.0-5.2 and a temperature of 50°C, while arrowtooth flounder extracts had maximum activity at pH 5.5 and 55°C. Three sources of inhibitors (potatoes, egg white, beef plasma protein) were evaluated in vitro for inhibition of protease activity. All three were found to be effective inhibitors in crude muscle extracts. Further studies utilizing these inhibitors in surimi showed that potato was equivalent to both egg white and beef plasma protein in preserving the gel forming characteristics ofheated kamaboko in both species.

Description: Tissues from Cook Inlet beluga whales, Delphinapterus leucas, that were collected as part of the Alaska Marine Mammal Tissue Archival Project were analyzed for polychlorinated biphenyls (PCB’s), chlorinated pesticides, and heavy metals and other elements. Concentrations of total PCB’s (ΣPCB’s), total DDT (ΣDDT), chlordane compounds, hexachlorobenzene (HCB), dieldrin, mirex, toxaphene, and hexachlorocyclohexane (HCH) measured in Cook Inlet beluga blubber were compared with those reported for belugas from two Arctic Alaska locations (Point Hope and Point Lay), Greenland, Arctic Canada, and the highly contaminated stock from the St. Lawrence estuary in eastern Canada. The Arctic and Cook Inlet belugas had much lower concentrations (ΣPCB’s and ΣDDT were an order of magnitude lower) than those found in animals from the St. Lawrence estuary. The Cook Inlet belugas had the lowest concentrations of all (ΣPCB’s aver-aged 1.49 ± 0.70 and 0.79 ± 0.56 mg/kg wet mass, and ΣDDT averaged 1.35 ± 0.73 and 0.59 ± 0.45 mg/kg in males and females, respectively). Concentrations in the blubber of the Cook Inlet males were significantly lower than those found in the males of the Arctic Alaska belugas (ΣPCB’s and ΣDDT were about half). The lower levels in the Cook Inlet animals might be due to differences in contaminant sources, food web differences, or different age distributions among the animals sampled. Cook Inlet males had higher mean and median concentrations than did females, a result attributable to the transfer of these compounds from mother to calf during pregnancy and during lactation. Liver concentrations of cadmium and mercury were lower in the Cook Inlet belugas (most cadmium values were 〈1 mg/kg and mercury values were 0.704–11.42 mg/kg wet mass), but copper levels were significantly higher in the Cook Inlet animals (3.97–123.8 mg/kg wet mass) than in Arctic Alaska animals and similar to those reported for belugas from Hudson Bay. Although total mercury levels were the lowest in the Cook Inlet population, methylmercury concentrations were similar among all three groups of the Alaska animals examined (0.34–2.11 mg/kg wet mass). As has been reported for the Point Hope and Point Lay belugas, hepatic concentrations of silver were re

Description: We hypothesize that the impact of PCB desorption from resuspended sediments depends upon the intensity of the resuspension (which scales to bottom stress in the absence of organisms), the rate at which each congener desorbs (which depends on the size and hydrophobicity of the chemical, the relative amount of 'labile' and 'resistant' forms, and the size distribution of the suspended particles), and the residence time of the particles in the water column (which depends on the time-variable water column turbulence regime and the particle settling velocities). In order to accurately quantify the impact of PCB desorption from Hudson River sediments, we are conducting experiments that realistically mimic bottom shear stress and water column turbulence and rapidly measure PCB congener release. The objectives of this study are to measure the kinetics of PCB congener desorption from Hudson River sediments under realistic bottom shear and water column turbulence conditions and to quantify the impact of shear stress and contaminant aging on PCB desorption kinetics.

Description: Hudson River Foundation

Description: Ref. No. [UMCES] CBL 004-018