Recent Publications, Reports, and more from the Prairie Research Institute

This list includes recent external publications (e.g., journal articles) authored by institute staff, recent items published by the Institute's Divisions, recent technical reports, and recent dissertations and theses from students whose graduate advisor was an Institute staff member.   For complete catalogs of in-house publications and staff bibliographies of external publications by Division, please see the Institute Publications page on the Prairie Research Institute Library website.

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Recent Publications, Reports, and more from the Prairie Research Institute

  • 2/23/2015
    Author:
    Westcott, Nancy

    Call Number:
    ISWS CR 2015-01
  • 2/23/2015
    Author:
    Kelly, Walt, Panno, Sam, Hackley, Keith

    Call Number:
    ISWS RI-121
  • Publication date: 1 March 2015
    Source:General and Comparative Endocrinology, Volume 213

    Author(s): Loren Merrill , Paulina L. González-Gómez , Vincenzo A. Ellis , Iris I. Levin , Rodrigo A. Vásquez , John C. Wingfield

    Rufous-collared sparrows (Zonotrichia capensis peruviensis) from valleys in the Atacama Desert of Chile, live in an extremely stable environment, and exhibit overlap in molt and reproduction, with valley-specific differences in the proportion of birds engaged in both. To better understand the mechanistic pathways underlying the timing of life-history transitions, we examined the relationships among baseline and stress-induced levels of corticosterone (CORT), testosterone, and bacteria-killing ability of the blood plasma (BKA), as well as haemosporidian parasite infections and the genetic structure of two groups of sparrows from separate valleys over the course of a year. Birds neither molting nor breeding had the lowest BKA, but there were no differences among the other three categories of molt-reproductive stage. BKA varied over the year, with birds in May/June exhibiting significantly lower levels of BKA than the rest of the year. We also documented differences in the direction of the relationship between CORT and BKA at different times during the year. The direction of these relationships coincides with some trends in molt and reproductive stage, but differs enough to indicate that these birds exhibit individual-level plasticity, or population-level variability, in coordinating hypothalamo–pituitary–adrenal axis activity with life-history stage. We found weak preliminary evidence for genetic differentiation between the two populations, but not enough to indicate genetic isolation. No birds were infected with haemosporidia, which may be indicative of reduced parasite pressure in deserts. The data suggest that these birds may not trade off among different life-history components, but rather are able to invest in multiple life-history components based on their condition.





  • 7/5/2015
  • Publication date: May 2015
    Source:Ecological Indicators, Volume 52

    Author(s): Jeffrey W. Matthews , Greg Spyreas , Colleen M. Long

    Floristic Quality Assessment (FQA) was developed as a tool for quantifying the conservation value of natural areas based on their plant species composition and richness. Floristic Quality Assessment is based on Coefficients of Conservatism (C values) assigned to each plant species in a region or state. Each species i, is assigned a value C i , on a scale of 0–10 by expert botanists, based on its fidelity to undegraded natural areas. A criticism of Floristic Quality Assessment is the subjective nature of these C values. Our objective was to determine if C values of individual species are indicative of the C values of species with which they co-occur. If subjectively assigned species’ C values carry meaningful information about plant assemblages and the conservation value of particular habitats, then individual species should tend to co-occur with species of similar C. We tested this hypothesis using occurrences of 1014 species in 388 forests and wetlands across Illinois, USA. Using a null model approach, we found that species co-occurred with species of similar C far more often than would be expected by chance; affirming the predictive ability of subjectively assigned C values. Furthermore, we quantified the extent to which each species was under- or overvalued relative to its co-occurring species assemblages to assess if any species C values were mis-assigned. Woody plants and perennial herbs, as groups, were undervalued as ecological indicators, i.e. their C values were too low. Several non-native species, which, by convention, are assigned a C of zero, were over- or under-valued relative to native species with a C of zero. Based on species occurrences across hundreds of sites, our results indicated that, despite their subjective basis, C values carry considerable ecological information, such that a given species can be used to predict the C values of its co-occurring assemblage. However, some species C values appeared less accurate than others. Our methodological approach could be applied in other states or regions to validate and refine C value assignments.





  • Publication date: 15 August 2014
    Source:Journal of Colloid and Interface Science, Volume 428

    Author(s): Tias Paul , Jinyong Liu , Michael L. Machesky , Timothy J. Strathmann

    Fluoroquinolone (FQ) antibacterials are aquatic contaminants of emerging concern (CEC), and adsorption to mineral surfaces is expected to play an important role in the fate, transport, and treatment of FQs. This study characterizes and models the adsorption of a zwitterionic FQ, ofloxacin (OFX), to goethite (α-FeOOH) over a wide range of pH (3–11), OFX concentration (20–500μM), and electrolyte compositions (0.001–0.1M NaCl and NaClO4). Comparing OFX adsorption to structural analogues demonstrates that the carboxylate group is essential for binding to goethite. ATR-FTIR measurements indicate that FQs complex to goethite surfaces through carboxylate and carbonyl oxygen atoms, and that ClO4 co-adsorbs with OFX. Adsorption of the zwitterionic OFX increases with increasing ionic strength and is enhanced in NaClO4 relative to NaCl electrolyte, whereas adsorption of a non-zwitterionic analogue is insensitive to ionic strength. A CD-MUSIC (charge distribution-multisite complexation) model, incorporating multiple modes of surface complexation constrained by spectroscopic measurements and the crystallographic distribution of goethite surface sites, yields accurate predictions over wide-ranging solution conditions. According to the model, OFX adsorbs predominantly by inner-sphere complexation on terminal surfaces of the rod-shaped goethite crystals in NaCl electrolyte, and OFX-ClO4 ion pairing in NaClO4 induces formation of additional inner- and outer-sphere surface complexes on multiple crystal faces of goethite.

    Graphical abstract

    image




  • Publication date: September 2014
    Source:Journal of Great Lakes Research, Volume 40, Issue 3

    Author(s): Bin Huo , Charles P. Madenjian , Cong X. Xie , Yingming Zhao , Timothy P. O’Brien , Sergiusz J. Czesny

    The round goby (Neogobius melanostomus) is a prevalent invasive species throughout Lake Michigan, as well as other Laurentian Great Lakes, yet little information is available on spatial variation in round goby growth within one body of water. Age and growth of round goby at three areas of Lake Michigan were studied by otolith analysis from a sample of 659 specimens collected from 2008 to 2012. Total length (TL) ranged from 48 to 131mm for Sturgeon Bay, from 50 to 125mm for Waukegan, and from 54 to 129mm for Sleeping Bear Dunes. Ages ranged from 2 to 7years for Sturgeon Bay, from 2 to 5years for Waukegan, and from 2 to 6years for Sleeping Bear Dunes. Area-specific and sex-specific body–otolith relationships were used to back-calculate estimates of total length at age, which were fitted to von Bertalanffy models to estimate growth rates. For both sexes, round gobies at Sleeping Bear Dunes and Waukegan grew significantly faster than those at Sturgeon Bay. However, round goby growth did not significantly differ between Sleeping Bear Dunes and Waukegan for either sex. At all three areas of Lake Michigan, males grew significantly faster than females. Based on catch curve analysis, estimates of annual mortality rates ranged from 0.79 to 0.84. These relatively high mortality rates suggested that round gobies may be under predatory control in Lake Michigan.





  • Publication date: August 2014
    Source:Current Opinion in Insect Science, Volume 2

    Author(s): Gaylord A Desurmont , Ian S Pearse

    Introductions of both plants and herbivorous insects have had tremendous impacts on the world's ecosystems. Novel herbivorous insect–plant interactions are important consequences of introductions of either plants or herbivorous insects. We contrast novel herbivorous insect–plant interactions that arise due to plant versus insect introductions with the aim of understanding whether the causes and consequences of the interaction depend on which party is non-native. The biotic context of the herbivore–plant interaction, in terms of mutualists, predators, and competitors can limit the prevalence of that interaction and varies between native and introduced ranges. Introduced plants can have a large, direct impact on their environment, whereas the impact of introduced herbivorous insects is often mediated through the plants that they consume.





  • Publication date: February 2015
    Source:Quaternary Geochronology, Volume 25

    Author(s): David A. Grimley , Eric A. Oches

    Amino acid racemization (AAR) values measured in gastropod shells are demonstrated to be an important aid for correlations and chronology of fossiliferous loessal, lacustrine, and alluvial Pleistocene units in Illinois, central USA. Aspartic acid (Asx) and Glutamic acid (Glx) D/L values were analyzed on a total of 167 Succinea, Hendersonia, and Pomatiopsis shells from 9 geologic units, with clear stratigraphic relationships, at a total of 18 localities in central and southern Illinois. AAR data from Hendersonia and Succinea are less variable and more normally distributed than Pomatiopsis data, but the latter are locally useful for units lacking preferred genera. Based on analysis of variance tests, Asx- and Glx-D/L data can confidently distinguish among Wisconsin Episode (MIS 2–3), Illinois Episode (MIS 6), late pre-Illinois Episode (MIS 8–14), and early pre-Illinois Episode (MIS 20) deposits. Last glacial Peoria Silt (MIS 2) and Roxana Silt (MIS 3), have mean Asx-D/L values of 0.34–0.37 and 0.42–0.43, respectively, considering all genera. The Illinois Episode Petersburg Silt (∼150 ka) has Asx-D/L ( x ¯ : 0.50–0.56) and Glx- D/L ( x ¯ : 0.17–0.22) ratios that are statistically distinctive from other units. Three late pre-Illinois Episode units (Harkness Silt Member, Belgium Member, and Banner silt units) have similar Asx D/L values ( x ¯ : 0.63–0.71) and, along with stratigraphic context, confirm extensive middle Pleistocene glaciations in the region. Using parabolic kinetic age models, depositional ages of ∼550–250 ka (MIS 14–8) are implied for these units, with a favored correlation with MIS 12 (∼450 ka), a time of especially high global ice volume. The Canteen member, a preglacial alluvium–colluvium below the Harkness Silt, is statistically indistinguishable from other pre-Illinois Episode units with AAR data, but was likely deposited during ∼660–480 ka (MIS 16 or 14), based on parabolic age estimates. The paleomagnetically reversed County Line silt (∼780–830 ka: MIS 20), with the highest mean AAR values, is the oldest known gastropod-bearing Pleistocene unit in Illinois.





  • 7/5/2015
  • Publication date: 1 March 2015
    Source:International Journal of Coal Geology, Volumes 141–142

    Author(s): Susan M. Rimmer , John C. Crelling , Lois E. Yoksoulian

    Numerous examples of coke produced by igneous intrusion into coal have been reported in the Spanish Peaks region of south central Colorado. However, in a recent study of an intruded section of the Raton Formation (Upper Cretaceous-Paleocene) along the Purgatoire River near Medina Plaza, CO, coked bitumen has been observed. This material occurs in “fingers” (hexagonally jointed bodies) in a shaley xenolith within a lamprophyre sill and in carbonaceous Type III shale directly below the sill. The coke fingers are characterized by a remarkable flow mosaic texture, high vitrinite/coke reflectance (average random reflectance between 8% and 9%, but with maximum readings around 14–15%), high anisotropy, abundant devolatilization vacuoles, and an absence of inertinite inclusions. Within the underlying shales, the coked bitumen occurs as pore, void, and fracture linings and fillings. Geochemically, the coke in the fingers has low S1 and S2 values (<0.2 and <3mg HC/g, respectively), and low HI and OI values (<6mg HC/g TOC and <3mg CO2/g TOC, respectively). Within the fingers, there is evidence for multiple stages of accumulation, including coarse-grained circular or ribbon coke frequently containing pores edged by vapor-deposited carbon (pyrolytic carbon), layers of pyrolytic carbon, clusters of spherulitic pyrolytic carbon, and layers of highly porous coke. This coked bitumen is quite different from coked coal from the same locality. The coked coal has a medium-grained circular mosaic texture that is consistent with the high volatile bituminous rank of unaltered coal in the area. The coal-derived coke has similar devolatilization vacuoles but also has numerous inclusions of inertinite macerals such as fusinite and secretinite. A previously reported coal “dike” that had flowed through a sill in the same area also showed circular mosaic texture. These observations suggest that the coke found in this study was not formed by the direct coking of coal, but from a mobile phase (bitumen or pitch) that was subsequently coked by the intrusion. This bitumen was either derived from the abundant coal within the section above the sill, or from the organic matter contained within the Type III carbonaceous shales, or both. Unaltered Type III shale sampled at this site has a HI of ~350mg HC/g TOC suggesting some, albeit limited, capacity to generate petroleum. We suggest that bitumen was generated prior to or during the time of intrusion and was subsequently coked by the high temperatures of the emplaced sill. As the bitumen pooled adjacent to the sill, rapid heating led to the development of mesophase, resulting in a highly anisotropic ribbon mosaic texture on cooling, and vaporization of gases that subsequently condensed along pores, vacuoles, and fractures as pyrolytic carbon and spherulitic pyrolytic carbon. Bitumen within the underlying silty shales was also coked, but to a lesser degree. The texture of this coked bitumen looks very much like commercially produced petroleum coke. This coked bitumen differs from other reports of coked bitumen in its mode of occurrence (coke fingers in a xenolith), ribbon mosaic structure, and extremely high anisotropy and reflectance.





  • Publication date: 16 July 2014
    Source:Journal of Hydrology, Volume 515

    Author(s): Daeryong Park , Momcilo Markus

    The Pecatonica River and several other streams in the Wisconsin Driftless area show a decreasing trend in annual peak flows. Previous studies of the Pecatonica River detected a significant decreasing historical trend in late winter snowmelt-driven floods, while the rainfall-driven spring and summer flood peaks exhibited no significant trend during the period of record. Unlike several previous studies which attribute the decline in flood peaks mainly to changes in land management, we hypothesize that climate change had a significant contribution to the overall decrease in flood peaks. In particular, we hypothesize that the increase in winter temperatures caused the decrease in snow depth, which in turn resulted in a decreasing trend in flood peaks. In an attempt to validate this hypothesis, we used long-term daily precipitation, temperature, and river flow data observed in the watershed as inputs to the Variable Infiltration Capacity (VIC) model to generate other non-monitored climatic variables. Trends in these climatic variables were then related to the trend in flood peaks in the Pecatonica River. Due to the complexity of the hydrologic system and numerous data and modeling-related uncertainties, the above hypothesis cannot be validated with certainty. Nonetheless, the results in two different modes (event and continuous simulation) provide support to the speculation that the decreasing trend in flood peaks was a result of decreasing snow depth. The model runs resulted in a decrease in snow depths for the period of record (1915–2009), increase in sublimation and evaporation, no change in base flow, and mixed results in infiltration. These analyses also suggest that VIC can be used in other similar regions in snowmelt-driven flood peak studies. It should be recognized, however, that the success of these applications can be severely constrained by various uncertainties, including but not limited to, the poor quality or absence of snow depth data.





  • Marshall, Charla; Kaestle, Frederika A. writer Marshall, Charla; Kaestle, Frederika A. by Marshall, Charla; Kaestle, Frederika A. published by Marshall, Charla; Kaestle, Frederika A.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2013
    (AN 92620217)
    America: History & Life
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  • Publication date: September 2014
    Source:Cretaceous Research, Volume 51

    Author(s): Yosmel Sanchez-Hernandez , Florentin J.-M.R. Maurrasse , Mihaela C. Melinte-Dobrinescu , Ding He , Shane K. Butler

    The Organyà Basin, south–central Spanish Pyrenees, developed as a marginal depocenter during a rapid extensional phase of anticlockwise rotation of the Iberian plate. As a result of increased subsidence, an important change in sedimentation occurred from the late Barremian to the Aptian leading to unusually high sediment accumulation rates. Approximately 1000 m of hemipelagic marls and limestones accumulated during this time interval. Here we studied the basal 85 m of the hemipelagic facies of the El Pui section, Organyà Basin, that are characterized by alternating 15 cm – ∼3 m thick beds of limestone and marls. Geochemical analyses indicate high total inorganic carbon (TIC) values (average 70%) suggesting enhanced CaCO3 production and deposition. SEM analyses of the samples indicate high abundance of calcareous nannofossils, which together with the absence of shallow water taxa characteristic of the Urgonian Carbonate platform of Organyà, and the lack of sedimentary facies attributable to carbonate platform components point to nannofossils as the main source for the elevated TIC. Organic-rich levels (total organic carbon (TOC) up to 1.74%) concurrent with positive excursions up to 2‰ in δ13Corg, imply enhanced preservation of organic matter (OM) in the basin. In addition, pronounced peaks of δ13Corg higher than the global average suggest superimposed local factors related to intensified 12C removal due to primary productivity. Biomarker analyses and the δ13Corg profile suggest an autochthonous origin of the OM from phytoplankton and possible additional contributions from microbial communities. X-ray diffraction (XRD) results attest for sustained terrestrial fluxes as the source of nutrients to the basin because of a 30% average non-carbonate bulk mineral content in the sediment. The non-carbonate fraction is dominated by quartz (average, 14%) whereas the clay mineral assemblages are characterized by high illite content (>73 relative%) with minor concentrations of kaolinite (<5%), illite /smectite mixed layers (<17%) and chlorite (<15%), consistent with a provenance from the Paleozoic metamorphic terranes adjacent to the Organyà Basin. The integrated results suggest a high sediment accumulation rate (5 cm/ky–7.5 cm/ky) and enhanced carbon burial during the latest Barremian–earliest Aptian in the hemipelagic setting of the El Pui section.





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  • Kozuch, Laura writer Kozuch, Laura by Kozuch, Laura published by Kozuch, Laura
    Southeastern Archaeology; 07/01/2013
    (AN 89690048)
    America: History & Life
  • Mazrim, Robert F.; Walthall, John A. writer Mazrim, Robert F.; Walthall, John A. by Mazrim, Robert F.; Walthall, John A. published by Mazrim, Robert F.; Walthall, John A.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2012
    (AN 85351845)
    America: History & Life
  • 7/5/2015
  • Publication date: 2015
    Source:Thorp and Covich's Freshwater Invertebrates

    Author(s): Kevin S. Cummings , Daniel L. Graf

    Two native groups represent the freshwater bivalves of North America: the freshwater mussels (Unionoidea) and the pill, fingernail, and pea clams (Sphaeriidae). There are also two widely publicized invasive genera, Corbicula and Dreissena. These mollusks have interesting and important ecological interactions with their environments, not the least of which is their relationship to humans. The bias of this chapter is toward the freshwater mussels. They are the numerically dominant group, with 10 times more species, and considerably more data are available on them. This chapter covers general biology, including internal and external anatomy, physiology, and reproduction. General ecology is discussed, including life-cycles, age and growth, and biotic interactions. The role of freshwater biovalves as biomonitors is reviewed.





  • Publication date: 2015
    Source:Thorp and Covich's Freshwater Invertebrates

    Author(s): R. Edward DeWalt , Boris C. Kondratieff , John B. Sandberg

    Plecoptera, or stoneflies, are an ancient insect order. The order name refers to the ability to fold their wings horizontally. Sixteen extant families and nearly 3,500 valid species are currently known. The nymphs of the vast majority of species are aquatic and most feed in two general categories, as shredders of leaves and as predators of other invertebrates. Adults are terrestrial, inhabiting vegetation near the stream or lake from which they emerged. In this chapter we present the morphology of stoneflies and cover aspects of their ecology and behavior. We also discuss sampling, rearing, and preservation of stonefly specimens. The conservation status of stoneflies is also discussed.





  • Publication date: 6 September 2014
    Source:Chemical Engineering Science, Volume 116

    Author(s): Xinhuai Ye , Yongqi Lu

    The enzyme carbonic anhydrase (CA) has potential as an efficient biocatalyst to promote the absorption of CO2 into potassium carbonate–bicarbonate (K2CO3–KHCO3) solutions for CO2 capture from the flue gas of coal-fired power plants. Knowing the kinetics of the promoted absorption and the catalytic activity and stability of CA under typical operating conditions is essential for process design and techno-economic analysis. In this study, we investigated two specifically engineered CA enzymes and experimentally determined the first-order rate constant of CA (k CA) for catalyzing CO2 hydration into K2CO3–KHCO3 solutions by measuring the rate of CO2 absorption into the solutions in a stirred cell reactor and using the classic Danckwerts theory for data interpretation. The k CA values obtained were 4.02 L mg 1 s 1 ( 1.21 × 10 8 M 1 s 1 ) at 25°C, 4.25 L mg 1 s 1 ( 1.28 × 10 8 M 1 s 1 ) at 40°C, and 4.07 L mg 1 s 1 ( 1.22 × 10 8 M 1 s 1 ) at 50°C. These values are applicable in 20wt% K2CO3–KHCO3 solutions with CO2 loadings ranging from 10 to 40% carbonate-to-bicarbonate (CTB) conversion. The k CA value did not substantially depend on the reaction temperatures at 25–50°C, the composition of the 20wt% K2CO3–KHCO3 solutions with 10–40% CTB conversion, or the pH condition (10.1 to 11.0 pH). The rate of CO2 absorption was promoted by two to six times in the presence of 300 mg L 1 of CA in 20wt% K2CO3–KHCO3 solutions at 40–60°C. The long-term thermal stability of CA was investigated at 40, 50, and 60°C in 20wt% K2CO3–KHCO3 solutions with 20 and 40% CTB conversion. The activity loss of CA, as indicated by a decrease in the enhancement factor (E CA) over time, was approximately 20% of its initial activity after 6 months at 40°C, was 50% after 2 months and 80% after 4 months at 50°C, and was 60% after 1 month and 80% after 2 months at 60°C. The CA showed comparable thermal stability in solutions with 20 and 40% CTB conversion, indicating that the CO2 loading of the solution was not an important factor in the thermal stability of the enzyme. The resistance of CA to flue gas impurities that may be transformed in the solvent, which are present in the form of SO 4 2 , NO 3 , and Cl anions was examined at 50°C in the 20wt% solution with 20% CTB conversion in the presence of 0.4M K2SO4, 0.3M KCl, and 0.05M KNO3, either alone or in combination. The CA did not show any further appreciable loss of activity or long-term stability in the presence of the simulated impurities at the concentrations investigated. The results of this study provide valuable information and practical guidance for the potential application of CA as a biocatalyst to promote the absorption of CO2 into K2CO3–KHCO3 solutions for CO2 capture.





  • Publication date: February 2015
    Source:Journal of Invertebrate Pathology, Volume 125

    Author(s): Meghan O. Milbrath , Toan van Tran , Wei-Fong Huang , Leellen F. Solter , David R. Tarpy , Frank Lawrence , Zachary Y. Huang

    Honey bees (Apis mellifera) are infected by two species of microsporidia: Nosema apis and Nosema ceranae. Epidemiological evidence indicates that N. ceranae may be replacing N. apis globally in A. mellifera populations, suggesting a potential competitive advantage of N. ceranae. Mixed infections of the two species occur, and little is known about the interactions among the host and the two pathogens that have allowed N. ceranae to become dominant in most geographical areas. We demonstrated that mixed Nosema species infections negatively affected honey bee survival (median survival=15–17days) more than single species infections (median survival=21days and 20days for N. apis and N. ceranae, respectively), with median survival of control bees of 27days. We found similar rates of infection (percentage of bees with active infections after inoculation) for both species in mixed infections, with N. apis having a slightly higher rate (91% compared to 86% for N. ceranae). We observed slightly higher spore counts in bees infected with N. ceranae than in bees infected with N. apis in single microsporidia infections, especially at the midpoint of infection (day 10). Bees with mixed infections of both species had higher spore counts than bees with single infections, but spore counts in mixed infections were highly variable. We did not see a competitive advantage for N. ceranae in mixed infections; N. apis spore counts were either higher or counts were similar for both species and more N. apis spores were produced in 62% of bees inoculated with equal dosages of the two microsporidian species. N. ceranae does not, therefore, appear to have a strong within-host advantage for either infectivity or spore growth, suggesting that direct competition in these worker bee mid-guts is not responsible for its apparent replacement of N. apis.

    Graphical abstract

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  • Publication date: June 2014
    Source:Journal of Applied Geophysics, Volume 105

    Author(s): Ahmed Ismail , F. Brett Denny , Mohamed Metwaly

    We use the seismic shear-wave reflection and multichannel analysis of surface wave (MASW) methods to examine if the MASW profiling can be an alternative for the shear-wave reflection method for near-surface characterization at specific subsurface settings. The shear wave reflection method does not work well in noisy areas, takes longer time for data acquisition and requires excessive post acquisition processing compared to the MASW method. Two surveys were conducted using land streamer technology along two lines totaling 3.7km in southern Illinois. The reflection data were used to generate seismic reflection profiles. The stacking velocities along the reflection profiles were converted into interval velocities and mapped as 2D velocity images. The MASW data were used to generate continuous 2D shear-wave velocity (Vs ) profiles. The MASW and the stacking-derived interval velocity images provided a smeared image of the overlying sedimentary layers and did not image small-scale features, such as igneous intrusions and near-surface faults. However, the MASW 2D Vs profiles and the reflection profiles compared well in mapping the bedrock surface and the thickness of the overlying unconsolidated sediment. The results confirmed that the MASW method can be an alternative to the reflection method when the survey target and near-surface conditions allow.





  • Publication date: May 2015
    Source:Mycoscience, Volume 56, Issue 3

    Author(s): Steven E. Zelski , Huzefa A. Raja , Andrew N. Miller , Carol A. Shearer

    A new species, Conioscypha peruviana was isolated from submerged woody debris collected in streams, rivers and a swamp in Peru. The anamorph formed in culture and morphological and molecular data support the inclusion in the genus. A phylogeny generated with maximum likelihood and Bayesian approaches placed the fungus in a well-supported clade with other Conioscypha and Conioscyphascus species. Nomenclature used herein reflects changes made in the Melbourne Code, with Conioscyphascus being considered a later synonym of Conioscypha. The fungus is described, illustrated and compared to morphologically similar taxa. In addition, Conioscypha gracilis comb. nov. is identified from both lentic and lotic habitats in Peru.





  • Mazrim, Robert writer Mazrim, Robert by Mazrim, Robert published by Mazrim, Robert
    International Journal of Historical Archaeology; 12/01/2013
    (AN 90632189)
    America: History & Life
  • 7/5/2015
  • Publication date: March 2015
    Source:Quaternary Research, Volume 83, Issue 2

    Author(s): Steven L. Voelker , Michael C. Stambaugh , Richard P. Guyette , Xiahong Feng , David A. Grimley , Steven W. Leavitt , Irina Panyushkina , Eric C. Grimm , Jeremiah P. Marsicek , Bryan Shuman , B. Brandon Curry

    During the last deglaciation temperatures over midcontinental North America warmed dramatically through the Bølling-Allerød, underwent a cool period associated with the Younger-Dryas and then reverted to warmer, near modern temperatures during the early Holocene. However, paleo proxy records of the hydroclimate of this period have presented divergent evidence. We reconstruct summer relative humidity (RH) across the last deglacial period using a mechanistic model of cellulose and leaf water δ18O and δD combined with a pollen-based temperature proxy to interpret stable isotopes of sub-fossil wood. Midcontinental RH was similar to modern conditions during the Last Glacial Maximum, progressively increased during the Bølling-Allerød, peaked during the Younger-Dryas, and declined sharply during the early Holocene. This RH record suggests deglacial summers were cooler and characterized by greater advection of moisture-laden air-masses from the Gulf of Mexico and subsequent entrainment over the mid-continent by a high-pressure system over the Laurentide ice sheet. These patterns help explain the formation of dark-colored cumulic horizons in many Great Plains paleosol sequences and the development of no-analog vegetation types common to the Midwest during the last deglacial period. Likewise, reduced early Holocene RH and precipitation correspond with a diminished glacial high-pressure system during the latter stages of ice-sheet collapse.





  • Publication date: 15 March 2014
    Source:Geomorphology, Volume 209

    Author(s): Andrew J. Stumpf , Travis Ferbey , Alain Plouffe , John J. Clague , Brent C. Ward , Roger C. Paulen , Andrew B.G. Bush

    McClenagan (2013) presents a model to explain streamlined erosional residuals or drumlins on uplands and lowlands in the plateau region of central British Columbia, Canada. In this discussion paper, we note that McClenagan (2013) has not adequately discussed previous relevant work in the region, and we argue that additional analyses and evidence are required to substantiate this new model. The hypothesis offered for the origin of the plateau landscape, specifically catastrophic glaciofluvial activity, differs significantly from a model based on glacial erosion and deformation that has been developed from field-based research over the past six decades. We discuss four critical points relating to the proposed model: (1) the current geological model for the plateau region of central British Columbia; (2) theory of glacial dispersal; (3) existing hypotheses for the formation of drumlins and other glacial landforms; and (4) theoretical glacial erosion modeling. We further suggest that the model cannot be substantiated without sedimentological or morphological field evidence for water bodies argued to be the source of the proposed megaflood or megafloods.





  • Publication date: 15 August 2014
    Source:Chemical Engineering Journal, Volume 250

    Author(s): Ling Zhao , Wei Zheng , Xinde Cao

    This study investigated the distribution and evolution of organic phases during biochar formation from twelve waste biomass and at the highest heating temperatures between 200°C and 650°C. Relation of the organic phase transformation to the carbon loss and pore structure was also analyzed. The organic phases in both feedstock biomass and the derived biochar were sequentially separated into four fractions: neutral detergent soluble fraction, hemicellulose, cellulose, and lignin. Plant-based residues mainly contained cellulose (25.8–64.6%), while municipal solid wastes had a large fraction of neutral detergent soluble fraction (22.9–65.0%). Transformation of cellulose into detergent soluble fraction and hemicellulose initially happened at the charring temperature between 100°C and 200°C, and the complete transformation was observed at the higher temperatures from 200°C to 350°C. The high lignin amount in biochar may be partly formed from the aromatization of cellulose fraction in addition to the contribution from the existing lignin in feedstock. All biochars had small total pore volumes ranging from 0.009cm3 g−1 to 0.278cm3 g−1 and were a type of mesoporous material with the pore sizes between 2nm and 30nm. The decrease of detergent soluble fraction, hemicellulose, and cellulose fractions had little effect on pore formation, but it was positively related to the C loss during pyrolysis. Pore volume and surface area seemed to have a positive relationship with lignin percentage and insoluble minerals in feedstock. This study provided insight into the mechanism of biochar formation related to the C loss and pore structure evolution. It will help produce the designated biochar with different environmental functions.





  • Publication date: Available online 6 April 2015
    Source:Journal of Great Lakes Research

    Author(s): Michael J. Weber , Blake C. Ruebush , Sara M. Creque , Rebecca A. Redman , Sergiusz J. Czesny , David H. Wahl , John M. Dettmers

    Recruitment of fishes is difficult to predict due to inter-annual and system variation. For example, the early life history of fishes inhabiting expansive freshwater systems such as the Great Lakes differs from other freshwater environments but has received less attention. Alewife Alosa pseudoharengus, an anadromous species adapted to living exclusively in freshwater, provides an opportunity to evaluate processes regulating growth and survival of a fish with marine origins inhabiting a large freshwater system. We collected age-0 alewives at three distinct locations (nearshore Chicago, nearshore Waukegan, offshore) in southwestern Lake Michigan during 2005 and 2006 to estimate density, growth, and survival. Larval alewife densities were up to three times greater and hatching peaks occurred earlier in 2005 compared to 2006. Back-calculated alewife hatch dates indicated that peak hatch occurred two weeks prior to peak catch rates, with similar hatching distributions of larvae collected between nearshore and offshore environments. Alewives up to approximately 16 d of age were collected in both nearshore locations before appearing in the offshore environment. Alewife growth rates were influenced by zooplankton density, water temperature, and hatching date whereas survival from the nearshore to offshore environment was influenced by wind events and hatching date. Prey availability and passive larval transport driven by offshore wind events are more commonly identified as factors influencing marine rather than freshwater larvae. Thus, factors affecting recruitment dynamics of fishes in large complex inland systems may be more similar to marine than freshwater systems.





  • Publication date: August 2015
    Source:Geoderma, Volumes 251–252

    Author(s): Sarah L. O'Brien , Julie D. Jastrow , David A. Grimley , Miquel A. Gonzalez-Meler

    Cultivation of undisturbed soils dramatically depletes organic carbon stocks at shallow depths, releasing a substantial quantity of stored carbon to the atmosphere. Restoration of native ecosystems can help degraded soils rebuild a portion of the depleted soil organic matter. However, the rate and magnitude of soil carbon accrual can be highly variable from site to site. Thus, a better understanding of the mechanisms controlling soil organic carbon stocks is necessary to improve predictions of soil carbon recovery. We measured soil organic carbon stocks and a suite of edaphic factors in the upper 10cm of a series of restored tallgrass prairies representing a range of drainage conditions. Our findings suggest that factors related to soil organic matter stabilization mechanisms (texture, polyvalent cations) were key predictors of soil organic carbon, along with variables that influence plant and microbial biomass (available phosphorus, pH) and soil moisture. Exchangeable soil calcium was the strongest single predictor, explaining 74% of the variation in soil organic carbon, followed by clay content, which explained 52% of the variation. Our results demonstrate that the cumulative effects of even relatively small differences in these edaphic properties can have a large impact on soil carbon stocks when integrated over several decades.





  • Publication date: March 2015
    Source:Environmental Pollution, Volume 198

    Author(s): Laurel K. Dodgen , Aiko Ueda , Xiaoqin Wu , David R. Parker , Jay Gan

    The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common.

    Graphical abstract

    image

    Teaser

    High plant transpiration in arid and hot areas may lead to increased foliar accumulation of PPCP/EDCs from treated wastewater irrigation.



  • Publication date: June 2014
    Source:Chemosphere, Volume 104

    Author(s): Jeffrey M. Levengood , David J. Soucek , Gregory G. Sass , Amy Dickinson , John M. Epifanio

    Efforts to control invasive bighead (Hypophthalmichthys nobilis) and silver carp (H. molitrix) may include harvest for human consumption. We measured concentrations of arsenic (As), mercury (Hg), and selenium (Se) in fillets from silver and bighead carp collected from the lower Illinois River, Illinois, USA, to determine whether concentrations were of health concern and differed by species, size, and location. Concentrations of total As were below detection limits in most bighead (92%) and silver (77%) carp fillets, whereas inorganic As was below detection limits in all samples. Mean Hg concentrations were greater in bighead (0.068mgkg−1) than in silver carp (0.035mgkg−1), and were smallest in carp from the confluence of the Illinois and Mississippi rivers. Mercury concentrations in fillets were positively correlated with body mass in both species. Concentrations of Hg were below the US Food and Drug Administration’s (USFDA) action level (1ppm as methyl-Hg); however, concentrations in some bighead (70%) and silver (12%) carp fell within the range that would invoke a recommendation to limit meals in sensitive cohorts. Mean Se concentrations were greater in silver (0.332mgkg−1) than in bighead (0.281mgkg−1) carp fillets, and were below the 1.5mgkg−1 limit for an unrestricted number of meals/month. The mean molar ratio of Se:Hg in fillets was lower in bighead (14.0) than in silver (29.1) carp and was negatively correlated with mass in both species Concentrations of Hg in bighead and silver carp fillets should be considered when assessing the risks associated with the use of these species as a protein source.





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  • Fishel, Richard L. writer Fishel, Richard L. by Fishel, Richard L. published by Fishel, Richard L.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2012
    (AN 85351847)
    America: History & Life
  • Publication date: November 2014
    Source:Chemosphere, Volume 114

    Author(s): Yonghong Zou , Erik R. Christensen , Wei Zheng , Hua Wei , An Li

    A stochastic process was developed to simulate the stepwise debromination pathways for polybrominated diphenyl ethers (PBDEs). The stochastic process uses an analogue Markov Chain Monte Carlo (AMCMC) algorithm to generate PBDE debromination profiles. The acceptance or rejection of the randomly drawn stepwise debromination reactions was determined by a maximum likelihood function. The experimental observations at certain time points were used as target profiles; therefore, the stochastic processes are capable of presenting the effects of reaction conditions on the selection of debromination pathways. The application of the model is illustrated by adopting the experimental results of decabromodiphenyl ether (BDE209) in hexane exposed to sunlight. Inferences that were not obvious from experimental data were suggested by model simulations. For example, BDE206 has much higher accumulation at the first 30min of sunlight exposure. By contrast, model simulation suggests that, BDE206 and BDE207 had comparable yields from BDE209. The reason for the higher BDE206 level is that BDE207 has the highest depletion in producing octa products. Compared to a previous version of the stochastic model based on stochastic reaction sequences (SRS), the AMCMC approach was determined to be more efficient and robust. Due to the feature of only requiring experimental observations as input, the AMCMC model is expected to be applicable to a wide range of PBDE debromination processes, e.g. microbial, photolytic, or joint effects in natural environments.





  • Marshall, Joel Michael; Krus, Anthony Michal writer Marshall, Joel Michael; Krus, Anthony Michal by Marshall, Joel Michael; Krus, Anthony Michal published by Marshall, Joel Michael; Krus, Anthony Michal
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2013
    (AN 92620212)
    America: History & Life
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  • Publication date: April 2014
    Source:Environmental Science & Policy, Volume 38

    Author(s): Tamara F. Blett , Jason A. Lynch , Linda H. Pardo , Cindy Huber , Richard Haeuber , Richard Pouyat

    The development and use of critical loads of air pollutant deposition in the U.S. is gaining momentum, and recent research efforts in the U.S. have produced valuable data for calculating critical loads. Critical loads are used to quantify the levels of air pollutants that are expected to impact forest health, soil fertility, aquatic biota condition, and other ecosystem responses. In addition, model refinements for improving critical loads estimates, and maps for illustrating critical loads for acidification and nitrogen saturation and eutrophication resulting from excess nutrient nitrogen, have been developed at various scales. However, prior to the effort described here, no cohesive process existed to provide a national-scale critical loads database and maps as a unified product representing all U.S. ecosystems. The FOCUS (Focal Center Utility Study) Project was initiated to coordinate the development and implementation of a clear, consistent, repeatable process for calculating and mapping critical loads within the U.S. In the FOCUS Phase I Pilot Study, empirical and calculated critical loads data for the U.S. were synthesized from dozens of regional and national-scale monitoring networks, research projects and publically available databases following an approach similar to that used in Europe. The United Nations Economic Commission for Europe (UNECE), through its International Cooperative Programme on Modelling and Mapping of Critical Levels & Loads and Air Pollution Effects, Risks and Trends (ICP-M&M) collects, analyzes and maps critical loads data. Countries participating in the Convention on Long-range Transboundary Air Pollution (CLRTAP) use a Critical Loads “Focal Center” in each country to serve as the point of contact for submitting regional and national-scale critical loads data to the ICP-M&M. One of the purposes of this study was to develop a foundation for interacting with other Focal Centers by assembling critical loads data, creating a database, establishing modeling protocols, and developing infrastructure within the U.S to report and update critical loads on a national scale. Because the U.S. does not currently have an officially designated Focal Center, critical loads data were provided as an informal, unofficial submission to the Coordination Center for Effects (CCE) of the ICP-M&M in March 2011, in the interest of international cooperation and exchange of information on the effects of atmospheric deposition of pollutants on ecosystems. We envision that these data will enable U.S. scientists, land managers, and environmental policymakers to enter into a productive and meaningful dialogue within the US, and also with the international scientific community on methods for estimating, calculating, mapping, interpreting, and refining critical loads for the effects of acidification and excess nutrient nitrogen on terrestrial and aquatic ecosystems. This paper describes the process used to develop national-scale critical loads in the U.S., summarizes the FOCUS Phase I approach and database development effort, and presents some initial national-scale critical loads mapping products.





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  • Publication date: 15 August 2014
    Source:Geomorphology, Volume 219

    Author(s): William L. Blewett , Scott A. Drzyzga , Laura Sherrod , Hong Wang

    Data obtained from ground-penetrating radar (GPR), optically stimulated luminescence (OSL) dating, and geostatistical reconstructions of Lake Algonquin water planes indicate that high-standing outwash aprons flanking the Munising moraine's southern margin in eastern Upper Michigan terminate as large, coalescing Gilbert-type ice-contact deltas graded to the Main level of Lake Algonquin. Nearly 30km of GPR imagery provides clear evidence of topset and foreset beds diagnostic of deltaic deposition. Landform assemblages suggest that the deltas likely evolved from subaqueous grounding line fans formed along a retreating ice margin characterized by widespread stagnation. In time, these deltas aggraded to the Main Lake Algonquin level as the ice margin stabilized. An OSL date of 12.5±1.1ka on a nearby beach ridge associated with the Main Algonquin shoreline is consistent with this interpretation. These new data, coupled with the presence of nested fans at the downstream end of meltwater channels incised into the delta, indicate that Lake Algonquin was falling as delta deposition waned, eventually reaching a level concordant with the Lower Orillia level before final abandonment. Large, regionally extensive heads of outwash marking the crest of the Munising moraine are graded to the upper margins of these deltas and, by inference, must also correlate with Main Lake Algonquin and the associated Two Rivers deglaciation ca. 13–12.5ka. The deltas, in turn, are conspicuously crosscut by outwash aprons that are graded to levels much lower than any recognized upper group Lake Algonquin shoreline. Because these aforementioned heads of outwash, part of Drexler and others' Grand Marais moraine, correlate with the Marquette moraine farther west, they likely date to the Marquette advance ca. 11.5ka. Thus, landforms related to Two Rivers and to Marquette glaciations appear to comingle across the study area. In the absence of extensive exposures and datable materials, our work highlights the fact that crosscutting relationships and distinct differences in base level can provide an important first step for untangling the complicated landform relationships in this part of Michigan.





  • Publication date: January 2015
    Source:Cretaceous Research, Volume 52, Part B

    Author(s): Nathan Barling , David M. Martill , Sam W. Heads , Florence Gallien

    Fossil insects from the Lower Cretaceous (Aptian) Crato Formation of north-east Brazil are preserved as goethite replacements in laminated limestones of lacustro-lagoonal origin. They display remarkable degrees of morphological detail down to the macromolecular level in some examples. We document the fidelity of preservation and reveal an astonishing variety of morphological detail comparable in some instances with that found in amber inclusions.





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  • Publication date: April 2014
    Source:Journal of Archaeological Science, Volume 44

    Author(s): Philip A. Slater , Kristin M. Hedman , Thomas E. Emerson

    Archaeologists have long debated the role of regional interaction in the 11th to 14th centuries at the Mississippian polity of Cahokia. Architectural styles, exotic materials, and cultural objects provide indirect evidence for cultural interaction and ethnic and social diversity; however, identifying the movement of individuals (rather than materials) is key to our growing understanding of the population history that enabled the formation of this unique polity. This study is the first to use strontium isotope analysis (87Sr/86Sr) of human tooth enamel to identify immigrants at Cahokia. Modern and archaeological fauna were used to establish a baseline “local” range of strontium isotope ratios for the American Bottom region surrounding Cahokia. Teeth from individuals interred in diverse mortuary locations, including mounds, within this region were analyzed and compared to the local strontium isotope range to identify individuals of non-local origin. One-third of all individuals analyzed were identified as non-local, and the range and variability of their strontium ratios suggests multiple places of origin. The correlation of isotopic data with available biological and mortuary evidence allows us to examine the role of migration in the history of this Mississippian polity.





  • Publication date: January 2015
    Source:Journal of Invertebrate Pathology, Volume 124

    Author(s): Wei-Fone Huang , Leellen Solter , Katherine Aronstein , Zachary Huang

    Nosema ceranae infection is ubiquitous in western honey bees, Apis mellifera, in the United States and the pathogen has apparently replaced Nosema apis in colonies nationwide. Displacement of N. apis suggests that N. ceranae has competitive advantages but N. ceranae was significantly less infective and less virulent than N. apis in commercially available lineages of honey bees in studies conducted in Illinois and Texas. At 5days post eclosion, the most susceptible age of adult bees tested, the mean ID50 for N. apis was 359 spores compared to 3217 N. ceranae spores, a nearly 9-fold difference. Infectivity of N. ceranae was also lower than N. apis for 24-h and 14-day worker bees. N. ceranae was less infective than reported in studies using European strains of honey bees, while N. apis infectivity, tested in the same cohort of honey bees, corresponded to results reported globally from 1972 to 2010. Mortality of worker bees was similar for both pathogens at a dosage of 50 spores and was not different from the uninfected controls, but was significantly higher for N. apis than N. ceranae at dosages ⩾500 spores. Our results provide comparisons for evaluating research using different ages of bees and pathogen dosages and clarify some controversies. In addition, comparisons among studies suggest that the mixed lineages of US honey bees may be less susceptible to N. ceranae infections than are European bees or that the US isolates of the pathogen are less infective and less virulent than European isolates.

    Graphical abstract

    image




  • Publication date: January 2015
    Source:Atmospheric Environment, Volume 101

    Author(s): Marcelo S. Vieira-Filho , Christopher Lehmann , Adalgiza Fornaro

    Wet deposition was measured in two urban areas of Brazil, Cubatão and São Paulo megacity (MASP), from July 2009 to August 2010. Cubatão is characterized by the large and complex industrial sector and MASP by a large vehicular fleet, and these different sources contributed to 15.5 × 106 and 25.5 × 106 kg year−1 of SO2 air emissions, respectively. The rainwater volume-weighted mean (VWM) pH values and [SO4 2−] in Cubatão and in MASP were 4.8 and 7.1 μmol L−1, and 5.3 and 24.5 μmol L−1, respectively. Regarding nitrogen content, the difference between reduced and oxidized nitrogen was more pronounced in MASP, where more than 61% of total nitrogen scavenged as NH4 +. The wet-only sulfur deposition in Cubatão was 17.0 kg Sha−1 y−1, which was 2.7-fold higher than that in MASP. Although the higher air pollutant emissions occur in MASP, the worst air quality and wet deposition has been observed in Cubatão due to the orographic conditions.





  • Publication date: December 2014
    Source:Journal of Great Lakes Research, Volume 40, Issue 4

    Author(s): Greg G. Sass , Collin Hinz , Anthony C. Erickson , Nerissa N. McClelland , Michael A. McClelland , John M. Epifanio

    Aquatic invasive species introductions are a global environmental concern. Negative effects of invasive species are often manifested in alterations of food web structure and through competition with and predation upon native species. The Illinois River, Illinois, USA harbors invasive, planktivorous bighead, Hypophthalmichthys nobilis, and silver carp, Hypophthalmichthys molitrix, and can be a model ecosystem to test for their effects on zooplankton communities. We tested for bighead and silver carp effects on zooplankton communities pre- and post-establishment within one reach of the Illinois River and among river reaches that varied in abundances of these invasive fishes. The establishment of bighead and silver carp was associated with increased rotifer abundances, while cladoceran and copepod abundances were reduced relative to pre-establishment. Cladoceran and copepod abundance and biomass were negatively associated with bighead and silver carp abundances among reaches. Total zooplankton and rotifer abundance and biomass were positively associated with bighead and silver carp abundances. Our results suggest that bighead and silver carp have changed the zooplankton community of the Illinois River which may have implications for the food web, native species, and other ecosystems poised to be invaded, such as the Laurentian Great Lakes.





  • Publication date: January 2015
    Source:Chemical Engineering Research and Design, Volume 93

    Author(s): Qing Ye , Xinlei Wang , Yongqi Lu

    A carbonate-based CO2 absorption process is currently under development that involves crystallizing potassium bicarbonate from a potassium carbonate/bicarbonate solution to form slurry used for stripping CO2 at high pressure. Kinetics of the bicarbonate crystallization process was investigated using a laboratory mixed suspension, mixed product removal (MSMPR) reactor. Effects of the mean residence time, agitation speed, relative supersaturation level, crystallization temperature, and suspension density on nucleation and growth rates of the bicarbonate crystals were quantified. The observed crystal population density distribution featured a size-dependent growth pattern. A three-parameter kinetic model was used for bicarbonate crystallization, and model parameters were determined by fitting the experimental data. Crystallization kinetics was applied to perform a preliminary analysis of the crystallizer design for the carbonate-based CO2 capture process.





  • Publication date: 6 September 2014
    Source:Chemical Engineering Science, Volume 116

    Author(s): Xinhuai Ye , Yongqi Lu

    Potassium carbonate–bicarbonate (K2CO3–KHCO3) aqueous solutions could be used as an alternative to amines as solvents in CO2 capture from the flue gas of coal-fired power plants. The rate of CO2 absorption into K2CO3–KHCO3 solutions is governed by the reaction between CO2 and OH , which is first order with respect to both CO2 and [ OH ] ( r = k OH [ OH ] [ CO 2 ] ) . Knowledge of the reaction kinetics and dynamic changes in kinetics along an absorber is essential for process design. However, this information, particularly the values of the rate constant of the reaction between CO2 and OH , k OH , in K2CO3–KHCO3 solutions with different ionic strengths and CO2 loadings are seldom available in the literature. In this study, we investigated the kinetics of CO2 absorption into 5–40wt% solutions with different levels of CO2 loading at 25–80°C. The k OH values were determined by measuring rates of CO2 absorption into the solutions in a stirred cell reactor and by using the classic Danckwerts theory for interpretation of the data. The method was validated by the good agreement between the rate constants obtained for infinitely dilute solutions and those reported in the literature. The CO2 loading of K2CO3–KHCO3 solutions was found to govern the activation energy (E a ) of the absorption reaction. In K2CO3–KHCO3 solutions with the same CO2 loading, the E a values were comparable, regardless of the concentration or total ionic strength of the solution. The E a decreased as the CO2 loading of the solution increased. The ionic strength of the solution substantially affected the Arrhenius pre-exponential factor term [ln(A)] of k OH. Functional formulae have been developed that can be readily used to calculate k OH for K2CO3–KHCO3 solutions with different levels of CO2 loading over the applicable range. The results provide extensive information on the kinetics of the CO2 reaction in K2CO3–KHCO3 solutions, particularly in concentrated solutions (20–40wt%) with a CO2 loading up to 40% of potassium carbonate to bicarbonate conversion at temperatures up to 80°C.





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  • Publication date: April 2015
    Source:Global and Planetary Change, Volume 127

    Author(s): Bingjun Liu , Cuiliu Chen , Yanqing Lian , Junfan Chen , Xiaohong Chen

    Using the daily precipitation and temperature data at 153 stations in the karst area of Southwest China from 1959 to 2009, the long-term change characteristics of wet and dry climatic conditions are analyzed by the Mann–Kendall test. This study shows that: 1) the annual average temperature has increased at 88% of the stations with an average rate of +0.16°C/10-year. This increase rate is greater than +0.30°C/10-year in the southeastern, northeastern, and western parts of the study region. Very warm days and abnormally warm days were seen increased at 47% and 63% of the stations, respectively. Very cool days and abnormally cool days in a year have reduced at respectively 94% and 95% of the stations; 2) no clear change trend was found for average annual precipitation over the entire area as a whole, but regional and seasonal changes were quite obvious. The annual total precipitation has decreased by −22.5mm/10-year in the central part but increased by +8.9mm/10-year in the western part of the region, and summer and winter seemed to become wetter while spring and autumn became drier. Although the number of rainy days in a year has decreased at almost 53% of the total stations with an average rate of −3.9days/10-year over the entire area, the number of extremely heavy rainy days has increased by +0.2, +0.4 and +0.4days/10-year in the southern Sichuan Province, the central part of Yunnan Province, and the northeastern Hubei Province, respectively; and 3) the extreme drought became more serious. The consecutive dry days has increased significantly at nearly 46% of the stations, especially in the western Guangxi Autonomous Region, the southern Guizhou Province, and the eastern Chongqing Municipality. The extreme drought remained at a high frequency at the beginning of the 21st century. It has shifted gradually from the eastern and western parts to the south-central part which is characterized by medium-high rocky desertification. Hopefully findings from this study will help for a better understanding of the impacts to some eminent geological hazards such as rocky desertification, increased frequency of drought and storms, and landslides in recent years.





  • Publication date: 2015
    Source:Climate Risk Management, Volume 7

    Author(s): Tonya Haigh , Eugene Takle , Jeffrey Andresen , Melissa Widhalm , J. Stuart Carlton , Jim Angel

    The usefulness of climate information for agricultural risk management hinges on its availability and relevance to the producer when climate-sensitive decisions are being made. Climate information providers are challenged with the task of balancing forecast availability and lead time with acceptable forecast skill, which requires an improved understanding of the timing of agricultural decision making. Achieving a useful balance may also require an expansion of inquiry to include use of non-forecast climate information (i.e. historical climate information) in agricultural decision making. Decision calendars have proven valuable for identifying opportunities for using different types of climate information. The extent to which decision-making time periods are localized versus generalized across major commodity-producing regions is yet unknown, though, which has limited their use in climate product development. Based on a 2012 survey of more than 4770 agricultural producers across the U.S. Corn Belt region, we found variation in the timing of decision-making points in the crop year based on geographic variation as well as crop management differences. Many key decisions in the cropping year take place during the preceding fall and winter, months before planting, raising questions about types of climate information that might be best inserted into risk management decisions at that time. We found that historical climate information and long term climate outlooks are less influential in agricultural risk management than current weather, short term forecasts, or monthly climate projections, even though they may, in fact, be more useful to certain types of decision making.





  • Publication date: July–August 2014
    Source:Comptes Rendus Geoscience, Volume 346, Issues 7–8

    Author(s): C. Blaine Cecil , William A. DiMichele , Scott D. Elrick

    The Pennsylvanian portion of the Late Paleozoic Ice Age was characterized by stratigraphic repetition of chemical and siliciclastic rocks in the equatorial regions of the Pangean interior. Known as “cyclothems”, these stratigraphic successions are a 105 yr-record of glacial waxing and waning, superimposed on longer term, 106 yr intervals of global warming and cooling and a still longer term trend of increasing equatorial aridity. During periods of maximum ice–minimum sea level, the interior craton was widely exposed. Epicontinental landscapes were initially subjected to dry subhumid climate when first exposed, as sea level fell, but transitioned to humid climates and widespread wetlands during maximum lowstands. During interglacials (ice-minima) seasonally dry vegetation predominated. The wetland and seasonally dry biomes were compositionally distinct and had different ecological and evolutionary dynamics.





  • Publication date: 1 September 2014
    Source:Geomorphology, Volume 220

    Author(s): Kory Allred , Wei Luo , Mike Konen , B. Brandon Curry

    Ice-walled lake plains (IWLPs) are rounded, flat-topped mounds that formed in stagnant ice environments along the margins of the Laurentide Ice Sheet. We conducted detailed morphometric and statistical analyses of the shape, size, and orientation of more than 400 IWLPs identified from aerial photos aided with LiDAR data in DeKalb County, Illinois, USA. Lake elongation theories include extraterrestrial impact (e.g. the Carolina Bays), ice flow dynamics and crevasses, and wind induced currents that preferentially erode the shorelines perpendicular to the dominant wind direction. The results indicate that elliptical IWLPs with a perimeter greater than 3050m have preferred orientations roughly normal to the paleo-wind direction as indicated by contemporaneous parabolic dunes located 50km to the west. The orientations of the IWLPs with a perimeter less than 1220m are scattered and show no apparent trend. The IWLP orientation is not related to ice flow dynamics or glacial crevasses because no statistically significant relationship exists with regard to the ice flow as proxied by the moraine direction. The orientation of large IWLPs in DeKalb County are consistent with wind-induced lake elongation observed in modern permafrost thaw lakes, suggesting that the prevailing wind also played an important role in controlling the orientation of IWLPs during the last glacial period and led to the preferred orientation we see today.





  • Publication date: 19 March 2015
    Source:Quaternary International, Volume 362

    Author(s): L.M.A.L. Ribeiro , A.O. Sawakuchi , H. Wang , W. Sallun Filho , L. Nogueira

    Robust chronologies for Quaternary fluvial carbonate sediments (tufas) from Brazil are still challenging. We obtain Optically Stimulated Luminescence (OSL) ages of Brazilian tufa deposits using the Single Aliquot Regeneration (SAR) dose protocol applied to single grains and multigrain aliquots of quartz extracted from tufa matrix. Additionally, radiocarbon (14C) ages were obtained for the carbonate matrix and organic matter from tufas. The methodology was applied in samples from tufa deposits in southwestern and southeastern regions with Quaternary carbonate deposition. Equivalent doses distributions have overdispersion between 19% and 81%, indicating that the studied samples comprise well bleached as well as poorly bleached sediments. The quartz grains extracted from the studied tufas show an OSL signal dominated by the fast component and reliable dose response curves, with saturation doses (2D 0) ranging from 35 to 210 Gy. Most of the samples has low radiation dose rates (0.40 ± 0.02 to 0.78 ± 0.05 Gy/ka), with variation in the water content due to compaction and matrix recrystallization, being the major factors that could induce dose rate changes through time. Hard tufa samples with intense carbonate cementation show quartz OSL ages from 51.9 ± 4.8 to 150.3 ± 35.9 years. These ages are much older than the radiocarbon ages of the carbonate matrix and organic matter. The OSL ages of soft tufa samples related with the active fluvial system ranged from 0.8 ± 0.1 to 5.5 ± 0.4 years and are in the same interval of radiocarbon ages presented in the previous works. We interpret that carbonate recrystallization or uptake of organic matter after tufa formation are responsible for the younger radiocarbon ages compared to quartz OSL ages in the older tufa samples. For these samples, age differences vary up to tens of thousands years between deposition of quartz grains and the last episode of carbonate recrystallization or organic matter uptake. Consequently we believe that the obtained OSL ages are the best estimates for the starting deposition time of the studied tufa samples.





  • Publication date: 10 February 2015
    Source:Thermochimica Acta, Volume 601

    Author(s): Zengshe Liu , Brajendra K. Sharma , Sevim Z. Erhan , Atanu Biswas , Rongpeng Wang , Thomas P. Schuman

    Oxidation and low temperature stability of polymerized soybean oil (PSO)-based lubricants have been investigated by the pressurized differential scanning calorimetry (PDSC) method. It was found that PSO samples have lower oxidative stability than their precursor, soybean oil. The main reason for the decreased stability is the generation of tertiary carbons during polymerization. By using antioxidant additives, the PSO samples responded very well and increased their onset temperature (OT) by 70–80°C. Thermogravimetric analyses have been performed on the PSO samples and it was observed that they are thermally stable at temperatures up to 250°C. Cold flow property data shows that the PSO samples are good for use in formulating high temperature lubricants. Two model compounds which have terminal double bonds, triacyl-10-undecenoate and allyl 10-undecenoate, have been polymerized. The oxidation stability of these two compounds was investigated by the PDSC method and compared to that of the PSO samples. This study will help us understand the relationships between oxidation stability and molecular structure of PSO-based lubricants. In addition, oxidation stability data of polyethylene (PE) and polypropylene (PP) were used in helping to explain the oxidation stability results of the PSO samples.

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  • Publication date: 15 April 2015
    Source:Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 424

    Author(s): Larry F. Rinehart , Spencer G. Lucas , Lawrence Tanner , W. John Nelson , Scott D. Elrick , Dan S. Chaney , William A. DiMichele

    Natural molds of 165 stems were found in life position in a 1m-thick sandstone bed, lower Permian (Wolfcampian), Sangre de Cristo Formation, northern New Mexico. The sandstone represents a single flood event of a river sourced in the Ancestral Rocky Mountains. Most of the flood-buried plants survived and resumed growth. The stem affinities are uncertain, but they resemble coniferophytic gymnosperms, possibly dicranophylls. Stem diameters (N=135) vary from 1 to 21cm, with three strongly overlapping size classes. Modern forest studies predict a monotonically decreasing number (inverse square law) of individuals per size class as diameter increases. This is not seen for fossil stems ≤6cm diameter, reflecting biases against preservation, exposure, and observation of smaller individuals. Stems ≥6cm diameter obey the predicted inverse square law of diameter distribution. Height estimates calculated from diameter-to-height relationships of modern gymnosperms yielded heights varying from ~0.9m to >8m, mean of ~3m. Mean stand density is approximately 2 stems/m2 (20,000 stems/hectare) for all stems >1cm diameter. For stems >7.5cm or >10cm diameter, density is approximately 0.24 stems/m2 (2400 stems/hectare) and 0.14 stems/m2 (1400 stems/hectare). Stem spatial distribution is random (Poisson). Mean all-stem nearest-neighbor distance (NND) averages 36cm. Mean NND between stems >7.5cm and >10cm diameter is approximately 1.02m and 1.36m. NND increases in approximate isometry with stem diameter, indicating conformation to the same spatial packing rules found in extant forests and other fossil forests of varying ages. Nearest-neighbor distance distribution passes statistical testing for normality, but with positive skew, as often seen in extant NND distributions. The size-frequency distribution of the stems is similar to those of Jurassic, early Tertiary, and extant woodlands; the early Permian woodland distribution line has the same slope, but differs in that the overall size range increases over time (Cope's rule). The early Permian woodland is self-thinning; its volume versus density relationship shows a self-thinning exponent between −1.25 and −1.5, within the range seen in some extant plant stands (−1.21 to −1.7).





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  • Publication date: March 2015
    Source:Brain, Behavior, and Immunity, Volume 45

    Author(s): Loren Merrill , Jennifer L. Grindstaff

    Both maternal exposure to stressors and exposure of offspring to stressors during early life can have lifelong effects on the physiology and behavior of offspring. Stress exposure can permanently shape an individual’s phenotype by influencing the development of the hypothalamic–pituitary–adrenal (HPA) axis, which is responsible for the production and regulation of glucocorticoids such as corticosterone (CORT). In this study we used captive zebra finches (Taeniopygia guttata) to examine the effects of matching and mismatching maternal and early post-natal exposure to one of two types of antigens or a control on HPA axis reactivity in adult offspring. Prior to breeding, adult females were injected with lipopolysaccharide (LPS), keyhole limpet hemocyanin (KLH) or a control. Offspring of females in each of the three treatments were themselves exposed to LPS, KLH or a control injection at 5 and 28days post-hatch. When offspring were at least 18months of age, standardized capture and restraint stress tests were conducted to determine the impact of the treatments on adult stress responsiveness. We found significant interaction effects between maternal and offspring treatments on stress-induced CORT levels, and evidence in support of the environment matching hypothesis for KLH-treated birds, not LPS-treated birds. KLH-treated offspring of KLH-treated mothers exhibited reduced stress-induced CORT levels, whereas LPS-treated or control offspring of KLH-treated mothers exhibited elevated stress-induced CORT levels. Although the treatment effects on baseline CORT were non-significant, the overall pattern was similar to the effects observed on stress-induced CORT levels. Our results highlight the complex nature of HPA axis programming, and to our knowledge, provide the first evidence that a match or mismatch between pre and post-natal antigen exposure can have life-long consequences for HPA axis function.





  • Leow, Shijie; Witter, John R.; Vardon, Derek R.; et al. writer Leow, Shijie; Witter, John R.; Vardon, Derek R.; et al. by Leow, Shijie; Witter, John R.; Vardon, Derek R.; et al. published by Leow, Shijie; Witter, John R.; Vardon, Derek R.; et al.
    Title: Prediction of microalgae hydrothermal liquefaction products from feedstock biochemical composition
    Author(s): Leow, Shijie; Witter, John R.; Vardon, Derek R.; et al.
    Source: GREEN CHEMISTRY, 17 (6): 3584-3599 2015
    Document Type: Article
  • Nolan, David J.; Hickson, Robert N.; Kuehn, Steven R.; Branstner, Mark C. writer Nolan, David J.; Hickson, Robert N.; Kuehn, Steven R.; Branstner, Mark C. by Nolan, David J.; Hickson, Robert N.; Kuehn, Steven R.; Branstner, Mark C. published by Nolan, David J.; Hickson, Robert N.; Kuehn, Steven R.; Branstner, Mark C.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2012
    (AN 85351848)
    America: History & Life
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  • Publication date: June 2014
    Source:Fuel Processing Technology, Volume 122

    Author(s): Brajendra K. Sharma , Bryan R. Moser , Karl E. Vermillion , Kenneth M. Doll , Nandakishore Rajagopalan

    Pyrolysis of HDPE waste grocery bags followed by distillation resulted in a liquid hydrocarbon mixture with average structure consisting of saturated aliphatic paraffinic hydrogens (96.8%), aliphatic olefinic hydrogens (2.6%) and aromatic hydrogens (0.6%) that corresponded to the boiling range of conventional petroleum diesel fuel (#1 diesel 190–290°C and #2 diesel 290–340°C). Characterization of the liquid hydrocarbon mixture was accomplished with gas chromatography–mass spectroscopy, infrared and nuclear magnetic resonance spectroscopies, size exclusion chromatography, and simulated distillation. No oxygenated species such as carboxylic acids, aldehydes, ethers, ketones, or alcohols were detected. Comparison of the fuel properties to the petrodiesel fuel standards ASTM D975 and EN 590 revealed that the synthetic product was within all specifications after addition of antioxidants with the exception of density (802kg/m3). Notably, the derived cetane number (73.4) and lubricity (198μm, 60°C, ASTM D6890) represented significant enhancements over those of conventional petroleum diesel fuel. Other fuel properties included a kinematic viscosity (40°C) of 2.96mm2/s, cloud point of 4.7°C, flash point of 81.5°C, and energy content of 46.16MJ/kg. In summary, liquid hydrocarbons with appropriate boiling range produced from pyrolysis of waste plastic appear suitable as blend components for conventional petroleum diesel fuel.

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  • Publication date: March 2015
    Source:Aeolian Research, Volume 16

    Author(s): Jeffrey S. Pigati , John P. McGeehin , Daniel R. Muhs , David A. Grimley , Jeffrey C. Nekola

    Small terrestrial gastropod shells (mainly Succineidae) have been used successfully to date late Quaternary loess deposits in Alaska and the Great Plains. However, Succineidae shells are less common in loess deposits in the Mississippi Valley compared to those of the Polygyridae, Helicinidae, and Discidae families. In this study, we conducted several tests to determine whether shells of these gastropods could provide reliable ages for loess deposits in the Mississippi Valley. Our results show that most of the taxa that we investigated incorporate small amounts (1–5%) of old carbon from limestone in their shells, meaning that they should yield ages that are accurate to within a few hundred years. In contrast, shells of the genus Mesodon (Mesodon elevatus and Mesodon zaletus) contain significant and variable amounts of old carbon, yielding ages that are up to a couple thousand 14C years too old. Although terrestrial gastropod shells have tremendous potential for 14C dating loess deposits throughout North America, we acknowledge that accuracy to within a few hundred years may not be sufficient for those interested in developing high-resolution loess chronologies. Even with this limitation, however, 14C dating of terrestrial gastropod shells present in Mississippi Valley loess deposits may prove useful for researchers interested in processes that took place over multi-millennial timescales or in differentiating stratigraphic units that have significantly different ages but similar physical and geochemical properties. The results presented here may also be useful to researchers studying loess deposits outside North America that contain similar gastropod taxa.





  • Publication date: December 2014
    Source:Soil Biology and Biochemistry, Volume 79

    Author(s): Minjie Yao , Junpeng Rui , Jiabao Li , Yumei Dai , Yongfei Bai , Petr Heděnec , Junming Wang , Shiheng Zhang , Kequan Pei , Chi Liu , Yanfen Wang , Zhili He , Jan Frouz , Xiangzhen Li

    Serious nitrogen (N) deposition in terrestrial ecosystems causes soil acidification and changes the structure and function of the microbial community. However, it is unclear how these changes are dependent on N deposition rates, other factors induced by N (e.g., pH), and their interactions. In this study, we investigated the responses of soil prokaryotic community structure and stability after a 13-year N addition in the semi-arid Leymus chinensis steppe in Inner Mongolia, China. Our results demonstrated that the prokaryotic community structure changed at the low N addition rate of 1.75 g N m−2 yr−1; however, dramatic changes in microbial abundance, respiratory quotient, and prokaryotic diversity occurred at N addition rates of more than 5.25 g N m−2 yr−1 when the soil pH dropped below 6.0. The two patterns indicated the difference in driving forces for different microbial properties. The N-driven and pH-driven processes are likely the most important mechanisms determining the responses of bacterial community to N. Some copiotrophic/oligotrophic bacteria, e.g., Proteobacteria and Acidobacteria, changed their relative abundances with the N addition continuously even at a low rate, indicating that they were more sensitive to N directly. Some bacterial groups significantly changed their relative abundance at a high N addition rate when pH dropped below 6.0, e.g., Verrucomicrobia and Armatimonadetes, indicating that they were more sensitive to pH below 6.0. N addition altered the prokaryotic community structure through enrichment of copiotrophic bacteria (species adjustment) at low N addition rates and through enrichment of nitrophilous taxa and significant loss of diversity at high N rates. The results also demonstrated that a high N addition diminished the stability of the prokaryotic community structure and activity through reduction in species diversity and bacterial interaction. Overall, this study supported the hypothesis that the responses of prokaryota to N were dependent on deposition rates, and N-driven and pH-driven processes were the important mechanisms to control the shift of the prokaryotic community.





  • Mazrim, Robert F. writer Mazrim, Robert F. by Mazrim, Robert F. published by Mazrim, Robert F.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 04/01/2011
    (AN 65100783)
    America: History & Life
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  • Publication date: January 2015
    Source:Journal of Invertebrate Pathology, Volume 124

    Author(s): Daniela K. Pilarska , Renate Radek , Wei-Fong Huang , Danail I. Takov , Andreas Linde , Leellen F. Solter

    The historic genus Pleistophora (Plistophora) is a highly polyphyletic clade with invertebrate Microsporidia reassigned to several new genera since the 1980s. Two genera, Endoreticulatus and Cystosporogenes, clearly separate into distinct but closely related clades based on small subunit ribosomal RNA analysis but are included in different families that are each polyphyletic. A microsporidium with morphology resembling the Endoreticulatus/Cystosporogenes clade was isolated from the grasshopper Poecilimon thoracicus from a site in Northwest Bulgaria. It produced intense infections in the digestive tract of the host but no behavioral changes were noted in infected individuals. Prevalence of the microsporidium increased over the active feeding season yearly. Mature spores were oval and measured 2.58±0.21μm×1.34±0.24μm, with 16 to approximately 32 spores in a parasitophorous vacuole. The spores were uninucleate and polar filament coils numbered 8–9 situated in a single row. The spore polaroplast consisted of an anterior lamellar section and a posterior vesicular section, and the posterior vacuole was reduced. Analyses of a 1221bp partial SSU-rRNA sequence indicated that the isolate is more closely related to the Endoreticulatus clade than to Cystosporogenes, but shows earlier phylogenetic separation from species infecting Lepidoptera and represents a new species, Endoreticulatus poecilimonae. To compare sequences of Endoreticulatus spp. from Lepidoptera to those infecting other insect orders, an isolate, Microsporidium itiiti Malone (1985), described from the Argentine stem weevil, Listronotus bonariensis, was sequenced. Like the grasshopper isolate, the weevil isolate is closely related but basal to the lepidopteran Endoreticulatus clade. The original description combined with the new sequence data confirms species status and permits transfer of the isolate from Microsporidium, a genus erected for microsporidian species of uncertain taxonomic status, to Endoreticulatus.

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    Highlights






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  • Publication date: May 2014
    Source:Earth-Science Reviews, Volume 132

    Author(s): Zhongcheng Jiang , Yanqing Lian , Xiaoqun Qin

    Rocky desertification, which is relatively less well known than desertification, refers to the processes and human activities that transform a karst area covered by vegetation and soil into a rocky landscape. It has occurred in various countries and regions, including the European Mediterranean and Dinaric Karst regions of the Balkan Peninsula, Southwest China on a large scale, and alarmingly, even in tropical rainforests such as Haiti and Barbados, and has had tremendous negative impacts to the environment and social and economic conditions at local and regional scales. The goal of this paper is to provide a thorough review of the impacts, causes, and restoration measures of rocky desertification based on decades of studies in the southwest karst area of China and reviews of studies in Europe and other parts of the world. The low soil formation rate and high permeability of carbonate rocks create a fragile and vulnerable environment that is susceptible to deforestation and soil erosion. Other natural processes related to hydrology and ecology could exacerbate rocky desertification. However, disturbances from a wide variety of human activities are ultimately responsible for rocky desertification wherever it has occurred. This review shows that reforestation can be successful in Southwest China and even in the Dinaric Karst region when the land, people, water, and other resources are managed cohesively. However, new challenges may arise as more frequent droughts and extreme floods induced by global climate change and variability may slow the recovery process or even expand rocky desertification. This review is intended to bring attention to this challenging issue and provide information needed to advance research and engineering practices to combat rocky desertification and to aid in sustainable development.





  • Fischel, Richard L.; Wisseman, Sarah U.; Hughes, Randall E.; Emerson, Thomas E. writer Fischel, Richard L.; Wisseman, Sarah U.; Hughes, Randall E.; Emerson, Thomas E. by Fischel, Richard L.; Wisseman, Sarah U.; Hughes, Randall E.; Emerson, Thomas E. published by Fischel, Richard L.; Wisseman, Sarah U.; Hughes, Randall E.; Emerson, Thomas E.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2010
    (AN 56673017)
    America: History & Life
  • 7/5/2015
  • Publication date: August 2014
    Source:Zoology, Volume 117, Issue 4

    Author(s): John W. Rowe , Brittany J. Miller , Mark A. Stuart , Cassandra Snyder , John K. Tucker , David L. Clark , Lawrence W. Wittle , James T. Lamer

    Background color convergence of prey occurring through local adaptation or phenotypically plastic responses can reduce predation rates by visual predators. We assessed the capacity for substrate color-induced melanization in eight turtle species within the groups Chelydridae, Emydidae, Kinosternidae, and Trionychidae by rearing individuals on black or white substrates for 160 days. In all aquatic turtle species, integuments of the head and carapace of the individuals that were reared on a black substrate were darker than of those reared on a white substrate. In the terrestrial turtle Terrapene carolina carolina, however, no significant differences in dorsal head skin or carapace color were observed between treatments. Histological examination of tail tips in three aquatic species (Chelydra serpentina serpentina, Graptemys geographica, and Trachemys scripta elegans) indicated that substrate color-induced melanization is morphological, involving the transfer of melanosomes from basal epidermal melanocytes to adjacent keratinocytes. Interestingly, substrate color-induced melanization in a previously studied Pleurodire species apparently involves physiological color change. We could not, however, rule out physiological components to color change in the turtles of our study.





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  • Publication date: 15 April 2014
    Source:Quaternary Science Reviews, Volume 90

    Author(s): B. Brandon Curry , Edwin R. Hajic , James A. Clark , Kevin M. Befus , Jennifer E. Carrell , Steven E. Brown

    Evidence of the Kankakee Torrent (Ekblaw and Athy, 1925) includes boulder bars formed on a scoured bedrock surface west of Kankakee, Illinois, and overflow channels that connect several moraine-dammed basins (Wauponsee, Watseka, and Pontiac; Willman and Payne, 1942). Geomorphic evidence of a large scale flood event in the Illinois Valley includes features such as erosional residuals (Hajic, 1990). The age of the Kankakee Torrent is about 19,000 cal yr BP based on the pooled mean of four radiocarbon ages of tundra plant stems and leaves from the Oswego channel complex (median probability = 18,930 cal yr BP, σ1 range, 18,870–18,970 cal yr BP). Analysis of recently obtained sediment cores from the middle Illinois River valley near Havana, Illinois, has revealed the bedrock surface is defended by a mantle of bouldery debris buried by 15 m of mostly slackwater lake sediment. Radiocarbon ages of needles archived in the lake sediment reveal evidence for an early lake phase that post-dates the Kankakee Torrent (18,030–17,530 cal yr BP) and a later lake phase (15,690–13,040 cal yr BP). The radiocarbon ages indicate that the deeply buried bouldery rubble was deposited by the Kankakee Torrent. Consideration of isostasy indicates that the earlier lake phase at Havana may have been associated with downward flexure of land surface in response to glacier loading. The younger lake phase was caused in part by deposition of a sediment dam (the Savanna–Deer Plain terrace) at the mouth of the Illinois River. The lake shoaled due to passing of the isostatic forebulge across the area.





  • 7/5/2015
  • Publication date: 15 August 2014
    Source:Science of The Total Environment, Volume 490

    Author(s): Ya Zhang , Walton R. Kelly , Samuel V. Panno , Wen-Tso Liu

    Fecal contamination in Midwestern karst regions was evaluated by simultaneously measuring traditional bacterial indicators (coliforms and Escherichia coli), Bacteroidales-based biomarkers, and environmental variables. Water samples from springs and wells were collected from karst regions in Illinois (IL), Wisconsin (WI), Kentucky (KY), and Missouri (MO). Quantitative PCR (Q-PCR) with seven primer sets targeting different members of Bacteroidales was used to determine the origin of fecal contamination (i.e., from human waste, livestock waste, or both). Most samples were contaminated by both human and animal waste, with a few samples showing pollution solely by one or the other. Spring water tended to have higher levels of contamination than well water, and higher concentrations of fecal biomarkers were detected in urban springs compared to rural spring systems. However, there were discrepancies on contamination profile determined by Bacteroidales-based biomarkers and by traditional bacterial indicators. Among all the environmental parameters examined, E. coli, sulfate, total dissolved solids (TDS), and silicon were significantly correlated (p <0.05) with the level of Bacteroidales-based fecal indicators. A rapid screening method using total nitrogen (TN) and chloride (Cl) concentrations to determine fecal contamination was shown to be effective and correlated well with Bacteroidales-based MST. The results suggest that human and livestock feces co-contaminated a large portion of karst groundwater systems in Midwestern regions, and the inclusion of traditional bacterial indicators, environmental variables, and Bacteroidales-based MST is an effective approach for identifying fecal contamination in karst regions.

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  • Branstner, Mark C. writer Branstner, Mark C. by Branstner, Mark C. published by Branstner, Mark C.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2012
    (AN 85351843)
    America: History & Life
  • Publication date: November 2014
    Source:Arthropod Structure & Development, Volume 43, Issue 6

    Author(s): Mei Su , Christopher H. Dietrich , Yalin Zhang , Wu Dai

    Previous studies of insect spermatozoa indicate that these specialized cells have undergone significant morphological evolution and exhibit traits useful for reconstructing phylogenetic relationships. Although leafhoppers (Cicadellidae) are among the largest and most economically important insect families, few comparative studies of their spermatozoa have been published. Here, the ultrastructure of mature spermatozoa of two leafhoppers Psammotettix striatus (Linnaeus) and Exitianus nanus (Distant), representing two different tribes of the largest leafhopper subfamily, Deltocephalinae, was examined by light and transmission electron microscopy. The shape and ultrastructure of spermatozoa of the two species are very similar to those of other Cicadellidae as well as other Auchenorrhyncha, comprising a conical acrosome invaginated to form a subacrosomal space, a filiform homogeneously condensed nucleus, a lamellate centriolar adjunct connecting the nucleus with the mid-piece/flagellum, a long flagellum with a 9 + 9 + 2 axoneme pattern and two symmetrical mitochondrial derivatives with an orderly array of peripheral cristae, and two drop-shaped accessory bodies. They may be distinguished by the size of the sperm, and the shape of the nucleus, accessory bodies, and paracrystalline region of mitochondrial derivatives. The fine morphology and ultrastructure of spermatozoon in P. striatus and E. nanus are illustrated, along with a brief discussion of the implications for classification and phylogenetic analyses of the subfamily.





  • Fishel, Richard L. writer Fishel, Richard L. by Fishel, Richard L. published by Fishel, Richard L.
    Midcontinental Journal of Archaeology (Rowman & Littlefield Publishers, Inc.); 10/01/2012
    (AN 85351849)
    America: History & Life
  • Publication date: July 2014
    Source:Ocean & Coastal Management, Volume 95

    Author(s): Bingjun Liu , Shulan Yan , Xiaohong Chen , Yanqing Lian , Yanbo Xin

    The Modaomen Waterway (MW), a major outlet of the Pearl River Estuary, is a crucial source of water supply for Macao and Zhuhai City in Southern China. This waterway is frequently affected by saltwater intrusion from the South Sea, which has caused serious water shortage in recent years. For the planning and management of water supply at this waterway it is necessary to understand the characteristics of saltwater intrusion particularly in the low flow period of the year. However, as a result of multiple impacts from tide, river discharge, wind, topography, channel bathometry, and some other factors, the saltwater intrusion into this waterway is highly non-linear. In order to account for the non-linear characteristics, the wavelet method was used to analyze the period characteristics of tidal range, river discharge, and salinity and the impact of tidal range and river discharge on the salinity. Results show that the tidal range at Sanzao station and the salinity at Pinggang station both exhibit a stable 14.8-day period and the salinity in the MW is largely impacted by the tidal range during low stream flow periods. River flows from upstream of the waterway don't show any stable period characteristic, it, however, is critical in mitigating the salinity for water supply during saltwater intrusion. A minimum total flow of 2 500 m3/s from upstream at Sanshui and Makou stations has been practiced as a threshold for safe water supply. This study has found that the percent time when salinity is below the maximum permissible salinity of 250 ml/g for water supply increases as the river discharge from upstream increases and up to 50–70% of the time the salinity at water supply pumping station is below 250 mg/l when the upstream flow is greater than 2 500 m3/s. Planning and management of water supply operation at the MW is politically, economically and mostly importantly technically challenging, findings from this study can provide some guidance for operation and further research. For example, the phase lag of average salinity to tidal range was quantified to be 3.4–3.8 days. This phase lag time would suggest that the pumping operation to store freshwater in the backup storages needs to be at least 4–5 days ahead of the spring tide so as to avoid serious impact from saltwater intrusion. Safer water supply strategies can be developed by scheduling reservoir operations to maintain the threshold stream flow and the pumping.





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