Emsian (Late Early Devonian) sponges from west-central and south-central Alaska

2009 ◽  
Vol 83 (2) ◽  
pp. 293-298
Author(s):  
J. Keith Rigby ◽  
Robert B. Blodgett ◽  
Nicolle K. Anderson
Keyword(s):  
Early Devonian ◽  
Type Section ◽  
South Central ◽  
West Central ◽  
Associated Species

Relatively common specimens of the hypercalcified agelasiid sponge Hormospongia labyrinthica Rigby and Blodgett, 1983 and specimens of associated species of Hormospongia have been previously reported from Emsian and Eifelian stratigraphic units at several localities in south-central and southeastern Alaska (Rigby and Blodgett, 1983). Those sponges were first described from the type section of the Eifelian Cheeneetnuk Limestone in the McGrath A-5 quadrangle. Since then several additional specimens of Hormospongia labyrinthica have also been collected from a new locality in the Talkeetna C-6 quadrangle in south-central Alaska (Figs. 1, 2.1), and are documented here.

Two new Devonian spine-bearing pleurotomariacean gastropod genera from Alaska

1989 ◽  
Vol 63 (1) ◽  
pp. 47-52 ◽  
Author(s):  
Robert B. Blodgett ◽  
David M. Rohr
Keyword(s):  
Middle Devonian ◽  
New Genera ◽  
Early Devonian ◽  
Old World ◽  
West Central ◽  
Cool Temperate ◽  
Warm Temperate

Two new spine-bearing gastropods, Chlupacispira spinosa n. gen. and sp. and Spinulrichospira cheeneetnukensis n. gen. and sp., are described from the late Early Devonian (Emsian) and early Middle Devonian (Eifelian), respectively, of west-central Alaska. These represent the earliest reported spiny pleurotomariacean gastropods. Otherwise, spinose pleurotomariaceans are known from strata no older than Carboniferous age. Spinulrichospira cheeneetnukensis n. gen. and sp. appears to represent a more highly ornamented derivative of Ulrichospira Donald. Both new genera are part of the more highly ornamented fauna which occurred in warm equatorial waters of the Old World Realm during the Early and Middle Devonian, in contrast to more weakly ornamented shells of the Eastern Americas Realm and even more weakly ornamented (almost totally “plain”) shells of the Malvinokaffric Realm. The latter two realms are thought to represent subtropical to warm temperate and cool temperate to cool polar conditions, respectively.

TECTONIC EVOLUTION OF THE CONNECTICUT VALLEY REGION IN SOUTH-CENTRAL VERMONT AND WEST-CENTRAL NEW HAMPSHIRE

2017 ◽  
Author(s):  
Gregory J. Walsh ◽  
◽  
Peter M. Valley ◽  
Arthur J. Merschat ◽  
Ryan J. McAleer ◽  
...  
Keyword(s):  
New Hampshire ◽  
Tectonic Evolution ◽  
South Central ◽  
West Central ◽  
Connecticut Valley

Late Silurian-Early Devonian slab break-off beneath the Canadian Appalachians: Insights from the Nashwaak Granite, west-central New Brunswick, Canada

Lithos ◽  
2020 ◽  
Vol 358-359 ◽  
pp. 105393 ◽  
Author(s):  
Wei Zhang ◽  
David R. Lentz ◽  
Kathleen G. Thorne ◽  
Ronald J.R. Massawe
Keyword(s):  
New Brunswick ◽  
Early Devonian ◽  
West Central ◽  
Canadian Appalachians

scholarly journals Clear-Sky Surface Solar Radiation and the Radiative Effect of Aerosol and Water Vapor Based on Simulations and Satellite Observations over Northern China

2020 ◽  
Vol 12 (12) ◽  
pp. 1931
Author(s):  
Guang Zhang ◽  
Yingying Ma
Keyword(s):  
Water Vapor ◽  
Solar Radiation ◽  
Inner Mongolia ◽  
Northern China ◽  
Satellite Observations ◽  
Radiative Effect ◽  
Surface Solar Radiation ◽  
Clear Sky ◽  
South Central ◽  
West Central

The distribution and trend of clear-sky surface solar radiation (SSR) and the quantitative effects of aerosol and water vapor are investigated in northern China during 2001–2015 using radiation simulations and satellite observations. Clear-sky SSR in northern China is high in summer and low in winter, which is dominated by astronomical factors and strongly modulated by the seasonal variations of radiative effects of aerosol (ARE) and water vapor (WVRE). The larger variation of WVRE than ARE indicates that water vapor plays a more important role in moderating the seasonal variation of clear-sky SSR. Clear-sky SSR shows an overall decreasing trend of –0.12 W/m2 per year, with decrease more strongly than –0.60 W/m2 per year in west-central Shandong and increase (about 0.40 W/m2) in south-central Inner Mongolia. The consistency of spatial distribution and high correlation between clear-sky SSR and ARE trend indicate that the clear-sky SSR trend is mainly determined by aerosol variation. Dust mass concentration decreases about 16% in south-central Inner Mongolia from 2001 to 2015, resulting in the increase in clear-sky SSR. In contrast, sulfate aerosol increases about 92% in west-central Shandong, leading to the decreasing trend of clear-sky SSR.

Importance of natural cloud regimes to ecophysiology in the alpine species, Caltha leptosepala and Arnica parryi, Snowy Range Mountains, southeast Wyoming, USA

2015 ◽  
Vol 42 (2) ◽  
pp. 186 ◽  
Author(s):  
Adriana Sanchez ◽  
Nicole M. Hughes ◽  
William K. Smith
Keyword(s):  
Convective Cloud ◽  
Snow Accumulation ◽  
Cloud Formation ◽  
South Central ◽  
Fluorescence Measurements ◽  
Winter Snow ◽  
Alpine Species ◽  
Central Rocky Mountains ◽  
Cloud Patterns ◽  
Associated Species

The south-central Rocky Mountains, USA, are characterised by a dry, continental mesoclimate with typical convective cloud formation during the afternoon. Little is known about the specific influence of such predictable cloud patterns on the microclimate and ecophysiology of associated species. During the summer of 2012, days with afternoon clouds were most common (50% of all days) compared with completely clear (24%) or cloudy days (6.5%). In two representative alpine species, Caltha leptosepala DC. and Arnica parryi A. Gray, fully overcast days reduced mean daily photosynthesis (A) by nearly 50% relative to fully clear days. Mean afternoon A was significantly lower on fully cloudy days relative to days with afternoon clouds only or no clouds in both species. Notably, A did not differ during afternoon cloud days relative to clear afternoons. Afternoon clouds significantly reduced transpiration (E) in C. leptosepala relative to clear days, and both species showed mean reductions in plant water stress (i.e. higher Ψ), though this difference was not significant. Water use efficiency (WUE) (A/E) decreased from morning to afternoon, especially on cloudy days, and the presence of clouds had a positive effect on the light reactions of photosynthesis based on fluorescence measurements (Fv′/Fm′), in both species. Cloudy days were characterised by higher Fv/Fm than afternoon clouds and clear days during both the morning and the afternoon (especially for A. parryi) and recovery to near pre-dawn values for cloudy and afternoon cloud day types, but not clear days. Overall, similar ecophysiological advantages of this typical afternoon cloud pattern was apparent in both species, although their spatial microsite differences related to winter snow accumulation may also play an important role.

scholarly journals Nutritional and Anti-Nutritional Factors in Vicia sativa L. Seeds and the Variability of Phenotypic and Morphological Characteristics of Some Vetch Accessions Cultivated in European Countries

Animals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 44
Author(s):  
Eugeniusz R. Grela ◽  
Wioletta Samolińska ◽  
Wojciech Rybiński ◽  
Bożena Kiczorowska ◽  
Edyta Kowalczuk-Vasilev ◽  
...  
Keyword(s):  
Central Europe ◽  
Hydrogen Cyanide ◽  
Protein Level ◽  
Trypsin Inhibitors ◽  
Vicia Sativa ◽  
Common Vetch ◽  
East Central ◽  
Nutritional Factors ◽  
South Central ◽  
West Central

Agricultural research has traditionally focused on staple crops, while relatively little attention has been given to minor crops. Therefore, this study aimed to determine the nutrient contents and some anti-nutritional factors in the seeds of common vetch (Vicia sativa L.) and the variation of phenotypic and morphological traits in field studies of 44 European accessions, originating from Russia, Ukraine, Poland (east and east-central Europe), the Czech Republic, the Slovak Republic, Hungary (south-central Europe), and Germany (west-central Europe) and grown in the same soil-climate conditions. A three-year field study was conducted from 2010 to 2012. Accessions originating from west-central Europe flowered three days earlier than those from south-central Europe. They also had the lowest seed number per pod (5.9) but the highest thousand seed weight (58 g) (p < 0.05). Vetch lines coming from south-central Europe contained the highest level of crude protein in comparison with vetch seeds originating from west-central Europe (353 vs. 324 g kg−1, respectively) (p < 0.05), but the latter had the highest essential amino acid index value (75 vs. 71 in west-central Europe and south-central Europe, respectively) (p < 0.05). The highest protein level was noted in the seeds of Slovak origin (average 358 g kg−1), whereas the lowest protein level (324 g kg−1) was determined in the Russian and German lines. Vetch grain fat was rich in linoleic (53%) and linolenic (14%) acids. The best n-6/n-3 fatty acid ratio (4) and the highest α-linolenic acid level were exhibited by the Slovak and Polish accessions (p < 0.05). The seeds of vetch accessions from east, east-central, and south-central Europe contained higher levels of (p < 0.05) iron than those originating from west-central Europe. The concentration of tannins, trypsin inhibitors, and hydrogen cyanide reached on average 8, 3, and 81 mg kg−1, respectively. The highest hydrogen cyanide (HCN) levels was determined in the accessions of German and Russian origin (126 and 119 mg kg−1, respectively), and the lowest values were noted in the Slovak and Polish lines (50 and 67 mg HCN kg−1, respectively). Furthermore, the Polish accessions contained the lowest levels of tannins and trypsin inhibitors. Common vetch seeds may be valuable protein feed/food stuff, but their nutritional usefulness is limited by the presence of anti-nutritional factors, especially HCN, which is difficult to remove. Further selection in this direction may be postulated.

Two new cirroidean genera (Vetigastropoda, Archaeogastropoda) from the Emsian (Late Early Devonian) of Alaska with notes on the early phylogeny of Cirroidea

1998 ◽  
Vol 72 (2) ◽  
pp. 265-273 ◽  
Author(s):  
Jiří Frýda ◽  
Robert B. Blodgett
Keyword(s):  
New Species ◽  
Lower Devonian ◽  
New Genus ◽  
New Genus And Species ◽  
Early Devonian ◽  
West Central ◽  
The Family ◽  
First Time ◽  
Stratigraphic Range

Two new cirroidean gastropod genera, Alaskiella (family Porcelliidae) and Alaskacirrus (family Cirridae), from the Emsian (late Early Devonian) of west-central Alaska (Medfra B-4 quadrangle) are described. The shell of Alaskiella medfraensis new genus and species exhibits inclined heterostrophic coiling. This shell character is known among other members of the subclass Archaeogastropoda, but is recorded for the first time within members of the superfamily Cirroidea. Inclined heterostrophic coiling of the shell was probably developed independently in several different groups of the subclass Archaeogastropoda. The new genus Alaskacirrus, represented by Alaskacirrus bandeli new species, is the oldest and only known Paleozoic member of the family Cirridae. This suggests that the family Cirridae was separated from the family Porcelliidae since at least Early Devonian time and that it most probably developed from the subfamily Agnesiinae of the family Porcelliidae. Thus, the stratigraphic range of the family Cirridae is at least from Lower Devonian to Cretaceous, an interval of about 350 million years.

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