scholarly journals Winter air temperature in Holocene reconstructed from the ice wedges stable water isotopes near Anadyr town

2019 ◽  
Vol 59 (1) ◽  
pp. 93-102 ◽  
Author(s):  
N. A. Budantseva ◽  
Yu. A. Vasil'chuk
Keyword(s):  
Air Temperature ◽  
Sandy Loam ◽  
Peat Bog ◽  
Marine Terrace ◽  
Stable Water Isotopes ◽  
Active Growth ◽  
The Holocene ◽  
Bay Area ◽  
Melted Snow ◽  
Winter Temperatures

The object of research is syncryogenic Holocene strata on the coast of the Onemen Bay, 2 km from the town of Anadyr. In July 2017, the outcrop of the first marine terrace uncovered by strong storms was examined. The stratigraphy of the outcrop was represented mainly by sandy loam (5–7 m thick) covered by peat (1–1.5 m) and underlain by sand. Numerous ice wedges were opened in the upper part of this outcrop. Along with that another outcropping of transect of a lakemarsh basin represented by a peat bog of 2–2.5 m thick underlain by sandy loam was also investigated. Ice wedges occur below the polygonal trenches. The present-day narrow ice wedges were found in the upper part of the peat bog. Two representative fragments of both the above outcrops were thoroughly examined. Radiocarbon dating had shown that accumulation of peat on surface of the first marine terrace started in early Holocene (about 8 ka BP). Accumulation of peatland within the lake-marsh basin was also dated to the beginning of the Holocene (about 9 ka BP). In the middle of the Holocene, it was most likely interrupted as a result of thermokarst processes and bogging of the surface. Formation of peatlands in Chukotka during the Holocene is known to be accompanied by active growth of the ice wedges inside them, so the age of the wedges studied by us was estimated as the beginning of the Holocene. The analysis of stable oxygen and hydrogen isotopes in the Holocene and the modern ice wedges had allowed establishing mainly the atmospheric type of moisture feeding of the wedges (due to melted snow) and lack of noticeable isotope fractionation during the ice formation. It has been found that δ18О and δ2Н values in the Holocene ice wedges were lower than in the modern wedges and snow by an average 2–3 and 7–12 ‰, respectively. Paleotemperature reconstructions performed on the basis of isotopeoxygen data showed that the air temperature of the coldest winter month in the first half of the Holocene in the Onemen Bay area was lower than the present-day ones by an average 2–3 °C, which is in a good agreement with the trend of rising winter temperatures throughout the Chukotka Peninsula, as well as in other areas of Eastern Siberia and Alaska. 

Introduced North American Black Henbane (Hyoscyamus niger) Populations are Biennial

2014 ◽  
Vol 7 (4) ◽  
pp. 624-630 ◽  
Author(s):  
Christa E. Fettig ◽  
Ruth A. Hufbauer
Keyword(s):  
North American ◽  
Common Garden ◽  
Hyoscyamus Niger ◽  
Active Growth ◽  
Black Henbane ◽  
Introduced Populations ◽  
Winter Temperatures ◽  
American Black ◽  
The Relationship ◽  
Bolting And Flowering

AbstractBlack henbane can be either annual or biennial. We investigated which life cycle is found in four introduced western North American populations. Plants were grown in a greenhouse common garden until half were vernalized by exposure to natural winter temperatures, while the other half remained in the greenhouse above 20 C, with 16 h of light and 8 h of dark. In total the plants were monitored 313 d after germination. We measured whether plants bolted, the time it took for bolting to commence, and the size at bolting. All vernalized plants bolted after 117 d of active growth (within 26 d of the end of the vernalization treatment), whereas only 26% of the nonvernalized plants bolted after an average of 278 d of active growth. Vernalized plants bolted at a smaller size than the nonvernalized plants that bolted (28 vs. 41 leaves on average). In the nonvernalized plants, the relationship between time to bolting and size was strong, but not so with the vernalized plants. Our results indicate that introduced black henbane plants are biennial, and that vernalization is more critical to bolting and flowering than reaching a certain size. Nonetheless, the fact that nonvernalized plants were capable of bolting if grown long enough suggests that vernalization is not the only cue that can trigger reproduction in introduced populations.

scholarly journals Modelling of Soil Respiration in Hungary

2006 ◽  
Vol 55 (1) ◽  
pp. 59-68 ◽  
Author(s):  
Ferenc Ács ◽  
H. Breuer
Keyword(s):  
Soil Respiration ◽  
Water Balance ◽  
Air Temperature ◽  
Sandy Loam ◽  
Growing Season ◽  
Biogeochemical Model ◽  
Clay Loam ◽  
Water Balance Components ◽  
Linear Relationships ◽  
Time Periods

The climatology of soil respiration in Hungary is presented. Soil respiration is estimated by a Thornthwaite-based biogeochemical model using soil hydrophysical data and climatological fields of precipitation and air temperature. Soil respiration fields are analyzed for different soil textures (sand, sandy loam, loam, clay loam and clay) and time periods (year, growing season and months).  Strong linear relationships were found between soil respiration and the actual evapotranspiration for annual and growing season time periods. In winter months soil respiration is well correlated with air temperature, while in summer months there is a quite variable relationship with water balance components. The strength of linear relationship between soil respiration and climatic variables is much better for coarser than for finer soil texture.

Temperature studies of termite colonies in living trees.

1964 ◽  
Vol 12 (2) ◽  
pp. 250 ◽  
Author(s):  
T Greves
Keyword(s):  
Diurnal Variation ◽  
Air Temperature ◽  
Tree Trunk ◽  
Winter Temperatures

Temperatures inside colonies of Coptotermes acinaciformis and C. frenchi in living trees are well above those recorded in neighbouring, uninfested, parts of the tree. Temperature readings in a colony of C. acinaciformis varied from 33 to 38�C, i.e. 13-20 degC above that at the centre of the tree trunk. The winter temperatures are associated with the aggregation of termites in the nursery. The movement of termites in the colony was reflected in changes in the nursery temperature. The nursery temperature of a C. frenchi colony showed little diurnal variation; throughout the year the temperature varied from 27 to 36�C, the highest temperatures being recorded in November when alates were present. The tree insulated the C. frenchi colony against fluctuating air temperature in much the same way as a mound insulates a colony of C. lacteus. Temperature studies of this kind have been useful in assessing the results of insecticide treatments.

scholarly journals Control of Black Cutworm on Greens 1992

1994 ◽  
Vol 19 (1) ◽  
pp. 304-304
Author(s):  
Stanley R. Swier ◽  
John S. Weaver
Keyword(s):  
Experimental Design ◽  
Soil Temperature ◽  
Air Temperature ◽  
Soil Texture ◽  
Soap Solution ◽  
Sandy Loam ◽  
Golf Course ◽  
Feeding Damage ◽  
Black Cutworm ◽  
Time Of Application

Abstract The experiment was conducted on a golf course nursery. The experimental design was an RCB, replicated 4 times, with 6 ft × 6 ft plots. Treatments were applied 13 Aug and rated 20 Aug. Liquid treatments were applied with a watering can and granular treatments with a salt shaker applicator. Dylox was watered in with 2 gal/plot. Neem was not watered in. The BCW were predominantly 5th instar. Although neem dried on the foliage, the weather was cool and damp for 3 DAT. Conditions at the time of application were: air temperature, 68.2°F; soil temperature, 65.5°F; thatch depth, 0.75 inch; soil texture, sandy loam. Plots were rated by flushing the plot with a soap solution and counting the emerging BCW. Plots could not be rated for feeding damage due to excessive disease.

Environment influences sugarbeet tolerance to S-metolachlor

2020 ◽  
Vol 34 (4) ◽  
pp. 597-606
Author(s):  
Andrew B. Lueck ◽  
Thomas J. Peters ◽  
Alexa L. Lystad
Keyword(s):  
Air Temperature ◽  
Field Experiments ◽  
Sandy Loam ◽  
Field Capacity ◽  
Growth Chamber ◽  
Silty Clay ◽  
Soil Series ◽  
Fresh Weight ◽  
Row Crops ◽  
Shoot Fresh Weight

AbstractHerbicides used in sugarbeet are commonly adapted from other row crops and may cause injury and yield loss often associated with environmental and edaphic factors. Glyphosate-resistant waterhemp in sugarbeet requires a PRE herbicide, such as S-metolachlor, for its control. The objectives of this research were to evaluate sugarbeet tolerance to PRE S-metolachlor, including air temperature and soil water content interactions with soil series in field and growth chamber experiments. Results from field experiments conducted in 12 environments in 2015, 2016, and 2017 indicated 2.16 or 4.32 kg ai ha−1S-metolachlor applied PRE reduced sugarbeet density and stature but did not reduce root yield, sucrose content, or recoverable sucrose compared with the untreated control in environments with soils with less than 3.5% organic matter (OM) and receiving greater than 40-mm cumulative rainfall within 14 d after planting. In the growth chamber, sugarbeet density and shoot fresh weight following S-metolachlor application was influenced by soil moisture content, air temperature, and soil series but not by S-metolachlor rate. Sugarbeet density and shoot fresh weight were reduced 15% and 106%, respectively, when S-metolachlor was applied to a Glyndon sandy loam (2.6% OM, 9.5% clay) at 100% field capacity (FC) and 14 C compared with S-metolachlor application to a Fargo silty clay (7.7% OM and 54% clay) at 100% FC and 21 C. It is concluded that field selection, rather than herbicide rate, is an important criterion for managing sugarbeet tolerance with S-metolachlor.

scholarly journals Upper Holocene development of vegetation and radiocarbon dating in the vicinity of the Cerhovka Brook (Bohemian-Moravian Uplands, Czech Republic)

2012 ◽  
Vol 39 (4) ◽  
pp. 252-261 ◽  
Author(s):  
Eva Břízová ◽  
Anna Pazdur ◽  
Natalia Piotrowska
Keyword(s):  
Czech Republic ◽  
Pollen Analysis ◽  
Radiocarbon Dating ◽  
Deciduous Forests ◽  
Peat Bog ◽  
The Holocene ◽  
Lime Tree ◽  
Stratigraphic Position ◽  
Palynological Study ◽  
Pollen Analyses

Abstract The paper reports the results of a palynological study of a newly exposed section in the peat sediments of Bezděkov site and its correlation with the previous palaeobotanical studies. The main goal was to elucidate the stratigraphic position and paleogeographic development of fossil peat bog and its environment in the Protected Landscape Area Žďárské vrchy and Železné hory in the Bohemian-Moravian Uplands. The development of peatbog vegetation, as shown by the pollen analysis and radiocarbon dating, took place in the Holocene. Pollen analyses provide evidence for occurrences of wetland assemblages with huge representation of alder wood in all the part of succession, followed by willow near the Cerhovka Brook. Alnus and Abies were the dominant trees during all the time. The deciduous forests consist of elm (Ulmus), oak (Quercus), lime tree (Tilia), maple (Acer) and hazel (Corylus). The mosaic picture of woodland and wetland, which covered this landscape during the Upper Holocene, contrasts with the present day monotonous open lowland. Sediments of the peat bog provide information on the origin and vegetation evolution of this area.

Holocene and Last Interglacial cloudiness in eastern Baffin Island, Arctic CanadaThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network.GEOTOP Publication 2008-0027.

2008 ◽  
Vol 45 (11) ◽  
pp. 1221-1234 ◽  
Author(s):  
Bianca Fréchette ◽  
Anne de Vernal ◽  
Pierre J.H. Richard
Keyword(s):  
Air Temperature ◽  
Growing Season ◽  
Dwarf Shrub ◽  
Interglacial Period ◽  
Vegetation Changes ◽  
Baffin Island ◽  
Last Interglacial ◽  
The Holocene ◽  
Growing Season Length ◽  
Shrub Tundra

This study presents Last Interglacial and Holocene vegetation and climate changes at Fog Lake (67°11′N, 63°15′W) on eastern Baffin Island, Arctic Canada. The vegetation cover is reported as vegetation structural types (or biomes). July air temperature and sunshine during the growing season (June–July–August–September) were reconstructed from pollen assemblages using the modern analogue technique. The vegetation of the Last Interglacial period evolved from a prostrate dwarf-shrub tundra to a low- and high-shrub tundra vegetation. The succession of four Arctic biomes was distinguished from the Last Interglacial sediments, whereas only one Arctic biome was recorded in the Holocene sediments. From ca. 8300 cal. years BP to present, hemiprostrate dwarf-shrub tundra occupied the soils around Fog Lake. During the Last Interglacial, growing season sunshine was higher than during the Holocene and July air temperature was 4 to 5 °C warmer than present. A principal component analysis helped in assessing relationship between floristic gradients and climate. The major vegetation changes through the Last Interglacial and Holocene were driven by July air temperature variations, whereas the minor, or subtle, vegetation changes seem rather correlated to September sunshine. This study demonstrates that growing season sunshine conditions can be reconstructed from Arctic pollen assemblages, thus providing information on feedbacks associated with cloud cover and summer temperatures, and therefore growing season length.

scholarly journals Reconstruction of vegetation in the foothills of the Carpathian Mountains, Gorgany region, in the late glacial (based on pollen data of peat-bog Pidluzhia)

2015 ◽  
pp. 333-340
Author(s):  
Natalia Chumak
Keyword(s):  
Key Words ◽  
Radiocarbon Dating ◽  
Environmental Changes ◽  
Younger Dryas ◽  
Late Glacial ◽  
Peat Bog ◽  
Pollen Data ◽  
Carpathian Mountains ◽  
The Holocene ◽  
Short Period

The environmental changes on short-period stages of the Late Glacial were reconstructed based on pollen data of peat-bog Pidluzhia deposits and their radiocarbon dating. There are the Older and Younger Dryas, the Allerod (three phases) are allocated on palynological data in the Late Glacial. Vegetation had evolved from cold meadows to pine forest during this time. The transition from the Late Glacial to the Holocene was identified by the emergence of broad-leaved trees (elm, oak and linden), the spreading of spruce and disappearance of xerophytic elements. Key words: paleovegetation, paleoclimate, palinology, the Late Glacial, the foothills of the Carpathian Mountains.

scholarly journals Prebloom Treatments to Alleviate Cold Injury in Apple

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 807E-807
Author(s):  
E.W. Stover ◽  
T.E. Paine ◽  
W.C. Stiles
Keyword(s):  
Leaf Area ◽  
Untreated Control ◽  
Fruit Set ◽  
Fruit Size ◽  
Cold Injury ◽  
Seed Number ◽  
Flower Buds ◽  
Active Growth ◽  
Strong Trend ◽  
Winter Temperatures

Damage to xylem subtending apple buds is often observed following very low winter temperatures. Reports suggest that prebloom application of boron, zinc, and urea facilitate recovery. Prebloom nutrient treatments were applied to `McIntosh' and `Empire' at three sites in Spring 1994. The following treatments were applied to drip at half-inch green: boron (22.8 mM, solubor); Zn-EDTA (0.75 mM); boron and Zn-EDTA; boron, Zn-EDTA, and urea (59.4 mM). Another treatment used boron and Zn-EDTA at half-inch green, followed by boron, Zn-EDTA, and urea at pink. Spur leaf area, fruit set, fruit size, and seed number were determined. There were no clear treatment effects at the warmest site (mid-winter low –32C); however, this orchard was more variable than other treatment sites. The intermediate site (mid-winter low –37C) had a strong trend of increasing fruit set in `Empire' and `McIntosh' as more nutrients were applied. The combined half-inch green and pink treatment significantly increased fruit set by 23.8% compared to the untreated control. At the coldest site (mid-winter low –42C), `Empire' again displayed a strong trend of increasing fruit set with additional nutrients. All treatments combining boron and zinc significantly increased fruit set. The combined half-inch green and pink treatment increased fruit set by 43%. At this site `McIntosh' did not respond to treatment. However, `McIntosh' trees had continued active growth into late Fall 1993 and sustained severe cold injury in November. Data suggest that, when they were effective, nutrient treatments resulted in increased retention of flower buds on damaged spurs.

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