scholarly journals Lithobiont-dependent ionic composition in runoff water

2020 ◽  
Vol 68 (3) ◽  
pp. 293-301
Author(s):  
Giora J. Kidron ◽  
Abraham Starinsky
Keyword(s):  
Chemical Composition ◽  
Drainage Basin ◽  
Ionic Composition ◽  
Parent Material ◽  
Negev Desert ◽  
Runoff Water ◽  
The North ◽  
Almost All ◽  
Epilithic Lichens ◽  
Runoff Plots

AbstractRock dwelling organisms (lithobionts) such as cyanobacteria (prokaryotes) and chlorolichens (eukaryotes) abound in the Negev Desert, where they cover almost all calcareous bedrocks and rock particles (cobbles, boulders). In a small limestone watershed in the Negev Highlands, cyanobacteria inhabit the south-facing (SF) bedrocks, epilithic lichens (accompanied by endolithic lichens) inhabit the north-facing (NF) bedrocks, while endolithic lichens cover most of the cobbles and boulders in both aspects. In order to study their contribution to runoff water, a pair of runoff plots was established on habitats with cyanobacteria, endolithic lichens, and epilithic lichens. Rain and runoff were collected during the hydrological year 2006/07, and the chemical composition (Ca, Mg, Na, K, Cl, SO4, HCO3, Si) of the rain and runoff water was analyzed. Several patterns were observed: (a) as indicated by Si, more dust accumulated on the bedrocks; (b) all substrates exhibited high amounts of Ca, and HCO3; (c) while SF-bedrocks showed enrichment in K, both bedrocks (and especially the NF bedrocks), as well as the NF boulders showed an enrichment in Mg. While the enrichment in Ca and HCO3 can be explained by the contribution of the limestone parent material, the enrichment in K and Mg can be explained by the contribution of the living lithobionts, with K being mainly contributed by the cyanobacteria and Mg mainly by the epilithic lichens. Ion enrichment may therefore be aspect-dependent, reflecting the lithobiont distribution within the drainage basin, partially explaining the enrichment in K and Mg previously recorded in runoff water from the Negev.

scholarly journals Research Regarding the Quality of Lambs Carcass Resulted from Tsigaia Purebred Compared with Hybrids of Tsigaia Ewes Crossed with Blanc du Massif Central Rams

2017 ◽  
Vol 74 (1) ◽  
pp. 7
Author(s):  
Mihai Marian BORZAN ◽  
Dana PUSTA ◽  
Liviu BOGDAN ◽  
Alexandra TABARAN ◽  
Attila MATE ◽  
...  
Keyword(s):  
Body Weight ◽  
Chemical Composition ◽  
Massif Central ◽  
Live Body Weight ◽  
Almost All ◽  
Qualitative Characteristics

Abstract: The research aims to compare some qualitative characteristics of purebred Tsigaia lambs and Tsigaia crossed with Blanc du Massif Central lambs. The criteria assessed were: chemical composition of purebred and Tsigaia crossed meat, the live body weight, the slaughtering performance, the weight of different carcass cut. For almost all criteria chosen the crossed individuals registered better results.

scholarly journals A Polar Low Pair over the Norwegian Sea

2009 ◽  
Vol 137 (8) ◽  
pp. 2559-2575 ◽  
Author(s):  
Burghard Brümmer ◽  
Gerd Müller ◽  
Gunnar Noer
Keyword(s):  
Heat Budget ◽  
Cloud Layer ◽  
Sea Surface ◽  
Cloud Base ◽  
Aircraft Measurements ◽  
Polar Lows ◽  
The North ◽  
Polar Low ◽  
Upper Level Jet ◽  
Almost All

Abstract During the Lofotes cyclone experiment (LOFZY 2005), two polar lows developed one behind the other inside a cold-air outbreak from the north in the lee of Spitsbergen on 7 March 2005. Buoys, ship, and aircraft measurements as well as satellite imagery are applied to analyze the polar low bulk properties, the horizontal and vertical structure, and the mass, moisture, and heat budget. The lifetime of the system until landfall at northern Norway was 12 h. The generation occurred under the left exit region of an upper-level jet with 70 m s−1. Both polar lows had a radius of 100–130 km and extended to a height of about 2.5 km. The propagation speeds were within 14–17 m s−1 and correspond to the vertically averaged wind velocity of the lowest 2.5 km. In the polar low centers the pressure was about 2–3 hPa lower and the air was 1–2 K warmer and drier than in the surroundings. Aircraft measurements in the second of the two polar lows show an embedded frontlike precipitation band north of the center. Here, the highest low-level winds with 25 m s−1 and the largest fluxes of sensible and latent heat with 290 and 520 W m−2, respectively, were measured (areal averages amounted to 115 and 190 W m−2). Aircraft data show mass convergence in the subcloud layer (0–900 m) and divergence in the cloud layer (900–2500 m). Moisture supply by evaporation from the sea surface was about twice as large as that by convergence in the subcloud layer. The condensation rate in the cloud layer nearly equaled the rate of evaporation at the sea surface. Almost all condensed cloud water was converted to precipitation water. Only half of the precipitation at the cloud base reached the sea surface.

Epicuticular waxes of the genus Hordeum: a survey of their chemical composition and ultrastructure

1989 ◽  
Vol 67 (11) ◽  
pp. 3219-3226 ◽  
Author(s):  
Bernard R. Baum ◽  
A. Pat Tulloch ◽  
L. Grant Bailey
Keyword(s):  
Chemical Composition ◽  
Discriminant Analysis ◽  
Alcohol Content ◽  
Total Absence ◽  
Average Alcohol ◽  
The Common ◽  
Group 2 ◽  
Whole Plants ◽  
Almost All ◽  
Group 1

This study was based on 148 accessions representing 39 species of Hordeum. SEM ultrastructural morphology of waxes was based on individual spikelets, whereas waxes' chemical composition was assessed from whole plants. When all the data, in the form of individual accessions, were subjected to various cluster analyses methods, no groupings were revealed. But when the data were first summarized by species and then subjected to clustering, two polythetic groups of species were detected. Group 1 is characterized by species with 40–60% average alcohol content and by the common presence of diketones, whereas group 2 is characterized by species with 61 – 80% average alcohol content, by the total absence of hydroxy-β-diketone, and almost all species without β-diketone. The chemical data were then subjected to classificatory discriminant analysis to assess if a single previously unclassified accession could be identified into one of the two groupings. The nature of the differences between the two groupings was described by means of a canonical discriminant analysis. Mostly only plates and filaments were detected, and in many accessions the filaments were widened, appeared platelike, and were characteristic for one group. Presence of β-diketone varied within species. Hordeum violaceum was found to be unique in chemical composition.

United Front: Partisans of the Leningrad Region and their connections with the Central Asian Soviet Republics

2021 ◽  
Vol 2021 (02) ◽  
pp. 214-225
Author(s):  
Sergey Kulik ◽  
Аnatoliy Kashevarov ◽  
Zamira Ishankhodjaeva
Keyword(s):  
World War Ii ◽  
Weather Conditions ◽  
Leningrad Region ◽  
World War ◽  
North West ◽  
The North ◽  
Occupied Territory ◽  
Central Asian ◽  
The Difference ◽  
Almost All

During World War II, representatives of almost all the Soviet Republics fought in partisan detachments in the occupied territory of the Leningrad Region. Among them were many representatives of the Central Asian republics: Kazakhstan, Kyrgyzstan and Uzbekistan. Many Leningrad citizens, including relatives of partisans, had been evacuated to Central Asia by that time. However, representatives of Asian workers’ collectives came to meet with the partisans. The huge distance, the difference in cultures and even completely different weather conditions did not become an obstacle to those patriots-Turkestanis who joined the resistance forces in the North-West of Russia.

Regulation of rectal secretion in saline-water mosquito larvae living in waters of diverse ionic composition

1977 ◽  
Vol 66 (1) ◽  
pp. 83-96 ◽  
Author(s):  
T. J. Bradley ◽  
J. E. Philips
Keyword(s):  
Chemical Composition ◽  
External Medium ◽  
Saline Water ◽  
Ionic Composition ◽  
Malpighian Tubules ◽  
Fluid Composition ◽  
Mosquito Larvae ◽  
Major Site ◽  
Osmotic Concentration ◽  
Anal Papillae

1. Larvae of the saline-water mosquito Aedes campestris were adapted to three waters, all having an osmotic concentration of 700 mOsm, but differing in ionic rations. The (Na+Mg) SO4 medium was much moretoxic than the NAHCO3 or the NaCl media. 2. Ionic and osmotic concentrations of haemolymph and rectal secretion were measured in larvae adapted to all three media. The ratio of ionic concentrations in the rectal secretion reflected those in the external medium to which the larvae had been adapted, with the exception of SO42-, which was possibly replaced by HCO3-in the secretion. These differences in rectal fluid composition persisted even though all ligated recta were bathed in the same artificial haemolymph. 3. The Malpighian tubules were found to be the major site of SO42- excretion. In media containing high levels of NA+, Mg2+, K+, Cl- and HCO3-, the rectum secreted a hyperosmotic fluid containing these ions at concentrations several times greater than those found in the haemolymph. 4. These data provide the basis for speculation on the functioning of anal papillae in waters of diverse chemical composition.

scholarly journals V.—Geology of the Channel Islands

1878 ◽  
Vol 5 (2) ◽  
pp. 79-86 ◽  
Author(s):  
J. A. Birds
Keyword(s):  
Atlantic Coast ◽  
Channel Islands ◽  
The North ◽  
The World ◽  
Almost All ◽  
Extended View ◽  
European Coast

In the most extended view, the Channel Islands may be regarded as fragments and relics of the Eastern or European coast of the Atlantic, reckoning from the North Cape to Cape St. Vincent, and including the Western shores of Scotland and Ireland, and the promontories of Pembrokeshire and Cornwall. They are excellent illustrations, says Professor Ansted, “of those spurs and tongues of porphyritic rock, of which almost all the promontories of the Atlantic coast of Europe consist.” Very small and insignificant specks indeed they seem in such a length of coast, stretching from lat. 37° to 72°, or upwards of 2000 miles; but there is a charm in such wide horizons, and it is a very allowable indulgence so to connect the little with the great, and to consider the position of such little specks in relation to the geography of Europe; one might almost as well say, of the world at large.

scholarly journals Reconstruction of North American drainage basins and river discharge since the Last Glacial Maximum

2016 ◽  
Vol 4 (4) ◽  
pp. 831-869 ◽  
Author(s):  
Andrew D. Wickert
Keyword(s):  
North American ◽  
Drainage Basin ◽  
Ice Sheets ◽  
Glacial Isostatic Adjustment ◽  
Drainage Basins ◽  
Last Glacial ◽  
Isostatic Adjustment ◽  
The North ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Abstract. Over the last glacial cycle, ice sheets and the resultant glacial isostatic adjustment (GIA) rearranged river systems. As these riverine threads that tied the ice sheets to the sea were stretched, severed, and restructured, they also shrank and swelled with the pulse of meltwater inputs and time-varying drainage basin areas, and sometimes delivered enough meltwater to the oceans in the right places to influence global climate. Here I present a general method to compute past river flow paths, drainage basin geometries, and river discharges, by combining models of past ice sheets, glacial isostatic adjustment, and climate. The result is a time series of synthetic paleohydrographs and drainage basin maps from the Last Glacial Maximum to present for nine major drainage basins – the Mississippi, Rio Grande, Colorado, Columbia, Mackenzie, Hudson Bay, Saint Lawrence, Hudson, and Susquehanna/Chesapeake Bay. These are based on five published reconstructions of the North American ice sheets. I compare these maps with drainage reconstructions and discharge histories based on a review of observational evidence, including river deposits and terraces, isotopic records, mineral provenance markers, glacial moraine histories, and evidence of ice stream and tunnel valley flow directions. The sharp boundaries of the reconstructed past drainage basins complement the flexurally smoothed GIA signal that is more often used to validate ice-sheet reconstructions, and provide a complementary framework to reduce nonuniqueness in model reconstructions of the North American ice-sheet complex.

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