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Number of results: 11
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Abstract

This study was aimed at evaluating the effect of sublethal doses of glyphosate on physiological parameters of a common ornamental plant Mexican marigold (Tagetes erecta). The herbicide was applied in the following doses: 720 g ⋅ ha–1 (standard field dose), 144 g ⋅ ha–1, 28.8 g ⋅ ha–1, and 14.4 g ⋅ ha–1, in the form of a spraying treatment of plants in a specialist spraying chamber. The net assimilation rate and leaf greenness index were then determined. Herbicide application in the sublethal doses, i.e. below 720 g ⋅ ha–1, caused disorders in both analyzed physiological parameters of plants. The glyphosate dose of 144 g ⋅ ha–1 elicited transient disorders in the leaf greenness index. In turn, the use of the lower doses (28.8 g ⋅ ha–1 and 14.4 g ⋅ ha–1) caused a short-term increase in the net photosynthesis rate in the plants which was accompanied by a decreased value of the leaf greenness index. Study results demonstrated the effect of sublethal doses of glyphosate as a stress factor in parameters associated with the process of photosynthesis in plants.

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Authors and Affiliations

Karol Wysocki
Tadeusz Banaszkiewicz
Jacek Olszewski
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Abstract

In the southern Spitsbergen area, thermal and mineral waters are primarily

associated with subpermafrost deep circulation, being mixed with shallow circulation and

glacial waters. Four thermal springs, located in the region of Stormbukta (Sørkappland),

were studied and analyzed. In the thermal waters, the main cation is sodium, while the

main anions are chloride and bicarbonate. The temperatures of the mineral and thermal

waters range from 3.4 to 15.1°C. The pH values are between 7.43 and 8.41. The total

dissolved solids (TDS) content of the geothermal waters is in the range of 346–4031 mg/l

and the Olsok thermal spring has the highest TDS values. Based on the variation in

physicochemical characteristics, two thermal water types were distinguished in the study

area. The first type is associated with thermal waters originating from deep circulation

waters. The second type is associated with the thermal and mineral waters originating

from the mixture of subpermfrost hot brines with glacial waters.

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Authors and Affiliations

Tomasz Olichwer
Robert Tarka
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Abstract

This paper constitutes the sensitivity study of application the Polar WRF

model to the Svalbard area with testing selected parameterizations, including planetary

boundary layer, radiation and microphysics schemes. The model was configured, using

three one-way nested domains with 27 km, 9 km and 3 km grid cell resolutions. Results

from the innermost domain were presented and compared against measured wind speed

and air temperature at 10 meteorological stations. The study period covers two months:

June 2008 and January 2009. Significant differences between simulations results occurred

for planetary boundary layer (PBL) schemes in January 2009. The Mellor-Yamada-Janjic

(MYJ) planetary boundary layer (PBL) scheme resulted in the lowest errors for air

temperature, according to mean error (ME), mean absolute error (MAE) and correlation

coefficient values, where for wind speed this scheme was the worst from all the PBL

schemes tested. In the case of June 2008, shortwave and longwave radiation schemes

influenced the results the most. Generally, higher correlations were obtained for January,

both for air temperature and wind speed. However, the model performs better for June

in terms of ME and MAE error statistics. The results were also analyzed spatially, to

summarize the uncertainty of the model results related to the analyzed parameterization

schemes groups. Significant variability among simulations was calculated for January

2009 over the northern part of Spitsbergen and fjords for the PBL schemes. Standard

deviations for monthly average simulated values were up to 3.5°C for air temperature

and around 1 m s-1 for wind speed.

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Authors and Affiliations

Natalia Pilguj
Bartosz Czernecki
Maciej Kryza
Krzysztof Migała
Leszek Kolendowicz
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Abstract

This article aims to analyse the influence of weather types on meteorological

conditions in Petuniabukta (Svalbard) during July and August of 2016. The paper analyses

the daily courses of air temperature and humidity at four measurement points located on

the west bank of Petuniabukta near Adam Mickiewicz University Polar Station during

two different types of weather conditions: (i) cloudy and windy, (ii) calm and clear.

These weather types, distinguished on the basis of wind speed and cloudiness, allowed

for the creation of composite maps of the synoptic situation (SLP and geopotential

height of 500 hPa distribution) and its anomalies. In the study area, the air temperature

range in windy and cloudy weather conditions was larger (-10°C to 15°C) than that in

sunny and calm weather (0°C to 15°C), which contrasts the range of humidity values.

The diurnal cycle of meteorological elements in sunny and calm days is strongly related

to the sun elevation angle. In the above-mentioned weather types, the air temperature

was higher by several degrees (median 5°C to 8°C) than on windy and cloudy days

(median about 0°C to 6°C) at each measurement point. On days with sunny and calm

weather, a smaller vertical temperature gradient of air is observed (for sunny and calm

days 0.63°C and for windy weather 0.8°C).

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Authors and Affiliations

Sebastian Kendzierski
Leszek Kolendowicz
Marek Półrolniczak
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Abstract

Diatom assemblages from small pools and creeks on the Ecology Glacier

forefield have been investigated. It is the first study in the Admiralty Bay region after

the thorough taxonomic revision of the non-marine Antarctic diatom flora. A total of

122 diatom taxa, belonging to 35 genera were identified. More than 55% of all observed

species have a restricted Antarctic distribution. Another 15% have a marine origin.

Nitzschia gracilis Hantzsch, N. homburgiensis Lange-Bertalot and Planothidium rostrolanceolatum

Van de Vijver et al. dominated the flora. Based on a DCA analysis,

samples were subdivided in three groups reflecting ecological differences. Several samples

(group 1) showed a mixed freshwater/marine diatom composition and are typical for

coastal pools. Two other groups were separated based on the amount of limnoterrestrial

taxa indicating the temporary character of some of the pools.

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Authors and Affiliations

Natalia Kochman-Kędziora
Teresa Noga
Maria Olech
Bart Van De Vijver
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Abstract

Climate change has been affecting plants over the last century and caused

changes in life history features such as the flowering time. Herbarium specimens provide

a snapshot of the past environmental conditions during their collection. The collection

date in a herbarium specimen is a good proxy to determine the flowering period (phenology).

In this study, phenological data from subarctic plant specimens collected over

100 years were gathered by using one of the largest herbarium databases in the World.

The collection dates of 7146 herbarium specimens were analyzed and significant shifts

in the phenology of subarctic plants were detected. In this study, most of the analyzed

142 species in a subarctic biogeographic region tended to flower earlier in the 1950–2018

period compared to the 1900–1949 as a possible result of the climate change. Flowering

time shifted from 8 to 26 days in some species. Changes in flowering time may

alter species interactions, community composition, and species distribution in a region.

Therefore, results of this study may shed light on the possible shifts in phenology and

plant responses under the climate change.

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Authors and Affiliations

Fazlioglu Fatih
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Abstract

In polar regions, apart from tundra and glaciers, geothermally active areas

with elevated temperatures are important elements of ecosystems. One such geothermally

active region characterized by mosaic ecosystems and vast areas covered by recent lava

fields is Iceland. The aim of our study was to explore the diversity of invertebrates

inhabiting geothermally active lava fields in the Krafla area (Iceland). Eight bryophyte

samples were collected from a warm surface, mainly from the steaming areas. We have

found Nematoda, Rotifera, Tardigrada and Oribatida in the samples. Habitat analysis

demonstrated there to be 12 bryophyte species (five liverworts and seven mosses).

The diversity of bryophytes in a single sample ranged from one to six species. The

most common bryophyte was Racomitrium lanuginosum (Hedw.) Brid. Four species

of tardigrades were found, including one that was new. Pilatobius islandicus sp. nov.

is described herein by morphological, morphometric and molecular approaches (COI,

28S rRNA, 18S rRNA). Oribatida mites were identified as two species (Malaconothrus

monodactylus (Michael, 1888) and Camisia foveolata Hammer, 1955). The average density

of invertebrates was 13.1 ind./g with a maximum of 40.8 ind./g calculated per dry

material. The tardigrades found in our study belonged to herbivores, microbivores and

omnivores, whereas the mites belonged to saprophages, which indicates complex trophic

networks in geothermally active lava fields.

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Authors and Affiliations

Jakub Buda
Ziemowit Olszanowski
Mariusz Wierzgoń
Krzysztof Zawierucha

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