Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "seasonal distribution" wg kryterium: Temat


Wyświetlanie 1-11 z 11
Tytuł:
Seasonal pattern of the chlorophyll-a in a coastal lagoon from the Southern Baja California (Mexico), described with in situ observations and MODIS-Aqua imagery
Autorzy:
Jimenez-Quiroz, M.C.
Martell-Dubois, R.
Cervantes-Duarte, R.
Cerdeira-Estrada, S.
Powiązania:
https://bibliotekanauki.pl/articles/2078912.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
chlorophyll a
coastal lagoon
remote sensing
transitional zone
climatology
seasonal pattern
phytoplankton biomass
distribution
multivariate statistical method
MODIS-Aqua data
Opis:
This study aims to estimate, with a climatology perspective, the average seasonal pattern of phytoplankton biomass (SP-PBavg) and its distribution in Bahia Magdalena (Mexico) as a baseline to evaluate PB changes in future studies. This lagoon is in a semi-arid region, lacks river discharges, and channels with vegetation are limited at the north and south zones. SP-PBavg was estimated with chlorophyll-a (chl-a) data obtained in 21 sites on daily MODISAqua imagery (2002—2013; n = 2,418) from a ready-to-use public database. The first step was to establish criteria to use imagery and validate with in situ observations taken in 14 sites (2002—2011; n = 312). MODIS-Aqua overestimated chl-a (mean ± confidence interval95: 5.09 ± 0.97 mg m−3; n = 225); with differences among sites. There were no differences near the inlet lagoon (p <0.05), where the water characteristics are Case-1 while values were significantly higher in the eastern shore and two or three times higher in the mouth of north and south channels, whose water characteristics are similar to Case-2. Multivariate statistical methods allow defining zones into the lagoon and describe their SP-PBavg with both in situ and MODIS Aqua data, but the former’s sample size was small, and the patterns were only delineated. In the inlet surroundings, chl-a peaks from March/April to June/July. On the eastern shore, where MODIS Aqua and in situ data were correlated, despite concentration differences, chla is higher from March/April to October, with peaks in June and September. In the mouth of internal channels, chl-a was higher than other sites and during a longer period; however, the very high MODIS-Aqua values suggest that the satellite also detects organic matter supplied by phytoplankton and other vegetables, which explain the high lagoon’s productivity. These results validate the use of MODIS Aqua imagery to describe the chl-a seasonal patterns in the sea’s vicinity
Źródło:
Oceanologia; 2021, 63, 3; 329-342
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal and diurnal activity of ticks Ixodes ricinus [Linnaeus, 1758] in Masyw Sleza [Lower Silesia]
Autorzy:
Buczek, A.
Lonc, E.
Kucharczyk, K.
Powiązania:
https://bibliotekanauki.pl/articles/837393.pdf
Data publikacji:
1999
Wydawca:
Polskie Towarzystwo Parazytologiczne
Tematy:
Silesian region
seasonal activity
Sleza Massif
diurnal activity
distribution
Lower Silesian region
Ixodes ricinus
tick
Źródło:
Annals of Parasitology; 1999, 45, 4
0043-5163
Pojawia się w:
Annals of Parasitology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal and diel changes in the vertical distribution in relation to the age structure of Microcalanus pygmaeus Sars and Ctenocalanus citer Bowman and Heron, (Pseudocalanidae, Copepoda) from Croker Passage (Antarctic Peninsula)
Autorzy:
Zmijewska, M.I.
Bielecka, L.
Grabowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/47951.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
zooplankton
Antarctic
coastal water
Microcalanus pygmaeus
Pseudocalanidae
vertical distribution
plankton
Ctenocalanus citer
age structure
Antarctic Peninsula
seasonal change
Copepoda
Opis:
The development of two representatives of Pseudocalanidae and the nature of their population distribution in the water column were investigated on the basis of plankton samples collected over three seasons in night-day series in Croker Passage. The investigations showed that the two species begin reproducing in different seasons. Regardless of season, the growth of M. pygmaeus is more advanced than that of C. citer. Both species are characterised by a separation of their populations in the water column. The youngest copepodite stages (I–III) inhabit the upper portion of the water in which the given species occurs, while the oldest specimens, especially males, inhabit the deepest waters. Additionally, the first growth phases (CI–CIII) show a tendency to concentrate closer to the surface at night.
Źródło:
Oceanologia; 2000, 42, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Potential effects of abiotic factors on the abundance and distribution of the plankton in the Western Harbour, South-Eastern Mediterranean Sea, Egypt
Autorzy:
Heneash, A.M.M.
Tadrose, H.R.Z.
Hussein, M.M.A.
Hamdona, S.K.
Abdel-Aziz, N.
Gharib, S.M.
Powiązania:
https://bibliotekanauki.pl/articles/48656.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
plankton
zooplankton
distribution
Western Harbour
Mediterranean Sea
Egypt
abiotic factor
potential effect
abundance
physicochemical parameter
seasonal dynamics
Źródło:
Oceanologia; 2015, 57, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Non-native crab Rhithropanopeus harrisii (Gould, 1984) – a new component of the benthic communities in the Gulf of Gdansk (Southern Baltic Sea)
Autorzy:
Hegele-Drywa, J.
Normant, M.
Powiązania:
https://bibliotekanauki.pl/articles/48242.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
mud crab
Rhithropanopeus harrisii
non-native species
seasonal change
water temperature
distribution
Gdansk Gulf
Baltic Sea
Źródło:
Oceanologia; 2014, 56, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flow, waves and water exchange in the Suur Strait, Gulf of Riga, in 2008
Autorzy:
Raudsepp, U.
Laanemets, J.
Haran, G.
Alari, V.
Pavelson, J.
Kouts, T.
Powiązania:
https://bibliotekanauki.pl/articles/49038.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
flow
wave
water exchange
Suur Strait
Riga Gulf
modelling
shear velocity
Baltic Sea
wind
wind condition
storm
wave heigh
sediment
seasonal cycle
horizontal distribution
outflow
Opis:
Wind, flow and wave measurements were performed in November–December in 2008 in the relatively narrow and shallow Suur Strait connecting the waters of the V¨ainameri and the Gulf of Riga. During the measurement period wind conditions were extremely variable, including a severe storm on 23 November. The flow speed along the strait varied between ±0.2 m s−1, except for the 0.4 m s−1 that occurred after the storm as a result of the sea level gradient. The mean and maximum significant wave heights were 0.53 m and 1.6 m respectively. Because of their longer fetch, southerly winds generated higher waves in the strait than winds from the north. All wave events caused by the stronger southerly winds induced sediment resuspension, whereas the current-induced shear velocity slightly exceeded the critical value for resuspension only when the current speed was 0.4 m s−1. A triplenested two-dimensional high resolution (100 m in the Suur Strait) circulation model and the SWAN wave model were used to simulate water exchange in 2008 and the wave-induced shear velocity field in the Suur Strait respectively. Circulation model simulations demonstrated that water exchange was highly variable, that cumulative transport followed an evident seasonal cycle, and that there was an gross annual outflow of 23 km3 from the Gulf of Riga. The horizontal distribution of waveinduced shear velocity during the strong southerly wind event indicated large shear velocities and substantial horizontal variability. The shear velocities were less than the critical value for resuspension in the deep area of the Suur Strait.
Źródło:
Oceanologia; 2011, 53, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Examination of Seasonal Volatility in HICP for Baltic Region Countries: Non-Parametric Test versus Forecasting Experiment
Autorzy:
Lenart, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/2076445.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
HICP
seasonal volatility
exponential smoothing
nowcasting
predictive distribution
logscore
Opis:
The aim of this paper is to examine the problem of existing seasonal volatility in total and disaggregated HICP for Baltic Region countries (Denmark, Estonia, Latvia, Finland, Germany, Lithuania, Poland and Sweden). Using nonparametric tests, we found that in the case of m-o-m prices, including fruit, vegetables, and total HICP, the homogeneity of variance during seasons is rejected. Based on these findings, we propose an exponential smoothing model with periodic variance of error terms that capture the repetitive seasonal variation (in conditional or unconditional second moments). In a pseudo-real data experiment, the short-term forecasts (nowcasting) for the considered components of inflation were determined using different specifications of considered models. The forecasting performance of the models was measured using one of the scoring rules for probabilistic forecasts called logarithmic score. We found instead that while the periodic phenomenon in variance was statistically significant, the models with a periodic phenomenon in variance of error terms do not significantly improve forecasting performance in disaggregated cases and in the case of total HICP. The simpler models with constant variance of error term have comparative forecasting (nowcasting) performance over the alternative model
Źródło:
Central European Journal of Economic Modelling and Econometrics; 2017, 1; 29-67
2080-0886
2080-119X
Pojawia się w:
Central European Journal of Economic Modelling and Econometrics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution of the sea squirt Ecteinascidia thurstoni Herdman, 1890 (Ascidiacea: Perophoridae) along Suez Canal and Egyptian Red Sea coasts
Autorzy:
Gab-Alla, A.A.-F.A.
Powiązania:
https://bibliotekanauki.pl/articles/47709.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
sea squirt
sea coast
Perophoridae
Suez Canal
seasonal rhythm
Red Sea
Ascidiacea
distribution
Ecteinascidia thurstoni
Opis:
Ecteinascidia thurstoni is a colonial sea squirt. It has a seasonal rhythm and a tropical and subtropical distribution; it is usually present during the summer months. It synthesizes a group of molecules called ecteinascidins. One of these is ET-743, a compound that has a most original anti-tumoral activity and is today considered to be one of the most promising substances effective against various solid-type tumors (currently sold under the trade name of Yondelis for the treatment of sarcomas and related tumors; it is undergoing phase II/III clinical trails for other kinds of tumors). Worldwide, Ecteinascidia species represent the only available source of this bioactive compound, which was first discovered in E. turbinata. During the present study, the ecology of E. thurstoni along the Suez Canal and Red Sea was investigated. Its populations were observed to be highly gregarious due in part to their low larval dispersal, which is very localized; larvae therefore tend to settle close to their parent colonies. It is only recorded in shallow waters (0.5–1.5 m) as an epiphyte on the pneumatophores of mangroves by the Red Sea, on the pilings of jetties, and the metal or cement banks of the Suez Canal. The morphometric characteristics (zooid length, zooid weight, colony weight) of the Suez Canal population differ significantly from those of the Red Sea. Studying the distribution of this species and locating its different populations along the Suez Canal and Red Sea could help to characterize their genetics, chemistry and bacterial communities at different isolated locations. Ultimately, this will help to define the sources of ET-743 and hence promote its biosynthesis on a commercial scale.
Źródło:
Oceanologia; 2008, 50, 2; 239-253
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Detecting cyanobacterial blooms in large North European lakes using the Maximum Chlorophyll Index
Autorzy:
Alikas, K.
Kangro, K.
Reinart, A.
Powiązania:
https://bibliotekanauki.pl/articles/48159.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
maximum chlorophyll index
MERIS sensor
phytoplankton
Cyanoprokaryota
chlorophyll a
seasonal dynamics
spatial distribution
Lake Peipsi
Lake Vortsjarv
Estonia
suspended matter
organic matter
phytoplankton biomass
Opis:
The Maximum Chlorophyll Index (MCI), developed for the MERIS sensor processing scheme, is used to investigate the seasonal dynamics, spatial distribution, and coverage of cyanobacterial blooms over Lake Peipsi (Estonia/Russia) and Lake Võrtsjärv (Estonia). In these optically complex waters, the amounts of suspended matter and dissolved organic matter vary greatly and independently of the phytoplankton biomass. We demonstrate that MCI is a useful, new tool for detecting and estimating cyanobacterial biomass (R2 = 0.73), phytoplankton biomass (R2 =0.70) and chlorophyll a concentration (R2 = 0.64). The MCI-derived results are consistent with known patterns of phytoplankton dynamics in these lakes, whose optical properties are in the same range as in many coastal regions of the Baltic Sea.
Źródło:
Oceanologia; 2010, 52, 2; 237-257
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza logistyki dystrybucji nowych maszyn rolniczych w aspekcie zmian struktury popytu
The analysis of distribution logistics of new farm machines in the context of changes in the demand structure
Autorzy:
Juściński, S.
Powiązania:
https://bibliotekanauki.pl/articles/336012.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Maszyn Rolniczych
Tematy:
maszyny rolnicze
producent
nabywca
dystrybucja
logistyka
sezonowość
badania
Polska
agricultural machines
producer
buyer
distribution
logistics
seasonal character
experimentation
Polska
Opis:
W artykule przedstawiono analizę zagadnień dotyczących logistyki dystrybucji nowych maszyn rolniczych. Scharakteryzowano strukturę rynku maszyn rolniczych w Polsce. Omówiono krajową dystrybucję selektywną prowadzoną przez liderów branży. Przedstawiono graficznie uzyskane wyniki badań poziomu ilościowego sprzedaży maszyn rolniczych. Badania zrealizowano w Dziale Handlowym przedsiębiorstwa będącego autoryzowanym dystrybutorem maszyn i ciągników rolniczych. Cykl wykonanych badań obejmował lata 2003-2010. Wyniki badań poddano opracowaniu statystycznemu przy wykorzystaniu programu R wersja 2.14.1. Wyznaczono trend, wahania przypadkowe i wahania sezonowe dla szeregu obserwacji miesięcznych. Rozkłady czasowe sprzedaży poddano analizie w aspekcie kalendarza zabiegów agrotechnicznych.
The article presents an analysis of issues concerning the distribution logistics of new farm machines. It contains a characterization of the farm machines market in Poland. Selective domestic distribution conducted by leaders in the industry was discussed. The results of surveys of farm machines sales volume were presented in a graphic form. The surveys were carried out in the Sales Department of the enterprise which is an authorized distributor of farm machines and tractors. The series of carried out surveys spanned the years 2003-2010. The results of the surveys were subject to statistical analysis with the use of the R program version 2.14.1. The trend as well as random and seasonal fluctuations for a series of monthly observations were identified. Temporal breakdowns of sales were analysed in the context of the calendar of agrotechnical operations.
Źródło:
Journal of Research and Applications in Agricultural Engineering; 2012, 57, 2; 85-91
1642-686X
2719-423X
Pojawia się w:
Journal of Research and Applications in Agricultural Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-11 z 11

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies