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Spatial and temporal variability of soil water content

100%

Oyedele D. J., Tijani F. O.

International Agrophysics

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2010

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tom 24

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nr 2

171-176

2

Spatial and temporal variability of sea surface temperature in the Baltic Sea based on 32-years (1982–2013) of satellite data

100%

Stramska M., Bialogrodzka J.

Oceanologia

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2015

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tom 57

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nr 3

3

Efficacy of time-area method in simulating temporal variation of sediment yield in Chehelgazi watershed, Iran

100%

Khaledi Darvishan A. V., Sadeghi S. H. R., Gholami L.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2010

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tom 42

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nr 1

51-60

The proper prediction of temporal and spatial variation of sediment yield from the watershed is a need for sediment control, river engineering and soil and water conservation studies. The present study was therefore planned to simulate the sediment graphs for Chehelgazi watershed in Gheshlagh dam upstream in Kurdistan Province, Iran, by using Time-Area Method. Towards this attempt, the study watershed was divided into 7 time-area segments based on the time of concentration. The soil erosion in each segment was estimated using the USLE and then routed to the main outlet using sediment delivery ratio as a function of land slope in two adjacent time-areas. The temporal variation of sediment was ultimately predicted with the help of lag time of sediment arrival to the outlet and the concept of superposition for 11 storm events, which occurred during winter 2006 and spring 2007. The comparison between estimated sediment graphs with corresponding observed ones verifi ed the weak capability of the model in simulation of sediment graphs under consideration. The results also verifi ed the calibration necessity of the model to achieve appropriate estimation for important components of the sediment graphs. The results of the calibration fi nally proved the considerable capability of the model in predicting of total volume of sediment yield with respective estimation and verifi cation errors of 30.93 and 33.40%.

4

Relative abundance distributions od species: the need to have a new look at them

100%

Ulrich W.

Polish Journal of Ecology

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2001

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tom 49

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nr 4

5

Observed variability in physical and biogeochemical parameters in the Central Arabian Gulf

84%

Rakib F., Al-Ansari E. M. A. S., Husrevoglu Y. S., Yigiterhan O., Al-Maslamani I., Aboobacker V. M., Vethamony P.

Oceanologia

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2021

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tom 63

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nr 2

6

Can the studies at a spatial scale of 100s meters detect the spatio-temporal fluctuations of a parasite assemblage?

84%

Parietti M., Merlo M. J., Etchegoin J. A.

Acta Parasitologica

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2013

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tom 58

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nr 4

The importance of small-scale heterogeneity in local factors which overrides that of larger-scales factors, suggest that local factors play a major role in determining the richness and prevalence of larval digeneans in intertidal gastropods. The restricted distribution of the snail Heleobia australis along a 500 m transect in Cangrejo creek (Mar Chiquita, Argentina) provides a good opportunity to test the assumption that a study at spatial scale of 100s meters can detect spatiotemporal fluctuations of a larval digenean assemblage. To analyze that, 3600 specimens of H. australis were collected seasonally during the year 2011. A quantitative variation and a space-time interaction between sampling points and seasons of the year for the total prevalence of larval digeneans and snail’s densities were found, as well as a positive correlation with abiotic factors. These results revealed that the fluctuations in the community of larval digeneans of the snail H. australis can be detected at small spatial scale, using its natural distribution of 500 m. This study also highlights the importance of seasonality as a factor that must be considered in studies focused on the search for patterns structuring the communities of larval digeneans, at medium and large scales.

7

The impact of tides and waves on near-surface suspended sediment concentrations in the English Channel

84%

Guillou N., Rivier A., Chapalain G., Gohin F.

Oceanologia

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2017

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tom 59

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nr 1

Numerous ecological problems of continental shelf ecosystems require a refined knowledge of the evolution of suspended sediment concentrations (SSC). The present investigation focuses on the spatial and temporal variabilities of near-surface SSC in coastal waters of the English Channel (western Europe) by exploiting numerical predictions from the Regional Ocean Modeling System ROMS. Extending previous investigations of ROMS performances in the Channel, this analysis refines, with increased spatial and temporal resolutions, the characterization of near-surface SSC patterns revealing areas where concentrations are highly correlated with evolutions of tides and waves. Significant tidal modulations of near-surface concentrations are thus found in the eastern English Channel and the French Dover Strait while a pronounced influence of waves is exhibited in the Channel Islands Gulf. Coastal waters present furthermore strong SSC temporal variations, particularly noticeable during storm events of autumn and winter, with maximum near-surface concentrations exceeding 40 mg l1 and increase by a factor from 10 to 18 in comparison with time-averaged concentrations. This temporal variability strongly depends on the granulometric distribution of suspended sediments characterized by local bimodal contributions of silts and sands off coastal irregularities of the Isle of Wight, the Cotentin Peninsula and the southern Dover Strait.

8

The variability of selected features of Gladiolus imbricatus L. in relation to successive stages of meadow communities following the mowing cessation

84%

Kostrakiewicz-Gieralt K.

Polish Journal of Ecology

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2014

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tom 62

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nr 2

Molinietum caeruleae meadows belong to the most endangered plant communities in Central Europe, nowadays suffering due to the lack of management. The land abandonment promotes strong secondary expansion of macroforbs, sedges or willows, contributing to decrease of the species diversity. In light of these findings very interesting seems to be the evaluation of the variability of features of populations of rare meadow species. In Poland one of strictly protected plant is Gladiolus imbricatus L. It is a tuberous, clonal plant with sword-like leaves and tall stalks bearing purple flowers collected in one-sided inflorescence. The studies of spatio-temporal variability of selected features of subpopoulations of Gladiolus imbricatus were carried out in the years 2009-2011 in Kraków-Kostrze (Southern Poland) in patches of Molinietum caeruleae with different species composition. In Patch I chiefly occurred small meadow species, Patch II was prevailed by shrub willow, Patch III was dominated by tall-growing macroforbs, Patch IV was characterized by substantial share of large-tussock grasses, while Patch V was overgrown by tall rhizomatous grass Phragmites communis. The plant canopy height and ground moisture raised from Patch I, via Patches II, III and IV, to Patch V. Moreover, in all sites the above mentioned parameters increased moderately in consecutive seasons. The decline of abundance of subpopulations observed in the consecutive years and in the successive patches might be caused by a mortality of individuals, a physical damage of tubers, as well as a prolonged dormancy of genets. The structure of developmental stages were similar in consecutive years but differed significantly among Patches. The increasing trend toward senility noted in successive sites could be an effect of lack of microsites suitable for seedling recruitment or absence of vegetative regeneration. The dimensions of leaf blades, flowering stalks and inflorescences remained similar in the subsequent seasons, but they augmented significantly in the successive patches. The length and the width of capsules did not change significantly between seasons and sites. Concluding, it might be assumed, that the perspectives for survivability of subpopulations diminish gradually from Patch I, via Patches II, III and IV to Patch V. Simultaneously, it should be pointed out that prospects for persistence in each place steadily decrease in effect of continuous deterioration of site conditions.

9

Variability of fluorescence of dissolved and suspended substances of biological origin in the Gdansk Basin during the International Ecological Experiment “Sopot 87”

84%

Karabashev G. S., Khanaev S. A., Petrosov A. Y.

Oceanologia

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1990

|

tom 28

10

Temporal variability of nutrients and chlorophyll a in the Boka Kotorska Bay, eastern Adriatic Sea

84%

Krivokapic S., Pestoric B., Drakulovic D.

International Journal of Ecohydrology and Hydrobiology

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2011

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tom 11

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nr 1-2

11

Body size and the relative abundance of species

84%

Ulrich W.

Ecological Questions

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2008

|

tom 10

Existing models of species abundance distributions (SADs) can be divided into those that are based on concepts of common limited niche space (niche apportionment models, neutral models) and those that invoke standard statistical distributions (e. g. log-series, lognormal). While the first type of models assumes that competitive interactions lead to observed SADs, the models of the second type appear to be mainly statistical descriptors of SADs without deeper biological meaning. None of the models explicitly includes species body size as a factor influencing species abundances. Further, with the exception of recent neutral models they are not embedded into basic ecological and evolutionary models to explain local diversity and ecosystem functioning. Here I present a new random walk model of species abundances that is based on two well known ecological distributions, the abundance - body weight distribution and the species - body weight distribution to define long-term upper abundance boundaries (carrying capacities). I show that a simple random walk of species abundances around the carrying capacities not only generates observed SADs but is also able to explain other patterns of community structure like core - satellite distributions, temporal patterns of species turnover, variance - mean ratios, and biomass distributions.

12

Spatio-temporal variability of microbial eukaryotic community composition in a large shallow subtropical lake, assessed by 18SrRNA gene sequences

84%

Chen M., Chen F., Zhao B., Qinglong L. W., Kong F.

Acta Protozoologica

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2009

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tom 48

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nr 3

245-264

13

Recent multiyear trends in the Baltic Sea level

84%

Stramska M., Chudziak N.

Oceanologia

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2013

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tom 55

|

nr 2

14

Spatial and temporal variability of the interception in the natural wetland valley, the lower Biebrza basin case study

84%

Ignar S., Weglewska A., Szporak-Wasilewska S., Chormanski J.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2013

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tom 45

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nr 1

The paper presents the research carried out in the lower basin of Biebrza River valley in order to identify interception for natural wetland plant communities. Maximum interception, i.e. the largest amount of water, expressed in millimeters, which can be captured and retained by plant canopy from rainfall is one of the key parameters of the water cycle modeling. Maximum interception was determined based on the difference of the masses of wet and dry fresh plant samples. Collection of plant material samples took place during the five measurement sessions, which began immediately after the flood recedes, and then lasted until the end of the growing season. Interception spatial variability was analyzed on the basis of the results of maximum interception measured for selected plant aggregations in the different sampling points. The obtained values were extrapolated to the area of the lower basin of Biebrza River using vegetation map of the Biebrza National Park. By conducting a test sessions in the five coming months, the maps of the spatial variability also show changes over time. Methodology used in the described tests allowed for obtaining of satisfactory results. They present, in a correct way, variation occurring between the plant aggregations due to their morphology. In most cases the results are consistent with data from the literature. As results of the analysis of spatial variability of the maximum interception, the highest values were found for the plant communities located in the immediate vicinity of the river channel. With the increase of the distance from river towards the valley edges the maximum interception values decrease. These changes can be seen in the form of strips parallel to the river channel, which corresponds to the plant zones. Obtained map of spatial variability of the maximum interception, which is the results of extrapolation of the values assigned to plant communities, has a high correlation with the map resulting from the analysis of satellite images.

15

Temporal variability of the selected flood parameters in the Biebrza River valley

84%

Ignar S., Maksymiliuk-Dziuban A., Miroslaw-Swiatek D., Chormanski J., Okruszko T., Wysocki P.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2011

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tom 43

|

nr 2

16

Estimating population trends using population viability analyses for the conservation of Capra pyrenaica

84%

Escos J. M., Alados C. L., Pulido A., Romera J., Gonzalez-Sanchez N., Martinez F.

Acta Theriologica

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2008

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tom 53

|

nr 3

Large herbivore populations can suffer important oscillations with considerable effects on ecosystem functions and services, yet our capacity to predict population fate is limited and conditional upon the availability of data. This study investigated the interannual variation in the growth rate of populations ofCapra pyrenaica Schinz, 1838, and its extinction risk by comparing the dynamics of populations that were stable for more than two decades (Gredos and Tortosa-Beceite), populations that had increased recently (Tejeda-Almijara), and populations that were in decline (Cazorla-Segura) or extinct (the Pyrenees population; hereafter, bucardo). To estimate quasi-extinction threshold assessments (50% of population extinct in this study), which have implications for the conservation of the species, we used empirical data and the predictions derived from several theoretical models. The results indicate that when variance of log population growth rate reaches a specific threshold, the probability of quasi-extinction increased drastically. ForC. pyrenaica, we recommend keeping population variance < 0.05, which will reduce the likelihood that the irruptive oscillations caused by environmental and demographic stochasticity will put the population at risk. Models to predict the dynamics ofC. pyrenaica populations should incorporate temporal stochasticity because, in this study, it strongly increased the likelihood that a population declined.

17

Does biotic patchiness in a lake conform to chemical heterogeneity?

84%

Kufel I., Kufel L.

Polish Journal of Ecology

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2001

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tom 49

|

nr 4

18

Salivary aldehyde dehydrogenase - temporal and population variability, correlations with drinking and smoking habits and activity towards aldehydes contained in food

67%

Giebultowicz J., Dziadek M., Wroczynski P., Woznicka K., Wojno B., Pietrzak M., Wierzchowski J.

Acta Biochimica Polonica

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2010

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tom 57

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nr 3

Fluorimetric method based on oxidation of the fluorogenic 6-methoxy-2-naphthaldehyde was applied to evaluate temporal and population variability of the specific activity of salivary aldehyde dehydrogenase (ALDH) and the degree of its inactivation in healthy human population. Analyzed was also its dependence on drinking and smoking habits, coffee consumption, and its sensitivity to N-acetylcysteine. Both the specific activity of salivary ALDH and the degree of its inactivation were highly variable during the day, with the highest activities recorded in the morning hours. The activities were also highly variable both intra- and interpersonally, and negatively correlated with age, and this correlation was stronger for the subgroup of volunteers declaring abstinence from alcohol and tobacco. Moderately positive correlations of salivary ALDH specific activity with alcohol consumption and tobacco smoking were also recorded (rs ~0.27; p = 0.004 and rs = 0.30; p = 0.001, respectively). Moderate coffee consumption correlated positively with the inactivation of salivary ALDH, particularly in the subgroup of non-drinking and non-smoking volunteers. It was found that mechanical stimulation of the saliva flow increases the specific activity of salivary ALDH. The specific activity of the salivary ALDH was strongly and positively correlated with that of superoxide dismutase, and somewhat less with salivary peroxidase. The antioxidant-containing drug N-acetylcysteine increased activity of salivary ALDH presumably by preventing its inactivation in the oral cavity. Some food-related aldehydes, mainly cinnamic aldehyde and anisaldehyde, were excellent substrates of the salivary ALDH3A1 enzyme, while alkenals, particularly those with short chain, were characterized by lower affinity towards this enzyme but high catalytic constants. The protective role of salivary ALDH against aldehydes in food and those found in the cigarette smoke is discussed, as well as its participation in diminishing the effects of alcohol- and smoking-related oxidative stress.

19

Bio-optical trends of seas around Turkey: An assessment of the spatial and temporal variability

67%

Bengil F., Mavruk S.

Oceanologia

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2018

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tom 60

|

nr 4

20

Solar radiation at the surface in the Baltic Proper

67%

Keevallik S., Loitjarv K.

Oceanologia

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2010

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tom 52

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nr 4

Radiation data recorded at 12 sites around the central part of the Baltic Sea during 1996–2000 drawn from the BALTEX (Baltic Sea Experiment) meteorological data archives are used to study the spatio-temporal variability of daily global radiation totals. The annual average daily global radiation total varies from about 10MJ m−2 at Visby (on Gotland) and Kołobrzeg (on the coast of Poland) to less than 9 MJ m−2 at Z¯ıl¯ani (inland Latvia), ˇ Silut˙e (Lithuania) and Jokioinen (Finland). The monthly average daily global radiation total over the whole region extends from 0.93 in December to 19.0 in June. The variability in global radiation is analysed on the basis of the fraction of the daily total at the top of the atmosphere. The spatial and temporal variability is the least in August – this shows that the variation in the cloud cover and atmospheric properties at this time of year is the smallest. The spatial correlation is the strongest between the two Finnish stations – Vantaa and Jokioinen. It is also high between Stockholm and Norrk¨oping, on the east coast of Sweden. The correlation coefficients are the largest over the whole area in April. Radiation data from coastal stations are compared with an earlier parameterization based on ship observations (Rozwadowska & Isemer 1998, Isemer & Rozwadowska 1999). It is concluded that in climatological research, actinometric data from Visby can be used to characterize the radiation field over the northern part of the Baltic Proper and those from Kołobrzeg to characterize the adiation field over the southern part of this sea.

Ograniczanie wyników

Spatial and temporal variability of soil water content

Spatial and temporal variability of sea surface temperature in the Baltic Sea based on 32-years (1982–2013) of satellite data

Efficacy of time-area method in simulating temporal variation of sediment yield in Chehelgazi watershed, Iran

Relative abundance distributions od species: the need to have a new look at them

Observed variability in physical and biogeochemical parameters in the Central Arabian Gulf

Can the studies at a spatial scale of 100s meters detect the spatio-temporal fluctuations of a parasite assemblage?

The impact of tides and waves on near-surface suspended sediment concentrations in the English Channel

The variability of selected features of Gladiolus imbricatus L. in relation to successive stages of meadow communities following the mowing cessation

Variability of fluorescence of dissolved and suspended substances of biological origin in the Gdansk Basin during the International Ecological Experiment “Sopot 87”

Temporal variability of nutrients and chlorophyll a in the Boka Kotorska Bay, eastern Adriatic Sea

Body size and the relative abundance of species

Spatio-temporal variability of microbial eukaryotic community composition in a large shallow subtropical lake, assessed by 18SrRNA gene sequences

Recent multiyear trends in the Baltic Sea level

Spatial and temporal variability of the interception in the natural wetland valley, the lower Biebrza basin case study

Temporal variability of the selected flood parameters in the Biebrza River valley

Estimating population trends using population viability analyses for the conservation of Capra pyrenaica

Does biotic patchiness in a lake conform to chemical heterogeneity?

Salivary aldehyde dehydrogenase - temporal and population variability, correlations with drinking and smoking habits and activity towards aldehydes contained in food

Bio-optical trends of seas around Turkey: An assessment of the spatial and temporal variability

Solar radiation at the surface in the Baltic Proper