Wyniki wyszukiwania - Biblioteka Nauki

1

Temporal changes in the concentrations of zinc and cadmium in the sedimentary strata of Nozha Hydrodrome, Alexandria, Egypt

100%

Rifaat A. E. , Ahdy H. H. H.

Oceanologia

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2011

|

tom No. 53 (4)

993-1004

EN

This study is concerned with the temporal changes in the levels of zinc and cadmium in the sediments of Nozha Hydrodrome during the past 100 years. Seven sediment core samples, covering the study area, were collected from the bottom of the Hydrodrome. A five-step sequential extraction technique was applied to determine the solid phase concentrations of zinc and cadmium. Zinc gives an idea of the quantities of sewage effluents, while cadmium provides an indication of the amounts of agricultural discharges. The vertical distribution curves show that the average total concentrations of zinc in the sediments increased at a rate of 2.5 μg g-1 y-1 from 1900 to 1950 and at 1.5 μg g-1 y-1 from 1950 to 1990. Since 1990 the zinc concentration in Nozha Hydrodrome sediments has been decreasing at 1.5 μg g-1 y-1. The average total cadmium concentration exhibits a different vertical distribution pattern: it increased at a rate of 0.42 μg g-1 y-1 from 1900 to 1950, after which it became constant from 1950 to 1970. Since 1970 it has been increasing at 0.53 μg g-1 y-1. The ongoing increase in cadmium concentrations in the sediments is due to the increase in agricultural discharges into the Hydrodrome, especially as significant amounts of phosphate fertilizers are used to nourish the soil around the Hydrodrome. The rise in cadmium concentrations since 1900 has been accompanied by a similar increase in zinc concentrations with time resulting from the discharge of untreated sewage into the Hydrodrome. In 1990 a sewerage system and sewage treatment plant came into operation, as a result of which discharges of domestic effluent into the Hydrodrome ceased. Since then the amount of zinc in sediments has been decreasing steadily.

2

Temporal changes in the phytoplankton structure in a shallow, macrophyte-dominated lake [Lake Luknajno, Northeast Poland]

75%

Jaworska B. , Kruk M.

Oceanological and Hydrobiological Studies

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2007

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tom 36

|

nr Suppl.1

3

Modeling the spatial and temporal dispersal of Cuscuta europea (Cuscutaceae)

63%

Meri A. , Karsai J.

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tom 61

|

nr 4

EN

Cuscuta species are interestingly behaving plant parasites of very different plant communities all over the world. Under warmer climate conditions they can act as dangerous pests, while in the northern countries they are considered as threatened species. Moreover these plants have a special strategy to find their host, called foraging. Chemical clues emitted by the host plants attract the parasite shoots to the most proper host. Recent papers investigate the host preference of Cuscuta species. In our research, we examine the appearing spatial patterns with both experimental and modelling tools. Our objective is to reproduce this phenomenon in the virtual space and find the model, which best describes the emerging spatial patterns. For the modelling cellular automata are used, which are commonly used tools in spatial ecology. These are spatially explicit dynamic models, where both time and space are discrete. The graphical representation is a squared lattice. Every square – also called cell – in the lattice has a state (e.g. soil, plant, parasite) represented with an appropriate colour. In this paper we present the results of our field observations as well as the mathematical models considered.

4

On currents in the coastal zone of African shelf off Saint Louis

63%

Catewicz Z. , Siwecki R.

|

1985

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tom 21

5

Changes in some elements of the water cycle in the Easternmost part of the Baltic Sea Drainage Basin between 1945 and 2010

63%

Speranskaya N. A.

Oceanologia

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2011

|

tom 53

|

nr (1-TI)

EN

Soil moisture and evaporation are the most important elements of the terrestrial water cycle. In situ data from 14 stations with soil moisture observations, 13 stations with pan evaporation and 200 stations with precipitation measurements are used to analyse temporal changes in these elements of the terrestrial water cycle over the Russian part of the Baltic Sea Drainage Basin. It was determined that soil moisture, pan evaporation and visible evaporation have exhibited significant changes during the past 45 years. These changes reflect the non-uniform character of moistening changes over the Russian part of the Baltic Sea region.

6

Temporal changes of sediment dynamics within the Nairobi River sub-basins between 1998-2006 time scale, Kenya

63%

Kithiia S. M. , Wambua B. N.

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

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2010

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tom 42

|

nr 1

17-22

EN

The city of Nairobi is the heart of both industrial production and the economic hub in Kenya and the Eastern Africa region. The city of Nairobi and its environs are drained by three streams, namely: Nairobi, Mathare and Ngong rivers. These streams drain areas of diverse land use activities. The land use changes in a spatial manner from the rich agricultural system through residential cum urban to industrial. The signifi cance of these various land use systems to pollutants generation, pollution, sediment generation and hence water pollution and quality degradation is quite enormous and worth investigation. The land use changes in a spatial manner making the basin ideal for a temporal variation of sediments yields along the river profi le and their impacts on the water quality status. This paper examines the results of study carried out within the basins in the years 1998–2006. The method of study involved water sampling and laboratory analysis to reveal the trends in sediment load increases downstream the investigated streams. Soil samples were also investigated to determine their relationship to soil erosion rates and sediment fl uxes. The study attempts further to fi nd the best sediment management strategies in reversing their increasing trends and restoring water quality within the basin.

PL

Miasto Nairobi jest centrum produkcji przemysłowej i centrum ekonomicznym Kenii oraz wschodniego regionu Afryki. Miasto Nairobi i jego otoczenie jest odwadniane przez trzy następujące strumienie: Nairobi, Mathare i Ngong. Te strumienie odwadniają obszary o różnym użytkowaniu i działalności. Użytkowanie terenu zmienia się w sposób przestrzenny od bogatego systemu rolnego poprzez miejski mieszkaniowy do przemysłowego. Znaczenie tych różnych systemów użytkowania terenu było bardzo istotne i warte badań z punktu widzenia tworzenia zanieczyszczeń, zanieczyszczenia i generacji rumowiska a tym samym zanieczyszczenia wody oraz degradacji jakości. Zmiany przestrzenne użytkowania terenu czynią zlewnie idealnymi dla czasowych zmian przyrostu ilości rumowiska wzdłuż profilu rzeki i ich wpływu na stan jakości. W referacie przedstawiono wyniki badań przeprowadzonych w zlewniach w latach 1998–2006. Metoda badań obejmowała pobór próbek wody i analizę laboratoryjną w celu określenia trendów zwiększenia ilości rumowiska w badanych strumieniach w ich odcinkach dolnych. Próbki rumowiska były także badane w celu określenia ich zależności od wielkości erozji i strumieni rumowiska. Badania mają na celu znalezienie najlepszych strategii gospodarowania rumowiskiem w celu odwrócenia ich trendów wzrostowych i przywrócenia jakości wody w zlewni.

7

Temporal patterns of wetland-associated bird assemblages in altered wetlands in Turkey

63%

Keten A. , Sarcan E. , Anderson J. T.

Polish Journal of Ecology

|

2019

|

tom 67

|

nr 4

8

Temporal changes in gametogenesis of the invasive Chinese pond mussel Sinanodonta woodiana (Lea, 1834) (Bivalvia: Unionidae) from the Konin lakes system (Central Poland)

63%

Hliwa P. , Zdanowski B. , Dietrich G. J. , Andronowska A. , Krol J. , Ciereszko A.

Folia Biologica

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2015

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tom 63

|

nr 3

9

Acoustic noise generation under plunging breaking waves

63%

Klusek Z. , Lisimenka A.

Oceanologia

|

2013

|

tom 55

|

nr 4

10

No recent temporal changes in body size of three Danish rodents

63%

Yom-Tov Y. , Yom-Tov S. , Jensen T. S. , Baagoe H.

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nr 1

EN

We used museum collections to study temporal trends of possible changes in skull size, body mass and body length in three species of rodents in Denmark. Skulls of adult Microtus agrestis, Apodemus flavicollis and Apodemus sylvaticus, collected between 1895 and 2004, 1847 and 2002, and 1895 and 2002, respectively, were measured and data on body mass and length were taken from the museum registers. Principal component (PC) analysis was used to combine data of the four skull measurements taken. We tested the relationship of sex, latitude, longitude, month and year of collection to PC1 by a General Linear Model (GLM). PC1, body length and body mass of M. agrestis significantly increased from west to east. In addition, PC1, body mass and body length of M. agrestis declined from summer (August) through autumn and winter to spring (March), probably due to the decline in food availability towards winter. None of the other factors examined (sex, latitude and year) were significantly related to body size. PC1 of A. flavicollis and A. sylvaticus was not significantly related to any of the environmental factors examined.

11

Temporal and spatial changes of cadmium in the near-bottom suspended matter of the Pomeranian Bay - Arkona Deep system

63%

Staniszewski A. , Pazdro K. , Beldowski J. , Leipe T. , Emeis K. C. , Pempkowiak J.

Oceanologia

|

2000

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tom 42

|

nr 4

EN

Owing to the high toxicity of cadmium (Cd) towards biota and the considerable quantities of this element entering the environment from anthropogenic sources, interest in its biogeochemistry is increasing. This is also true for the marine environment, which serves as a sink for both natural and anthropogenic Cd loads entering the hydrosphere and the atmosphere. The distribution of Cd in the coastal zone of the marine environment is governed primarily by the flux of the so-called fluffy layer suspended matter (FLSM), which spreads across the top of the sea floor as a several-centimetre-thick layer containing highly concentrated suspended matter. Both total contents and solid speciation of Cd was measured in FLSM collected in the Pomeranian Bay – Arkona Deep system (Western Baltic Proper) in the course of the three-year-long study. Seasonal changes in the total Cd content (0.5–1.8 μg g−1 dry matter) were attributed to the contribution of organic suspensions originating from algal blooms. The decreasing content of Cd in FLSM offshore is due to the input of Cd-rich suspended matter from the River Odra (Oder), and the decreasing organic matter content in FLSM with increasing depth. The contribution of labile fractions (adsorbed and bound to iron(III) hydroxides) was found to be from 50 to 75% of the total content. In view of the substantial mobility and bioavailability of the fractions, this is a highly alarming feature.

12

Temporal changes of aquatic macrophytes vegetation in a lowland groundwater feed eutrophic course [Klatovske Rameno, Slovakia]

63%

Otahel'ova H. , Hrivnak R. , Valachovic M. , Janauer G. A.

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nr 2

EN

Klátovské rameno is the lowland slow-flowing groundwater feed eutrophic tributary of the Malý Dunaj River (Danube Plain), where our study of temporal changes of aquatic macrophytes vegetation was realised in 1999 and 2005. For survey of aquatic vascular macrophytes the Kohler’s method (Janauer 2003) was used, which is compliant with European standard EN 14184. Altogether 35 aquatic macrophyte species were recorded during the survey. Nuphar lutea persisted as the most dominant species in 1996 and 2005. Species diversity increased slightly after the nine years: ten species immigrated to the watercourse. The changes in species abundance have shown weak differences, however the abundance of Sparganium emersum has increased markedly. Alien species Elodea canadensis and both S. emersum and Hydrocharis morsus-ranae significantly enlarged their distribution in the stream. The ecological quality of the river, based on the aquatic macrophytes assessment criteria, was slightly impaired after nine years, but still 90% of its studied course has a high or good ecological status.

13

Changes in land use in an historical area of Central Italy over twenty years: the use of environmental indicators

51%

Bodesmo M. , Romano B. , Pacicco L. , Cagiotti M. R. , Ranfa A.

Polish Journal of Ecology

|

2010

|

tom 58

|

nr 3

EN

The analysis of the area of the municipality of Tu oro sul Trasimeno in Umbria, Central Italy (the historical site of the Battle of Trasimeno in 217 BC) was carried out to evaluate changes in land use from 1977 to 2000 at the land-plot level using relevant land use maps. An evaluation of the environmental quality of land use in 2000 was also made. The study involved an analysis of the environmental diversity in terms of extent and variety of land use. The Landscape Conservation Index (ILC), and diversity indicators (Shannon-Wiener Index and Eveness Index) were calculated. The study showed how landscape quality gradually declined due to an increase in agricultural areas to the detriment of natural areas. The calculation of environmental indicators, particularly the Eveness Index showed how the difference between real and potential diversity increased, in favour of real diversity. This is a symptom of increased human pressure.

14

Phytoseston and heterotrophic bacteria in the assessment of the waters in the Welna and Nielba Rivers

51%

Messyasz B. , Szczuka E. , Kaznowski A. , Burchardt L.

|

nr 4

15

Numerical modelling of POC dynamics in the Southern Baltic under possible future conditions determined by nutrients, light and temperature

51%

Dzierzbicka-Glowacka L. , Kulinski K. , Maciejewska A. , Jakacki J. , Pempkowiak J.

Oceanologia

|

2011

|

tom 53

|

nr 4

EN

This paper discusses predictions of particulate organic carbon (POC) concentra- tions in the southern Baltic Sea. The study is based on the one-dimensional Particulate Organic Carbon Model (1D POC), described in detail by Dzierzbicka- Głowacka et al. (2010a). The POC concentration is determined as the sum of phytoplankton, zoo- plankton and dead organic matter (detritus) concentrations. Temporal changes in the phytoplankton biomass are caused by primary production, mortality, grazing by zooplankton and sinking. The zooplankton biomass is affected by ingestion, excretion, faecal production, mortality and carnivorous grazing. The changes in the pelagic detritus concentration are determined by the input of dead phytoplankton and zooplankton, the natural mortality of predators, faecal pellets, and sinks – sedimentation, zooplankton grazing and biochemical decomposition. The model simulations were done for selected locations in the southern Baltic Sea (Gdańsk Deep, Bornholm Deep and Gotland Deep) under predicted conditions characterized by changes of temperature, nutrient concentrations and light availability. The results cover the daily, monthly, seasonal and annual POC concentration patterns in the upper water layer. If the assumed trends in light, nutrients and temperature in the southern Baltic correctly predict the conditions in 2050, our calculations indicate that we can expect a two- to three-fold increase in POC concentration in late spring and a shift towards postponed maximum POC concentration. It can also be anticipated that, as a result of the increase in POC, oxygenation of the water layer beneath the halocline will decrease, while the supply of food to organisms at higher trophic levels will increase.

16

Temporal and spatial changes in the bio-optical properties of seawater in the Nordic Seas – AREX’2003 and 2006

51%

Drozdowska V. , Paryvkina L.

Oceanologia

|

2011

|

tom 53

|

nr 3

EN

For many years the Nordic Seas have been the subject of research into ocean circulation carried out by the Institute of Oceanology PAS, especially the inflow of Atlantic water and the intensive turbulent mixing of these waters with Arctic and shelf waters. Ocean currents affect various biological processes, among them the supply of organic matter and oxygen, which constitute the foundation for the unique flora and fauna of the Svalbard islands. Spectrophotometric examinations of surface waters using an M32 B spectroflu- orophotometer (LDI Ltd.) were carried out repeatedly during Arctic cruises on board r/v ‘Oceania’. The results presented in this paper come from the AREX campaigns of 2003 and 2006. Analysis of the chlorophyll a fluorescence excitation spectra recorded shows an increase in phytoplankton abundance and the changes in the spatial distribution of the phytoplankton species characteristic of Atlantic, Arctic and shelf waters. The spatial patterns of the phytoplankton pigments and their abundance were compared with the physical characteristics of water masses. The analysis confirmed that phytoplankton species move together with the Atlantic water as this flows into northern latitudes.

17

Relationship between nematode community and biomass and composition of periphyton developing on artificial substrates in floodplain lake

51%

Vidakovic J. , Palijan G. , Cerba D.

Polish Journal of Ecology

|

2011

|

tom 59

|

nr 3

EN

Periphyton colonisation on artificial substrate (microscopic glass slides) was investigated from July to November 2007, in Lake Sakadaš (Danube River floodplain Kopački rit, Croatia). Two different stations were chosen due to different post – flood conditions. The aim of the study was to follow temporal changes of nematode community composition and trophic structure in relation to periphyton biomass and bacterial abundance. In bryozoan – dominated periphyton (Plumatella emarginata Allman, 1844) nematodes were represented by 86 and 87% of total associated invertebrate fauna at S1 and S2 respectively. Total nematode abundance (up to 600 ind. 10 cm-2 at one station and up to 1130 ind. 10 cm-2 at another station) correlated significantly with the abundance (meaured as CFUs – colony forming units) of copiotrophic and oligotrophic bacteria at one station (r = 0.963, 0.998, P <0.05) and with organic and inorganic content of periphyton at another station (r = 0.891, 0.899, P <0.05). Nematode trophic groups (epistrate feeders, chewers, detritus feeders and suction feeders) were equally developed at both stations except detritus feeders whose species richness and abundance were significantly higher at the S1. Epistrate feeders were the most abundant trophic group in nematode assemblages at both stations with Chromadorina bioculata being the dominant species. Change in dominance of epistrate feeders by chewers (Brevitobrilus stefanskii) and suction feeders (Crocodorylaimus sp.) coincided with the occurrence of flood pulse. Effect of flood pulse on nematode community structure was probably indirect, alterating concentration of dissolved oxygen which chromadorids are sensitive to. The structure of nematode community developed through time differs between investigated stations indicating high sensitivity to bacterial abundance, periphyton biomass and P. emarginata mats which made the habitat more diverse and patchy.

18

Patterns of genetic diversity in populations of Filipendula ulmaria (L.) at different stages of succession on a meadow abandoned for 30 years

51%

Falinska K. , Lembicz M. , Jarmolowski A. , Borkowska L.

Polish Journal of Ecology

|

2010

|

tom 58

|

nr 1

EN

Genetic diversity and spatial variation of two populations of Filipendula ulmaria (L.) were analysed at the initial stage (macroforbs) and the late succession stage (forest community) during a 30-year succession on the abandoned meadows in Białowieża National Park. The study demonstrated a high level of genetic diversity in both populations (D = 0.86 and D = 0.79 in the population at the initial and late succession stage, respectively). Significant genetic differentiation was observed at the cross-population level (FST = 0.008, P <0.001). Among 303 ramets in the population at the initial stage 261 genotypes were detected, of which 24 were clonal, and the remaining (237) were unique (91%). In the population at the late succession stage 92 genotypes were detected among 116 ramets of which 10 were clonal, and 82 unique (89%). The results did not confirm a hypothesis that the low level of the population’s genetic diversity should be expected at the late succession stage. Additionally, the study demonstrates that the prolonged clonal spreading does not always result in genetic monotony of a population. It has been demonstrated that the high level of genetic diversity in the population of clonal species F. ulmaria could be the result of temporal changes in life history traits of long-lived genets. The formation of gaps caused by the disintegration of senile genets and the permanent recruitment of seedlings over 30 years of population development reinforce the appearance of new genets. This process was reflected in both populations by the domination of unique genets and spatial pattern of genotypic diversity.

19

Temporal changes in the concentrations of zinc and cadmium in the sedimentary strata of Nozha Hydrodrome, Alexandria, Egypt

51%

Rifaat A. E. , Ahdy H. H. H.

Oceanologia

|

2011

|

tom 53

|

nr 4

EN

This study is concerned with the temporal changes in the levels of zinc and cadmium in the sediments of Nozha Hydrodrome during the past 100 years. Seven sediment core samples, covering the study area, were collected from the bottom of the Hydrodrome. A five-step sequential extraction technique was applied to determine the solid phase concentrations of zinc and cadmium. Zinc gives an idea of the quantities of sewage effluents, while cadmium provides an indication of the amounts of agricultural discharges. The vertical distribution curves show that the average total concentrations of zinc in the sediments increased at a rate of 2.5 μg g−1 y−1 from 1900 to 1950 and at 1.5 μg g−1 y−1 from 1950 to 1990. Since 1990 the zinc concentration in Nozha Hydrodrome sediments has been decreasing at 1.5 μg g−1 y−1. The average total cadmium concentration exhibits a different vertical distribution pattern: it increased at a rate of 0.42 μg g−1 y−1 from 1900 to 1950, after which it became constant from 1950 to 1970. Since 1970 it has been increasing at 0.53 μg g−1 y−1. The ongoing increase in cadmium concentrations in the sediments is due to the increase in agricultural discharges into the Hydrodrome, especially as significant amounts of phosphate fertilizers are used to nourish the soil around the Hydrodrome. The rise in cadmium concentrations since 1900 has been accompanied by a similar increase in zinc concentrations with time resulting from the discharge of untreated sewage into the Hydrodrome. In 1990 a sewerage system and sewage treatment plant came into operation, as a result of which discharges of domestic effluent into the Hydrodrome ceased. Since then the amount of zinc in sediments has been decreasing steadily.

20

Analysis of changes in cyanobacterial and algal flora of selected water reservoirs in Wroclaw between 1878 and 2010 (South-West Poland)

51%

Richter D.

Oceanological and Hydrobiological Studies

|

2013

|

tom 42

|

nr 4