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EN
Salinity and pH play a fundamental role in structuring spatial patterns of physical properties, biota, and biogeochemical processes in the estuarine ecosystem. In this study, the influence of salinity-pH gradient and carbonate system on polychaete diversity in Ennore, Uppanar, Vellar, and Kaduvaiyar estuaries was investigated. Water and sediment samples were collected from September 2017 to August 2018. Univariate and multivariate statistical analyses were employed to define ecological status. Temperature, salinity, pH, and partial pressure of carbon-di-oxide varied between 21 and 30°C; 29 and 39 ppt; 7.4 and 8.3; and 89.216 and 1702.558 µatm, respectively. PCA and CCA results revealed that DO, chlorophyll, carbonate species, and sediment TOC have a higher influence on polychaete community structure. Forty-two species such as Ancistrosyllis parva, Cossura coasta, Eunice pennata, Euclymene annandalei, Lumbrineris albidentata, Capitella capitata, Prionospio cirrifera, P. pinnata, P. cirrobranchiata, and Notomastus sp. were found dominantly in all estuaries. Shannon index values ranged between 1.619 (UE-1) and 3.376 (VE-2). Based on these findings, high levels of carbonate species and low pH have a greater impact on polychaete diversity and richness values. The results of the AMBI Index revealed that stations UE-1, UE-2, UE-3 in Uppanar, EC-1, EC-2 in Ennore indicate “moderately disturbed”, while other stations are under the “slightly disturbed” category. This trend was quite evident in M-AMBI as well.
PL
Polskie pobrzeże jest bogate w jeziora słonawe o charakterze estuariów. Należą do nich jeziora Niziny Gardnieńsko-Łebskiej. Każdy z tych akwenów ma własną specyfikę hydrologiczno-ekologiczną, co skutkuje faktem, że wiedza na temat tych dynamicznych ekosystemów wodnych jest niepełna i wymaga rozszerzenia. W ramach eksperymentu badano bioróżnorodność bakteryjną w jeziorach Łebsko i Sarbsko w różnych porach roku. Materiał do badań stanowił materiał bakteriologiczny, pochodzący z przefiltrowania próbek wody tych jezior. W celu zbadania różnorodności biologicznej wykorzystano łańcuchową reakcję polimerazy – PCR (ang. Polymerase Chain Reaction), połączoną z elektroforezą w gradiencie czynnika denaturującego – DGGE (ang. Denaturing Gradient Gel Electrophoresis). Markerem molekularnym wykorzystanym w badaniach był fragmentu genu kodującego 16S rRNA. Różnorodność biologiczną badano ze względu na gradient zasoleniowy oraz inne zmiany fizyko-chemiczne i biologiczne, wywoływane następującymi po sobie porami roku, oraz występującymi w obrębie zbiornika w zależności od głębokości. Efekty eksperymentu udokumentowano w postaci zdjęć w świetle ultrafioletowym rozdziału w gradiencie czynnika denaturującego produktów PCR, na podstawie których wykonano analizę densytometryczną, obliczono współczynnik podobieństwa Dice’a, indeks bioróżnorodności Shannona oraz utworzono dendrogramy na podstawie algorytmu najbliższego sąsiada. Badania wykazały, że bioróżnorodność zbiorowiska w trakcie trwania eksperymentu nie była stała i wahała się od stosunkowo ubogiej do przeciętnie bogatej genotypowo. Najniższe wartości indeksu Shannona obserwowano latem, co miało związek z fluktuacjami zasolenia i wysoką temperaturą. O tej porze roku zaobserwowano także spadek współczynnika podobieństwa Dice’a w jeziorze Łebsko. Sytuacja taka nie miała miejsca w jeziorze Sarbsko. W projekcie wykazano, iż jezioro Sarbsko ma bardziej stałą różnorodność bakteryjną, na co wskazują mniejsze fluktuacje wartości indeksu bioróżnorodności Shannona. Zaobserwowano nieznaczną zmianę struktury genotypowej w cyklu sezonowym w jeziorze Sarbsko, co obrazują dendrogramy, na których widać stopniowe różnicowanie się zbiorowisk bakterii. Temperatura w różnych porach roku również wpłynęła na różnorodność biologiczną bakterii. Ponadto zaobserwowano związek między bioróżnorodnością i stężeniem tlenu. Podczas eksperymentu nie było zmian w poziomie pH, więc parametr ten nie miał wpływu na bakterie.
EN
The Polish shore of the Baltic Sea is rich in brackish lakes of estuarine character. One of them are lakes of the Gardnieńsko-Łebska Lowland. Each of these reservoirs has its own hydrological and ecological specificity, which results in the fact that knowledge about these dynamic water ecosystems is incomplete and requires further researches. The aim of this work was to study seasonal changes in bacterial diversity in coastal brackish lakes: Sarbsko and Łebsko. Biodiversity was studied for salinity gradient, as well as physicochemical and biological changes (caused by seasons and depth of the reservoir from which the test material was taken). To monitor the genotypic variation of individual microorganisms and estimate biodiversity of the bacterial community in the settlement and to estimate the genotype complexity of the samples PCR-DGGE method (polymerase chain reaction, combined with denaturing gradient gel electrophoresis) was used. The molecular marker used in the studies was a fragment of the 16S rRNA gene. The effects of the experiment were documented in the form of photos in the ultraviolet light of the PCR-DGGE products, on the basis of which densitometric analysis was performed, Dice similarity coefficient and Shannon biodiversity index was calculated, and dendrograms were created based on the nearest neighbor algorithm. The research showed that the biodiversity of the community during the experiment was not constant and ranged from relatively poor to average genotypically rich. The lowest values of the Shannon index were observed in the summer, which was related to salinity fluctuations and high temperature. In the summer, a decrease in the similarity of Dice in the Łebsko lake was also observed. Such a situation did not take place in Sarbsko. The project showed that Sarbsko has a more stable bacterial diversity, which is indicated by smaller fluctuations in the Shannon biodiversity index. It was observed that bacteria genotypic structure has changed slightly in seasonal cycle in tha Sarbsko lake, as dendrograms show. Temperature through the seasons also influence the bacterial biodiversity. What is more relation between biodiversity and oxygen concentration had been noticed. During the experiment there were no changes in pH level and this parameter has not got influence on bacteria.
EN
The effect of climate variability on estuarine water environments was assessed in two systems of the Bay of Biscay, the estuaries of Bilbao and Urdaibai, with contrasting morphology, hydrodynamic features and anthropogenic influence. To that purpose, the main time scales of variability in relevant environmental factors were established along spatial salinity gradients and, using a combination of multivariate and regression analyses, the contribution of each factor to the total variability, as well as the influence of climate factors in the seasonal and inter-annual estuarine environment variations were assessed. The major seasonal modes of variability in the water environments of both estuaries were accounted for by water temperature together with salinity stratification and/or chlorophyll a. This seasonal variability was associated with climate variability, as shown by the relationship with air temperature and river flow. The major inter-annual modes of variability were also accounted for by water temperature, along with dissolved oxygen and/or chlorophyll a in Bilbao, and chlorophyll a and/or transparency in Urdaibai. These were also associated with climate variability, in this case summer air temperatures. Water quality variables, such as dissolved oxygen and transparency, were found to be sensitive to reveal the effect of long term anthropogenic activities.
EN
UV filters are the main ingredients in many cosmetics and personal care products. A significant amount of lipophilic UV filters annually enters the surface water due to large numbers of swimmers and sunbathers. The nature of these compounds cause bioaccumulation in commercial fish, particularly in estuarine areas. Consequently, biomagnification in the food chain will occur. This study estimated the amount of four common UV filters (ethylhexyl methoxycinnamate, EHMC; octocrylene, OC; butyl methoxydibenzoylmethane, BM-DBM; and benzophenone-3, BP3), which may enter surface water in the Gulf of Mexico. Our data analysis was based on the available research data and EPA standards (age classification/human body parts). The results indicated that among the 14 counties in Texas coastal zones, Nueces, with 43 beaches, has a high potential of water contamination through UV filters; EHMC: 477 kg year−1; OC: 318 kg year−1; BM-DBM: 258 kg year−1; and BP by 159 kg year−1. Refugio County, with a minimum number of beaches, indicated the lowest potential of UV filter contamination. The sensitive estuarine areas of Galveston receive a significant amount of UV filters. This article suggests action for protecting Texas estuarine areas and controlling the number of tourists and ecotourism that occurs in sensitive areas of the Gulf of Mexico.
5
Content available remote Water dynamics in estuaries along the Polish Baltic coast
EN
Estuaries are areas where river and sea waters meet. Therefore, the hydrodynamical, hydrochemical, and hydrobiological processes in the estuaries are typical for both environments. The most important processes, which play leading roles in estuaries include the dynamics of water flow, water quality, and the mixing of water of different biochemical characteristics. This paper is divided into two parts. In the first, basic hydrodynamical processes are described and analytical and numerical methods of evaluating them are presented. Part two illustrates these processes using experimental data and the results of mathematical modeling for some estuaries along the Polish Baltic coast.
6
Content available remote Estuaries - a biological point of view
EN
Estuaries are considered adverse environments for many living organisms because of their unstable environmental conditions. Variability in salinity, temperature and oxygen concentration of the water, diverse substrata and geomorphological structures are major contributors to increased ecological stress in estuaries. These variations contribute to the characteristic estuarine spatial and temporal changes of physico-chemical properties, which operate even at small scales. In terms of biology estuaries represent fascinating environments - transition zones between freshwater and marine biomes. Freshwater entering an estuary has a major influence on the ecology of the system, its productivity, diversity and the distribution of organisms, with a high variability of niches favouring an increase of biodiversity and biomass. Many estuarine species/organisms show broad and efficient physiological adaptations (ecotypes) in response to these environmental factors. Under locally specific conditions, even different genetic clades (groups) can be formed. Estuaries serve as vital nursery systems for many fish and unique feeding grounds for migratory birds. On the other hand, estuaries are often seriously degraded habitats, hence providing an ideal environment for combining studies on ecology, nature conservation and human impact.
7
Content available remote Persistent organic polltants (POPs) in estuarine sediments
EN
Persistent organic pollutants (POPs) attract attention as the main threat to human health and environment. The aim of this overview is to provide information on POPs included in the Stockholm Convention, which entered into force last year. Its consequences to environmental analysis, with special emphasis on the estuary - a unique aquatic environment, are presented. In the light of Convention analysis of POPs in estuarine sediments is one of the greatest challenges to face in environmental analysis. This paper presents the origin of the problem of POPs, the list of determined POPs, concentration levels of POPs in estua- ries in different regions of the world, and current methodologies used to determine POPs in estuarine sediments. Finally, some issues are indicated at which the analysts should focus in future.
PL
Trwałe zanieczyszczenia organiczne (TZO) koncentrują ostatnio na sobie uwagę jako związki stanowiące największe zagrożenie dla człowieka i środowiska naturalnego. Niniejszy artykuł dostarcza informacji nt. Konwencji Sztokholmskiej dotyczącej tych związków, która zaczęła obowiązywać w ubiegłym roku, a w szczególności konsekwencji jej wprowadzenia dla analiz naturalnych próbek środowiskowych. zwłaszcza próbek pochodzących z rejonów ujścia rzek. W świetle Konwencji analiza TZO jest jednym z największych wyzwań, przed jakim stoją chemicy analitycy zajmujący się środowiskiem naturalnym. Praca ta przedstawia genezę problemu TZO, przegląd związków, które są oznaczane . w próbkach środowiskowych, podaje ich stężenia w estuariach różnych rejonów świata, a także wymienia aktualnie stosowane metodyki analityczne. Wskazuje też zagadnienia, którym należałoby w przyszłości poświecić szczególną uwagę.
EN
The effect of different concentrations of mercury on the number and respiratory activity of neustonic and planktonic bacteria derived from estuarine Lake Gardno (Baltic Coast, Poland) was studied. The laboratory experiments demonstrated that mercuric ions (Hg^2+) exhibited toxic effects on abundance and oxygen uptake of neustonic and planktonic bacteria. Bacterioneuston and bacterioplankton showed different responses to the mercuric ions. The neustonic bacteria showed higher levels of tolerance to various concentrations of Hg (10-15 mg dm^-3) in the culture medium than the planktonic ones (<10 mg dm^-3). It was found out that the bacteria isolated from freshwater zone of Lake Gardno were more tolerant to the increasing concentration of mercury ions (10-20 mg dm^-3) than bacteria isolated from the seawater and mixed zones of lakes. Non-pigmented bacteria from all layers and zones were more tolerant to the higher Hg^2+ concentrations than pigmented ones. High concentrations (above 8 [mi]g cm^-3) of mercury chloride in the respiratory substrate blocked completely oxygen uptake by neustonic and planktonic bacteria.
EN
Results of an experimental study on the mixing characteristics of the stratified flow inside bottom cavities in salt wedge estuaries are presented and discussed. The experiments were conducted in a laboratory flume where a cavity was formed by placing two consecutive sills over the channel bottom. The cavity was filled with a bottom layer of saline water with a sharp density interface. A constant fresh water discharge was supplied at the upstream end of the flume. An ADV and a fast conductivity probe were used to measure the turbulence and salinity structure inside the cavity. Flow visualizations were made, in addition, to keep track of the position of the density interface inside the cavity. The density interface tilts in the downstream direction with a slope that increases as the local densimetric Froude number, Frd, increases. This slope can be reasonably estimated from a linear analysis of the response of the 2-layer stratified fluid to an interfacial shear stress. The entrainment velocity, or rate of interface deepening due to mixing, decreases as Frd increases, which appears to be the consequence of a decreasing mixing efficiency related to the tilting of the interface. The present entrainment velocity data compares well with existing experimental data and models, validating the latter on an extended range of relevant parameters. By scaling these results to a prototype such as the Valdivia Estuary in Chile, it is concluded that purging of the saline water trapped inside of bottom cavities cannot be completed during a tidal period.
EN
The vegetation, nutrient status and salinity variation of soils from a mangrove swamp in West Africa were studied. Nypa fruticans was the dominant species of the tree layer, in association with Rhizophoraspp, and Avicennia africana. The fern Acrostichum aureum dominated the ground layer. The soils had a high cation exchange capacity (21.8-53.6 me . 100 g'-1), with magnesium and calcium as the predominant cations. Lowest values occurred in Nypa fruticans soils while highest values occurred in Avicennia/Rhizophora mangle soils. Phosphorus values were high for Pandanus and Raphia soil (10.5-18.9 ugml'-1). High levels of total nitrogen (0.13-1.16%) werw restricted to Pandanus soils. Salinity gradients were accounted for by seasonal freshwater inputs and subsurface seepage. Apart fron variation in phosphorus and organic carbon, the nutrient content of the soils showed little relationship to community assemblages and should be related to such habitat variables as tidal inundation, physiography, climate and soil drainage.
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