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EN
The potential of seventeen marine seaweed extracts (five Chlorophyceae, six Pheophyceae, six Rhodophyceae) was investigated to determine their antibacterial activity, aiming to evaluate their viability in pharmaceutical applications. The assessment of their bioactivity involved utilizing crude extracts from dried samples against five Gram-positive bacteria, one Gram-negative bacteria, yeast, and fungus using the disk diffusion technique. These samples were collected from Oualidia, situated along Morocco’s Atlantic coast. Out of the diverse macroalgae studied, 36% of the extracts exhibited activity against at least one of the tested microorganisms. This outcome strongly supported the notion of leveraging algae extracts as a promising source of antibacterial compounds. In particular, extracts from Cystoseira humilis, Bifurcaria bifurcata and Asparagopsis armata showed zones of inhibition greater than 17 mm. Purification of the compounds responsible for the inhibitory activity against several types of C. humilis microorganisms was performed using chromatography and thin layer chromatography.
EN
In compliance to the estuarine areas having access to the sea and riverine water, Miani Hor, a coastal water body in Lasbela, Pakistan could be categorized as a lagoon due to its shallowness, elongation to the coast, connectivity with the adjacent Sonmiani Bay and occasional receiving of rainwater. In the present paper, Miani Hor was studied to understand its dynamics, and to compare it with the categories of lagoons as proposed by Kjerfve (1986). The result of the field data of water quality and water movement as well as satellite imagery of different years show that this is a tide-dominated lagoon with a single inlet, and it was formed in the last glaciation period. Its only inlet is stable and remains open even during the period of high energy waves offshore Sonmiani Bay that generate strong littoral drift. The data suggest that unlike choked lagoons, as proposed by Kjerfve (1986) for classification of the single-inlet lagoons with limited tidal influence, Miani Hor has a small (0.08) ratio of the channel cross-sectional area to the lagoon surface area. The lagoon channel filters out high energy waves but allows strong tidal signals to penetrate the lagoon. The paper suggests that Kjerfve (1986) classification requires modification by incorporating another class “relaxed lagoons” for the single inlet tide-dominated lagoons.
EN
This article addresses the southern sector of the Curonian Spit, the largest coastal barrier of the Baltic Sea. A comparative analysis of the deposits that make up parts of the Curonian and Vistula Spits is given. The detailed analysis of the geological and geomorphological structure of the southern part of the Curonian Spit suggests that, within this sector, it is not a sedimentary barrier created by wave action and Aeolian processes in the Holocene, but a part of a pre-Holocene fluvioglacial plain. Field work has shown that the ancient alluvial or fluvioglacial plain is in the lagoon shore of the Vistula Spit.
EN
The aim of this work was to find out whether the difference between the central Vistula Lagoon (the southern Baltic Sea) and the western lagoon was reflected in the relationships between nutrients and phytoplankton during one-day hot summer conditions when the water temperature exceeded 20°C. Significant differences in Soluble Reactive Phosphorus (SRP) and Dissolved Inorganic Nitrogen (DIN) concentrations, and also in the biomass of the dominant phytoplankton assemblage of Cyanoprokaryota, were noted in the studied parts of the lagoon. No such differences were found for the nitrogen to phosphorus ratio (N:P) or for the biomasses of Bacillariophyta and Chlorophyta. The very low values of N:P (on average 2.8 and 3.4) indicated strong nitrogen limitation. The Correspondence Canonical Analysis (CCA) showed that the central part of the lagoon could be defined as positively related to DIN and to N:P, and western part could be characterized by correlation with temperature, dissolved oxygen and SRP concentrations. Competition for the limited resources of Dissolved Inorganic Nitrogen in the western, shallower part of the lagoon was in favour of Cyanoprokaryota, to the detriment of other phytoplankton assemblages. In contrast, the Cyanoprokaryota biomass in the central part of the lagoon, where DIN concentrations were increased, was lower, and Bacillariophyta in particular prospered at their expense. Here, the competition for Soluble Reactive Phosphorus was not so clear-cut.
PL
Narastająca urbanizacja miast wiąże się z deficytem miejsc wypoczynkowych. Koniecznością staję się tworzenie miejsc rekreacji dla przybywającej ludności. Jednym ze sposobów rozwiązania problemu jest przekształcanie terenów zdewastowanych w obszary zielone. W artykule autor zwraca szczególną uwagę na potencjał krakowskich Bagrów oraz przedstawia możliwość zagospodarowania terenu dla celów turystyczno-rekreacyjnych.
EN
The increasing urbanization of cities is associated with a deficit of holiday destinations. It has become necessary to create increased forms of recreation for visitors and to convert the devastated areas into green areas. The author is presenting a plan of revitalization with regards to the potential of Bagry lagoon in Krakow.
6
Content available remote Water column conditions in a coastal lagoon near Jeddah, Red Sea
EN
Water column conditions in a lagoon near Jeddah are investigated on the basis of changes in potential energy. Three major factors including balance of surface heat at the air-sea interface, wind and tidal mixing are considered. A negative potential energy change dv/dt will develop stratification, whereas positive dv/dt will tend to mix the water column. The tidal effect is greater in summer with wind mixing showing no great variations. The buoyancy effect of the heat balance at the surface is negative from April to October. This negative buoyancy effect will tend to develop stratification but the positive contributions of wind and tide counteract this and the water column remains mixed except in September and October, when a weak stratification may develop. Generally, the water column remains practically mixed throughout the year. The change in heat content of the water column from mid-April to mid-September is about 3.3 × 10^8 J. During this period the net heat input at the air interface is about 2.0 × 10^8 J, which is about 40% less than the heat content of the water column, showing that the heat is advected towards the central area from the shallower periphery of the lagoon.
EN
In this study we present calibration/validation activities associated with satellite MERIS image processing and aimed at estimating chl a and CDOM in the Curonian Lagoon. Field data were used to validate the performances of two atmospheric correction algorithms, to build a band-ratio algorithm for chl a and to validate MERIS-derived maps. The neural network-based Case 2 Regional processor was found suitable for mapping CDOM; for chl a the band-ratio algorithm applied to image data corrected with the 6S code was found more appropriate. Maps were in agreement with in situ measurements. This study confirmed the importance of atmospheric correction to estimate water quality and demonstrated the usefulness of MERIS in investigating eutrophic aquatic ecosystems.
EN
Seasonal changes in the morphometric and physiological parameters of the cockle Cerastoderma glaucum (Bivalvia) from the Baltic Sea (GD), the North Sea (LV), and the Mediterranean Sea (BL) were investigated. The cockles from GD were much smaller than those from other populations due to osmotic stress. The female to male ratios did not differ significantly from 1:1. The northern populations (GD, LV) had a monocyclic reproductive pattern, whereas the southern population (BL) seemed to reproduce throughout the year. Seasonal changes in the contents of biochemical components appeared to be correlated with changes in trophic conditions and the reproductive cycle. Protein content was the highest in spring for all the populations. The highest lipid contents and lowest carbohydrate contents were noted in GD and BL in spring, while no marked differences were noted among seasons in LV (probably because the data from both sexes were pooled). Respiration rates in GD were the highest among the populations, which could have been due to osmotic stress. High metabolic rates expressed by high respiration rates in GD and LV in spring and autumn could have resulted from gamete development (in spring) and phytoplankton blooms (in spring and autumn).
EN
The authors find no arguments that would justify application of the term “estuary” to the area of the Odra River discharge into the Baltic Sea. The physiography, geology, and hydrology of the Odra river mouth show that the area possesses many more characteristics typical of flow-through coastal lagoons than those of estuaries. Of key importance in this respect is the Szczecin Lagoon, an extensive, shallow water body separated from the open sea by a barrier intersected by three narrow and long straits. The lagoonal nature of the area is demonstrated also by its geological history.
EN
The aim of the present work was to investigate the helminth fauna of commercially caught gobiid fishes (Zosterisessor ophiocephalus, Neogobius melanostomus, N. fluviatilis, N. syrman) of the Budaksky Lagoon. The studied fish harbored nine parasite species that include three Holarctic species, one Euro-Siberian, one Cosmopolitan species, one Boreo-Atlantic species, one Mediterranean species, and two Ponto-Caspian ones. The most widespread species were: Cryptocotyle lingua, C. convacum, Acanthocephaloides propinquus. Two Ponto-Caspian cestod species: Proteocephalus gobiorum, Ligula pavlovskii are specific for gobiids. Possible reasons of the infection variability were discussed. Eight species of helminths have been recorded for the first time in the Lagoon.
11
Content available remote O dynamice lagun liberyjskich w czasie pory suchej
EN
Paper reports findings on hydrological regime of Liberian lagoons during dry season collected during over two years staying in Liberia. While traveling along shoreline in Liberia one has to cross several rivers' mouths, which are very shallow during a dry season. Hydro-meteorological processes and sea activity control process of closing and opening of rivers mouths. Although the closure of the mouth of big rivers has never been recorded, such tendency is observed at the end of dry season. In his way along seashore, one is passing by a countless number of coastal lagoons with their own drainage area. The lagoons are in the various stage of development in respect to sea-lagoon communication: Two-way communication. It is a rule during rainy season. Downstream communication only. Sea is open for lagoon, while lagoon is closed for the sea in the advanced stage of the construction of sand bar, excluding short period of high tides. Upstream communication only. The sand bar is so high that it prevents lagoon from reaching the sea. No water exchange between sea and lagoon. Liberian lagoons show unusual phenomenon of thermal inversion. There are several pits in lagoon where the temperature of the bottom layer is 3-6°C warmer tan the surface layer. The behavior of the Po river during dry season is described. The river of such size spans a gap between big Liberian rivers discharging into the sea and coastal lagoons with small catchment and in particular between fluvial and stemmed lagoons. The presented description of lagoon dynamics in respect to storage of mass, energy as well as thermal and salinity stratification shows that there are still some new challenging scientific problems, which calls for multidisciplinary investigation.
EN
The round goby Neogobius melanostomus and the grass goby Zosterisessor ophiocephalus are most widespread fishes of the Tuzly?s group salty lagoons - Alibey and Burnas (North-Western part of the Black sea, Ukraine). The helminthofauna of these fishes consists of six species of parasites: Cryptocotyle lingua, C. concavum, Acanthocephaloides propinquus, Telosentis exiguus, Contracaecum microcephalum, and Cucullanellus minutus. Trematods of the genus Cryptocotyle, acanthocephalans A. propinquus, and larvae of nematods C. microcephalum are reported from this water area for the first time; the latter from gobies for the first time. The interrelation between infection of fishes and biology of helminthes and their host is discussed. This is the first study containing the complete information on the parasite fauna of the Lagoons.
EN
Feeding preferences of the round goby and mushroom goby from the Odessa Bay (areas with civil engineering works) were studied. Two goby species were observed to choose different dietary items in dependence of the season and place of fishery. The mushroom goby chose Nereis succinea more intensively than the round goby.
EN
Estuaries and lagoons are specific geological environments existing on contact of the land and the sea. There are many definitions and classifications of these environments, which depend on point of view of different research disciplines. Such situation causes a lot of disagreements between specialists such domains as hydrology, geology, geomorphology, etc. Author's intention was to compile and compare of various data about these transitional geological environments. Some information were compiled regarding definitions, classifications and such geological features as hydrodynamics, lithodynamics, sedimentary processes and geochemistry of sediments of estuaries and lagoons.
EN
Estuaries and lagoons are specific geological environments existing on contact of the land and the sea. There are many definitions and classifications of these environments, which depend on point of view of different research disciplines. Such situation causes a lot of disagreements between specialists such domains as hydrology, geology, geomorphology, etc. Author's intention was to compile and compare of various data about these transitional geological environments. Some information were compiled regarding definitions, classifications and such geological features as hydrodynamics, lithodynamics, sedimentary, processes and geochemistry of sediments of estuaries and lagoons.
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