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Sandy sediments coming from three beaches of the southern Baltic Sea were collected and analyzed. Investigated beaches were divided according to strength of anthropogenic impact and degree of sheltering. The first beach was situated in Ustka on the eastern side of the mouth of the Słupia River, second in Czołpino and the last one in Puck. Core sediment samples were collected seasonally, depending on the influence of the sea water on the examined sediments. At each station, surface sediments (0-5 cm) were collected as well as sediments at the depth of 10-15 cm. The general content of organic matter, proteins, lipids, carbohydrates, organic carbon and total bacterial number were determined. The results of the conducted tests reveal, that anthropopressure, degree of sheltering, the depth where the collected sediments were taken and the direct influence of the sea water on the sediments have impact on the chemical composition of organic matter and bacterial number in beach sediments.
The sediments of the beaches along the central coast of Tamil Nadu from Pondicherry to Vedaranyam were studied for their textural variation. 108 sediment samples collected from the low-, mid-, and high-tidal zones, as well as the berms and dunes of different beach morpho-units were analysed. The study area was divided into three sectors (northern, central and southern) on the basis of prevailing energy conditions and oceanographic parameters. The poorly sorted, negatively skewed, coarser sediments of the northern sector are indicative of denudational processes taking place there. Medium-to-fine, moderately-to-well sorted, positivesymmetrically skewed sediments dominate the central sector, probably as a result of the influence of palaeo-sediments deposited by rivers from inland as well as by waves and currents from offshore. Fine, poorly sorted, positive-symmetrically skewed sediments dominate the southern sector, highlighting depositional processes. Linear Discriminant Function Analysis (LDF) of the samples indicates a shallow marine environment origin for all the three sectors. These results show that reworked sediments, submerged during the Holocene marine transgression, are being deposited on present-day beaches by waves, currents and rivers in the study area.
The investigations of the chemical composition of sands were conducted on the beach in Ustka and Czołpino. The Ustka is a typical tourist town and Czołpino is located in the Slovinski National Park away from urban or rural areas. The beach sediments in Ustka contain much more organic matter, nitrogen and phosphorus compounds as well as calcium carbonate than analogous deposits in Czołpino. The effect of sea water was manifested in the high content of organic matter in places having permanent contact with sea water. The content of the organic matter increased together with with the depth of settlings in these places. However more organic matter in surface layers was observed in regions more distant from the sea, because penetration of organic matter into the sediments is possible during precipitation. The concentration of ammonia nitrogen in the analyzed beach deposits increased with depth, what probably results from the lower oxygen content in deeper layers. It was confirmed that organic matter in sands of the beach in Czołpino is of natural origin, while in Ustka it is primarily of anthropogenic origin.
Scanning electron microscopy was employed for the investigation of bacteria living on sand grains in a sandy marine beach in the Gulf of Gdansk (southern Baltic Sea). Bacteria colonize the sand grains; individual topography and shape of the grains were decisive for the colonization. Grains of diverse topography characterised by a great irregularity of shape were preferred, and protected surface sites were favoured. Many of the attached bacteria were found to produce polymer secretions; entire colonies attached by means of polymer nets were observed. A significant morphological diversity of bacteria in the vertical profile of the beach was determined. Bacteria inhabiting the sand grains showed the ability to reproduces.
On nine beaches and two transects in the surf zone along the Dutch coast the presence of benthic macrofauna was studied in relation to basic abiotic characteristics. According to Short’s classification system, Dutch beaches are mesotidal and dissipative (Ω = 8.6), and the RTR is low (1.52–1.27), which means that they are not tide-dominated. BSI ranged from 1.4 to 1.1 for the northern and western Dutch coasts respectively and had an overall value of 1.2. The rates of exposure of the beaches varied between 8 and 12, and are therefore regarded as sheltered to moderately exposed. The Dutch beaches display a geographical trend in beach types. Those of the Wadden Sea islands in the northern part of the Netherlands are dissipative, flat, fine-grained, and host high densities of many species of benthic macrofauna. The beaches along the western Dutch coast are less dissipative, steeper, with a higher mean grain size; the species diversity and abundance there are lower. Species diversity and abundance on the beaches increase from the high- to the low-water line. The maximum number of species was found between 0 and –1 m relative to the mean tidal level. The abundance peaks just above the mean tidal level, while the biomass reaches a maximum at the mean tidal level. Species diversity and abundance are low in the surf zone, but increase towards deeper water. Species numbers are high and the abundance is very high in the trough between the two bars. The relation between the diversity and abundance of macrobenthic species on the one hand, and the sediment composition, water column depth, and position between the bars on the other show a clear pattern of zonation for the beach, surf zone and near-shore: (1) a supralittoral zone with insects and air-breathing crustaceans, (2) a midshore zone, with intertidal species, (3) a lower shore zone, whose species extend into the shallow surf zone, and (4) a zone of sublittoral fauna in the trough between the two breaker bars within the surf zone.
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Run-up of dispersive and breaking waves on beaches

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Transformation of waves on sandy beaches, their breaking, set-up and run-up are the main factors contributing to fluctuations in the water table and groundwater flow. In this paper, the run-up mechanisms have been studied using analytical models. In contrast to the standard models, the waves approaching the shoreline are assumed to be dispersive and the equivalence of the non-linear and linear solutions for the extreme characteristics of wave run-up, such as the height of maximum run-up and the velocity of run-up, are used. A linear system of equations for the run-up of breaking waves is developed. This system is based on the application of the mild-slope equation in the deeper area, where waves are dispersive, while the linear equations of shallow water are applied close to the shoreline, where the water depth is a linear function of distance. The dissipation factor in the shallow water equation has been formulated using its resemblance to the mild-slope equation for a non-permeable sea bottom. Application of the method is illustrated for various bottom profiles and wave characteristics, and theoretical results compared well with experimental data. These solutions of the run-up phenomena will assist future studies on wave-induced beach groundwater flow.
A brief investigation of light minerals along the beaches between Valinokkam and Tuticorin has been carried out for the first time along the Southern Tamilnadu coast in order to discover the provenance of the sediments. The study spotlights a wide variation in light mineralogy along the three zones of the investigated area (Valinokkam, Vaippar and Tuticorin). A higher percentage of quartz is reported from the Valinokkam (48.34 to 68.63%) and Tuticorin zones (55.66 to 73.05%) than from the Vaippar zone (40.24 to 60.77%). The trend with regard to the maturity index is similar, with appreciably higher values in Valinokkam (1.15 to 1.89) and Tuticorin (1.61 to 1.94) than Vaippar (0.79 to 1.39). Morphological analysis of quartz grains shows a higher order of sphericity and roundness values in Valinokkam and Tuticorin as compared to Vaippar. Moreover, the surface texture of quartz grains observed with the aid of scanning electron microscope (SEM) photographs reveals the presence of different depositional environments and the multiple origin of beach sediments in the study area. From the present study of the light mineralogy of beach sediments, it is inferred that the source of the sediments is a mixed type: igneous and metamorphic crystalline rocks, together with palaeosediments.
The results of an eight-year study undertaken in years 1999-2006 on Sciomyzidae of the saline habitats of the Polish coast are reported. In the paper, 12 species, among which 9 are new for beaches and brackish areas of the coastal type, are presented. Besides this, similarity of types of habitats, dominance structure and phenology of Sciomyzidae in the sampling plots are discussed.
Psammon habitats like freshwater sandy shores are the peculiar sites due to high fluctuation of physico-chemical conditions and due to the specific composition of the organisms communities distributed along the horizontal pattern related to the wave action. Taxonomic composition, numbers and biomass of phytopsammon were studied in hygroarenal (shore sand beach wetted by lake waves) of the small beach of the eutrophic Lake Mikołajskie (area 498 ha, max. depth 26 m) (Masurian Lake District, Poland). Samples were collected on one occasion (26 June 2003) from 30 sampling stations distributed parallel to lake shore along 10 m line at three different distances (sampling points A, B, C) from 0 to 60 cm from water line. The studies showed distinct horizontal distribution of psammon algae. Their numbers and biomass varied from 2.22 to 31.85 × 03 cm–3 of sand and from 0.49 to 4.69 μg cm–3 of sand, respectively. Mean numbers in all sampling distances were very similar, while the biomass increased with increasing distance from water line. Cyanoprokaryota, among which Oscillatoria spp. were most numerous species, dominated in the numbers, whereas Bacillariophycea (mainly Stephanodiscus hantzschii Grun. and Fragillaria spp.) constituted significant proportion of the total algae biomass. There were no significant correlations between abundance of algae and size fractions of sand. Among taxonomic groups, only the biomass of Cyanoprokaryota showed positive correlations with trophic parameters (TP, TN). The studies did not show any correlations between phytopsammon and the abundances of ciliates and rotifers, suggesting that different environmental factors as well as organisms of the higher trophic levels may play a decisive role in the development and horizontal distribution of algae in hygroarenal of the beach of the eutrophic lake.
This study was carried out to determine the water quality of the beaches at Matrouh, south-eastern Mediterranean Sea, Egypt, by studying environmental variables as well as phytoplankton abundance and community structure. Surface water samples were monitored from a series of beach sites over a period of five seasons during 2009–2010. A total of 203 phytoplankton species were identified from seven algal divisions. Seasonal differences in the quantitative and qualitative composition of the phytoplankton communities in the different sites were marked. Nutrient concentrations and phytoplankton abundances were found to be poorer than those of many other areas along Egyptian coast. The Shannon-Wiener Diversity Index classified Matrouh water as being between clean and moderately polluted, whereas the WQI demonstrated that it was between good and excellent. It can be concluded that the index based onWQI is currently more suitable than the phytoplankton species index for assessing the quality of the water of the Matrouh beaches.
The aim of this study was to identify empirical relationships among 12 water chemistry parameters, microcystins, and coliform bacteria at four beaches in Lake Winnipeg, Canada. While microcystin fluctuations were not synchronized among the different sites, concentrations were marginally correlated with concurrent nitrate levels at individual sites, but lagged more significantly behind soluble inorganic phosphorus, and inversely behind the nitrate-N/soluble phosphorus ratio (NPR). Microcystins were also inversely correlated with copper, which was used as an algaecide in the lake. Total coliform bacterial counts (TC) were significantly greater at times of increased turbidity, temperature, and higher inorganic phosphate and dissolved organic matter. TC were also inversely correlated with NPR.
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