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E?irdir Lake is the second largest fresh water lake with 482 km2 surface area of Turkey. The lake is an indispensable water source for our country and region because of available water capacity and usage aims such as drinking-irrigation water, tourism, and fishing. However, especially contaminants located in the E?irdir Lake catchment affect the lake water quality negatively in times. Therefore, determination of the water quality of the lake has quite importance for region human health and sustainable usage of the lake. The major factors that control the quality of the E?irdir Lake water are agricultural activities in the basin, water–rock interaction, and domestic and industrial wastes. This study investigates the anthropogenic and geologic impact originated from pollution sources and water–rock interaction in the lake watershed basin to the E?irdir Lake water quality. For this purpose, geological, hydrogeological, and hydrological properties of the lake basin with point and nonpoint pollution sources were investigated. To determine the water quality of the lake, 48 water samples were collected especially from locations representing effects of pollutants in May and October 2009. The analysis results were compared with maximum permissible limit values recommended by World Health Organization and Turkish drinking water standards. The contents of all chemical and physical parameters are higher in dry periods than wet period, and water pollution was observed at discharge points of the streams into the lake. Also, pH, turbidity, potassium, chemical oxygen demand, ammonium, aluminum, iron, and lead concentrations were found to be above drinking water standards. 相似文献
2.
Effects of T-shape groin parameters on beach accretion 总被引：1，自引：0，他引：1
&#x;smail Hakk&#x;
zler Murat &#x;hsan Kmürcü Ali Remzi Birben
mer Yüksek Servet Karasu 《Ocean Engineering》2006,33(3-4):382-403
The effects of various groin parameters (length, head length and opening) and wave parameters (wave height, wave period and wave angle) on the accretion of the area protected by T-shape groins are studied in a physical model. The model studies are performed using regular waves in a basin. A numerical model which depends primarily on a CERC model is employed to examine the effects of some of the above parameters. Good agreement is found in the results of physical and numerical models. The results of a numerical model are compared with field data obtained by deep sounding measurements at Of coasts, Trabzon Province, Turkey. The finding from this study may be employed in designing T-shape groins. 相似文献
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Assessment of trace metal contents in water and bottom sediments from Eğirdir Lake,Turkey 总被引：1，自引：1，他引：0
The concentration of metals (Pb, As, Co, Cu, Ni, Zn, Fe and Mn) was investigated in water and sediment samples of E?irdir Lake. The Lake is the second largest fresh water lake of Turkey and it is used as drinking water in the region. The anthropogenic pollutants are primary sources of trace metals which are negatively affected lake water quality. These negative effects were observed in both lake water and bottom sediments. According to obtained data, Pb, Cu, Ni, Fe and Zn have significant enrichment in sediments samples. In addition, the hydrodynamic model of the lake was determined as effectively for Pb, Co, Cu, Ni, Zn, Fe and Mn accumulations. Also, the effect of anthropogenic pollutants was found to be more dominant than geogenic effect in metal accumulation of the lake bottom sediments. Therefore, anthropogenic pollutants within the lake basin should be consistently controlled for the sustainable usage of the lake. 相似文献
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Investigation of the effects of offshore breakwater parameters on sediment accumulation 总被引：1，自引：0，他引：1
Ali Remzi Birben &#x;smail Hakk&#x;
zler Servet Karasu Murat &#x;hsan Kmürcü 《Ocean Engineering》2007,34(2):284-302
Littoral sediment transport is the main reason for coastal erosion and accretion. Therefore, various types of structures are used in shore protection and littoral sediment trapping studies. Offshore breakwaters are one of these structures. Construction of offshore breakwaters is one of the main countermeasures against beach erosion. In this paper, offshore protection process is studied on the effect of offshore breakwater parameters (length, distance and gap), wave parameters (height, period and angle) and on sediment accumulation ratio, one researched in a physical model. In addition to the experimental studies, numerical model in which the formulae of the sediment discharge (i.e. the formulae of CERC and Kamphuis), was used was developed and employed. The results of the experimental and numerical studies were compared with each other. 相似文献
5.
Debris flow deposits are the principal component of Quaternary continental slope sediments between the north-east Newfoundland Shelf and central Orphan Basin. In seismic profiles, these deposits occur as shingled, elongate, acoustically transparent lenses with their long axes orientated downslope. Deposits of individual flows form positive mounds on the sea floor; subsequent flows were diverted by the pre-existing topography into bathymetric lows between older debris flow deposits. These deposits show a large variation in the area of sea floor covered by individual flows (about 60–1000 km2), average thickness of deposits (9–37 m) and volume of sediment displaced (1–27 km3). The ratio of average thickness to a measure of deposit diameter, termed the aspect ratio, has a threefold variation from 0·0006 to 0·0021. Very low depositional slopes and low aspect ratios suggest relatively low viscosities, probably due to inmixing of water during downslope transport. Stratified sediments form three distinct horizons and are locally interbedded with the debris flow deposits. These are mainly hemipelagic deposits. The slope and rise to the west of the Orphan Basin are constructional in character. The apparent absence of upper slope erosional features and the abundance of debris flow deposits on the slope suggest that the supply of sediment to the continental slope occurred predominantly during times of maximum extent of Quaternary glacial ice. The ice sheet grounding line during several glacial maxima must have been situated at or near the present shelf break, supplying vast amounts of sediment directly to the upper slope. Oversteepening and subsequent slope failures fed material into deeper water. 相似文献
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Purification of diatomite powder by acid leaching for use in fabrication of porous ceramics 总被引：1，自引：0，他引：1
This study presents an investigation of the purification of a raw diatomite by acid leaching conducted in hot solution (75 °C and 5 M HCl) for long periods up to 240 h, evaluates the use of these purified powders in the fabrication of porous materials, and examines their porosities. The treatment for 1 h increased the specific surface area of diatomite from 189 m2/g to 222 m2/g, but the SiO2 content of 78.66% was still low. Material leached for a relatively short time shows an amorphous phase with quartz and plagioclase phases and the plagioclase is removable at longer leaching times during which no disruptive effect on the fine microscopic pores of the particles was observed. Thus, the diatomite based powders have potential use in the fabrication of porous coating as a membrane-separating layer: sintering at a relatively high temperature (1300 °C) still showed a significantly high apparent porosity of 48%. 相似文献
7.
J.T. ANDREWS M.E. KIRBY A. AKSU D.C. BARBER D. MEESE 《Quaternary Science Reviews》1998,17(12):1125-1137
Episodes of glaciation in the region north of Baffin Bay resulted in the erosion of Paleozoic carbonate outcrops in NW Greenland and the Canadian High Arctic. These events are recognized in the marine sediments of Baffin Bay (BB) as a series of detrital carbonate-rich (DC-) layers. BBDC-layers thin southward within Baffin Bay; thus, the contribution of Baffin Bay ice-rafted carbonate-rich sediments to the North Atlantic is probably slight, especially compared with sediment output from Hudson Strait during Heinrich events. We reexamine (cf. Aksu, 1981) a series of nine piston cores from the axis of Baffin Bay and across the Davis Strait sill and provide a suite of 21 AMS 14C dates on foramininfera which bracket the ages of several DC-layers. The onset of the last DC event is dated in six cores and has an age of ca. 12.4 ka. In northern and central Baffin Bay a thick DC-layer occurs at around 4 m in the cores and is dated >40 ka. There were three to six DC intervening events. The youngest BBDC event (possibly a double event) lags Heinrich event 1 (H-1) off Hudson Strait, dated at 14.5 ka, but it is coeval with the pronounced warming seen in GISP2 records from the Greenland Ice Sheet during interstadial #1. We hypothesize that BBDC episodes are coeval with major interstadial δ18O peaks from GISP2 and other Greenland ice core records and are caused by or associated with the advection of Atlantic Water into Baffin Bay (cf. Hiscott et al., 1989) and the subsequent rapid retreat of ice streams in the northern approaches to Baffin Bay. 相似文献
8.
Hydrogeology of karst aquifer systems in SW Turkey and an assessment of water quality and contamination problems 总被引：1，自引：0，他引：1
Aysen Davraz Remzi Karaguzel Iskender Soyaslan Erhan Sener Fatma Seyman Sehnaz Sener 《Environmental Geology》2009,58(5):973-988
The aim of this research is to determine the relationship between groundwater flow and water quality of different ground and
surface water basins in the southwest Turkey. In addition, groundwater vulnerability is assessed taking into consideration
groundwater flow and quality. The autochthonous Beydaglari limestone is the major karstic aquifer in the region. According
to the groundwater level map of alluvium aquifers in the basins, groundwater discharge toward the carbonate aquifer is direct
and indirect. The hydrogeological connection between ground and surface water basins occurs via the karstic aquifer located
at the bottom of the alluvium bottom. In Egirdir lake, water also discharges in the karstic aquifer via karstic sinkholes
at the western border of the lake. In the research area, general groundwater discharge is toward the Mediterranean Sea by
means of autochthonous carbonate system, according to hydrogeological investigations, research of lineament and hydraulic
conductivities. This result is supported by the locations of lineaments and shore springs discharging from the limestone.
In addition, spreading of contaminants via karstic aquifer to great distance has been clearly identified. 相似文献
9.
The aim of this study is to understand the effects of pollution of anthropogenic origin on water quality in Yalvac Basin,
part of the Egirdir Lake catchment. Surface discharge from the basin to the lake is 63 m3/year and underground discharge is 114 m3/year. Possible water pollution is categorized into domestic, industrial and agricultural origin. Domestic and industrial
wastewaters, including effluents from leather tanneries are discharged, without being purified, into Yalvac Stream, which
flows into Egirdir Lake directly or via the drainage canal. Surface waters flowing into the lake are used in winter for irrigation
of agricultural areas. In agricultural areas natural and synthetic fertilizers and pesticides are used extensively. Lake Egirdir
is used as a source of drinking water. Sampling sites were established for surface and underground waters, taking into account
the known point sources of pollution. These sites were sampled in May and October of 2002, and analysed chemically. Cr3+ and Pb2+ concentrations exceed standard limits, meaning that pollution caused by effluent from the tanneries is adversely affecting
the water quality in the lake. 相似文献
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