Bacteriological indicators of anthropogenic impact prior to and during the recovery of water quality in an extremely polluted estuary, Golden Horn, Turkey

Five years of monthly data of indicator bacteria from 1998 to 2002 were evaluated to find out the changes in water quality during the rehabilitation of the Golden Horn, an estuary severely polluted from industrial and domestic discharges since the 1950s. Surface fecal coliform was above 10(6) CFU/100 ml at the inner part in 1998. Following the achievement of healthy water circulation and control of most surface discharges, fecal coliform and fecal streptococci counts decreased below 10(3) CFU/100 ml in the summer of 2002. However, the decrease was interrupted by sudden shifts in rainy periods. Runoff, enhanced by domestic inputs during rainfall, has become the main factor influencing water quality in the estuary today. Increasing values of fecal coliform were observed during periods of low salinity, pH, dissolved oxygen and high ortho-phosphate, whilst decreasing values were detected during high salinity, pH and dissolved oxygen and low ortho-phosphate periods. Striking changes were observed within five years, promising that even an anoxic water body can turn into a recreational area with appropriate treatment.     

Effect of organic solvent type on the removal of nitrate ion using liquid membrane technique

In this study, the removal of nitrate ions from aqueous solutions with liquid membrane technique has been investigated for different organic solvent types in which solubilized tetradecyl trimethyl ammonium bromide (TDTMABr) as carrier. n-butyl alcohol, chloroform, and mixture of chloroform + n-hexane (n-hexane 85% + chloroform 15%) were used as organic solvent. Kinetic parameters (k _1d, k _2m, k _2a, t _max, R _m^max, J _m^max, J _a^max) were calculated from obtained data. time R _a values of mixture, butyl alcohol, and chloroform are 0.81, 0.78, and 0.55, respectively. Similarly R _d, R _m, and t _max values of the mixture equal to 0.14, 0.04, and 87.92 min, respectively. This behavior of the system shows the organic solvent type is an effective parameter on separation yield. It can be concluded that the mixture is the most effective organic solvent type among the investigated ones, because liquid membrane systems should be operated within the range of having the R _m, R _d, and t _max values are minimum while R _a values are maximum.     

糖蜜酒精废液生化法的研究进展

介绍国内外糖蜜酒精废液生化法的研究现状 ,指出单级工艺很难达到排放标准 ,需要二段以上工艺才能使废液达标排放。     

祁连与北秦岭结合部位陇山岩群与秦岭岩群对比讨论

发育于陇山地区 (祁连山 )的变质基底岩系—陇山岩群 ,其岩石组合、原岩建造、岩石化学、地球化学、变质作用及构造环境与北秦岭造山带秦岭岩群非常相似 ,属同一大地构造带 ;被后期构造改造位错形成现在状态     

Correlation between ground failure and soil conditions in Adapazari, Turkey

Ground failure in Adapazari, Turkey during the 1999 Kocaeli earthquake (M_w=7.4) was severe. In four central downtown districts, where more than 1200 buildings collapsed or were heavily damaged, hundreds of structures tilted and penetrated into the ground due in part to liquefaction and ground softening. Based on a multi-institutional subsurface investigation program, soil conditions along four lines in which ground failure was surveyed after the earthquake are classified into four generalized subsurface site categories. This classification is primarily based on the presence or absence of shallow and intermediate depth liquefiable soils. Observations of ground failure are found to correlate well with site categories that are susceptible to liquefaction according to current state-of-the-art methods without strict adherence to the Chinese criteria. Soils that liquefied were found to meet the liquid limit and liquidity index conditions of the Chinese criteria. However, soils that liquefied did not typically meet the clay-size condition for liquefiable soils by the Chinese criteria.     

The greatest soda-water lake in the world and how it is influenced by climatic change

Global wanning resulting from increasing greenhouse gases in the atmosphere and the local climate changes that follow affect local hydrospheric and biospheric environments. These include lakes that serve surrounding populations as a fresh water resource or provide regional navigation. Although there may well be steady water-quality alterations in the lakes with time, many of these are very much climate-change dependent. During cool and wet periods, there may be water-level rises that may cause economic losses to agriculture and human activities along the lake shores. Such rises become nuisances especially in the case of shoreline settlements and low-lying agricultural land. Lake Van, in eastern Turkey currently faces such problems due to water-level rises. The lake is unique for at least two reasons. First, it is a closed basin with no natural or artificial outlet and second, its waters contain high concentrations of soda which prevent the use of its water as a drinking or agricultural water source. Consequently, the water level fluctuations are entirely dependent on the natural variability of the hydrological cycle and any climatic change affects the drainage basin. In the past, the lake-level fluctuations appear to have been rather systematic and unrepresentable by mathematical equations. Herein, monthly polygonal climate diagrams are constructed to show the relation between lake level and some meteorological variables, as indications of significant and possible climatic changes. This procedure is applied to Lake Van, eastern Turkey, and relevant interpretations are presented.     

Impacts of Human Activities on Groundwater Quality of an Alluvial Aquifer: A Case Study of the Eskişehir Plain, Turkey

Hydrochemical and water-quality (except biological) data obtained through a two-year sampling and analysis program indicate that the highest concentrations of groundwater pollution occur in the central and eastern parts of Eski?ehir city. Groundwater quality degradation outside the urban area results from agricultural activities. The most serious pollution of groundwater in the Eski?ehir plain is from nitrogen compounds (ammonia, nitrite, and nitrate). The concentrations of ammonia, nitrite, and nitrate of the 51 surveyed water wells range from 0.01–1.65 mg/L, 0.01–1.80 mg/L, and 1.1–257.0 mg/L, respectively. Orthophosphate concentrations in groundwater range from 0.01–1.25 mg/L. Considerable seasonal fluctuation in the groundwater quality was observed. In general, the groundwater quality in wet seasons was better than the quality in dry seasons.