Geographic patterns of elemental deposition in the Aegean region of Turkey indicated by the lichen, Xanthoria parietina (L.) Th. Fr.

Lichen samples from different parts of the world have been known to accumulate elements to a greater degree than higher plants, if they are exposed to these elements from the atmosphere or from water and sediments. It has been hypothesized that lichens can be used to monitor air pollution around point and area emission sources. Local variation (variation in substrate, age and morphology of lichen samples) of element concentrations would not be large enough to affect the concentration patterns in large areas. We tested this hypothesis in the Aegean region of Turkey, which is very urbanized and industrialized. No such study has been conducted before in this part of the country. A total of 234 samples of the lichen Xanthoria parietina were collected from a 51,800-km2 area. Samples were washed and analyzed by INAA and ICP-AES for 35 elements. The range of the concentrations for most of the elements on a local scale was an order of magnitude lower than for the element concentrations on a regional scale. The mean local coefficient of variance (CV) was found to be 15, providing that the local variation did not affect the concentration of elements in the sampling region. According to cluster analysis, 8 (As, Hg, Pb, Sb, Fe, Mn, Na and K) elements are indicative of important local pollution locations and their zone of impact in the region. By mapping the concentrations of eight indicative elements in lichen Xanthoria parietina of the Aegean region, it was possible to relate deposition to the existence of known sources of pollution in certain areas. Location of pollution sources such as iron-steel plants, and coal burning in the cities, industrial activity and two important coal-fired power plants generally corresponded with locations of highest element accumulations in the lichens.

Determination of metal concentrations in lichen samples by inductively coupled plasma atomic emission spectroscopy technique after applying different digestion procedures.

Three digestion procedures have been tested on lichen samples for application in the determination of major, minor and trace elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V and Zn) in lichen samples collected in Aegean Region of Turkey by inductively coupled plasma atomic emission spectrometer (ICP-AES). The acid mixture of concentrated HNO(3), H(2)O(2) and HF were used. The instrument was optimized using lichen matrix considering RF power, nebulizer pressure, auxiliary flow rate and pump rate. The accuracy of the overall analyses was first estimated by analysis of two certified reference materials. Good agreement between measured and reference values were found for almost all elements. As the second way of determining the accuracy, results obtained from independent analytical techniques (ICP-AES and instrumental neutron activation analysis (INAA)) were compared for all elements by analyzing real samples. Correlation coefficients of two techniques for the elements ranged between 0.70 (Mg) and 0.96 (Fe). Among the three digestion systems, namely microwave, open vessel and acid bomb, microwave digestion system gave the best recovery results. The method detection limit (MDL) was computed using reagent blanks of microwave digestion system since it provides cleaner sample preparation. Detection limit is adequate for all elements to determine the elements in lichen samples. The precision was assessed from the replicate analyses of reagent blanks of microwave digestion system and was found to be less than 1.5% relative standard deviation (R.S.D.).

Gaseous and particulate air pollutants in the Northeastern Mediterranean Coast.

The concentrations of sulfur dioxide (SO2), ammonia (NH3) and particulate matter were measured for a 6-month period and the concentration of gas phase nitric acid (HNO3) was measured for a 1-month period in the North-eastern Mediterranean atmosphere (Küçük Calticak, Antalya) using a 'filter pack' system that was developed and optimised in our laboratory. Among all the gas phase pollutants, HNO3 had the lowest concentration (0.42 microg m(-3)) followed by ammonia. Most of the measured parameters showed variation in time depending on strengths of source regions and meteorological conditions. Nitric acid is found mostly in particulate form, but gas to particulate partitioning of SO2 shows seasonal variation. Wind trajectory analyses indicate that the major contribution to the observed concentrations come mostly from Eastern Europe and Blacksea regions as well as the southern sector.

Sampling and analysis of gaseous pollutants and related particulate matter in a Mediterranean site: Antalya-Turkey.

Gas phase pollutants. nitric acid (HNO3), sulfur dioxide (SO2), ammonia (NH3) and particulate matter, were collected simultaneously for six months from the Eastern Mediterranean atmosphere (Küçük Calticak, Antalya) using a "filter pack" system developed in our laboratory. This system is a combination of chemically treated filters for the collection of gaseous ammonia and sulfur dioxide. and Teflon and nylon filters for the collection of particulate matter and gaseous nitric acid, respectively. After pre-treatment, Teflon, nylon and the treated filters were analyzed by ion chromatography (IC) for major ionic species: SO4(2-) NO3- and Cl, and by colorimetry for NH4+ ion. Comparison of the SRM (Standard Reference Material) results with measured concentrations showed a good precision for the IC analyses: 3%, 1% and 2% for Cl-, NO3 and SO4(2-) ions. respectively. Most of the measured parameters were log-normally distributed. Chloride ion had the highest (4.30 microg m(-3) and HNO3 had the lowest (0.42 microg m(-3)) concentrations. Total acidity in the Eastern Mediterranean is controlled by 47.7% HNO3 and 52.8% by H2SO4. Ammonium, nss-SO4(2-) (non-sea salt sulfate) and NO3 did not show a strong correlation, (r = 0.4), which means that ammonia is not the major neutralizing species in the Eastern Mediterranean atmosphere.

Atmospheric pollutants in Uludag National Park.

Gas phase pollutants and major ions were measured in the Sarýalan region of Uludag Mountain, which is experiencing severe deforestation. Short- and long-term trends in the concentration of the gas pollutants were computed from the samples obtained in order to identify the source of these pollutants. The higher concentration of O3 during summer months was consistent with the higher photochemical production from precursor gases (NOx) with increased solar flux. The diurnal pattern of O3, NO, NO2 and TSP describes a photochemical smog scenario. A lower pH in aerosols associated with high levels of SO4(2-) and NO3- is an indication of acid deposition. Wind sector analysis revealed that the major contributing source regions are north and south of the sampling site, that is, the city of Bursa, local industries, and the Orhaneli power plant.

Measurements of SO2, NO X and SPM in an industrial area at the Aegean coast of Turkey.

Data from continuous measurements of SO2 NO x , suspended particulate matter (SPM) and meteorological parameters at seven sites around a highly industrialized region in the Aegean coast of Turkey, between July 15, 1991 to July 31, 1992 were used to evaluate spatial and temporal variations of air quality parameters. Low annual averages and insignificant differences between day and night concentrations were observed at stations far from sources. At stations close to sources, annual average concentrations were high and diurnal patterns were significant. Annual average SO2 and SPM concentrations in all stations used the 'Krigging' technique to assess the impact of industries on air quality in the surrounding airshed. Results have demonstrated that Turkish air quality standards for SO2 were exceeded in a circle with a radius of 4 km and which was centered on the petrochemical complex and refinery. Similarly, standards for SPM were exceeded in a circle with a radius of 1.2 km and which was centered on the ironwork plants. Both SO2 and SPM showed well defined diurnal variations, particularly in stations close to sources. The SO2 concentrations showed a maximum during day-time, while SPM concentrations peaked after midnight. Although annual average SO2 and SPM concentrations were highly variable depending on distances between stations and sources, background concentrations of the same pollutants, calculated by stripping episodes from data, did not change significantly from one station to another. Long range transport and resuspension of local soil were suggested as sources of background SO2 and SPM, respectively. The difference between observed and background concentrations of SO2 and SPM in each station was related to the impact of industries on air quality at that particular site.