Air Pollution Effects on Forest Trees in Balikesir, Turkey

Air pollution has become an actual problem in Balikesir because of rapid urbanisation and increasing of the polluting sources. Air pollution problems occur under the unfavorable meteorological conditions which increase in frequency of occurrence in winter due to use of low quality lignite coals for heating. The 'Protection of Air Quality' in Turkey dated 1986 is based on the human health criteria. But the critical limit values are lethal for the forest trees as far as SO sub(2) is concerned. The field observations showed that leaves of the trees have yellow spots indicating acid burns in Balikesir. This study aims at determining the relationships between the SO sub(2) concentrations in the air under selected climatic conditions, and the effects of air pollution on forest trees in Balikesir. Samples of leaves were collected from the City Parks in Balikesir, Degirmenbogazi forested area located 10 km far from Balikesir on the Balikesir-Bursa highway, and from the forestation areas near the Balikesir-Edremit highway. Sulfur contents of the leaves were very high especially in the city (2650-5300 mu g m super(-3)). Samples from other areas had values lower than this range but above the usual values (850-3612 mu g m super(-3)). The diameter increments of the trees were found to be lower and these results clearly showed the adverse impacts. Negative correlations were found between these sulfur concentrations and the daily mean temperatures and wind speeds. Positive correlation was seen between these concentrations and pressures, humidities. Emission sources must be controlled in order to safeguard the forests which protects the soil, facilitate water production, assimilate carbon dioxide in air and produce oxygen. It must be considered that the problems are not only regional but have a global identity.