بررسی تاثیر آلودگی هوا و فشارهای زیست محیطی حاصله (عوامل غیر زنده) بر روی پوشش گیاهی پارک جنگلی چیتگر

Investigation on air pollutant impacts on vegetation cover of Chilgar Parkland was carried out during the period 1994 to 1998. Iearly 40 percent of small factories and iridustrial units are based around [his area. Lab analysis of samples of pine trees indicated that. lead uptakes on fold higher for pine trees close to high way compare to farther side trees. Also seasonal sampling in pi ne trees showed that spring uptake of lead in pines near freeway is more than 4 fold of Pb uptake through intrinsic pine trees sampling bands. Comparison of seasonal pine needles sampling showed that spring Pb uptake is 1.5 times higher than summer Pb uptake. Amounts of Pb in summer pine sampl~s are near to 20 p.p.m in pale-color trees. which is close to the amount of spring Pb uptake. Also summer semi faded spring is 2.5 fold higher than I;lsh and healthy trees- in summer. To study rain quality indexes automatic rain sampl~ls as Wet Deoosition were used. Measured elements in rain and sno\V consists of: lead(Pb). copper (Cu). Zinc (Zn). Chromium (Cr). anions such as: 504-- and N03- . acidity (pH). Electro coductivity (EC). Chloride ion t (1- ) and Calcium Carbonate (CaC03). Annual wet deposition ofN03- is over 10 kglha and 38 kglha for S04--. inside Chitgar Parkland. Acidity were measured as much as 4.3 . The pH amount showed that acidity \vere 25 times higher than the amount for back-ground acidity in natural precipitation. Reduction of pH scale in Chitgar precipitation could be related to man-made pollution originating from fossil fuel consumption. solid \vaste burning and so on. EC was measured up to 230 micro Siemense per cm (lSicm). High amount of EC should be concerned to high amount of minerals and Suspended Particulate \'!aner (S.P.M ) in atmosphere. Measurement of cr showed that Wet Deposition of CI- was 2.3 kg/ha.year for snow and 30 kg/ha.year for rain samples.These high amounts of CI" attributed from solid waste burning containing P.V.C and S.P.iV!. HCI accompanied with H2S04 and HN03 which in turn contribute to weakness and ,,,'etting. of affected trees. Pi::> is accumulated as much as 70g /ha by precipitation. \yhich is accompanied with 1.3 .kg/ha annual Dry Deposition of Pb. Seasonal sampling for NO - showed that, .there \vas significant ditference between cold and warm season in level of % 1 confidence. In cold seasons production ofN03- is not parallel with increased consumption of fossil fuels. It means that photochemical reaction conditions does not occur during wimer and cold season. Simultaneously measurement ofPb in healthy and pale-colored pine trees indicated that concentration of Pb was 2 fold higher for the latter pines. High amount of Pb leads \0 weakness of vegetation cover together with other stress inducing factors suchas : draughts and long dried period.