استفاده از عكس هاي هوايي در برآورد نرخ تخريب جنگلهاي چهارزبر استان كرمانشاه

Estimation of deforestation rate in Chaharzebar forests in Kermanshah Province using aerial photographs.

In order to estimate deforestation rate consider in Chaharzebar forests, with 10035 ha area in 34 km South west of Kermanshah, we studied aerial photographs of years 1955 and 1990 with the scale 1 : 50000. Results of two methods are shown as follow: 1- Sampling through dotted lattice: by average within a 35 years period of time, the forest areas has declined by 6% and the relative surface of 602 ha shows 0.16% decline (17.2 ha per year) 2- Drawing and separating the forest areas by photographs: the decline forest area in this 35 year period is 641.6 ha which is 18.33 ha annually by average. On the other hand the non- forest areas has been increased. Deforestation rate in this region within 35 years is totally 5.95% and 17% annually.