Assessment of elevation and geographical aspect variability on leaf characteristics of ‎trees in the North Zagros forests

The aim of present study is investigating the effect of physiographic factors on leaf area index (LAI), leaf mass per area (LMA) and canopy water content (CWC). 125 square plots with dimensions of 30 meters by 30 meters in cluster method model were sampled. Plot elevation was determined by using digital elevation model (DEM) map. Also 9 aspects were determined by using a compass device. Photographing the canopy and collecting leaves from the canopy were done to estimate the indices. The results showed that the elevation has a significant effect on all indices. The aspect has a significant effect on LAI and LMI indices. LAI and CWC indices decrease from low to high elevations and increase on the highest elevation. The LMA attribute also increases from low to high elevations and decreases in the highest elevation class again. The high LAI value observed in the north and northeast aspect and the lowest LAI observed in the south and southwest aspects. The CWC is higher in northern aspects and it is lower in the southern aspect. LMA is lower in the northern and northeastern aspects while it was higher in the western and south western aspects. Knowing the conditions of vegetation indicators status in different aspects and elevations, provides the possibility of prioritizing support and maintenance measures in different topographical conditions of the region.