The precision of photography method for estimation of canopy cover in shrublands of Yazd province

Canopy cover data are important for range management decisions and there are different methods of estimation. Introducing a method with adequate speed and precision and low cost is important in range management studies and researches. According to development of new technologies in photography soft- wares and hard-wares, it can provide an opportunity to study in a large scale at a short time and low cost. If its accuracy be fine, then it could be used in monitoring projects. This study carried out for study of accuracy and efficacy of vertical photos prepared with digital camera and application of existing soft-wares in estimations of canopy cover percentage of shrublands in Yazd province. Three sites representing Yazd shrublands were selected: 1- Nir rangelands with Artemisia aucheri as dominant species, 2- Shirkooh rangeland with Artemisia sieberi as dominant species and 3- Chahafzal rangeland with Seidlitzia rosmarinus as predominate species. Sampling was carried out in these three sites after determining sample size with drawing method and plot size according to the canopy of dominant species. Photography was performed in suitable height using a camera in the centre of plot and makes sure the photo include the whole area of plot. Simultaneously, canopy cover percent was measured directly with meter tap. Canopy cover percentage also was determined by prepared digital photos after inserting them to computer and using Arc View soft-ware. The percentage of canopy cover by species, in photography and direct methods were compared using SPSS soft-ware and using Paired T-test. There were not significant differences between canopy cover percentages estimated by two methods at %5 level. According to the results Photography with existing soft-ware could be used for determining canopy cover percentage in shrub lands of Yazd province.