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The importance of vegetation as a dynamic factor affecting the biological conditions requires that a detailed qualitative and quantitative information about its changes be prepared in short intervals. In this study, in order to monitor and predict vegetation density in Venet watershed in Ilam province the Normalized difference vegetation index (NDVI) and Landsat images from 1988 and 2007 was used and vegetation density maps in three classes without canopy cover, thinned and dense canopy covers were prepared. Comparing the extent of vegetation density classes indicated that the extent of bare soil areas have increased as 1158/837 hectares while the extent of thinned and dense canopy covers 360/8277 and 797/9544 hectares respectively has been reduced. Assessing changes in vegetation density showed that from the classes with thinned and dense canopy covers as 1233/4828 and 210/4539 ha respectively have become no vegetation cover class. Also as 246 /2742 and 38 /8255 hectares of the bare soil areas have been converted to thinned and dense canopy cover classes respectively. Using Markov models and automated cells to predict changes in vegetation density showed that the highest and lowest probability of transition to no vegetation cover lands has been seen respectively in thinned (0.5059) and dense canopy cover (0.1023) lands. Finally, assuming a continuation of current trends, watershed vegetation density map of the target for 2020 was forecast. This map shows in the near future the land without vegetation cover will devote itself about 87 percent of this region.

Background and objectives: Site demands and characteristics of different plant species is necessary for forest protection and restoration. Therefore, soil properties determination is one of the most important steps in plant species site demands determination. This research was conducted to understand sire demands of Lonicera nummulariifolia in Chaharmahal and Bakhtiari Province. Besides, to determine the most important soil factors affecting on L. nummulariifolia distribution.  
Materials and methods: Four sites including Gazestan (1792 m above sea level), Samsami (2210 m a.s.l.), Kohrang (2215 m a.s.l.), and Ardal (1531 m a.s.l.) were selected in Chaharmahal and Bakhtiari province. Soil samples were taken from the depth of 0-30 cm. soil physicochemical properties including soil nitrogen, available potassium, organic carbon, pH, and electrical conductivity, were determined. Besides, quantitative characteristic of trees (tree diameter, height, and crown diameter) were measured. Soil properties were evaluated using one-way ANOVA. Furthermore, principal component analysis was used to determine the most important soil variables affecting L. nummulariifolia distribution.
Results: Results of this study indicated that the tallest and shortest trees with the average of 2.26 and 1.57 belonged to the Kograng and Gazestan, respectively. Also, trees origin in the Samsami site was coppice while in the other three sites they were high stands. Soil physicochemical properties indicated that soil electrical conductivity, nitrogen and organic matter had no significant differences between studied sites. Furthermore, soil pH was almost neutral in studied sites and showed no significant differences. While, Kohrang and Gazestan had the highest significant value of potassium. The least value of potassium was belonged to the Samsami. While, the most and least values of silt belonged to the Gazestan and Kohrang, respectively. Gazestan had the least value of soil sand percent compared to the other studied sites. Conical correspondence analysis indicted that the most important factors affecting L. nummulariifolia distribution are soil organic matter, nitrogen, potassium, electrical conductivity, clay, aspects, and slope respectively. 
Conclusion: L. nummulariifolia distribution demands for sites with the higher soil nutrient and organic carbon. Also, it’s prefer neutral soil pH. In the other world soil physiochemical properties play and important role in L. nummulariifolia distribution and information about site requirements of this species could help to identify proper sites for reforestation to enrichments of Zagros forest.