Persian oak (Quercus brantii Lindl.) is a valuable native species in Iranian forests with very limited availability of data on its wood properties. The objective of the current study was to determine the influence of altitude and slope on physical properties and fiber dimensions of Persian oak wood. In addition, the relationship among wood properties, site conditions (temperature and rainfall) and growth traits of trees (tree height, DBH, basal area, age, crown diameter, crown basal area, volume and annual diameter increment) were studied by principal component analysis (PCA). Three altitude levels (1730, 1980 and 2250 m) and three slope classes (<30%, 30–45% and >45%) were considered in the current study. It was determined that trees growing in the intermediate altitude (1980 m) showed the highest oven-dry density values, and those in the lowest altitude (1730 m) revealed the lowest ones. The results also indicate significant statistical differences between altitude levels and slope classes on the fiber length, fiber diameter and volumetric swelling at the 99% confidence interval while no significant differences were found between average values of oven-dry density among different altitudes and slopes. PCA analysis indicated that altitude and temperature are the most important factors affecting the wood properties. Knowledge of the relationship between wood properties and environmental factors are essential in terms of both forestry management and wood applications.

This study investigated the influence of site conditions on the physical and morphological properties of hawthorn (Crataegus azarolus L.) wood grown in Zagros forests of Iran. Hawthorn is a valuable woody species in Iran’s Zagros forests with data deficiency in its wood properties. To our best knowledge, there is no study on the properties of hawthorn wood. Twenty-seven mature trees were randomly chosen and sampled at three altitude levels (1 800–2 000, 2 000–2 200, and 2 200–2 400 m) in the Bazoft region of Chaharmahal Va Bakhtiari, Iran. Dry wood density, volumetric shrinkage, fibre length, fibre diameter, cell wall thickness were then determined. Multivariate analysis of variance (MANOVA) was conducted to evaluate significant differences between the mean values of studied wood properties at different altitude levels and slope classes. Moreover, the relationships between the above-mentioned properties and some site conditions (temperature, precipitation, altitude, and slope) as well as growth parameters of trees (tree height, DBH, age, crown dimensions, volume, etc.) were studied by principal component analysis (PCA). The results indicated that trees growing at the second altitude level had the highest oven-dry density values, and those at the third altitude level had the lowest ones. Results also indicated a significant effect of altitude levels on fibre length, fibre diameter, and cell wall thickness. In contrast, a significant difference was found between the mean values of fibre diameter at different slope classes. PCA indicated that altitude, precipitation, and temperature are the most important environmental site variables affecting the wood characteristics.

high level of agreement with self-thinning rule of − 3/2. Values for the stand density index for coppiced oak woodlands were between more than 1000 for the least disturbed (Co) and less than 400 for the most disturbed woodlands (CoCG). The structure and growth rate of the coppiced oak woodlands were irreversibly disrupted by understory tillage plus grazing and in less extent by grazing alone. It was concluded that ending undergrowth cultivation in semi-arid oak coppices should be addressed as a priority by adopting minimum regulations.

Despite the importance of Hyrcanian forests for biodiversity conservation, a few studies with biomass destruction has been done to predict biomass and carbon pools from this forest and there is a lack of knowledge in our country. Biomass and leaf area index (LAI) are important variables in many ecological and environmental applications and forest management. In this paper, allometric biomass and leaf area equations were developed for three common Hyrcanian tree species, Oriental Beech (Fagus orientalis Lipsky), Hornbeam (Carpinus Betulus Lipsky) and Chestnutleaved Oak (Quercus castaneifolia C. A. Mey). To evaluate and estimate the leaf biomass and leaf area index of Oriental Beech, Horbeam and Chestnut-leaved Oak, 21, 27 and 17 individuals were selected and felled down, respectively. Tree characteristics such as diameter at breast height, total height, crown length and perpendicular diameters were measured. Destructive sampling was applied for determination of leaf biomass and LAI. Allometric equations were calculated for estimation of leaf biomass and LAI using simple linear regression and nonlinear regression analysis. The equations were compared based on several modelling parameters. Model comparison and selection were based on R 2 , Akaike's information criterion (AIC), prediction error sums of squares, model standard error estimate (SEE), ΔAIC, and a correction factor. Based on the results, the mean values of leaf area, leaf biomass and LAI for Oriental Beech were 53.05 cm 2 , 0.176 gr, 2.16, for Hornbeam were 27.2 cm 2 , 0.128 gr, 1.13 and for Chestnut-leaved Oak were 62.419 cm 2 , 0.401 gr, 2.26, respectively. The highest significant correlation for Oriental Beech was found between LAI and total height (R 2 adj = 0. 931), the highest significant correlation for Hornbeam was found between LAI and Dbh (R 2 adj = 0. 956) and the highest significance for Chestnut-leaved Oak was found between LAI and SqrtDbh (R 2 adj = 0. 956). Also, the best equations were obtained by means of an