Comparing the forest quantitative and qualitative characteristics following a period of forestry plan implementation (Case study: Watershed 65, Jojadeh zone of Farim Company, Mazandaran province)

Abstract

To assess the changes in qualitative and quantitative attributes at the end of a period of forestry plan implementation, a portion of the Jojadeh zone with an area of 1270 ha was selected. Data were collected from 265 permanent plots in a systematic random design (1000 m2 plots and150 × 200 m grid size) in 2004 and 2014 to facilitate a comparison. In each plot diameter, species, quality grade, height of control tress and quality of regeneration (in 100 m2 microplots) weree measured. During the ten-year period, approximately 14000 silve of growing stock was marked within a single tree selection cutting system. The results showed following figures for 2004: the average number of trees per ha=173, volume per ha=318.36 silve, basal area per ha= 25.87 m2, diameter of basal area= 43.93 cm and Lorey’s mean height= 25.31 m. The values in 2014 were 175, 360.24 silve, 28.31 m2, 43.39 cm and 26.40 m, respectively. Apart from number of trees per ha, significant differences were observed between the two measurement times for the other attributes. Furthermore, the species specific regeneration frequency was affected by a significant reduction in seedling and saplings in 2014. However, tree percentages increased in 1st and 3rd quality grade classes, whereas it decreased 2nd class andd remained unchanged in 4th class. All in all, the results showed that the average values of quantitative and partlyy qualitative characteristics were not far from favorable conditions during the period of forestry plan, which indicated the conducted silvicultural practices served the defined goals of the close to nature forestry method.

Keywords

• Average diameter of basal area
• Lorey’s height
• qualitative and quantitative characteristics