جستجوی مقالات مرتبط با کلیدواژه « volum table » در نشریات گروه « جنگلداری »

Poplar cultivation are the most important sources of wood production in the country and the lands along Zanjan-Rood river are one the best sites for poplar plantation. The plantation consists mostly of two species: P. nigra cv.”pubescens” and P. alba cv.”shirazi”. After section some sample from 98 pople plantation sites located between kooshkan and nickpay villages of west Zanjan city, the tree samples were fell down, cut, logged and measured. The data were analyzed, using the SPSS software. As a result, the most appropriate aquations were calculated and defined for the tree volume tables . Overall,three volume tables were developed separately for each species from the aquations. In addition, weight and volume of some popliar loges were calculated and their volum coefficient were estimated. The results showed that: 1-In diameters and heights equal to 50 cm and 25 m respectively, the volume of P. alba and P. nigra will be 2.5 and 2 cubic meters, respectively. 2-Based on all the growth variables (diameter,height,volum and qualitative characteristics ),P. alba cultivars were the best. 3- Because P. alba cultivars have woods with better quality than P. nigra cultivars, their economical values are greater than P. nigra culivars as well.