نوع مقاله : علمی- پژوهشی
نویسندگان
1 کارشناس گروه تحقیقات صنوبر و درختان سریع‌الرشد، مؤسسه تحقیقات جنگلها و مراتع کشور، تهران، ایران
2 عضو هیئت علمی، گروه جنگلداری و اقتصاد جنگل، دانشکده منابع طبیعی دانشگاه تهران، کرج، ایران
3 عضو هیئت علمی، گروه تحقیقات صنوبر و درختان سریع‌الرشد، مؤسسه تحقیقات جنگلها و مراتع کشور، تهران، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
The cultivation of poplars supply some of countrys demands of wood. Thus, they have an important role to reduce the pressure on forests. The poplar plantation along the Zanjan-Rood river blanks are in valuable. This project was prepared and executed to get information about the structure, variety and growth rate of thepoplar plantations. At first, after explorationof the area, the map of the poplar cultivation in the area was prepared. There are 98 discrete poplar plantation between the village of Kooshkan and Nickpay. Then,on the basis of a statistical plan, 56 plote 300M2 in area were picked throught the area by the “PPS” method. Various data were collected form these. After analysis and processing of the information variable were calculate regression charts provided, and these result were concluded:
- 90% of poplars plantation consist of the two species of P.nigra var “ pubescens” (60%) and P.alba cv “shirazi “ (30%)
- The average volume of these plantation are 270 m3 and about 1100 tree per hectare with a diameter grater than 8 centimeter. The shortage of young trees in the area is very abvious, and the future of the cultivation of poplar the area is danger.
- The trees in the P.alba plantation have a better condition than these in the P. nigra plantation regarding features like, diameter, height, cylindrical form, elongation of trunk, few number of branche excrescence of the trunk, form and thickness of the bark,….
- The trees of the P. alba have 2/5 m3 of volume with the diameter of 50 cm and height of 25m, while trees of the P.nigra with these dimensions are just 1/6 m3 in volume.
Totally, the area is capable of being converted to a plantation of poplars center. It is necessary to in troduce the method of cultivation, and agriculture, by through survey and coherent planning and management. It is also need to give the urgent supports of poplar farmers in long time plans.
کلیدواژه‌ها [English]
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