نوع مقاله : علمی- پژوهشی
نویسندگان
1 عضو هیأت علمی، بخش تحقیقات جنگل، مؤسسه تحقیقات جنگلها و مراتع کشور، تهران،ایران
2 ایستگاه تحقیقات نوشهر، مرکز تحقیقات کشاورزی و منابع طبیعی مازندران،نوشهر، ایران
3 عضو هیأت علمی، گروه جنگلداری و اقتصاد جنگل، دانشکده منابع طبیعی دانشگاه تهران، کرج،ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
The research project of determining Beech seeding cycle was conducted at Kelardasht region of Caspian Forests.
Thirty dominant Beech trees were selected for quantity and quality measurement. After soil and ground cover sampling and tree measurments, the trees were cut down and a disc sample was taken from each tree stump. The discs were analyzed at Division of Wood Science Labs of Research Institute of Forests and Rangelands to study the annual rings. The results showed that:
1- Fagus orientalis has two seeding methods, heavy and light.
2- The minimum age of seeding is about 30 years when is Often associated with light seeding.
3- The heavy seeding begins at age of 60 years.
4- At a same site, different seeding cycles were observed during the living period.
5- The light and heavy seeding continues every 1-5 and 3-18 years, respectively.
6- It seems that natural regeneration depends on light seeding cycles beacause of their frequent occurance.
7- Forest management projects should be based on light seeding cycles rather than heavy seeding cycles. As a result, the harvesting period should be increased from 5 years to 10 or 15 years.
8- There was a relationship between annual ring growth rate and seeding methods as follows:
a. If decrease rate of annual ring growth is less than 0.74 mm, there will not be seeding cycle.
b. If decrease rate of annual ring growth is between 0.74 mm and 15 mm. then there will be light seeding cycle.
c. If decrease rate of annual ring growth is more than 15 mm, there will be heavy seeding cycle.
کلیدواژه‌ها [English]
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