نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه جنگلداری و اقتصاد جنگل، دانشکده منابع طبیعی، دانشگاه تهران، کرج، ایران
2 استاد سنجش از دور دانشکده منابع طبیعی کرج
3 گروه جنگلداری و اقتصاد جنگل، دانشکده منابع طبیعی، دانشگاه تهران
4 گروه علوم و صنایع چوب و کاغذ، دانشکده منابع طبیعی دانشگاه تهران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Altitude, as a key environmental factor, significantly affects tree growth and their functional attributes. This study aims to investigate the changes in diameter growth of beech trees across different altitudinal ranges over a 60-year time series from 1964 to 2024 in the Kheyrud educational and research Forest. To do so, in the forest’s beech-dominated areas, 30 field sample plots with a size of 30×30 meters, with a minimum distance of 250 meters between sample plots, were established across three altitudinal ranges (i.e. below 1,000 m, 1,000–1,400 m, and above 1,400 m). In each plot, five dominant beech trees i.e. the largest tree in term of diameter were randomly selected. In addition to measuring the diameter at breast height (DBH), two increment cores were extracted from each beech tree using an increment borer. After processing the samples and analyzing the data, the results indicated that altitude significantly influences diameter growth, with growth patterns varying across different altitudinal ranges due to environmental and altitudinal factors. The highest annual diameter growth and DBH were observed in the 1,000–1,400 m altitudinal range. In contrast, annual diameter growth was lower at altitudes below 1,000 m compared to mid-altitudes, and a significant reduction in tree growth was observed at altitudes above 1,400 m. Overall, altitude had a negative and decreasing effect on diameter growth, though the pattern and intensity of this effect varied across different altitudinal ranges.
کلیدواژهها [English]
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