نوع مقاله : مقاله پژوهشی
نویسندگان
1 عضو هیات علمی گروه علوم جنگل دانشگاه علوم کشاورزی و منابع طبیعی گرگان
2 دانشیار پژوهشی، بخش تحقیقات جنگل، موسسه تحقیقات سازمان جنگل‌ها، مراتع و آبخیزداری، تهران، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Deadwood have multiple enormous functions in forest ecosystem while the most important, is their role as biotope (a habitat for life and a source of nutrients and energy).The present research evaluates abundance and diversity of macrofauna found in fallen hornbeam deadwood in different decay rates and in different altitude from sea level. For this, purpose, 108 fallen hornbeam deadwood in three altitudes from sea level of 200-450, 450-700 and 700-950m with three replications for fallen deadwood in different decay rates and three replicates were sampled from three diameter classes less than 40, 40-70 and more than 70cm. Macrofauna were separated from deadwood by hand sorting then identified, by systematic key there after weighed in 0.001 gr precision. Macrofauna biodiversity was calculated through diversity, evenness and richness indices (Shannon, Simpson and Margalef respectively). The results showed that there was a significant difference between the mean of richness and diversity of biomass and the frequency of macrofauna in fallen hornbeam deadwood in different decay rates, so that with increasing decay rates, richness and variety of macrofaune increased. The highest number of macrofaune was observed in the deadwood decay class 4 and in diameters of 40-70 and 70-100cm. The highest frequency of macrofaune orders is in the lowest altitudinal class (200-450m above sea level) and the lowest frequency is in the highest altitudinal class (700-950m) while there was no significant difference between altitudinal class 1 and 2. A significant decreasing relationship was observed between deadwood length and frequency of macrofaune orders. In this study, with increasing altitude, biomass uniformity, increase and richness of biomass decreased, so it can be said that the effect of each other on biomass diversity of macrophona order was neutralized and as a result, no significant difference was observed for the biomass diversity of macrophona order at different altitudes.
کلیدواژه‌ها [English]
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