تحقیقات جنگل و صنوبر ایران (Mar 2008)
Qualitative investigation of Gall Oak (Quercus infectoria Oliv.) acorns in untouched and pruned forest stands of Baneh (Kurdistan province, N-W Iran)
Abstract
Due to encroachment and intense utilization, natural ecosystems of Zagros lost their normal trend and have converted to fragile and sensitive ecosystems. There are dense human populations that live in these forests which are depended on these forest resources. One of the most important utilizations in northern Zagros is Galazani (pruning) and using of oak limbs as fodder. This kind of use leads to prominent changes in forest structure and its physiognomy in some region (for example Alot in Kurdistan province) which can be a hazard for forest sustainability. Regarding to this problem and having no regeneration from seed, qualitative characteristics of Gall oak acorns, that is one of the most prominent species in these forests, was investigated in three untouched and pruned sites. Totally 60 Gall-oak trees (10 trees per site) and 6000 acorns (100 acorns per tree) were collected. Primary moisture of acorns in untouched sites was a little more than in pruned sites but there was no significant difference between them. The weevil Curculiogladium and Balaninusgladium were the insect species that predated the acorns collected from our sites. There were significant difference (in level of 95%) in the infestation rate among untouched and pruned sites of Blake, however in Ghole-shir and Mir-Yousef sites were no significant differences between insect-infested acorns. The weight of thousand acorns was significantly more in untouched sites; probably because of having more time to storing enough nutrients in their cotyledons. Germination percent and germination index data were analyzed by simple One Way ANOVA, and their averages were compared by Duncan test. There were no significant differences between germination percent of untouched and pruned sites. Comparing means indicate that, Blake site with 96.75 germination percent was placed in group A, Ghole-shir and Mir-Yousef sites were placed in group B with 90.78 and 88.75 germination percent, respectively. Germination index of untouched and pruned sites had no significant differences and in Duncan grouping they placed in one group. The values for germination index in Mir-Yousef, Blake and Ghole-shir sites were 13.18, 12.83 and 12.36, respectively.