نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانش آموخته کارشناسی ارشد دانشگاه سمنان
2 استادیار موسسه تحقیقات جنگل ها و مراتع کشور؛ گروه جنگلداری مناطق خشک دانشکده کویرشناسی دانشگاه سمنان (92-98)
3 دانشیار دانشکده منابع طبیعی دانشگاه تهران
4 استادیار گروه جنگلداری مناطق خشک دانشکده کویرشناسی دانشگاه سمنان
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Iran’s Hyrcanian forests are part of the temperate forests and have survived since Tertiary. These forests have experienced severely damages in recent decades because of socio-economic issues such as overgrazing. This study aimed to investigate the Nurse-protégé interaction and the impact of understory shrub species on the regeneration of the Hyrcanian main tree species in Kheyrood Forests. Sampling was carried out using the random-systematic method. Regeneration and their features under and outside of the canopy of shrub species, as well as some environmental variables were recorded in strip plots. According to the results, the canopy cover percentage of 25-50% provides the best regeneration protection efficiency for the six nurse shrub species. Overall, regeneration density was found to be higher outside of the canopy area of the shrub species than beneath their canopy area; however, regeneration under the shrub species resulted in higher mean height and age. Moreover, the mean cover and the depth of the litter under the shrub canopy were significantly higher than outside of the canopy area. Although the shrub species allow more durable and complete development of seedlings by providing protection against grazing, suitable conditions for seed germination and seedling growth may not be provided because of high litter depth and Insufficient sunlight due to the massive canopy of trees as well as nurse shrubs’ dense foliage (especially, evergreen understory species).
کلیدواژه‌ها [English]
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