عامل‌های مؤثر در شکل‌گیری ساختار جنگلی حاشیه رودخانه ارس (مطالعه موردی: استان اردبیل)

نوع مقاله: علمی- پژوهشی

نویسندگان

1 هیأت علمی دانشگاه ملایر

2 پژوهشگر موسسه تحقیقات جنگلها و مراتع کشور

چکیده

بهمنظور بررسی عاملهای مؤثر در شکل‌گیری ساختار پوشش جنگلی حاشیه رودخانه ارس، منطقه موردمطالعه براساس مشخصههای پوشش گیاهی (طبیعی و دستکاشت)، اندازه تخریب حاشیه رودخانه و عوارض طبیعی به پنج واحد تقسیم شد. در هر واحد، شرایط اکولوژیکی، مسائل اقتصادی- اجتماعی و خصوصیات جنگل‌شناسی مانند تراکم، قطر متوسط، ارتفاع متوسط، شکل پرورشی، تاجپوشش، وضعیت و کیفیت درختان بررسی و اندازه‌گیری شدند. بررسی مشخصههای جنگل‌شناسی از طریق 20 قطعهنمونه مربعیشکل به ابعاد 10×10 متر و بهروش منظم- تصادفی انجام گرفت. با توجه به یافته‌های تحقیق مشخص شد که در واحدهای موردمطالعه اختلاف معنیداری بین تراکم گونه‌ها در سطح اطمینان 99 درصد وجود دارد، درحالی‌که قطر و ارتفاع متوسط گونه‌ها هیچگونه اختلاف معنی‌داری را نشان ندادند. مطالعه وضعیت اقتصادی- اجتماعی در هریک از واحدهای مورد مطالعه نشان داد که بین دام‌های موجود در منطقه طرح با تراکم گونه‌ها ارتباط معنیدار منفی در سطح اطمینان 99 درصد وجود دارد، درحالیکه بین جمعیت موجود و تراکم گونه‌ها هیچگونه ارتباط معنیداری وجود ندارد. دیگر نتایج این بررسی نشان داد که بین تراکم گونه‌های درختی موجود با بافت خاک ارتباط معنیداری در سطح اطمینان 95 درصد وجود دارد.

کلیدواژه‌ها


عنوان مقاله [English]

Effective factors in formation of forest structure in Aras riparian zone (Case study: Ardebil Province)

نویسندگان [English]

  • Farhad Ghasemi Aghbash 1
  • Ali Mohebbi 2
1 Assistant Professor, Department of Forestry, Faculty of Natural Resources and Environment, University of Malayer, Malayer, Iran
2 Research Expert, Research Institute of Forests and Rangelands, Tehran, Iran.
چکیده [English]

A study was conducted to investigate the effective factors in the formation of the forest structure across the Aras Riparian Zone in northwestern Iran. To this aim, the study area was divided into 5 units based on the vegetation status (natural, artificial), destruction rate of riparian zone and topography. The silvicultural (e.g. density, average diameter, average height, growth form, canopy cover and quality of trees), ecological and socioeconomic ecological, socioeconomic parameters were studied in each unit.The silvicultural parameterswere surveyedwithin a number of 20 sample plots each encompassing 10×10 m which were selected by randomized systematic design. The results showed that species density was the only factor showing a significant difference (p<0.01) amongst the units, whereas the average diameter and the average height did not were not significantly different. As a socioeconomic factor, livestock showed to bear a negative significant correlation with species density (p<0.01), whereas the population proved not to be significantly associated with species density. Further results showed that a difference in soil texture is significantly correlated (p<0.05) with the density of tree species. 

کلیدواژه‌ها [English]

  • Silvicultural parameters
  • riparian zone
  • Forest structure
  • Aras river basin
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