اثر نوع قرارداد کار بر اجرای عملیات قطع درختان و مقدار افت چوب

نوع مقاله: علمی- پژوهشی

نویسندگان

1 دانشجوی کارشناسی ‌ارشد، گروه جنگل‌داری، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه‌سرا، ایران

2 دانشیار، گروه جنگل‌داری، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه‌سرا، ایران

چکیده

اهداف پژوهش پیش‌رو مقایسه انواع افت چوب مشاهده‌شده به‌صورت شکستگی، جداشدن ورقه‌ای، ترک و ارتفاع بلند کنده و بررسی اجزای قطع شامل ارتفاع و عمق بن‌زنی، دهانه بن‌زنی، ارتفاع و عمق بن‌بری و عرض حاشیه برش بین گروه‌های کاری روزمزد و کارمزد بود. در پارسل‌های شماره 138 و 139 در سری یک ناو اسالم، به‌صورت تصادفی 150 اصله درخت قطع‌شده توسط گروه‌های کاری روزمزد و کارمزد انتخاب شدند. مقایسه میانگین افت کنده بین روش پرداخت دستمزد با آزمون t مستقل و مقایسه میانگین اندازه هر یک از اجزای قطع با قطع متداول با آزمون t جفتی انجام شد. به‌جز عمق بن‌بری در گروه دوم (33/41 سانتی‌متر) و عرض حاشیه برش در گروه اول (6/78 سانتی‌متر) بین مقادیر دیگر قطع در گروه‌های مختلف با مقادیر استاندارد، تفاوت معنی‌داری وجود داشت. میانگین افت کنده برای گروه‌های چهارگانه به‌ترتیب 0/0350، 0/0355، 0/0498 و 0/0438  متر مکعب بود و گروه‌های کاری روزمزد به‌طور معنی‌داری افت کنده کمتری در مقایسه با گروه‌های کاری کارمزد داشتند. میانگین افت به ازای هر درخت قطع‌شده بین چهار گروه کاری به‌ترتیب 0/2915، 0/2286، 0/3775 و 0/4637 متر مکعب بود و مقدار آن در گروه‌های کاری کارمزد به‌طور معنی‌داری بیشتر از گروه‌های کاری روزمزد بود. حجم بیشتری از افت چوب در تمام گروه‌های کاری به‌صورت شکستگی و خرد شدن بود. با توجه به قیمت محصولات مختلف تولیدی از چوب‌آلات مقطوعه، نتایج نشان داد که گروه‌های کاری کارمزد بیشترین مقدار کاهش ارزش پولی را داشتند. 

کلیدواژه‌ها


عنوان مقاله [English]

The effect of labor work contract on felling operation and wood losses

نویسندگان [English]

  • Moazzameh Ghasempour 1
  • Mehrdad Nikooy 2
  • Ramin Naghdi 2
1 M.Sc. Student, Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran
2 Associate Prof., Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran
چکیده [English]

The objectives of study were to compare different types of wood loss including breakage, split, slab, and high stump and also to investigate cut components such as, height and depth of undercut and back cut, notch, and width of hinge wood between the two groups of workers. Parcels no. 138 and 139 in Asalem Nav series 1 were chosen as the study area. 150 felled trees by workers paid by piece and day work method were selected randomly. The mean stump loss between the two groups was compared by Independent- Sample T- test and the comparison between the size of each components of felling and the standard felling was made by Paired Sample T-test. There was a significant difference between felling values in different groups compared with standard values except the depth of back cut in the second group (33.41 cm) and the width of hinge wood in the first group (6.78 cm). The average high stump loss for the four groups was 0.035, 0.0355, 0.0498, and 0.0438 m3, respectively. The average loss per felled tree among the four groups was 0.2915, 0.2286, 0.3775 and 0.4637 m3, respectively. There was a significant difference between mean value losses of wood in the four groups; the day work paid group had fewer losses compared the piece work paid group. The largest volume of loss in all groups belonged to breakage damage. Regarding the price of different products fabricated from the wood cut, results showed that the greatest decrease in price belonged to the groups paid by piece work contract.

کلیدواژه‌ها [English]

  • Asalem
  • breakage
  • felling labor
  • payment contract method
  • tree stump
  • wood loose
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