پیوندهای مفید
اخبار و اعلانات
آمار
| تعداد نشریات | 161 |
| تعداد شماره‌ها | 6,572 |
| تعداد مقالات | 71,027 |
| تعداد مشاهده مقاله | 125,499,129 |
| تعداد دریافت فایل اصل مقاله | 98,761,349 |
ارائه مدل مناسب پراکنش تعداد در طبقات قطری توده های طبیعی و ناهمسال راش شمال ایران ( جنگل های سنگده و شصت کلاته ) | ||
| مجله منابع طبیعی ایران (منتشر نمی شود) | ||
| مقاله 8، دوره 58، شماره 4 - شماره پیاپی 1000091، دی 1384 اصل مقاله (779.95 K) | ||
| نویسندگان | ||
| اصغر فلاح؛ محمود زبیری؛ محمد رضا مروی مهاجر* | ||
| عنوان مقاله [English] | ||
| An Appropriate Model for Distribution of Diameter Classes of Natural Beech Stands in the Sangdeh & Shastkolateh Forests | ||
| چکیده [English] | ||
| This study has been carried out to obtain an appropriate model for the distribution of natural beech population in diameter classes'in two different forest areas of Sangdeh and Shastkolateh in nothern Iran. Two different regions of beech forest were selected according to their varied age as well as varied growing conditions. These were separated from other sections and therefore four sample areas in one hectare selected for an overall sampling.Then, the numbers of points were plotted according to diameter class. Among different variants, diameter at breast height was shown to represent a reasonable distribution of points. Also statistical distribution of Beta, Weibule, Exponential, and Power were investigated in relation to distribution of points, their efficiency being concluded through chi-square. The results indicate that •from among different methods, regression model bears the most suitable estimation for the mentioned regions. Power model for both selected areas and Beta distribution for Shastkolateh are expected to end up with reasonable results. Finally it can be concluded, although selective method is used as an approach ifor the distribution trend in forest stands, but, the above mentioned models can be recommended as more appropriate for the study areas. | ||
|
آمار تعداد مشاهده مقاله: 781 تعداد دریافت فایل اصل مقاله: 644 |
||
سامانه مدیریت نشریات علمی. قدرت گرفته از سیناوب