development of an allometric model to estimate above-ground biomass of forests using mlpnn algorithm, case study: hyrcanian forests of iran

نویسندگان
چکیده

this research develops an allometric model for estimation of biomass based on the height and dbh of trees in the hyrcanian forests of iran. an accurate allometric model reduces the uncertainty of allometric equation in biomass estimation using radar images. in this study, 317 trees were selected randomly from the 4 different dominant tree species for the development of an allometric model covering the wide range of dbh and height classes. the selected trees were measured by fieldwork in different parts and then volumes of these parts were calculated separately. total volume of tree is obtained by the summation of these volumes. twelve commonly used allometric models, three generalized models and a proposed model were tested and the most suitable model was selected based on some of the commonly measured statistical parameters including coefficient of determination (r2), root-mean-square error (rmse) and mean error (me). we showed that the biomass estimation accuracy was improved in a multilayer perceptron neural network (mlpnn) when density of wood, dbh and height were used in combination compared to estimating the biomass by current allometric models. the rmse value was decreased when the proposed method was used (rmse =0.163 mg and r2=0.986) in comparison with chave model, as the best current method (rmse =0.404 mg and r2=0.957) in this paper.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Development of an allometric model to estimate above-ground biomass of forests using MLPNN algorithm, case study: Hyrcanian forests of Iran

This research develops an allometric model for estimation of biomass based on the height and DBH of trees in the Hyrcanian forests of Iran. An accurate allometric model reduces the uncertainty of allometric equation in biomass estimation using radar images. In this study, 317 trees were selected randomly from the 4 different dominant tree species for the development of an allometric model cover...

متن کامل

Modeling the Degradation of Hyrcanian Forests Using Logestic Regression Method (Case Study: Shenrood Forests, Guilan)

Having accurate quantitative and qualitative information about the state of forest stands, is necessary for any basic management and planning, to reduce the effects of forest degradation. The current study aimed to model the destruction of Hyrcanian forests under the effects of density and volume (per hectare) variables, using logistic regression. In total, 252 plots of 1000 m2 area were measur...

متن کامل

Comparison of allometric equations to estimate the above-ground biomass of Populusalba species (Case study; poplar plantations in Chaharmahal and Bakhtiari province, Iran)

Carbon sequestration into plants biomass, especially in fast growing trees is an easier and economically way for dropping off CO2 from atmosphere. This study was carried out in order to investigate above-ground biomass of white poplar (populous alba, L.) plantations that was planted in fourdifferent plant spacing (0.5 × 0.5, 1×1, 2×2 and 4×4 m.) in Chaharmahal and Bakhtiari province in west of ...

متن کامل

the innovation of a statistical model to estimate dependable rainfall (dr) and develop it for determination and classification of drought and wet years of iran

آب حاصل از بارش منبع تأمین نیازهای بی شمار جانداران به ویژه انسان است و هرگونه کاهش در کم و کیف آن مستقیماً حیات موجودات زنده را تحت تأثیر منفی قرار می دهد. نوسان سال به سال بارش از ویژگی های اساسی و بسیار مهم بارش های سالانه ایران محسوب می شود که آثار زیان بار آن در تمام عرصه های اقتصادی، اجتماعی و حتی سیاسی- امنیتی به نحوی منعکس می شود. چون میزان آب ناشی از بارش یکی از مولفه های اصلی برنامه ...

15 صفحه اول

an investigation about the relationship between insurance lines and economic growth; the case study of iran

مطالعات قبلی بازار بیمه را به صورت کلی در نظر می گرفتند اما در این مطالعه صنعت بیمه به عنوان متغیر مستفل به بیمه های زندگی و غیر زندگی شکسته شده و هم چنین بیمه های زندگی به رشته های مختلف بیمه ای که در بازار بیمه ایران سهم قابل توجهی دارند تقسیم میشود. با استفاده از روشهای اقتصاد سنجی داده های برای دوره های 48-89 از مراکز ملی داده جمع آوری شد سپس با تخمین مدل خود بازگشتی برداری همراه با تعدادی ...

15 صفحه اول

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید


عنوان ژورنال:
caspian journal of enviromental sciences

جلد ۱۴، شماره ۲، صفحات ۱۲۵-۱۳۷

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023