نتایج جستجو برای: height of trees

تعداد نتایج: 21175163  

2015
Zhugeng Duan Dan Zhao Yuan Zeng Yujin Zhao Bingfang Wu Jianjun Zhu

Topography affects forest canopy height retrieval based on airborne Light Detection and Ranging (LiDAR) data a lot. This paper proposes a method for correcting deviations caused by topography based on individual tree crown segmentation. The point cloud of an individual tree was extracted according to crown boundaries of isolated individual trees from digital orthophoto maps (DOMs). Normalized c...

Journal: :محیط زیست طبیعی 0
وحید علی جانی دانشجوی کارشناسی ارشد گروه جنگلداری و اقتصاد جنگل دانشکده منابع طبیعی دانشگاه تهران، ایران جهانگیر فقهی دانشیار گروه جنگلداری و اقتصاد جنگل دانشکده منابع طبیعی دانشگاه تهران، ایران محمود زبیری استاد گروه جنگلداری و اقتصاد جنگل دانشکده منابع طبیعی دانشگاه تهران، ایران محمدرضا مروی مهاجر استاد گروه جنگلداری و اقتصاد جنگل دانشکده منابع طبیعی دانشگاه تهران، ایران

quantifying spatial structure is one of the most important components, describing natural ecosystems and their biodiversity. in this study, a set of indices and functions related to spatial structure using 102 established plots with an area of 1000 m2 were presented. to achieve spatial structure of carpinus-fagus type, a set of indices (clark & evans, uniform angle, shannon-wiener, mingling and...

Journal: :پژوهش های علوم و فناوری چوب و جنگل 0

this research was conducted to investigate the effect of planting space on fiber morphology of acer velutinum. in this work, from each treatment including planting space of 1×1, 1.5×1.5 and 2×2 meters, four trees were cut from shastkalateh plantation of gorgon university and factors such as length and annual diametrical growth of trees as well as length, diameter and wall thickness of fibers we...

Journal: :Global change biology 2017
Tommaso Jucker John Caspersen Jérôme Chave Cécile Antin Nicolas Barbier Frans Bongers Michele Dalponte Karin Y van Ewijk David I Forrester Matthias Haeni Steven I Higgins Robert J Holdaway Yoshiko Iida Craig Lorimer Peter L Marshall Stéphane Momo Glenn R Moncrieff Pierre Ploton Lourens Poorter Kassim Abd Rahman Michael Schlund Bonaventure Sonké Frank J Sterck Anna T Trugman Vladimir A Usoltsev Mark C Vanderwel Peter Waldner Beatrice M M Wedeux Christian Wirth Hannsjörg Wöll Murray Woods Wenhua Xiang Niklaus E Zimmermann David A Coomes

Remote sensing is revolutionizing the way we study forests, and recent technological advances mean we are now able - for the first time - to identify and measure the crown dimensions of individual trees from airborne imagery. Yet to make full use of these data for quantifying forest carbon stocks and dynamics, a new generation of allometric tools which have tree height and crown size at their c...

Journal: :Annals of botany 2011
Rie Miyata Takuya Kubo Eri Nabeshima Takashi S Kohyama

BACKGROUND AND AIMS Morphology of crown shoots changes with tree height. The height of forest trees is usually correlated with the light environment and this makes it difficult to separate the effects of tree size and of light conditions on the morphological plasticity of crown shoots. This paper addresses the tree-height dependence of shoot traits under full-light conditions where a tree crown...

ژورنال: مهندسی دریا 2013

Wind waves are one of the important, fundamental and interesting subjects in port and coastal engineering. Thus, within years, different methods such as experimental methods, numerical modeling and soft computing methods have been employed to estimate the wave parameters. In this study, waves height in Anzali port is predicted using soft computing models such as multivariate adaptive regressi...

Journal: :journal of agricultural science and technology 2014
e. yildiz m. kaplankiran t. hakan demirkeser c. toplu m. uysal-kamiloglu

the effects of rootstocks such as 'sour orange' (citrus aurantium l. var. ‘yerli’), 'carrizo' and 'troyer citranges' (citrus sinensis osb. x poncirus trifoliata raf), 'smooth flat seville sour orange' (citrus spp. hybrid of uncertain origin), 'brazilian sour orange' (citrus aurantiam l. var. ‘brasilian’), 'volkameriana' (citrus volkameriana tan. and pasq.) and 'calamondin' (possibly citrus reti...

Journal: :Tree physiology 2012
Julia A Sohn Martin Kohler Arthur Gessler Jürgen Bauhus

Radial stem growth and the isotopic composition of growth rings are commonly used to quantify the effects of droughts on trees. However, often these parameters are quantified only at one stem height, e.g., 1.3 m, and it is not known how representative this is for the whole stem. This study investigated radial growth at four stem heights (1.3, 5.5, 9.8 and 14 m) of 21, and wood Δ(13)C and δ(18)O...

Journal: :Ecological applications : a publication of the Ecological Society of America 2014
Rosa C Goodman Oliver L Phillips Timothy R Baker

Tropical forests play a vital role in the global carbon cycle, but the amount of carbon they contain and its spatial distribution remain uncertain. Recent studies suggest that once tree height is accounted for in biomass calculations, in addition to diameter and wood density, carbon stock estimates are reduced in many areas. However, it is possible that larger crown sizes might offset the reduc...

2017
Ivan Sačkov Maroš Sedliak Ladislav Kulla Tomáš Bucha

This study is concerned with the assessment of application possibilities for remote sensing data within a forest inventory in close-to-nature forests. A combination of discrete airborne laser scanning data and multispectral aerial images separately evaluated main tree and forest stand characteristics (i.e., the number of trees, mean height and diameter, tree species, tree height, tree diameter,...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید