pistachio psylla, agonoscena pistaciae burckhardt & lauterer, is a key pest of pistachio trees in the pistachio-producing regions throughout iran. the investigation of biology of pests under the field condition in each region is the first step that must be taken in developing an integrated pest management program. the seasonal fluctuations of eggs, nymphs and adults of pistachio psylla were inv...

As trees grow taller, decreased xylem path conductance imposes a major constraint on plant water and carbon balance, and is thus a key factor underlying forest productivity decline with age. The responses of stomatal conductance, leaf area: sapwood area ratio ( A L : A S ) and soil–leaf water potential gradient ( DY S–L ) to height growth were investigated in maritime pine trees. Extensive meas...

We study the diameter of Lévy trees that are random compact metric spaces obtained as the scaling limits of Galton-Watson trees. Lévy trees have been introduced by Le Gall and Le Jan (1998) and they generalise Aldous’ Continuum Random Tree (1991) that corresponds to the Brownian case. We first characterize the law of the diameter of Lévy trees and we prove that it is realized by a unique pair o...

A procedure for both vertical canopy structure analysis and 3D single tree modelling based on Lidar point cloud is presented in this paper. The whole area of research is segmented into small study cells by a raster net. For each cell, a normalized point cloud whose point heights represent the absolute heights of the ground objects is generated from the original Lidar raw point cloud. The main t...

Effective separation of buildings from trees is a major challenge in image-based automatic building detection. This paper presents a three-step method for effective separation of buildings from trees using aerial imagery and LIDAR data. Firstly, it uses cues such as height to remove objects of low height such as bushes, and width to exclude trees with small horizontal coverage. The height thres...

Despite renewed interest in the nature of limitations on maximum tree height, the mechanisms governing ultimate and species-specific height limits are not yet understood, but they likely involve water transport dynamics. Tall trees experience increased risk of xylem embolism from air-seeding because tension in their water column increases with height because of path-length resistance and gravit...