the mean fiber length of three beech trees (fagus orientalis l.) at the lower and higher points (1% and 75% tree height) of the stem at an intermediate altitude (500-1000m) in the caspian forests in sari region were 1.36 and 1.22mm respectively, close to the values in three trees at high altitude (1000-1500m), that were found to be 1.39 and 1.36 mm. the mean fiber lengths of the whole stem, usi...

The study of plant under environmental conditions leads to an appreciation of their physical and chemical requirements for growth and reproduction. It contributes to increase the knowledge of where the plants grow. This study was conducted to determine the main autecological characteristics of Salvia hydrangea L. which is an endemic plant distributed in Mazanadarn province, Iran. The habitats o...

The present work has explored for the first time acclimation of upper versus lower canopy leaves along an altitudinal gradient. We tested the hypothesis that restrictive climatic conditions associated with high altitudes reduce within-canopy variations of leaf traits. The investigated beech (Fagus sylvatica L.) forest is located on the southern slope of the Hrubý Jeseník Mountains (Czech Republ...

Sera collected from 2,564 inhabitants of different areas in Hyogo Prefecture, Japan, were examined for antibody to Toxoplasma gondii by enzyme-linked immunosorbent assay. The overall prevalence rates of male (11.6%) and female populations (7.6%) were significantly different (P < 0.001). The prevalence also depended on age of the population. Of 11 districts three, being far from the sea and occu...

It is generally expected that inter-annual changes in radial growth among trees would be similar to the increase in altitude due to the limitation of increasingly harsher climatic factors. Here, we examine whether this pattern exists in alpine forests on the southeastern Tibetan Plateau. Increment cores were collected from mature trees at the lower, middle and upper limits of balfour spruce (Pi...

It is possible for medium-frequency (MF) radar systems to estimate kinetic energy dissipation rates by measuring signal fading times. Here, we present approximately 5 years of such results from Tromsø (69 N, 19 E) and in particular, investigate the periodicities present at different altitudes in the regime 80 to 100 km. We detect the known annual variation in the mesosphere and the semiannual v...

Observations by the Viking and Cluster satellites at altitudes up to 35 000 km show that Lower Hybrid Cavities (LHCs) are common in the inner magnetosphere. LHCs are density depletions filled with waves in the lower hybrid frequency range. The LHCs have, until recently, only been found at altitudes up to 2000 km. Statistics of the locations and general shape of the LHCs is performed to obtain a...

Water shortage is one of the most important environmental stresses in Mediterranean regions. Poor seedling quality may account for the failure of oak regeneration. To determine the best seed origin of Quercus brantii, we investigated on seedlings collected from 20 mother trees in the Zagros Mountain forests 700 to 2200 m altitudes above sea level. Seedlings from different altitudes were irrig...