the present study was carried out during a one year period in 2012-2013 in order to investigation of seasonal density and diversity of diplopoda in a hyrcanian forest (semeskandeh forest) in northern iran. for these purpose, some forest soil sampling were done in two mounth intervals and the samples were collected from leaf litter (ol,f,h), the 0-3 cm and 3-6 cm of soil layer (ah). a total of 7...

BACKGROUND Traits of non-dominant mixed-forest tree species and their synergies for successful co-occurrence in monodominant Gilbertiodendron dewevrei forest have not yet been investigated. Here we compared the tree species diversity of the monodominant forest with its adjacent mixed forest and then determined which fitness proxies and life history traits of the mixed-forest tree species were m...

In recent years, a remarkably simple physical picture of the Lyman-alpha forest has emerged, which allows detailed predictions to be made and turns the forest into a powerful probe of cosmology. We point out ways in which such a picture can be tested observationally, and explore three areas in which the Lyman-alpha forest can yield valuable constraints: the reionization history, the primordial ...

The flux/transmission power spectrum has become a popular statistical tool in studies of the high redshift (z > 2) Lyman-alpha forest. At low redshifts, where the forest has thinned out into a series of well-isolated absorption lines, the motivation for flux statistics is less obvious. Here, we study the relative merits of flux versus line correlations, and derive a simple condition under which...

Forest understories across the northern United States (US) are a complex of tree seedlings, endemic forbs, herbs, shrubs, and introduced plant species within a forest structure defined by tree and forest floor attributes. The substantial increase in white-tailed deer (Odocoileus virginianus Zimmerman) populations over the past decades has resulted in heavy browse pressure in many of these fores...

the zagros forests (west of iran) have been highly exploited in recent decades by human impacts. easy access, abundance and variety of valuable forest yields have led to population growth density, creation of new residential areas and deforestation activities. in order to determinate the distribution and rate of deforestation from 1995 to 2006 by using the satellite imagery (irs-1c and  landsat...

forests are an important economic source for human and have key role in nutrient cycle, hydrology and ecosystem performance, any interference in this vital ecosystem causes to damage to forests. mechanical logging and road construction in forest areas have led to much soil compaction. soil physical and chemical properties were studied in parts of road and non-road in the darabkola forest of ira...

one of the indicators of management and sustainability control of forest resources is the definition deforestation and degradation types. these factors hazard quantitative and qualitative of the iranian forests. in this study with integrated approach, different forms of forest degradation identified in the forest areas with a reviews of library resources and then investigation the degree of sta...