soil productivity and plant growth are usually affected by biological activities of earthworms. the objective of this study was a comparative evaluation of earthworm abundances in 20-year-old plantations of alder, oak, maple and cypress with the adjacent natural mixed broad-leaved deciduous forest in the caspian region of iran. in this research one sample plot, each 1 ha; was selected in every ...

introduction: it was often believed that countries with natural resource abundance would undergo the process of development with a more accelerated pace in comparison to other countries. the experimental results, however, demonstrate a higher rate of success for countries which lack the said resources. the paradoxical effects of the possession, or a lack there of, natural resources on different...

investigation on structure and dynamics of natural forest ecosystems is an important issue for silvicultural decisions. the aim of this study is to analysis dynamics and structure of a beech stand during 5-year period in the shast kalateh forest in the caspian region, north of iran. data were collected from a 16.9ha permanent research plot established in a natural unlogged stand in 2006. all li...

land use change may influence many natural phenomena and ecological processes, including runoff, soil erosion, sedimentation and soil conditions. decreasing of forest area in the north of iran is one of the critical problems in recent years. the aims of this study are to detect land use changes between 1967 to 2002 using satellite images of land sat 7 etm+ (2002), aerial photos and digital topo...

The depletion of forest in developing countries due to extended pastures, agricultural land, fuel wood and etc. is a serious concern. Therefore planting trees for reforestation and extended forest area is a essential assignment. Forest plantation with a basic criterion affects to understory plant diversity. This effects may make some species absent or appear. The objective of this study is to a...