to identify an appropriate index for monitoring and evaluation of drought, rainfall data obtained from meteorological stations of ilam province from 2000 to 2011 and modis satellite images with 16-day intervals were collected and processed. the standardized precipitation index (spi) was calculated based on rainfall data; therefore, the rainfall data were used for measuring spi and satellite ima...

study of soil and plant relationships is nessesery for ecological- based and appropriate management. the objective of this study is to determine the influence of edaphic properties on haloxylon persicum growth and also, indentifing growth limiting soil properties for saxaul. the study was performed through the stratified random sampling and 3 sites were selected as follow: planted strong saxaul...

The aim of this study was to assess the regional effects of fire on the surface cover and forage production of mountainous rangelands of Delfan County, Lorestan province, Iran. The fire took placed in June 2007 with significant effects on the vegetation characteristics in the study area. Four fire affected sites were selected for sampling and a close area without fire was considered as control....

Growth and productivity of plants are mainly affected by various environmentalfactors in different ecosystems and natural habitat in the world. This research aims to studythe existing relationships between the phytosociology characteristics of Thymuskotschyanus and environmental factors in order to find the most important factorsgoverning development of the species in middle Taleghan rangelands...

To detection of suitable sampling method to study tree canopy cover in the northern Zagros forest, Baneeh region forest, Kurdistan province, and west of Iran was selected. 40 square sample plots one hectare (100×100 m) were selected and perfect inventoried. In every sample plot the position of tree, kind of species and two diameter of crown (m) were recorded. To study of canopy cover different ...

Woody plant encroachment into grasslands and rangelands is a world-wide phenomenon but detailed descriptions of changes in geographical distribution and infilling rates have not been well documented at large land scales. Remote sensing with either aerial or satellite images may provide a rapid means for accomplishing this task. Our objective was to compare the accuracy and utility of two types ...

introduction soil is one of the most valuable national resources that can be wasted by erosion phenomenon. therefore, prevention of soil erosion is universally considered. erosion is a process by which soil particles are separated from their original context and can be moved to another location. rill erosion is a kind of water erosion in which detachment and movement of soil particles can be af...

environmental characteristics, including the quality of green spaces, constitute one of the determinants of buildings (house & apartment) transaction prices. in this research, impact of urban green space on building's transaction prices (rials/m2) in karaj region, district 1 (jahanshahr), was analyzed. therefore, a questionnaire concerning building characteristics and transaction prices wa...