because soil moisture condition affects vegetation changes hence, monitoring of drought and vegetation changes are among valuable management tools in these ecosystems. nowadays, satellite images are used as a low-cost and fast method for vegetation study in different scales. vegetation change is assessed using vegetation spectral characteristics. this study aimed to analyze and monitor the vege...

Accurate canopy structure datasets, including canopy height and fractional cover, are required to monitor aboveground biomass as well as to provide validation data for satellite remote sensing products. In this study, the ability of an unmanned aerial vehicle (UAV) discrete light detection and ranging (lidar) was investigated for modeling both the canopy height and fractional cover in Hulunber ...

this study was carried out to investigate the effect of crown canopy of ziziphus spina-christi on seed bank characteristics (density and similarity with above ground flora) in two sites with saline-alkaline and alkaline soils. in each soil, forty plots were established, half in and half outside of z. spina-christi cover. in each plot, soil sampling was done from 0-5 and 5-10 cm depths. paired a...

abstract the objective of current research is to investigate distribution patterns of vegetation types and its relation with environmental factors in southern margin of haj aligholi kavir of damghan. three vegetation types including halecnemum strobilaceum, sedlitzia rosmarinus and artemisia sieberi were studied in marginal arid regions and uplands of the study area. firstly, geographic locatio...

The understory light environment is a key determinant of vegetation pattern and ecosystem processes, and varies spatially perhaps more than any resource used by plants. Understory light varies along gradients of vegetation structure that range from grassland with no woody canopy cover to forest with nearly complete woody canopy cover. Spatial variability in understory light is largely determine...

We evaluate the potential of deriving a vegetation leaf area index (LAI) from small footprint airborne laser scanning data. Based on findings from large area histograms of discrete laser returns for two contrasting plots, LAI is estimated from the fraction of first to last and single returns inside the canopy. The canopy returns are classified using thresholding of LIDAR raw data heights subtra...

Planting shrub seedlings under oil mulches has frequently been used for stabilizing mobile sands in Iran for during the last three decades. Sandy desert of Samad Abad, Sarakhs, northeast Iran, has been fixed by cultivating seedling of Haloxylon aphyllum under the oil mulches. Therefore this study was designed to investigate the effects of the sand fixation project on soil and vegetation propert...

Data collected from four distinct canopy positions from each of 39 Abies balsamea (L.) Miller trees were used to construct models to describe the cumulative leaf area distribution within the crown and to predict the needle mass of individual branches, the average branch angle, branch diameter, branch length, and crown radius per whorl, and the average number of living branches per whorl. We tes...