overgrazing, via harvesting of forage species and decrease the other herbs, is of progressive factors in biodiversity destroying. in order to investigate the animal grazing impacts on changing of plant structure and diversity, we selected the comparison between this effect with exclosure area, and proving of the excluded area effects on plant diversity; two sites of kojour rangeland, mazandran ...

Mangrove forests are one of the most productive and carbon dense ecosystems that are only found at tidally inundated coastal areas. Forest canopy height is an important measure for modeling carbon and biomass dynamics, as well as land cover change. By taking advantage of the flat terrain and dense canopy cover, the present study derived digital surface models (DSMs) using stereo-photogrammetric...

Impaired water quality caused by human activity and the spread of invasive plant and animal species has been identified as a major factor of degradation of coastal ecosystems in the tropics. The main goal of this study was to evaluate the performance of AnnAGNPS (Annualized NonPoint Source Pollution Model), in simulating runoff and soil erosion in a 48 km watershed located on the Island of Kaua...

Quantifying tree canopy cover is fundamental to applications in forestry and ecology, but estimates vary substantially depending on type of field measurement, imagery, or active sensing used. Our objective was improve stand-level from standard inventory measurements, using representative data collected across diverse forest plant association groups Oregon, USA. Canopy measured with line interce...

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...

Although there are several parameters of interest in the quantitative aspects of vegetative remote sensing, leaf area index (LAI) has been one of the most useful and important parameters to characterize the vegetation activities from local to global scales. LAI, defined as the sum of the leaf area per unit ground area, can be used to measure the activities (photosynthesis, transpiration, and ev...

In order to study the effects of three operations of rangelands on the properties of vegetation in rangelands, this research was conducted in Chaat Gonbad, Golestan province, Iran in 2004. Chaat area is located in 50 km of border road of Dashlibroun to Maravetappeh in North of Attract River (border of Iran and Turkmenistan). The Altitude is 70 m, annual rainfall is 170 mm and annual temperature...

Small pollutant concentration gradients between levels above a plant canopy result in large uncertainties in estimated air–surface exchange fluxes when using existing micrometeorological gradient methods, including the aerodynamic gradient method (AGM) and the modified Bowen ratio method (MBR). A modified micrometeorological gradient method (MGM) is proposed in this study for estimating O3 dry ...