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Persian oak (Quercus Brantii Lindl) is the most abundant tree species in Zagros mountain range that is affected by western dust storms and harsh droughts in recent years. The lack of spectral-temporal information about these trees has caused limitations on the usage of remote sensing images to make a synoptic estimation of damages caused by dust storms and drought. The objective of this research is to analyse the spectral-temporal behaviour of Persian oak under the stress of water deficiency and dust storms. The aim is to improve the competitive abilities of experts on modelling the stress of water deficiency and dust storms on trees using remote sensing images. For the purpose of this experimental investigation, a greenhouse laboratory has been built. Analysis of the experiments was carried out using 54 two-year-old oak tree seedlings; Fieldspec-3-ADD; and wind tunnel at the greenhouse of the faculty of agriculture of the Tarbiat Modares University in 2016. Results show that the water stress could be modelled much better using geometrical indices extracted from continuum removed spectrum. Area and the depth were best indices. Water stress has been modelled better that dust stress.

The use of bio-mulches to stabilize dust has gained worldwide attention during the last five decades. We report herein on a study of the application of 20 new types of bio-mulches as stabilizing agents. To understand the effect of new bio-mulches on dust stabilization, several tests have been applied for strength, structural stability and wind erosion. Fourier Transforms Infrared and Scanning Electron Microscopy have been applied on untreated and treated soil samples. Bio-mulch modified mechanisms have been analysed. Wind erosion and aggregate stability test results clearly indicate that certain biomulch specimens were useful in controlling dust in relatively arid and semiarid areas. The Scanning Electron Microscopy images show that when bio-mulches were applied to sandy soil, some voids in the soil were filled, while other parts stayed on the surface of soil aggregates. The molecular structure of polyelectrolyte groups reacted chemically with positive ions of the clay grain and created physicochemical bonds between molecules and soil aggregates with ionic, hydrogen or Vander Waals bonds. Untreated samples had no bonds between molecules and soil aggregate, and the strength and erosion resistance were weak. [ABSTRACT FROM AUTHOR]