Knowledge of the quantitative and qualitative characteristics of changes in environmental planning, land- use planning and sustainable development is of great importance and today, the use of vegetation maps is one of the key pillars in information production for macro and micro- planning, and vegetation considered as one of the most important components of any ecosystem. Determining the percentage of vegetation in order to understand the interactions between the Earth and the atmosphere, its effect on climate, soil erosion, drought surveying, and natural resource management is essential. Since most of the methods proposed to assess drought conditions so far estimate drought indices based on stationary data at one point, researchers were looking for a way to better achieve regional estimates in order to better manage the damage caused by this gradual phenomenon. Therefore, in this research, remote sensing and Landsat 8 satellite imagery techniques and Infrared Percentage Vegetation (IPVI), Normalized Difference Vegetation Index (NDVI), Weighted Difference Vegetation Index (WDVI), Soil Adjusted Vegetation Index (SAVI), Optimized Soil Adjusted Vegetation Index (OSAVI) and Modified Soil Adjusted Index (MSAVI) were used to calculate the percentage of vegetation and the Modified Perpendicular Drought Index (MPDI) was used to estimate regional drought. After preparing the drought map, the areas which were in mild, moderate and severe drought in terms of severity, were well classified. پرونده مقاله

Prediction and estimation of runoff from snowfall and a quantitative understanding of its various production processes is considered as one of the important topics in hydrology. Therefore, the quantitative and qualitative achievement of it with a systemic approach in this regard is of importance since it forms the basis of studies of construction projects in various fields of development and exploitation in water resources and hydraulic structures and other environmental areas in the watersheds. Regarding the fact that snow cover represents the amount of stored water, so spatial-temporal (spatiotemporal) monitoring of snowmelt runoff is of great importance in hydrological forecasting in this region.The determination of the amount of snowmelt runoff is a function of regional characteristics and the availability of regional data. Therefore, in order to achieve this, ground operation and the creation of a denser network of snow survey stations are needed, which is almost impossible and is not economical. Therefore, in this study, in order to simulate runoff and estimate the share of snowmelt runoff in Marboreh River, simultaneously, optical satellite data and hydrological modelling of runoff are used as advantages. So that, snow product of the 8-day MODIS at 500-meter resolution was used to calculate the snow cover. Finally, the results obtained from runoff simulation by the coefficient of determination and subtracting volume, which were obtained at 0.93 and 3.48 respectively, indicate the high accuracy of the simulation for the area under study. پرونده مقاله