مجله مخاطرات محیط طبیعی
پیاپی 3 (بهار 1392)

Iran due to high climatic variability, was always exposed to various natural hazards.
One of the disaster, avalanche areas is Brfkhyz in place, considerable damage has been inflicted on the body of the Economic and Social.
Therefore, the preparation of maps for different parts of the area on February evaluate risks is very important. In this paper, by using maps of elevation, slope, aspect, land use and geomorphology and climatic factors, and considering the avalanche field visit any part of the basin was Which shows the high capabilities of geographic information systems in the avalanche is to identify pathways. The results of this study showed that seventeen crossing the Persian month Bahman identified six pathways regulating basin, Roads and residential areas that affect administrators should make necessary arrangements for controlling the crossings.

Most of the seismic activities in north-east of Iran are observed around the major fault systems which have mostly been distributed along the approximate direction of NW-SE. Fractal analysis was performed in north-eastern Iran by the method square-counting for the sake of which the study area was classified into 12 regions and each region was analyzed separately. Fractal dimension is ranged between 0 and 2. If Fractal dimension is approximate 0, it will indicate that the faults and earthquakes have been centered in one place. If Fractal dimension is approximate 2, it will indicate that the faults and earthquakes have been dispersed in the area. In fact, this comparative method is a vibrated action among neighbor areas. Based on the results by distancing from the main fault systems in the region that possesses the trend of NW-SE, The fractal dimension of seismicity is reduced .This indicates the existence of discontinuity in the major fault systems in the region. The high rate of fractal dimension of the regions of same Qaen, Boshruyeh and Torbat – e –Heydarieh as well as the reduction in the rate of the fractal dimension of the blocks of Birjand, Gazik and Taybad, suggest that the terminal area of the major fault systems in the east is located in the area of Taybad and Birjand blocks. On the basis of Fractal analysis of the fault zone and the study of the seismic data, most of the seismic activity in the north - East of Iran is based on the pattern of intercontinental earthquakes of low depth (mostly between 10-20 km) and occurs in relation to the primary linear sources (faults) in the area or their secondary branches. The distribution of voluminal and superficial fractal dimension of the East of Iran Also, indicates the higher seismic activity in the central and western parts in regard to other adjacent.

Identification of effective factor on mass movement events and risk zoning is one of the basic tools for mass movement control and appropriate and effective option. Thus, the aim of this study is recognizing effective factors on mass movement and determination hypothetical lands, then pay to mass movement mapping in West Azarbaijan province.
For this reason first of all, important effective factor on mass movement event were determinate. In this study, most mass movement data were obtained base on direct observation. In field study, phenomena location, its approximate measuring, hillside material sampling and region determination was perform.
Then, using over laying, accruing different instability zones, field observations and expert opinions deal with to zoning different mass movement in West Azarbaijan province. For this reason Arc­ GIS and Arc View were used. One of another option in this study is adjusting the phenomena with satellite and aerial picture.
The results show that the solifluction and Creeping with about 757898.8 hectare covers almost 20 percent of western Azarbaijan province. Also among the different towns in the province the most probable mass movement is related to Khoy. This mass movement over than 556092.29 hectare approximately includes 14.7 percent of the total mass movements of the western Azarbaijan province.

To doing this research, daily minimum and maximum temperature data from 11 synoptic stations and 15 climatology stations on the in and out of Kurdistan province during 1/1/1962 to 31/12/2010 have been used. Data interpolated on 6 by Kriging interpolation method. The 811 pixels obtained that cover the whole of the province. Two data base in 17898 811 pixels have been created that located days on the rows and pixels on the columns. The 16 extreme temperature indices of Expert Team of Climate Change Detection and Indices (ETCCDI) have been used. For each pixel the 16 indices calculated and evaluated significant trend by non-parametric Mann-Kendal method in the 95% confidence level. The trend slope estimated by liner regression. To doing spatial analysis, the trend and slope rate changes for each indices have been shown in separate maps. The results of this study showed that extreme warm indices are increasing over the low lands and extreme cold indices are decreasing over the heights and mountains. The positive trend for extreme warm indices observed in the west, southwestern and semi-eastern parts of the province. The spatial extent of increasing warm nights is more than warm days. The cold extremes are increasing on the heights and decreasing over the low lands and floor plains. The durnal temperature range(DTR) has been decreased. The changes rate of extreme minimum temperature is more than daily extreme temperature changes.

Identification of areas susceptible of landslide is one of the primary measures in managing and reducing the damage caused by such phenomena. In this regard, according to the goal and environmental conditions, different zoning models have been proposed. In order to zone and study the areas susceptible of landslides in the north of Neyshaboor, AHP method was applied. Thus, factors causing landslides including slope, lithology, land use, rainfall, the distance from river, the distance from the fault and the distance from the road were analyzed as the main factors for the occurrence of landslide. Layers of information related to each of the factors effective in the occurrence of landslides were prepared by the means of GIS analysis, and effective factors were evaluated using the AHP and paired comparisons. Finally the landslide hazard zonation map was prepared. Considering the final weight of each of the factors, it was concluded that the slope of the landslide and lithology in this area are the first and second most important factors influencing the landslide degree. Also the results of this zoning and the existing distribution of landslides confirmed that places susceptible of landslide in this region are based on landslide areas.

To doing this research, daily minimum and maximum temperature data from 11 synoptic stations and 15 climatology stations on the in and out of Kurdistan province during 1/1/1962 to 31/12/2010 have been used. Data interpolated on 6 by Kriging interpolation method. The 811 pixels obtained that cover the whole of the province. Two data base in 17898 811 pixels have been created that located days on the rows and pixels on the columns. The 16 extreme temperature indices of Expert Team of Climate Change Detection and Indices (ETCCDI) have been used. For each pixel the 16 indices calculated and evaluated significant trend by non-parametric Mann-Kendal method in the 95% confidence level. The trend slope estimated by liner regression. To doing spatial analysis, the trend and slope rate changes for each indices have been shown in separate maps. The results of this study showed that extreme warm indices are increasing over the low lands and extreme cold indices are decreasing over the heights and mountains. The positive trend for extreme warm indices observed in the west, southwestern and semi-eastern parts of the province. The spatial extent of increasing warm nights is more than warm days. The cold extremes are increasing on the heights and decreasing over the low lands and floor plains. The durnal temperature range(DTR) has been decreased. The changes rate of extreme minimum temperature is more than daily extreme temperature changes.