faraz estelaji; alireza abasi semnani; ehsan alipouri
Abstract
Evaluation and planning of crisis management with natural disaster approach includes many components. In this regard, one of the basic pillars of construction management is based on resilience. With this view, attention to planning and research priorities of our country shows the present and future. ...
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Evaluation and planning of crisis management with natural disaster approach includes many components. In this regard, one of the basic pillars of construction management is based on resilience. With this view, attention to planning and research priorities of our country shows the present and future. Construction management in flood-prone areas is one of the most important priorities for studies and planning for sustainable development in the country. According to the studies conducted, the study area is one of the flood-prone areas and according to the floods, damages have occurred. We have witnessed a lot of lives and infrastructure in this area. A review of the construction of settlements in the study area shows that with the approach of construction management, many constructions have been carried out and are being carried out in this area. There are many challenges from the crisis management approach. The opinion is the method and nature of survey and exploration. In this regard, in this article, Lorestan flood zoning has been done in GIS system and strategies to increase productivity have been presented
leila abdollahi; Mohammad Faraji; ali haghizadh; Somayeh Dehdari
Abstract
Abstract The effects of droughts on surface water and groundwater resources reduce the amount of water available to different sectors. Hydrological drought initially begins with decreasing rainfall and is usually associated with lower levels of lakes and reservoirs. To this end, in order to ma ke appropriate ...
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Abstract The effects of droughts on surface water and groundwater resources reduce the amount of water available to different sectors. Hydrological drought initially begins with decreasing rainfall and is usually associated with lower levels of lakes and reservoirs. To this end, in order to ma ke appropriate management decisions to prevent the harmful effects of drought, it is necessary to assess the characteristics of this phenomenon by assessing and monitoring the drought. In this research, the time series analysis and SDI shaking technique were used to evaluate the hydrological drought at the hydrometric station at the Marian River during the period from 1982 to 2015. The results of hydrological drought on the sunshine station showed that the highest frequency of droughts was related to mild droughts with 29.41% and severe drought with 11.74% and medium drought of 2.94%. Also, the results of self-correlation series analysis, which showed significant correlation for all months except Azar, before the analysis of its effect was removed by Hamed and Rao (modified by Mann-Kendal), and in December, the ordinary Mann-Kendall test used. In all months of the station, except for the month of Aban and Azar (non significant), during the period of 1982-2015, gradual changes are significant at 5% level, and the sudden changes of the time series are significant at 5% level and have a decreasing trend. Also, the results of the Paty's homogeneity test showed that the sudden changes in the time series were significant at all levels at the 5% level.
Alirostam Khanizadeh; Reza Erfanzadeh; Reza Siahmansur
Abstract
The aim of this study was to quantify the response of Bromus tomentellus, Hordeum bulbosum and Agropyron trichophorum to continuous grazing of sheep in semi-arid rangelands of Lorestan. In two areas, grazed and ungrazed, 4 transects of 200 meters were established and 10 random points were selected along ...
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The aim of this study was to quantify the response of Bromus tomentellus, Hordeum bulbosum and Agropyron trichophorum to continuous grazing of sheep in semi-arid rangelands of Lorestan. In two areas, grazed and ungrazed, 4 transects of 200 meters were established and 10 random points were selected along of each transect and at each point the nearest plant considered for further study. Morphological traits of each selected plant were measured i.e. height, internode distance, root length, root weight, production and mass. After reviewing the data normalization, the averages between grazed and ungrazed were compared by non-paired t-test. The effect of livestock grazing on height, shoot internode, length and root weight, biomass and yield of H. bulbosum and A. trichophorum were significant. The mean weight of H. bulbosum in the ungrazed and grazed areas was 117.1 gr and 16.1 gr, respectively, and the height of A. trichophorum was 525.1 mm in the ungrazed and 334.7 mm in the grazed areas, respectively. Grazing of livestock had no significant effect on the height and internode distance of B. tomentellus (p>0.05). Animal grazing significantly increased root length of 58.35 mm in B. tomentellus. In general, the results of this study showed that different species of plants exposed different reactions and trade-off against grazing depending on the type of plant species. Knowledge about of the morphological changes of plant species against grazing can greatly help us for the management of sustainable grazing in the rangelands.
