Sharif Digital Repository

Drought is a common phenomena which has a lot of unwanted conse-quences on human being life and environment. Drought forecasting plays a significant role in water resources and environmental systems. Considering IRAN inappropriate location which is on the arid and semi-arid area of the earth and Widespread damages which are related to drought during recent years in iran; importance of developing an accurate model by using new technologies becomes quite inevitable. In the last decay Neural Networks have appeared very useful in non-Stationary and non-linear time Series forecasting and modeling.
This study is about to use conjunctive model of adaptive neuro fuzzy inference system and... 

Using a combination of groundwater and surface water, is defined as each project planned by combining these two sources which, in most cases, will achieve greater benefits than the non-integrated. The benefit is a set of privileges that technically, economically and environmentally justify the project. One of the prevalent and effective problems of fertile and flat plains of Khuzestan province, especially the Evan plain, is lack of proper drainage of agricultural land downstream of dams and irrigation networks which are covered by. In this plain also, according to statistics from Piezometers, the groundwater level is rising. At the first, the aim of this study is to study the current... 

Iran is regarded as a dry land and has suffered from extreme to severe drought conditions in recent years. Drought – which is mainly caused by shortage in rainfall – affects the normal life in Iran. Development of tools for effectively monitoring and predicting drought intensity might help the policy makers to reduce the vulnerability of the areas affected by drought. In this thesis, we showed that the intensity of drought can be predicted using satellite imagery data and recurrent neural networks. To this end, the standardized precipitation index (SPI) was chosen as an index for drought and normalized deviation of vegetation index (NDVI) as a remote sensing measure extracted from NOAA-AVHRR... 

The extended drought in the Orumieh River Basin has caused severe problems for Orumieh Lake. Due to the fact that agriculture is the biggest user of water resources in this region, effective management of groundwater and surface water resources plays an important role in management of Orumieh lake`s condition. In this situation, “water trading” by designing an efficient “smart market” seems to be a viable option; A market with lower transaction costs which can be adaptable to changing demands and being able to optimize economic benefit within the environmental constraints. This market works by reallocating water among users who intend to sell their excess water and those who prefer to buy... 

The phenomenon of drought causes many damages which is not limited to arid and semi-arid areas and may have destroying effects on groundwater resources of any region. To investigate the drought effects on one of the Lake Urmia’s sub-basin, the precipitation data in 25 rain stations in period of 45 years (2011-1976) was used. After completing and restoring data, and checking the randomness and homogeneity of them, standardized precipitation index (SPI) with different time scales has been calculated. According to that, the monitoring maps of drought using ArcGIS tool with regard to best interpolation method was created in order to identify the sensitive areas in dry years.
Moreover,... 

In many regions of Iran, arid and semiarid climate and increase of water consumption, lead water managers to use optimal operating of water resources systems. During periods of drought, when inflows to the reservoir are low, it may not be possible to satisfy the target delivery (planned demand), and shortage occurs. Also, During periods of drought, the underground water resource’s pollution and inordinate consumption of underground water resources, increase density of water pollution. These reasons always appoint water resource planner to develop models for determine optimal surface water resource operating rules. Using of hedging rules that are attended by many researchers in these... 

Empirical finding and evidence asserts that families, in response to income shock, allegedly use their children as income sources and have them to participate in the labor market. By making use of Propensity Score Matching and Heckman Two Steps models and exogenous agricultural income shocks, we examine the hypothesis for the families in the rural areas of Iran. We use the Households' Income and Expenditures Survey of Iran for two consequent years of 1393 (2014) and 1394 (2015). The working sample is restricted to households with children aged between 10-17 years old. Our findings show that the outcome of interest, daily work hours, is not significantly affected by the exogenous shocks of... 

The classical approaches of drought analysis are performed using historical records and univariate statistical methods. In the use of historical records it is assumed that statistical characteristics of droughts will be exactly repeated in the future (the assumption of stationarity) and in the use of univariate methods it is assumed that drought variables (e.g. duration and severity) are independent; while on the contrary, global warming changes long-term climate patterns, which is called climate change, and also drought variables have significant correlation. Thus, results of classical approaches of drought analysis have uncertainties.The primary objective of this thesis is to propose an... 

The objective of this dissertation is to develop a model to monitor and project the long-term changes in meteorological drought under climate change at watershed scale. In this model, drought is defined based on joint precipitation-temperature values since negative correlation between precipitation and temperature implies that drier periods are often warmer, and therefore, the consequences of drought are more severe compared to low-precipitation periods with mild temperature. This is of particular importance considering global warming. To quantify drought, an indicator called precipitation-temperature deciles index, which is an extension of precipitation deciles index, is introduced. Copula... 

The relationship between the environment and human life has long been considered by researchers. Technological growth in the last century, by the intensification of natural resources usage, led to environmental degradation, and thus the importance of recognizing the relationship between human life and the environment has doubled. The present dissertation is organized in three chapters, in each of which we investigate the impacts of a dimension of environmental degradation on human well-being.In the first chapter, we investigate the effect of drought on expenditure and income per capita of Iranian households. To do this, we combine the expenditure and income data of more than 600,000 urban...