drought is transient phenomenon , slow , repetitive and integral part of the climate of each region. drought begins with a substantial reduction in precipitation over the long-term average rainfall and over time, reduced soil moisture and surface and ground water resources will continue to decrease. this phenomenon is the most important in bakhtegan basin because of its importance in strategic ...

after the soviet union dissolution, a chaotic period was begun in the russia. russia lost its glory and felt disgrace. the first group of elites came to power under yeltsin; they tried to re-define russia’s identity as a european country and build a foreign policy on this baseline. therefore russia tried to become closer with the west especially with the u.s. according to their view the sovie...

Base-flow can be considered as a part of stream-flow which is connected to discharged flow from aquifers. Due to high variations in rainfall values and other hydrological components in arid and semi-arid areas, watershed scale simulation of the flow is very important. Hydrological models are generally employed as an appropriate tool in this field of study. This work makes uses of use a distribu...

all analytical methods are generally based on the measurement of a parameter or parameters which are somehow related to the concentration of the species.an ideal analytical method is one in which the concentration of a species can be measured to a high degree precision and accuracy and with a high sensitivity. unfortunately finding such a method is very difficult or sometimes even impossible.in...

The SIMDualKc model is an irrigation scheduling simulation model that uses dual crop coefficient method for estimating ETc by computing two separate soil water balances in daily time-step, one for the soil evaporation layer from which Ke is computed, and the other one for the entire root zone to compute the actual Kcb adjusted to the soil moisture conditions. In this study, lysimetric measureme...