lysimeter tests were conducted on shallow groundwater that supplies part of the maize water requirements to determine crop yield. twenty-four 0.8 m diameter lysimeters were buried in the test field at a depth of 1.2 m. the lysimeters were filled with the field soil (silty loam) and planted with summer maize. the groundwater depth in the lysimeters was set at 0.6 m using marriotte bottles. three...

limitation of water resources in iran motivates sustaining and preserving of the resources in order to supply future water needs. fulfilling these objectives will not be possible unless having accurate water balance of watersheds. the purpose of this study is to estimate the water balance parameters using a distributed method. the large number of distributed models and methods was studied and “...

 The factors that determine the success of the crop is water content in the soil profile explored by the roots, where soil and management condition affect the storage and availability. Because of the sites defined by the altimetry and crops predecessors affect the behavior of water content stored in the soil available for plants.  The aim of this work was to analyze the relationship between d...

To assess the influence of stream water on leaf gas exchange and water potential in different sized boxelder trees (Acer negundo L.), we compared these characteristics in trees growing beside a perennial stream and a nearby ephemeral stream in a montane-riparian forest in northern Arizona. Patterns of tree water use were quantified by stable isotope analysis (delta(18)O). Physiological characte...

in order to investigate effect of deficit irrigation on phenological stages and yield of soybean cultivars, an experiment was conducted as split plots based on randomized complete block design with three replications at agricultural research farm, university of guilan in 2009. main factor was included four irrigation levels based on potential moisture 30-35 (i1), 50-55 (i2), 70-75 (i3) centibar...

Iodine deficiency disorders (IDDs) refer to the spectrum of consequences of iodine deficiency in a population resulting from its deficit in soil and water. Consumption of crops and plants grown on iodine-deficient soils leads to IDD in populations solely dependent on this vegetation for their iodine requirements. When iodine intake falls below the recommended levels, the thyroid may no longer b...