solute transport processes are affected by soil pore water velocity distribution. pore size distribution, which can be used to infer pore water velocity distribution, can be estimated from a soil water retention curve (n). in this study, a solute breakthrough curve was simulated using soil hydraulic parameters in four different soils. to evaluate the proposed model, predictions were compared to...

In this research, investigation the impact of water levels, velocity on drift depth pillars bridges in Garmian region was studied. The levels and were recorded for periods, different stretches between months December 2018 March 2019. study dealt with most important postural relationships that can be used to estimate future around pillars. Description site studying within includes measurements b...

This research describes the goals, design and implementation of a quasi natural gradient, laboratory scale, sand tank (aquifer) model experiment. The model was used to study the transport of an inorganic tracer (Chloride) in groundwater, within a tropical aquifer (porous medium) material. Three-dimensional sand tank (1.8 m × 0.3 m × 0.8 m) experiments were conducted to investigate contaminant t...

Accurate characterization of near-surface soil water content is vital for guiding agricultural management decisions and for reducing the potential negative environmental impacts of agriculture. Characterizing the near-surface soil water content can be difficult, as this parameter is often both spatially and temporally variable, and obtaining sufficient measurements to describe the heterogeneity...

Adaptation of plants under drought and salinity stress depends directly on the type of soil texture. Therefore, in this research, the morpho-physiological variations of Stachys multicaulis, an Iranian wild endemic plant species, were investigated in different soil textures under drought and salinity stress. For this purpose, plants were cultivated in three different light, medium and h...

Previous work showed that remotely sensed soil moisture fields exhibit multiscaling and multifractal behavior varying with the scales of observations and hydrometeorological forcing (Remote Sens. Environ. 81 (2002) 1). Specifically, it was determined that this multiscaling behavior is consistent with the scaling of soil hydraulic properties and vegetation cover, while the multifractal behavior ...

A long-standing ambition in ecosystem science has been to understand the relationship between ecosystem community composition, structure and function. Differential water use and hydraulic redistribution have been proposed as one mechanism that might allow for the coexistence of overstory woody plants and understory grasses. Here, we investigated how patterns of hydraulic redistribution influenc...

soil water content is one of the most important parameters for estimating irrigation frequency and providing the plant’s water requirement. since measurement of soil water content is both expensive and time consuming, water movement models are used to estimate these values. in this study, leachw model was used to estimate soil water content for two “dry” (20-29 aug) and “wet” (1-6 jul) periods ...

The scaling theory approach has been widely used as an effective method to describe the variation of soil hydraulic properties. In conventional scaling, reference retention curves and scaling factors are determined from minimization of residuals. Most previous studies have shown that scaling factors are lognormally distributed. In this study, we derived physically based scaling factors, assumin...

in this work, 137cs activity concentration of soil in five depths and in six meteorology stations in terms of bq/kg has been measured. for each thirty soil's samples, parameters such as kind of soil, density and hydraulic coefficient of transmission were determined. correlation coefficient between 137cs activity concentration and raining average, hydraulic coefficient of transmission and s...