The concept of root contact hypothesizes that the absorbing roots grown in sandy soil are only partially effective in water uptake. Co-ordination of water supply and demand in the plant requires that the capacity for water uptake from the soil should correspond to an operational rate of water loss from the leaves. To examine how the plant hydraulic system responds to variations in soil texture ...

abstarct precise knowledge of all components of water balance is essential to optimize water use in irrigated agriculture. however, water balance components are difficult to measure in required time intervals because their measuring is time consuming and costly. unsaturated zone simulator models are useful tools for predicting the effects of agricultural management on crop water use and can be ...

[1] The focus of this study is on the role of precipitation uncertainty in the estimation of soil texture and soil hydraulic properties for application to land-atmosphere modeling systems. This work extends a recent study by Santanello et al. (2007) in which it was shown that soil texture and related physical parameters may be estimated using a combination of multitemporal microwave remote sens...

The desiccation of upper soil horizons is a common phenomenon, leading to a decrease in soil microbial activity and mineralization. Recent studies have shown that fungal communities and fungal-based food webs are less sensitive and better adapted to soil desiccation than bacterial-based food webs. One reason for a better fungal adaptation to soil desiccation may be hydraulic redistribution of w...

Soil absorption systems (SAS) are used commonly to treat and disperse septic tank effluent (STE). SAS can hydraulically fail as a result of the low permeable biomat zone that develops on the infiltrative surface. The objectives of this experiment were to compare the hydraulic properties of biomats grown in soils of different textures, to investigate the long-term acceptance rates (LTAR) from pr...

The objectives of the study were to identify the relevant hydraulic parameters associated with stomatal regulation during water stress and to test the hypothesis of a stomatal control of xylem embolism in walnut (Juglans regia x nigra) trees. The hydraulic characteristics of the sap pathway were experimentally altered with different methods to alter plant transpiration (Eplant) and stomatal con...

Soil moisture memory is a key component of seasonal predictability. However, uncertainty in current memory estimates is not clear and it is not obvious to what extent these are dependent on model uncertainties. To address this question, we perform a global sensitivity analysis of memory to key hydraulic parameters, using an uncoupled version of the H-TESSEL land surface model. Results show sign...

Methods to predict soil hydraulic properties frequently require information on the particle size distribution (PSD). The objectives of this study were to investigate various protocols for rapidly measuring PSD using the laser diffraction technique, compare the obtained PSD with those determined using the traditional hydrometer-and-sieves method (HSM), and assess the accuracy of soil hydraulic p...

a pressure-based coupled heat and mass transfer model was used to simulate temperature and soil suction in a drying process within a clay soil column. closed form functions were used for all parameters needed in the governing equations. model predictions were compared with experimental data using the mean relative percentage deviation method. thermocouples and mini-gypsum blocks were used t...

oped (Wind, 1968; Becher, 1971; Boels et al., 1978; Schindler, 1980; Tamari et al., 1993; Wendroth et al., Soil hydraulic properties are important parameters affecting water 1993; Halbertsma and Veerman, 1994). flow in variably saturated soils. We estimated the hydraulic properties from a laboratory evaporation experiment using both a parameter An important modification was suggested by Wind es...