where Se is the eff ective saturation, h is the pressure head, θ is volumetric water content, θs and θr are saturated and residual volumetric water contents, respectively, and α and m (n = 1 − 1/m) are water retention parameters related to the water entry pressure and soil pore size distribution, respectively. Th e water retention parameters are usually estimated from water retention data obtai...

Based on the laboratory study, the effects of sodium polyacrylate (SP) was investigated at 5 rates of 0, 0.08, 0.2, 0.5, and 1%, on water retention, saturated hydraulic conductivity(Ks), infiltration characteristic and water distribution profiles of a sandy soil. The results showed that water retention and available water capacity effectively increased with increasing SP rate. The Ks and the ra...

In this study, we evaluated the efficiency of two types of biomass residues (fermentation residues from a bioethanol process, FB; brown mill residues from a papermaking process, BM) as amendments for a sandy soil. The characteristics of these residues including specific surface areas, morphologies and nutrient sorption capacity were measured. The effects of biorefinery residues on water and nut...

The mean annual transfer (loss and retention) of nitrogen in a river system was estimated using a conceptual approach based on water surface area and runoff. Two different approaches for the calculation of water surface area were applied to determine riverine nitrogen retention in four European catchments, ranging between 860-14,000 km2 in area, and differing considerably in the proportion and ...

Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespr...

the management of water table is introduced as one of the major parts of the solutions in water resources management. this method could play a significant role in protecting water resources, increasing irrigation efficiency, preserving nutrients in soil, and protecting the quality of surface downstream, and as well, of groundwater. towards this end, a laboratory study has been done on the effec...