Nowadays the study of regional groundwater resources, because of draught ,their optimal exploitation,and reducing their pollution is a vital matter. A proper way to prevent the pollution of undergroundwaters is to locate vulnerable spots and to conduct an efficient exploitation of the ground. Using thepresent models is very essential to locate and study about vulnerable spots. For this study, G...

near-surface environment. Also, many of the complicating effects found in the near-surface environment will Approaches for estimating liquid flux in the shallow (0–2 m) vadose be damped or eliminated with increasing depth. For zone are hindered by the high degree of spatial and temporal variability present near the land surface. It is hypothesized that high-frequency these reasons, flux measure...

A field study was initiated in 1992 to investigate the long-term impacts of beef feedlot manure application (composted and uncomposted) on nutrient accumulation and movement in soil, corn silage yield, and nutrient uptake. Two application strategies were compared: providing the annual crop nitrogen (N) requirement (N-based rate) or crop phosphorus (P) removal (P-based rate), as well as a compar...

The visions, directions, and images of soil science are changing. Historically, soil science has followed a circuitous path in its evolution from a discipline with foundational roots in geology, to an applied agricultural and environmental discipline, and now to a bioand geo-science through the Earth’s Critical Zone investigations. This closes the loop or spiral, but along the way, soil science...