Anaerobic ammonium oxidation (anammox) is recognized as an important process for nitrogen cycling, yet little is known about its role in the subsurface biosphere. In this study, we investigated the presence, abundance, and role of anammox bacteria in upland soil cores from Tianjin, China (20 m depth) and Basel, Switzerland (10 m depth), using isotope-tracing techniques, (q)PCR assays, and 16 S ...

Abstract Tires waste is an undesirable urban industry surplus that has grown worldwide yearly. Because of its seals, this material may be used in earth dams, one option for disposing waste. Since the main objective study, experiment on a soil sample with various ratios rubber powder been conducted to better comprehend impact tire (TRP) seepage rate earthen dams. This study physical and numerica...

seepage analysis through earth dams is employed to determine the water loss. moreover, as the magnitude of pore pressure in dam body is calculated using seepage analysis, this analysis plays an important role on the stability analysis in these types of structures. as the hydraulic conductivity of the earth dam materials, is considered as one of the effective parameters on the magnitude of seepa...

Oscillatory well pumping was proposed recently as a tool for hydraulic tomography. Periodic pumping at a few frequencies is carried out through vertical intervals along the pumping well and the periodic head is measured along a few piezometers. The paper presents an analytical solution for the head field in an unconfined aquifer of finite depth under the common assumptions of a linearized water...

This paper discusses the design and practical use of efficient trajectories for an autonomous underwater vehicle. The vehicle model that will be presented is based on the NASA funded Deep Phreatic Thermal Explorer (DEPTHX) and the Omni-Directional Intelligent Navigator (ODIN). The underlying mathematical framework is developed using geometric control theory and differential geometry. Briefly, t...

The unsaturated zone and the saturated/unsaturated interface region are important links between groundwater and the land surface. They provide storage capacity for both water and contaminants; a reactor medium for physical, chemical and biological processes; a delay time between the release of a contaminant into the unsaturated zone and its influx into the saturated zone and, a domain for the l...