A laboratory study has been carried out on two soil layers (H[X] and H[Y]) located above a groundwater table in Yaounde, Cameroon (Central Africa). The main purpose of this study was to assess the retention potential or sorption kinetics of Escherichia coli and Salmonella sp. on these soil layers. For both soil layers, bacterial sorption on soil particles occurred rapidly during the first 30 mi...

This paper examines the effects of soil moisture initialization in a coupled air quality–meteorological model on temperature profiles, wind speeds, and pollutant concentrations. Three simulations, each with different initial soil moisture fields, were run. In the baseline simulation, predicted temperatures, wind speeds, and gas/aerosol pollutant concentrations accurately matched observations. I...

Microbial community dynamics associated with manure hot spots were studied by using a model system consisting of a gel-stabilized mixture of soil and manure, placed between layers of soil, during a 3-week incubation period. The microbial biomass, measured as the total amount of phospholipid fatty acids (PLFA), had doubled within a 2-mm distance from the soil-manure interface after 3 days. Princ...

the effects of dominant shrub species on soil organic matter (som), including total soil carbon (sc), total nitrogen (n) and particulate organic matter (pom) were studied in three stands differing in the type of shrub species, i.e. astragalus microcephalus (shrub), pteropyrum aucheri (shrub) and prangus uloptera (non-shrub).the stands were located in arid grasslands of north-western iran. for t...

Once released, manure-borne bacteria can enter runoff via interaction with the thin mixing layer near the soil surface. The objectives of this work were to document temporal changes in profile distributions of manure-borne Escherichia coli and enterococci in the near-surface soil layers after simulated rainfalls and to examine differences in survival of the two fecal indicator bacteria. Rainfal...

estimated effective precipitation (pe) in dryland areas is an essential element of water resource management. itrepresents the amount of precipitation available in the crop root zone to meet the needs of evapotranspiration. thecurrent study compared different approaches for estimating pe in different climatic zones of iran. a two-layer soil–water balance (swb) model was adopted based on the pro...

Nitrogen (N) limitation is common in most terrestrial ecosystems, often leading to strong competition between microorganisms and plants. The mechanisms of niche differentiation to reduce this competition remain unclear. Short-term (15)N experiments with NH4(+), NO3(-), and glycine were conducted in July, August and September in a temperate grassland to evaluate the chemical, spatial and tempora...

Using ®eld mesocosms maintained for 6 months in an acid spruce forest, we investigated the in ̄uence of microarthropods on biomass, structure and function of the soil microbial community. In the litter layer (L/F layer), the re-immigration of mesofauna into mesocosms did not signi®cantly a€ect substrate-induced respiration (SIR), biomass C, biomass N, biomass P, Nmineralisation or enzymes involv...

Shallow landslides on steep (>25) hillsides along Puget Sound have resulted in occasional loss of life and costly damage to property during intense or prolonged rainfall. As part of a larger project to assess landslide hazards in the Seattle area, the U.S. Geological Survey instrumented two coastal bluff sites in 2001 to observe the subsurface hydrologic response to rainfall. The instrumentatio...