Fecal indicator bacteria (FIB) indicative of fecal contamination in urban streams and recreational ocean beaches in Santa Barbara, California often exceed recreational water-quality standards. During low flow, FIB and human-specific Bacteroides concentrations in urban streams were associated with point discharges. FIB concentrations varied three-fold during diurnal sampling as a result of small...

Offshore activities often encounter large scale sand patterns, such as sand waves. Sand waves are offshore bed forms occurring at water depths of 10 to 50 m. Their wavelengths can lead up to 500 m and their heights are typically several metres. Furthermore, sand waves have been shown to migrate, with typical velocities of up to metres per year. These dynamic sand waves decrease the least naviga...

BACKGROUND Beach sand can harbor fecal indicator organisms and pathogens, but enteric illness risk associated with sand contact remains unclear. METHODS In 2007, visitors at 2 recreational marine beaches were asked on the day of their visit about sand contact. Ten to 12 days later, participants answered questions about health symptoms since the visit. F+ coliphage, Enterococcus, Bacteroidales...

Previous research has shown that the temperature of underlying permafrost decreases after the ground surface is covered with sand. No significant conclusions have yet been drawn that explain why this happens, because the heat transfer mechanism effects of the sand layer on the underlying permafrost remain unclear. These mechanisms were studied in the present work. We found that the upward short...

In the evolution processes of wind blown sand movement and aeolian geomorphology, it always contains some complex behaviors, for example, the nonlinear character of turbulence and attractors, the stochastic character of wind gust, liftoff and movement of sand, the interaction among wind field, sand movement, electric field in wind blown sand flux and thermal diffusion, multi-scale character fro...

Straw checkerboard barrier (SCB) is the most representative antidesertification measure and plays a significant role in antidesertification projects. Large-eddy simulation and discrete-particle tracing were used to numerically simulate the wind sand movement inside the straw checkerboard barrier (SCB), study the movement characteristics of sand particles, find the transverse velocities of sand ...

Keywords: Groundwater seepage Pedotransfer function ROSETTA Seepage erosion Uncertainty analysis s u m m a r y Research has suggested that streambank seepage can be an important mechanism of bank instability; however, limited information is available on the level of soil characterization necessary to accurately predict seepage gradient forces and erosion. The objective of this research was to q...

Plastic waste poses a significant hazard to the environment as result of its high production rates, which endanger both and inhabitants. Similarly, another concern is cement, accounts for roughly 8% global CO2 emissions. Thus, recycling plastic replacement cementitious materials may be more effective strategy minimisation cement elimination. Therefore, in this study, (low-density polyethylene) ...

We study the evolution of a one-dimensional pile, empty at rst, which receives a grain in its rst stack at each iteration. The nal position of grains is singular: grains are sorted according to their parity. They are sorted on trapezoidal areas alternating on both sides of a diagonal line of slope p 2. This is explained and proved by means of a local study. Each generated pile, encoded in heigh...

for optimum planning, utilization, and management of lands, recognition of spatial variability of soil properties is necessary. this research was conducted to evaluate spatial variability of soil properties in 5000 ha of arsenjan plain in fars province. for this purpose, soil salinity, ph, particle size percentage, sodium, potassium, and organic carbon (oc) were measured on a systematic squared...