Stream-bed sediments from three paired catchments, each draining a lower agricultural intensity system and a higher agricultural intensity system, were analysed for (a) total P (TP), (b) bioavailable-P (Resin-P), (c) equilibrium phosphorus concentration (EPC0), and (d) degree of phosphorus saturation (DPS). The influence of agriculture on sediment P was explored within the context of other key ...

Indirect photometric chromatography and microdistillation enabled a simultaneous measurement of sulfate depletion and sulfide production in the top 3 cm of freshwater sediments to be made. The simultaneous measurement of sulfate depletion and sulfide production rates provided added insight into microbial sulfur metabolism. The lower sulfate reduction rates, as derived from the production of aci...

Infdtration rate and sediment production were measured over a 2-year period on an intensive rotationally grazed pasture. Measurements were taken prior to the movement of livestock onto the pasture, soon after their removal, and approximately midway through the subsequent rest period of each rotation through the system. Midgrass-dominated interspaces were characterized by significantly higher ht...

Irradiance is attenuated rapidly in benthic microalgal mats. This makes it difficult to quantify the relevant light field for the benthic community, which is a necessary parameter for accurate primary production estimates. Photosynthesis of microphytobenthos on estuarine mudflats can be measured using variable fluorescence techniques and can be expressed as relative linear photosynthetic electr...

Abstract The bacterial activity in sediments is often low considering the generally high bacterial abundance. Still, a large fraction of bacteria have been found active even in deep sediments. These findings suggest that sediment bacteria have comparatively low cell-specific production. We studied bacterial activity and the active fraction of bacteria in a lake sediment profile. Bacterial produ...

The environmental impacts arising from mining activities affect the air, water, and soil quality. Impacts may result in unexpected and adverse environmental outcomes. This study reports on the impact of coal production on sediment in Sydney region of Australia. The sediment samples upstream and downstream from the discharge points from three mines were taken, and 80 parameters were tested. The ...

Aquaculture is growing rapidly in response to an increasing demand for protein and the over-exploitation of wild fisheries. Mussel (family Mytilidae) production has doubled over the last decade and currently stands at 1.5 million tones production per annum. Mussels produce organic biodeposits which are dispersed around the production site and, potentially, impact the receiving environment in a ...

The Delaware Estuary has a history of high anthropogenic nutrient loadings but has been classified as a highnutrient, low-growth system due to persistent light limitation caused by turbidity. While the biogeochemical implications of light limitation in turbid estuaries have been well-studied, there has been minimal effort focused on the connectivity between hydrodynamics, sediment dynamics, and...

A set of GIS tools has been developed (Road Sediment Analysis Model, RSAM) to analyze and quantify the impacts of forest roads on forested watersheds. RSAM is organized into three modules. In the first module sediment production for each road segment is calculated from slope, length, road surface condition and road side drain vegetation. A GPS gathered road condition inventory provides surface ...

Survival and settlement of Pocillopora damicornis larvae on hard surfaces covered with fine (<63 µm) terrigenous red clay was measured in laboratory Petri dishes. The dishes were prepared with sediment films of various thicknesses covering the bottoms. Coral larvae were incubated in the dishes for two weeks and the percent that settled on the bottom was determined. There was a statistically sig...