The Use of Sediment Traps in High-Energy Environments

White, James V.

doi:10.1007/978-94-009-0615-0_12

Cited by 15 publications

(15 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is of concern to the coral reef research community, for sediment tube traps are commonly used by many researchers and regulatory agencies to determine "sedimentation rates" (e.g., Almada-Villela et al, 2003;Hill and Wilkinson, 2004). The findings presented here, along with previous studies (Gardner et al, 1983;White, 1990;and Jurg, 1996;Storlazzi et al, 2004;Bothner et al, 2006), suggest the following: (a) Sediment traps should have greater than a 10:1 length-to-width ratio, and all traps used within a study should have the same size and ratio; and (b) All sediment traps in a study should be deployed with their traps openings at a similar height above the seabed. In locations where current and wave-orbital speeds are sufficient to resuspend the adjacent seabed material, the trap collection rates must be analyzed in the context of the site's hydrodynamics to determine if the trapped material resulted from local resuspension or advected from some other location.…”

Section: The Application Of Sediment Traps To Coral Reef Environmentsmentioning

confidence: 53%

Sedimentation processes in a coral reef embayment: Hanalei Bay, Kauai

et al. 2009

View full text Add to dashboard Cite

a b s t r a c t a r t i c l e i n f oOceanographic measurements and sediment samples were collected during the summer of 2006 as part of a multi-year study of coastal circulation and the fate of terrigenous sediment on coral reefs in Hanalei Bay, Kauai. The goal of this study was to better understand sediment dynamics in a coral reef-lined embayment where winds, ocean surface waves, and river floods are important processes. During a summer period that was marked by two wave events and one river flood, we documented significant differences in sediment trap collection rates and the composition, grain size, and magnitude of sediment transported in the bay. Sediment trap collection rates were well correlated with combined wave-current near-bed shear stresses during the non-flood periods but were not correlated during the flood. The flood's delivery of fine-grained sediment to the bay initially caused high turbidity and sediment collection rates off the river mouth but the plume dispersed relatively quickly. Over the next month, the flood deposit was reworked by mild waves and currents and the fine-grained terrestrial sediment was advected around the bay and collected in sediment traps away from the river mouth, long after the turbid surface plume was gone. The reworked flood deposits, due to their longer duration of influence and proximity to the seabed, appear to pose a greater long-term impact to benthic coral reef communities than the flood plumes themselves. The results presented here display how spatial and temporal differences in hydrodynamic processes, which result from variations in reef morphology and orientation, cause substantial variations in the deposition, residence time, resuspension, and advection of both reef-derived and fluvial sediment over relatively short spatial scales in a coral reef embayment.Published by Elsevier B.V.

show abstract

Section: The Application Of Sediment Traps To Coral Reef Environmentsmentioning

confidence: 53%

Sedimentation processes in a coral reef embayment: Hanalei Bay, Kauai

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Each trap consisted of a 30-cm long PVC pipe with an internal diameter of 5.08 cm and a plastic cap tightly affixed to one end. Accordingly, length was approximately six times greater than diameter, which is above the minimum 5:1 ratio needed to prevent re-suspension of trapped sediments in high-energy wave and current environments (White 1990, Storlazzi et al 2011. The traps were fastened, open end facing upwards at a height of 1 m above the bed, to a thin (1.9 cm in diameter) metal rod secured to a 15-kg cinder block placed horizontally on the bed.…”

Section: Waterborne Sedimentsmentioning

confidence: 99%

Mechanisms of stability of rhodolith beds: sedimentological aspects

Millar¹,

Gagnon²

2018

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Rhodolith beds are highly diverse benthic communities organized around the physical structure and primary productivity of red coralline algae. Despite a worldwide distribution and growing recognition that rhodolith beds are important calcium carbonate (CaCO3) biofactories, little is known of the factors and processes that regulate their structure, function, and stability. One prevalent and largely untested paradigm is that beds develop in environments where water motion is strong enough to prevent burial by sediments.Observations over seven months and three weeks in the centre and near the upper and lower margins of a Newfoundland rhodolith (Lithothamnion glaciale) bed, as well as a laboratory mesocosm experiment with rhodoliths and dominant macrofauna from the bed, were used to characterize, parse, and model spatial and temporal variation in rhodolith sediment load (RSL) and movement among presumably important abiotic and biotic factors. RSL and movement were largely mediated by a few dominant benthic invertebrates. Hydrodynamic forces were insufficient to displace rhodoliths. Daisy brittle stars (Ophiopholis aculeata) and small common sea stars (Asterias rubens) contributed to dislodgement of sediment from rhodoliths. Large green sea urchins (Strongylocentrotus droebachiensis) easily displaced rhodoliths in mesocosms. Results provide the first quantitative demonstration that rhodolith beds need not be exposed to threshold hydrodynamic conditions to avoid burial. Beds can simply occur in areas where burial is unlikely because of low sedimentation rates. In such cases, select resident bioturbators operating simultaneously at different spatial scales (within and outside rhodoliths) appear to suffice to maintain RSL below lethal quantities, contributing to stability of beds.iii ACKNOWLEDGEMENTS

show abstract

“…The sampling interval was set to 7 days during the first deployment Table 1). Collection efficiency of sediment traps depends on the flow velocity, the trap shape and aspect ratio (height/diameter), the tilt, and the settling velocity of particles (Baker et al, 1988;White, 1990;Buesseler, 1991 and reference therein). Despite hydrodynamic biases associated with intermittent strong currents and tilt, and different trap designs (conical and baffled PPS5 versus unbaffled cylindric PPS3), the similarities of temporal variability of near-bottom fluxes at the different sites suggests that data are robust enough to draw conclusions on the overall seasonal and interannual variability of downward particle fluxes in the study area.…”

Section: Sediment Trap Time Seriesmentioning

confidence: 99%

Impact of open-ocean convection on particle fluxes and sediment dynamics in the deep margin of the Gulf of Lions

et al. 2013

View full text Add to dashboard Cite

The deep outer margin of the Gulf of Lions and the adjacent basin, in the western Mediterranean Sea, are regularly impacted by open-ocean convection, a major hydrodynamic event responsible for the ventilation of the deep water in the western Mediterranean Basin. However, the impact of open-ocean convection on the flux and transport of particulate matter remains poorly understood. The variability of water mass properties (i.e., temperature and salinity), currents, and particle fluxes were monitored between September 2007 and April 2009 at five instrumented mooring lines deployed between 2050 and 2350-m depth in the deepest continental margin and adjacent basin. Four of the lines followed a NW–SE transect, while the fifth one was located on a sediment wave field to the west. The results of the main, central line SC2350 ("LION") located at 42°02.5′ N, 4°41′ E, at 2350-m depth, show that open-ocean convection reached mid-water depth (≈ 1000-m depth) during winter 2007–2008, and reached the seabed (≈ 2350-m depth) during winter 2008–2009. Horizontal currents were unusually strong with speeds up to 39 cm s<sup>−1</sup> during winter 2008–2009. The measurements at all 5 different locations indicate that mid-depth and near-bottom currents and particle fluxes gave relatively consistent values of similar magnitude across the study area except during winter 2008–2009, when near-bottom fluxes abruptly increased by one to two orders of magnitude. Particulate organic carbon contents, which generally vary between 3 and 5%, were abnormally low (≤ 1%) during winter 2008–2009 and approached those observed in surface sediments (≈ 0.6%). Turbidity profiles made in the region demonstrated the existence of a bottom nepheloid layer, several hundred meters thick, and related to the resuspension of bottom sediments. These observations support the view that open-ocean deep convection events in the Gulf of Lions can cause significant remobilization of sediments in the deep outer margin and the basin, with a subsequent alteration of the seabed likely impacting the functioning of the deep-sea ecosystem

show abstract

The Use of Sediment Traps in High-Energy Environments

Cited by 15 publications

References 18 publications

Sedimentation processes in a coral reef embayment: Hanalei Bay, Kauai

Sedimentation processes in a coral reef embayment: Hanalei Bay, Kauai

Mechanisms of stability of rhodolith beds: sedimentological aspects

Impact of open-ocean convection on particle fluxes and sediment dynamics in the deep margin of the Gulf of Lions

Contact Info

Product

Resources

About