![]() ![]() ![]() These discrepancies need further study to allow carbon export fluxes to be compared with confidence across laboratory, region and time and to achieve an improved global understanding of processes driving and controlling carbon export. We recommend that multiple methodologies to measure carbon export should be employed in field studies, to better account for each method’s merits and uncertainties. Only two deployments were possible during this study so caution should be taken when applying these findings to other regions and export regimes. This study highlights that the magnitude of particle fluxes and size spectra may be more sensitive than the chemical composition of particle fluxes to the instrumentation used. Parallel analytical determinations, conducted by different laboratories, of replicate samples for elemental fluxes and gel trap particle size distributions were comparable. Further comparisons are needed to distinguish if differences in particle flux magnitude are due to conical versus cylindrical trap designs. ![]() Cylindrical trap POC fluxes were of similar magnitude to ²³⁴Th-derived POC fluxes while conical POC fluxes were lower. In situ pump POC:²³⁴Th ratios generally agreed with trap ratios but conical trap samples were somewhat depleted in ²³⁴Th, which along with sinking particle size distribution data determined from gel traps, may imply under-sampling of small particles. Neutrally-buoyant conical traps appeared to collect lower absolute fluxes than neutrally-buoyant, or surface-tethered cylindrical traps, but compositional ratios of sinking particles indicated collection of similar material when comparing the conical and cylindrical traps. Samples were collected at the Porcupine Abyssal Plain Sustained Observatory (PAP-SO) site in the Northeast Atlantic Ocean (49°N, 16.5°W). This study compared samples from two neutrally buoyant drifting sediment trap designs, and a surface tethered drifting sediment trap, which collected sinking particles alongside other methods for sampling particle properties, including in situ pumps and ²³⁴Th radionuclide measurements. The aim of the study was to compare a suite of modern methods for measuring sinking carbon flux out of the surface ocean. Prior to this study, differing neutrally-buoyant sediment trap designs have not been deployed simultaneously, which precludes meaningful comparisons between flux data collected using these designs. Particle flux in the upper mesopelagic is often determined using sediment traps but there is no absolute standard for the measurement. Sinking particulate flux out of the upper ocean is a key observation of the ocean’s biological carbon cycle. Major questions yet to be addressed are also discussed including the difficulty of quantifying processes on the very limit of what we can model or observe and how these processes may change in response to and exert a feedback on future climate change. It is thought that this physical influence may play a major role in controlling the rate at which new plant material (primary production) is generated in much of the world's oceans. In particular, interplay between the physical circulation and biological processes results in constantly shifting patterns that are strongly related to changes induced in phytoplankton production. It is argued that the spatial variability seen in phytoplankton at these scales gives important information on the biogeochemistry of the ocean. Focus is then turned to the mesoscale, covering scales of roughly 1-500 km. A short history of observations of phytoplankton 'patchiness' is presented, illustrated with some of the many ideas put forward to explain it. At their most dramatic they paint colorful swathes across whole seas. Regardless of the scale at which they are observed, they display striking heterogeneity in their distribution. Some colors are more water resistant than others so be sure to test.Oceanic plant life is dominated by the microscopic phytoplankton. However, unlike regular polyester glitter it can handle only mild solvents (epoxy ok but test) and cannot handle prolonged sun exposure. This glitter works great with Mod Podge, white & clear glues, paste, high quality spray glues, on wet paint, and more. The polyester film is thinner than craft glitter making it more sparkly! We sell high quality fine Hybrid Glitter that is perfect for all sorts of projects for the classroom, after-school programs, church camps, sign makers, high school events, theatrical sets, parade floats & more (see below for a more complete list of applications). What is Hybrid Glitter? It is a polyester based glitter with less expensive craft glitter colorants and coatings. We have taken our best selling Hybrids and mixed them together into what we call Kaleidoscope Mixes! Add a touch of sparkle to all your favorite craft projects with our premium Hybrid Glitter. ![]()
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