Gross sedimentation rates (GSR) were monitored together with the main characteristics of the collected matenal (i.e. organic content, C, N, total proteins, lipids, carbohydrates, available proteins and amino acids) over a 2 yr cycle at a shallow station (18 m) of the bay of Banyuls, France. In addition, sediment pigment concentrations and meiofaunal densit~es were recorded monthly during a 1 yr period. GSR ranged between 0.6 and 317.8 g DW m ' cl'' Spring and summer were characterized by relatively low and constant GSR whereas fall and wlnter were characterized by relat~vely high and hlghly variable GSR. There was a negatlve relationship between GSR and the organic content of material collected within the sediment traps, suggesting the importance of resuspension in controlling GSR. Growth rates of the deposit-feeding bivalve Abra ovata fed sediment trap material collected on 6 sampling dates were also measured. Significant changes in important nutrient components (e.g. available proteins) of sedimenting materials from these different sampling dates correlated with growth differences and confirmed the existence of temporal changes in the quality of the material collected in the sediment traps. The highest growth rate was obtained for the material collected during May 1993, which coincided with maximal meiofauna densities and maximal pigment concentrations at the surface of the sediment. The best descript.ion of growth was obtained when using available proteins and total lipids as the independent variables of simple linear regression models. This supports the use of these parameters as descriptors of food quality. The consequences of our results on the parameterization of changes in food quality within models of continental shelf food webs are discussed. It is suggested that such changes should be simulated through control functions based on available protein contents.
Several experiments were carried out to provide new information on the use of the 14C formaldehyde technique in deposit-feeding studies. Our results show that: (1) uptake and stability of labelling vary with specles and types of detritus, (2) there are significant differences between the labelling stabilities of uniformly and I4C formaldehyde labelled diatoms, (3) the use of uniformly and I4C formaldehyde labelled detritus derived from Pavlova lutheri results in very similar ingestion rates and absorption efficiencies by Abra ovata. (4) ingestion rates and absorption efficiencies of Abra ovata fed on 11 macrophytobenthic types of detritus labelled with I4C formaldehyde are consistent with the literature (negative relationship between ingestion and protein content, and between absorption and phenolic content), and (5) absorption efflclencies recorded for I4C formaldehyde labelled sediment trap materials collected at different periods of the year correlate negatively with gross sedimentation rates. These results support the use of the 14C formaldehyde technique with monospecific detritus. The relative values of absorption efficiencies recorded for heterogeneous detritus also seem consistent. However, it is stressed that the exactitude of the absolute values of these absorption efficiencies is yet to be proven.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.