Seasonal variation in stable C and N isotope ratios of the Rhone River inputs to the Mediterranean Sea (2004–2005)

Harmelin-Vivien, Mireille; Dierking, Jan; Bănaru, Daniela; Fontaine, Marie-France; Arlhac, Denise

doi:10.1007/s10533-010-9411-z

Cited by 54 publications

(44 citation statements)

References 49 publications

(103 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To summarize, the development of phytoplankton in the river accounted for increased amount, higher lability and lower degradation state of sedimentary OM in February and April. A similar seasonal trend has been shown for the same area by Harmelin-Vivien et al (2010). Later, the flood that occurred in early June brought silty material originating from the weathering of soils.…”

Section: Discussionsupporting

confidence: 80%

River organic matter shapes microbial communities in the sediment of the Rhône prodelta

et al. 2014

View full text Add to dashboard Cite

Microbial-driven organic matter (OM) degradation is a cornerstone of benthic community functioning, but little is known about the relation between OM and community composition. Here we use Rhô ne prodelta sediments to test the hypothesis that OM quality and source are fundamental structuring factors for bacterial communities in benthic environments. Sampling was performed on four occasions corresponding to contrasting river-flow regimes, and bacterial communities from seven different depths were analyzed by pyrosequencing of 16S rRNA gene amplicons. The sediment matrix was characterized using over 20 environmental variables including bulk parameters (for example, total nitrogen, carbon, OM, porosity and particle size), as well as parameters describing the OM quality and source (for example, pigments, total lipids and amino acids and d 13 C), and molecular-level biomarkers like fatty acids. Our results show that the variance of the microbial community was best explained by d 13 C values, indicative of the OM source, and the proportion of saturated or polyunsaturated fatty acids, describing OM lability. These parameters were traced back to seasonal differences in the river flow, delivering OM of different quality and origin, and were directly associated with several frequent bacterial operational taxonomic units. However, the contextual parameters, which explained at most 17% of the variance, were not always the key for understanding the community assembly. Co-occurrence and phylogenetic diversity analysis indicated that bacteria-bacteria interactions were also significant. In conclusion, the drivers structuring the microbial community changed with time but remain closely linked with the river OM input.

show abstract

Section: Discussionsupporting

confidence: 80%

River organic matter shapes microbial communities in the sediment of the Rhône prodelta

et al. 2014

View full text Add to dashboard Cite

show abstract

“…δ 13 C and δ 15 N mean values found in TSM in the Rhône River are −27.1 ± 0.6 ‰ and 4.9 ± 1 ‰, respectively, which are within the range of those by Harmelin-Vivien et al (2010) in 2004 (δ 13 C: −26.6 ± 1.2 ‰ and δ 15 N: 5.7 ± 1.8 ‰) and 2005 (δ 13 C: −27.4 ± 1.4 ‰ and δ 15 N: 4.8 ± 1 ‰). These values are also similar to those found by Bȃnaru et al (2007) in the Danube River, the second largest river in Europe (δ 13 C: −27.5 ± 0.9 ‰ and δ 15 N: 4.9 ± 1.5 ‰).…”

Section: Sources Of Pom Transferred To the Nw Mediterranean Seasupporting

confidence: 75%

“…This high turbidity attenuates the photosynthetically available radiation (PAR) by producing a "shadow" effect. Harmelin-Vivien et al (2010) found that the autochthonous phytoplankton in the downstream part of the Rhône River accounted on average for only 10 % of the POM. For that reason, suspended particles of coastal rivers seem to be particularly more enriched in POM than the Rhône River (Table 2, Figs.…”

Section: Biogeosciencesmentioning

confidence: 99%

“…Riverine POM is habitually composed of a mixture of organic matter derived from autochthonous aquatic production and allochthonous terrestrial detritus of various origins (Maksymowska et al, 2000;Finlay and Kendall 2007;Harmelin-Vivien et al, 2010), which include vascular plants, soil-derived organic matter, freshwater algae and anthropogenic inputs. The proportions of each source vary according to the size of watershed, meteorological factors (such as the occurrence of storms) and land use.…”

Section: Sources Of Pom Transferred To the Nw Mediterranean Seamentioning

confidence: 99%

“…Indeed, carbon and nitrogen isotopic ratios (δ 13 C and δ 15 N) are widely used as natural tracers of carbon sources in riverine, estuarine and marine coastal ecosystems (Riera and Richard, 1997;Rolff and Elmgren, 2000;Darnaude et al, 2004;Wissel and Fry, 2005). In the NW Mediterranean, several studies on the Rhône River (Aucour et al, 2003;Darnaude et al, 2004;Harmelin-Vivien et al, 2010) determined the isotopic signatures of total suspended matter (TSM) within the range −27.4 to −26.1 ‰ for δ 13 C and 4.8 to 5.7 ‰ for δ 15 N. Recently, the suspended matter in coastal rivers Fluvià, Ter and Tordera has been isotopically characterized by a δ 13 C mean of 28 ‰ and a δ 15 N mean of 9.3 ‰ (Sanchez-Vidal et al, 2013).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Biogeochemical characterization of the riverine particulate organic matter transferred to the NW Mediterranean Sea

et al. 2014

View full text Add to dashboard Cite

Abstract.A large amount of terrestrial organic matter is annually delivered by rivers to the continental shelf, where this material is either degraded, buried or transferred to the deep sea by hydrodynamic processes such as storms. The relative amount of terrestrial organic matter in the marine sediments is often determined by analysing the stable isotopes (δ 13 C and δ 15 N) and the C / N ratio of organic matter because the various particulate organic matter (POM) sources have distinct isotopic compositions. With the objective to refine and better interpret POM sources in the marine environment, we have characterized monthly terrestrial POM delivered by eight rivers discharging to the NW Mediterranean Sea: the Rhône, Hérault, Orb, Aude, Têt, Fluvià, Ter and Tordera rivers. These rivers were simultaneously sampled from November 2008 to December 2009 and the concentrations of total suspended matter (TSM), particulate organic carbon (POC) and nitrogen (PN), as well as their stable isotopic ratios (δ 13 C and δ 15 N) were determined.During the survey, three rainstorm events with winds coming from the E-NE and the S-SE impacted the NW Mediterranean. Depending on the direction of incoming winds, the fluvial response (amount of water discharge and TSM) was different. Rivers draining the Alps (Rhône River) and Central Massif (Hérault, Orb, and Aude rivers) were mostly impacted by rainstorms associated with winds coming from the S-SE, while rivers draining the Pyrenees (Têt, Fluvià, and Ter rivers) and the Montseny Massif (Tordera River) were impacted by rainstorms associated with winds coming from the E-NE. In addition, the spatial evolution of water discharges shows a different hydrological regime of the Rhône River, with relatively constant and high water stages and TSM concentrations when compared to coastal rivers, characterized by long periods of low water stages. TSM concentrations are positively correlated to water discharges (high water flows resuspended riverbed sediments) but show an inverse relationship with POC and PN relative contents (mostly due to dilution and by low availability of light in river waters during flood events). TSM in most of the coastal rivers have on average 2.5-3 times higher POC and PN mean contents than the Rhône River (8.5 and 1.5 %, respectively, for coastal rivers compared to 3.6 and 0.5 %, respectively, for the Rhône River). This discrepancy may be caused by the long drought periods in small coastal Mediterranean watersheds that enhance the eutrophication in studied coastal rivers. The δ 13 C ratios of organic matter also reflect this discrepancy between high and low water stages with values ranging from −33.2 to −24.5 ‰. The enriched 13 C values (−26.3 ± 0.4 ‰ for the Rhône River and −26.9 ± 1.2 ‰ for coastal rivers), measured during high water stages, express mostly a mixture of terrestrial source (plant remains and soils) whereas

show abstract

Biomagnification of Mercury in Fish from Two Gold Mining-Impacted Tropical Marshes in Northern Colombia

Marrugo‐Negrete

Ruíz-Guzmán

Ruiz-Fernández

2017

Arch Environ Contam Toxicol

View full text Add to dashboard Cite

Total mercury concentrations (T-Hg) and stable isotope ratios (δN and δC) were analyzed in the muscle of fish, collected at two marshes impacted by gold mining in Northern Colombia, to evaluate the seasonal and spatial behavior of these variables and mercury biomagnification based on their relationship with δN ratios in the fish. There was not significant (p > 0.05) seasonal differences (dry and rainy season) in δN and δC values in none marsh, suggesting that these fish species keep a similar feed pattern within each marsh along the year. However, there were significant differences (p < 0.05) between marshes in δN, δC, and T-Hg, as well as significant seasonal differences (p < 0.05) in T-Hg values for some species, suggesting the possible influence of factors, such as differences in length of food chains between marshes and different degree of anthropogenic impact in relation to human settlements, farmland, livestock (higher in Ayapel marsh), and gold mining activity (higher in La Raya marsh). Correlations analysis showed significant (p < 0.05) relationships between T-Hg concentrations and δN values, as well as trophic level, evidencing a T-Hg biomagnification process in the fish food chain from both marshes and consequently a potential health risk for human riverside inhabitants who eat these fish.

show abstract

Seasonal variation in stable C and N isotope ratios of the Rhone River inputs to the Mediterranean Sea (2004–2005)

Cited by 54 publications

References 49 publications

River organic matter shapes microbial communities in the sediment of the Rhône prodelta

River organic matter shapes microbial communities in the sediment of the Rhône prodelta

Biogeochemical characterization of the riverine particulate organic matter transferred to the NW Mediterranean Sea

Biomagnification of Mercury in Fish from Two Gold Mining-Impacted Tropical Marshes in Northern Colombia

Contact Info

Product

Resources

About