http://library.um.ac.id/free-contents/downloadpdf.php/buku/complexation-reactions-in-aquatic-systems-an-analytical-approach-j-buffle-translators-s-p-kounaves-a-kounaves-and-r-s-altman-12623.pdf

Complexation reactions in aquatic systems : an analytical approach / J. Buffle, translators S.P. Kounaves, A. Kounaves and R.S. Altman

Diel biogeochemical processes and their effect on the aqueous chemistry of streams: A review

We present a spatially explicit global overview of nearshore coastal types, based on hydrological, lithological and morphological criteria. A total of four main operational types act as active filters of both dissolved and suspended material entering the ocean from land: small deltas (type I), tidal systems (II), lagoons (III) and fjords (IV). Large rivers (V) largely bypass the nearshore filter, while karstic (VI) and arheic coasts (VII) act as inactive filters. This typology provides new insight into the spatial distribution and inherent heterogeneity of estuarine filters worldwide. The relative importance of each type at the global scale is calculated and types I, II, III and IV account for 32%, 22%, 8% and 26% of the global coastline, respectively, while 12% have a very limited nearshore coastal filter. As an application of this typology, the global estuarine surface area is re-estimated to 1.1 × 106 km2 instead of 1.4 × 106 km2 in earlier work.

/pdf/worldwide-typology-of-nearshore-coastal-systems-defining-the-4bnlmb6vhh.pdf

Worldwide typology of nearshore coastal systems: Defining the estuarine filter of river inputs to the oceans

Predicting the bioavailability of inorganic mercury (Hg) to bacteria that produce the potent bioaccumulative neurotoxin monomethylmercury remains one of the greatest challenges in predicting the environmental fate and transport of Hg. Dissolved organic matter (DOM) affects mercury methylation due to its influence on cell physiology (as a potential nutrient) and its influence on HgII speciation in solution (as a complexing agent), therefore controlling Hg bioavailability. We assessed the role of DOM on HgII bioavailability to a gram-negative bacterium bioreporter under oxic pseudo- and nonequilibrium conditions, using defined media and field samples spanning a wide range of DOM levels. Our results showed that HgII was considerably more bioavailable under nonequilibrium conditions than when DOM was absent or when HgII and DOM had reached pseudoequilibrium (24 h) prior to cell exposure. Under these enhanced uptake conditions, HgII bioavailability followed a bell shaped curve as DOM concentrations increased, ...

Dissolved organic matter kinetically controls mercury bioavailability to bacteria

Assessing the ecological status in the context of the European Water Framework Directive: Where do we go now?

Geochemical signals and source contributions to heavy metal (Cd, Zn, Pb, Cu) fluxes into the Gironde Estuary via its major tributaries.

https://www.epoc.u-bordeaux.fr/indiv/Anschutz/masson.pdf

Seasonal variations and annual fluxes of arsenic in the Garonne, Dordogne and Isle Rivers, France.

Budgets of Mn, Cd and Cu in the macrotidal Gironde estuary (SW France)

The diurnal evolution of the dynamic fraction, i.e., the potentially bioavailable fraction, of Cd, Cu, and Pb in a small river impacted by mining and smelting waste was studied in situ, under contrasting biofilm activity and hydrological conditions, using an automated voltammetric analyzer. The in situ, near real-time measurements revealed persistent dynamic metal species diurnal cycles. These cycles were affected mainly by the biochemical conditions rather than hydrological conditions. The data obtained from the in situ measurements, coupled with complementary laboratory analyses, revealed that various processes control the diurnal dynamic metal species cycles in the studied site; the trends of the diurnal cycles of the dynamic metal species can be different from those observed for the dissolved metal species measured in filtered samples. Moreover, the dynamic fraction of a given cationic metal can show diurnal cycles with opposite trends depending on the environmental conditions. All these findings highlight the interest and importance of automated, continuous measurements of specific relevant environmental metal fractions, compared to punctual weekly or monthly traditional sampling strategies of total dissolved metal analysis, to allow more appropriate water quality control and reliable assessment of metal ecotoxicological impact.

In situ monitoring of the diurnal cycling of dynamic metal species in a stream under contrasting photobenthic biofilm activity and hydrological conditions.

Matthieu Masson

Papers

Geochemical signals and source contributions to heavy metal (Cd, Zn, Pb, Cu) fluxes into the Gironde Estuary via its major tributaries.

Seasonal variations and annual fluxes of arsenic in the Garonne, Dordogne and Isle Rivers, France.

Budgets of Mn, Cd and Cu in the macrotidal Gironde estuary (SW France)

In situ monitoring of the diurnal cycling of dynamic metal species in a stream under contrasting photobenthic biofilm activity and hydrological conditions.

Behavior of arsenic and antimony in the surface freshwater reaches of a highly turbid estuary, the Gironde Estuary, France.