(Riverstrahler and CaWaQs model) or on a specific river reach (ProSe model,
Anaqualand) (see Figs. 9 and 10 in [5]).
2.2.2 Territorial Metabolism: Comparing River Fluxes and Material
Circulation in the Anthroposystem
A major target of many biogeochemical and pollutant transfer studies is the establishment of annual to interannual material fluxes at selected river stations intercepting
different types of land use and pressures, providing time- and space-integrated
information on this territory. Fluxes can then be normalized by the intercepted area
to generate specific ones. Both specific fluxes and annual to interannual average
concentrations can be used to make comparisons within a basin, between river-borne
products, and comparisons between basins, thereby making it possible to understand
the spatial variability of these transfers and their controls.
The river fluxes can also be compared to the circulation of the targeted element
(e.g. nitrogen, cadmium, PCBs) within the anthroposystem (i.e. import–export,
product manufacturing, transportation and recycling of material, etc.). In theory, a
sustainable society should not release any waste into the environment, resulting in a
zero level of contamination. In reality, there is a continuous leak of waste into soils,
waterbodies or the atmosphere. The amount of material circulating over a given
territory is difficult to assess, since statistical data were not originally designed for
environmental objectives but rather for economic or fiscal purposes. The PIRENSeine is one of the pioneers in France on the contamination of the river system by
pharmaceuticals, particularly antibiotics [11]. This work has identified the sources
and transfers of these products in the Seine basin, linked to human wastewater
(hospitals, wastewater treatment plants) and to livestock farming. Moreover, the
circulation of products should be established over basins or sub-basins, i.e. with
hydrographic boundaries instead of administrative boundaries. Finally, the statistical
data relate to manufactured goods, not their chemical composition, which is what
would be needed for such a comparison, as in the case of individual metals,
pesticides and nutrients [12, 13]. Only few flux–flow comparisons have been made
for the Seine basin, providing precious information on the socio-hydrosystem
metabolism and its evolution over time. The ‘leakage rates’ of the basin have been
assessed for heavy metals, Cd, Cu, Hg, Pb and Zn, which ranged in the 2000s from
0.1 to 10%, depending on the metals [14] (see also [7] on sedimentary archives).
2.2.3 Aquatic Biota Contamination Across Trophic Levels: A Growing
Concern
At the outset of the programme, the aquatic species (phytoplankton, zebra mussel,
macrophytes) were studied as an important part of biogeochemical cycling or as
indicators of the overall water quality and its restoration. Fish ecology and its disturbance by multiple human impacts (organic pollution, habitat degradation, river flow
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C. Carré et al.
Anaqualand) (see Figs. 9 and 10 in [5]).
2.2.2 Territorial Metabolism: Comparing River Fluxes and Material
Circulation in the Anthroposystem
A major target of many biogeochemical and pollutant transfer studies is the establishment of annual to interannual material fluxes at selected river stations intercepting
different types of land use and pressures, providing time- and space-integrated
information on this territory. Fluxes can then be normalized by the intercepted area
to generate specific ones. Both specific fluxes and annual to interannual average
concentrations can be used to make comparisons within a basin, between river-borne
products, and comparisons between basins, thereby making it possible to understand
the spatial variability of these transfers and their controls.
The river fluxes can also be compared to the circulation of the targeted element
(e.g. nitrogen, cadmium, PCBs) within the anthroposystem (i.e. import–export,
product manufacturing, transportation and recycling of material, etc.). In theory, a
sustainable society should not release any waste into the environment, resulting in a
zero level of contamination. In reality, there is a continuous leak of waste into soils,
waterbodies or the atmosphere. The amount of material circulating over a given
territory is difficult to assess, since statistical data were not originally designed for
environmental objectives but rather for economic or fiscal purposes. The PIRENSeine is one of the pioneers in France on the contamination of the river system by
pharmaceuticals, particularly antibiotics [11]. This work has identified the sources
and transfers of these products in the Seine basin, linked to human wastewater
(hospitals, wastewater treatment plants) and to livestock farming. Moreover, the
circulation of products should be established over basins or sub-basins, i.e. with
hydrographic boundaries instead of administrative boundaries. Finally, the statistical
data relate to manufactured goods, not their chemical composition, which is what
would be needed for such a comparison, as in the case of individual metals,
pesticides and nutrients [12, 13]. Only few flux–flow comparisons have been made
for the Seine basin, providing precious information on the socio-hydrosystem
metabolism and its evolution over time. The ‘leakage rates’ of the basin have been
assessed for heavy metals, Cd, Cu, Hg, Pb and Zn, which ranged in the 2000s from
0.1 to 10%, depending on the metals [14] (see also [7] on sedimentary archives).
2.2.3 Aquatic Biota Contamination Across Trophic Levels: A Growing
Concern
At the outset of the programme, the aquatic species (phytoplankton, zebra mussel,
macrophytes) were studied as an important part of biogeochemical cycling or as
indicators of the overall water quality and its restoration. Fish ecology and its disturbance by multiple human impacts (organic pollution, habitat degradation, river flow
388
C. Carré et al.