gradual intensification and specialisation of agricultural systems are associated with
increased opening of the nutrient cycles and growing environmental losses, even
though a significant reduction in fertiliser over-use has been observed since the
1980s as a result of agro-environmental regulations (Figs. 1, 8 and 9).
This link is suitably illustrated by two contrasted scenarios for the French
agriculture at the horizon 2040, established by Billen et al. [50]. One of these
scenarios assumes the pursuit of the trends towards opening to the global market
and specialisation of territorial agricultural systems observed over the last 50 years,
with, however, compliance to current agro-environmental regulations. The second
scenario depicts an alternative option where generalisation of agroecological practices, reconnection of crop and livestock farming and of local food production and
consumption, and a change in the human diet towards a Mediterranean diet with a
much lower contribution of meat and milk allow a high level of autonomy of the
agro-food system of the Seine watershed with respect to industrial and long-distance
trade inputs. It was shown that both scenarios can feed the French population at the
2040 horizon and still export a significant amount of cereals, with, however, quite
different environmental impacts. Only the latter scenario is able to halve GHG
emissions [35] and to improve nitrate (and pesticide) contamination of groundwater
and surface water [50]. It has also been shown that solving problems caused by
noxious algal blooms in coastal marine waters at the outlet of large, human-impacted
river systems would require this type of paradigmatic change in the structure of the
agro-food systems [10, 51].
Acknowledgements This work was carried out in the scope of the PIREN-Seine programme,
supported by the Seine-Normandie Water Agency and several other partners, and could benefit from
the scientific context of the LTSER Zone Atelier Seine managed by the French National Center for
Scientific Research (CNRS).
References
1. Le Noë J, Billen G, Lassaletta L, Silvestre M, Garnier J (2016) La place du transport de denrées
agricoles dans le cycle biogéochimique de l’azote en France: un aspect de la spécialisation des
territoires. Cah Agric 25:15004. https://doi.org/10.1051/cagri/2016002
2. Meybeck M, de Marsily G, Fustec É (1998) La Seine en son bassin, Fonctionnement écologique
d’un système fluvial anthropisé. Elsevier, Paris
3. Billen G, Garnier J, Mouchel J-M, Silvestre M (2007) The Seine system: introduction to a
multidisciplinary approach of the functioning of a regional river system. Sci Total Environ
375:1–12
4. Le Noë J, Billen G, Garnier J (2017) How the structure of agro-food systems shapes nitrogen,
phosphorus, and carbon fluxes: the generalized representation of agro-food system applied at
the regional scale in France. Sci Total Environ 586:42–55. https://doi.org/10.1016/j.scitotenv.
2017.02.040
The Seine Watershed Water-Agro-Food System: Long-Term Trajectories of C. . .
111
increased opening of the nutrient cycles and growing environmental losses, even
though a significant reduction in fertiliser over-use has been observed since the
1980s as a result of agro-environmental regulations (Figs. 1, 8 and 9).
This link is suitably illustrated by two contrasted scenarios for the French
agriculture at the horizon 2040, established by Billen et al. [50]. One of these
scenarios assumes the pursuit of the trends towards opening to the global market
and specialisation of territorial agricultural systems observed over the last 50 years,
with, however, compliance to current agro-environmental regulations. The second
scenario depicts an alternative option where generalisation of agroecological practices, reconnection of crop and livestock farming and of local food production and
consumption, and a change in the human diet towards a Mediterranean diet with a
much lower contribution of meat and milk allow a high level of autonomy of the
agro-food system of the Seine watershed with respect to industrial and long-distance
trade inputs. It was shown that both scenarios can feed the French population at the
2040 horizon and still export a significant amount of cereals, with, however, quite
different environmental impacts. Only the latter scenario is able to halve GHG
emissions [35] and to improve nitrate (and pesticide) contamination of groundwater
and surface water [50]. It has also been shown that solving problems caused by
noxious algal blooms in coastal marine waters at the outlet of large, human-impacted
river systems would require this type of paradigmatic change in the structure of the
agro-food systems [10, 51].
Acknowledgements This work was carried out in the scope of the PIREN-Seine programme,
supported by the Seine-Normandie Water Agency and several other partners, and could benefit from
the scientific context of the LTSER Zone Atelier Seine managed by the French National Center for
Scientific Research (CNRS).
References
1. Le Noë J, Billen G, Lassaletta L, Silvestre M, Garnier J (2016) La place du transport de denrées
agricoles dans le cycle biogéochimique de l’azote en France: un aspect de la spécialisation des
territoires. Cah Agric 25:15004. https://doi.org/10.1051/cagri/2016002
2. Meybeck M, de Marsily G, Fustec É (1998) La Seine en son bassin, Fonctionnement écologique
d’un système fluvial anthropisé. Elsevier, Paris
3. Billen G, Garnier J, Mouchel J-M, Silvestre M (2007) The Seine system: introduction to a
multidisciplinary approach of the functioning of a regional river system. Sci Total Environ
375:1–12
4. Le Noë J, Billen G, Garnier J (2017) How the structure of agro-food systems shapes nitrogen,
phosphorus, and carbon fluxes: the generalized representation of agro-food system applied at
the regional scale in France. Sci Total Environ 586:42–55. https://doi.org/10.1016/j.scitotenv.
2017.02.040
The Seine Watershed Water-Agro-Food System: Long-Term Trajectories of C. . .
111