existing and planned physical modifications of the fluvial system, thus shaping its
trajectories:
Urban development, perfectly documented since the seventeenth century for
Versailles chateau, gardens and city, results in major transformations of stream
orders 1–3. In the nineteenth and twentieth centuries, the spatial and demographic
expansion of Paris and its surroundings have also generated major changes in
medium-sized urban streams (orders 2–4) [17].
The intensification of agriculture has largely modified first-order streams,
converted into ditches to which underground tile drains are connected.
The intensification of navigation has been continuous since 1830, resulting in
multiple transformation of the river channel in orders 5–8. It is largely driven by the
urban development of Paris and by the export of agricultural products from the Seine
basin. This activity is still progressing.
The demand for sand and gravels, extracted from the Seine, Marne and Oise
floodplains, has been generated by urban and infrastructure development after 1950
and has reshaped the landscape of the alluvial plains.
River flow regulation and flood security have already resulted in the construction
of large reservoirs able to double or triple the natural Seine River flow at Paris in
summer and reduce the flood stage. New water storage facilities are now planned in
the Bassée floodplain, finalising the physical transformation of the major wetland of
the Seine Basin, already impacted by sandpits and river channelisation.
Unlike many pollutions caused by the Paris region, which have decreased or have
been treated since 1960 or 1970 (see the following chapters), the physical modifications of the river network, channel and floodplain, and of its related habitats that
have taken place in the last 200 years, are mostly irreversible, at least for order 5–7
rivers.
Today, many actors – river and water users, decision-makers and citizens – have a
stake in the balance between river biodiversity and good ecological state, flood risk
control, recreational uses and economic uses: some of these uses control the rivers’
future, others react and adapt. For these reasons, the Seine River basin and its
society is a typical example of a territory in the Anthropocene era, where society
has gradually and permanently controlled a major part of the natural system [63].
Aside from physical control, other examples of biochemical, chemical or ecological
controls are presented and illustrated in the following chapters.
Further applications of this work, which has required the identification of numerous archives over the past 8 years, during the previous phases of the PIREN-Seine
programme, already include the evolution of obstacles to migratory fish and the
identification of sediment archive storage sites to reconstruct trajectories of contaminants in the Seine basin [54]. One may also consider integrating the vertical
evolution of the channel into the groundwater/surface water exchange models (see
[64]). When focusing on the socio-economic and ecological consequences of river
evolution, we can see that the entire extent of alluvial plains is in fact impacted.
Specific studies, based on the same methodology of quantitative analysis of historical maps, will be carried out in the next phase of the PIREN-Seine project
(2020–2023) to describe trajectories of the river corridor as a whole.
The Evolution of the Seine Basin Water Bodies Through Historical Maps
53
trajectories:
Urban development, perfectly documented since the seventeenth century for
Versailles chateau, gardens and city, results in major transformations of stream
orders 1–3. In the nineteenth and twentieth centuries, the spatial and demographic
expansion of Paris and its surroundings have also generated major changes in
medium-sized urban streams (orders 2–4) [17].
The intensification of agriculture has largely modified first-order streams,
converted into ditches to which underground tile drains are connected.
The intensification of navigation has been continuous since 1830, resulting in
multiple transformation of the river channel in orders 5–8. It is largely driven by the
urban development of Paris and by the export of agricultural products from the Seine
basin. This activity is still progressing.
The demand for sand and gravels, extracted from the Seine, Marne and Oise
floodplains, has been generated by urban and infrastructure development after 1950
and has reshaped the landscape of the alluvial plains.
River flow regulation and flood security have already resulted in the construction
of large reservoirs able to double or triple the natural Seine River flow at Paris in
summer and reduce the flood stage. New water storage facilities are now planned in
the Bassée floodplain, finalising the physical transformation of the major wetland of
the Seine Basin, already impacted by sandpits and river channelisation.
Unlike many pollutions caused by the Paris region, which have decreased or have
been treated since 1960 or 1970 (see the following chapters), the physical modifications of the river network, channel and floodplain, and of its related habitats that
have taken place in the last 200 years, are mostly irreversible, at least for order 5–7
rivers.
Today, many actors – river and water users, decision-makers and citizens – have a
stake in the balance between river biodiversity and good ecological state, flood risk
control, recreational uses and economic uses: some of these uses control the rivers’
future, others react and adapt. For these reasons, the Seine River basin and its
society is a typical example of a territory in the Anthropocene era, where society
has gradually and permanently controlled a major part of the natural system [63].
Aside from physical control, other examples of biochemical, chemical or ecological
controls are presented and illustrated in the following chapters.
Further applications of this work, which has required the identification of numerous archives over the past 8 years, during the previous phases of the PIREN-Seine
programme, already include the evolution of obstacles to migratory fish and the
identification of sediment archive storage sites to reconstruct trajectories of contaminants in the Seine basin [54]. One may also consider integrating the vertical
evolution of the channel into the groundwater/surface water exchange models (see
[64]). When focusing on the socio-economic and ecological consequences of river
evolution, we can see that the entire extent of alluvial plains is in fact impacted.
Specific studies, based on the same methodology of quantitative analysis of historical maps, will be carried out in the next phase of the PIREN-Seine project
(2020–2023) to describe trajectories of the river corridor as a whole.
The Evolution of the Seine Basin Water Bodies Through Historical Maps
53