Launched in 2010, the RhoMéO project ultimately aims to set up an observatory for monitoring the ecological status of wetlands in the Rhone basin. For this reason, a study was conducted that among other goals aimed at quantifying the overall agricultural, urban and road development pressures in and around a certain number of wetland test sites.
An overlay analysis of satellite images and other data sources in GIS (Database BD-Topo of the National Geographic Institute, Registry of Agricultural Land by the Ministry of Agriculture) was performed. Overlaying data from these various sources allows us to quantify the anthropogenic pressure within a wetland, or in its immediate catchment area (within 100 m or 500 m radius, for example).
To illustrate this point, we can take the example of the immediate vicinity (a buffer of 100 m width) of the 48 test wetlands in the Provence region. The chart (on the right column) shows that the sample sites cover a wide range of possible situations, from wetlands where most of the area is agricultural (left), to those whose surroundings are highly urbanized (Site 18 for example.), to sites with little evidence of human impact (right). Note that this sample is not necessarily representative of the situation of all wetlands in the region.
We can also synthesize this information spatially, on a map. By grouping the values of the major categories of human impact we obtain the map on the right column.
The repetition of these measurement will allow for the regular updating of the state of these pressures in the test sites and will demonstrate the expected improvement of the state of the wetlands in the catchment in a an easily comparable spatial manner.
This study in line with the Mediterranean Wetlands Observatory agenda that include measuring pressures on wetlands in order to explain changes over time, and to seek solutions to limit or stop negative impact on them.
For further information, please contact:
Christian Perennou: perennou@tourduvalat.org
or
Anis Guelmami: guelmami@tourduvalat.org
