The Study site consists of 2 areas in Brittany, namely the Semnon catchment area the Oust-Ninian catchment. These areas are presented separately below.

Semnon catchment area 

Geographical description

Semnon catchment area is localized at the south of Ille-et-Vilaine department, in the eastern part of Brittany. It size is around 495 km2 and 26. 000 hectares of total cultivated area. Semnon river is 73 km long. The geology of the area is quite homogeneous. It consists of alternating 2 types of schists, between which are intercalated sandstone and sandstone foundations.

The Semnon catchment descends west to its confluence with the Vilaine river, where its altitude is about ten meters. Its maximum altitude is about 100 meters, in the south-eastern part. The Semnon catchment is subject to an oceanic climate, with a gradient to a continental climate in the eastern part, with result in less continuous rains than in coastal areas.

SemnonLocationMap
 Location of the Semnon catchment area.

Pedo-climatic zone
Lusitanian/ Atlantic Central, Cambisol

Cropping systems

Cropping intensity
Semnon catchment area has 434 farms and it is mainly a dairy area. There are 18 organic farms on the area. FRAB and his local partner Agrobio35 are working on soils with more or less 12 farms in this area (organic and conventional)

Types of crop
Wheat, maize and grassland : the territory has mainly traditional dairy systems : grassland systems and maize based systems. Most of the farms of the territory grows cereals too. We can also find orchards.

Management of soil, water, nutrients and pests
There is no irrigation in this area. Management of soils and nutrients depends of the farms, whether they are in conventional or organic farming. GAB-FRAB network is trying to promote organic methods, as organic fertilisation, mechanical weeding, rotations…

Soil improving cropping system and techniques currently used
Biological pest management, green manure, organic fertilisers

Problems that cause yield loss or increased costs
Compaction, weeds, loss of soil fertility

External drivers and factors

Institutional and political drivers
In 1964, France, with the first water law, establishes a water management by catchment areas. This water management by catchment area is then reaffirmed by the European Framework Directive on “Water 2000” which requires all its member states in order to achieve good ecological status of waters by 2015. Catchment areas are coherent territories recognized by French and European laws.

Societal drivers
The western part of France (Brittany, Pays de la Loire, Normandie) is a traditional dairy area. Large dairy companies are located in this area. Organic farming and alternative growing methods are growing much for 10 years, driven by societal demand.

Bio-physical drivers
Annual climate hazards, due to climate change, are becoming stronger. This is a major problem for the cattle management, because food autonomy is threatened. Farms have to be more resilient to climate hazards. They are developing new approaches: innovative crops, new grass management methods…

Oust-Ninian catchment areas

Geographical description

“Oust moyen” and “Ninian” catchment areas are localized at the north of Morbihan department, in the center of Brittany. They are part of the largest catchment area called “Oust”.

Oust moyen size is around 390 km2 and 27. 000 hectares of total cultivated area. It counts 370km of rivers. Ninian size is around 340 km2 and 24. 000 hectares of total cultivated area. Is counts 280 km of water.
Altitude: From 225 m to 10 m more or less
Geology: the entire Oust catchment area is impermeable rock (55% schist and 30% sandstone)

Pedo-climatic zone
Lusitanian/ Atlantic Central, Cambisol

OustMoyenNinian 
 Location of the Ninian and Oust Moyen catchment areas.

Cropping systems

Cropping intensity
Oust and Ninian catchment areas have 1159 farms and it is mainly a dairy area. There are 38 organic farms on the area. FRAB and local partners Agrobio35 and GAB56 are working on soils with 10 farms in this area (organic and conventional).

Types of crop
Wheat, maize and grassland. The territory has mainly traditional dairy systems : grassland systems and maize based systems. Most of the farms of the territory grows cereals too. We can also find orchards.

Management of soil, water, nutrients and pests
There is no irrigation in this area. Management of soils and nutrients depends of the farms, whether they are in conventional or organic farming. GAB-FRAB network is trying to promote organic methods, as organic fertilisation, mechanical weeding, rotations.

Soil improving cropping system and techniques currently used
Biological pest management, green manure, organic fertilisers.

Problems that cause yield loss or increased costs
Compaction, weeds, loss of soil fertility.

External drivers and factors

Institutional and political drivers
In 1964, France, with the first water law, establishes a water management by catchment areas. This water management by catchment area is then reaffirmed by the European Framework Directive on “Water 2000” which requires all its member states in order to achieve good ecological status of waters by 2015. Catchment areas are coherent territories recognized by French and European laws.

Societal drivers
The western part of France (Brittany, Pays de la Loire, Normandie) is a traditional dairy area. Large dairy companies are located in this area. Organic farming and alternative growing methods are growing much for 10 years, driven by societal demand.

Bio-physical drivers
Annual climate hazards, due to climate change, are becoming stronger. This is a major problem for the cattle management, because food autonomy is threatened. Farms have to be more resilient to climate hazards and they are developing new approaches: innovative crops, new grass management methods…