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Master Thesis

Éléments pour une analyse de l’efficacité des mesures de lutte contre les algues vertes en Bretagne

Abstract : The proliferation of green algae in Brittany is an indicator of the degradation of water quality by excess nitrates mainly due to nitrogen leakage from agricultural systems. This phenomenon has been the subject of several programs to reduce the level of nitrogen in Brittany's waters. Various measures have thus been undertaken by the eight bays concerned by the Green Algae Plan (Bay of Saint-Brieuc, Le Lieue de Grève, Concarneau, Horn-Guillec, Douarnenez, Fresnaye, Locquirec and Guissey). They have certainly reduced nitrogen runoff, but algal blooms are still present. The aim of the study is to see the economic and social factors that influence or hinder farmers' commitment. To carry out this work, a synthesis of water governance, the implementation of plans and the indicators used for their monitoring was carried out. A series of interviews with bay technicians was conducted to compare the hypotheses developed from the synthesis work. Several proposals emerged for a more systemic approach to the challenges of mobilizing public policy instruments, including the question of economic information, the commitment of the sectors, a more integrated approach to evaluation highlighting the cause-effect relationships from the determinants to the effects of the actions undertaken.
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Master Thesis
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Contributor : Agrocampus Ouest <>
Submitted on : Tuesday, November 17, 2020 - 9:19:12 AM
Last modification on : Friday, January 29, 2021 - 12:47:48 PM
Long-term archiving on: : Thursday, February 18, 2021 - 6:24:25 PM


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  • HAL Id : dumas-03008928, version 1


Moussa Diaw. Éléments pour une analyse de l’efficacité des mesures de lutte contre les algues vertes en Bretagne. Sciences du Vivant [q-bio]. 2020. ⟨dumas-03008928⟩



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