One of the key policy instruments implemented in Europe to conserve the biodiversity on farmland are agri-environment schemes (AES). However, over the last 10 years various authors have questioned the efficacy of AES in conserving biodiversity in agricultural areas. For a successful implementation of measures with a sound ecological background, farmers’ willingness to perform these measures is inevitable to have these measures widely implemented. I have investigated from both an ecological and psychological perspective what factors are hampering the outcomes of AES in the Netherlands over the last 10 years.
I demonstrated that over the last 10 years AES in ditch banks have resulted in a minimal increase in the species richness in ditch banks. However, I found no difference in the increase between ditch banks with and without management. I could attribute this increase to an increase of species with a high nutrient demand that disperse by water. From a psychological perspective I investigated what factors underlie farmers’ willingness to perform subsidized ditch bank management and unsubsidized environmental measures. I found that for subsidized ditch bank management farmers’ attitude, that is their expectancies of the outcomes of the management is strongest associated with farmers’ intention to perform ditch bank management. Whereas for unsubsidized environmental measures I found that farmers’ perception of whether these measures are associated with their self-identity is the most important determinant of willingness to perform them.
Our results demonstrate that more elaborate measures at favourable locations in the landscape are required to improve the outcomes of ditch bank management. In order to have this implemented there are two approaches; expand current prescriptions of management in which attitude towards management would be the variable to address in interventions or campaigns to enhance willingness among farmers to continue management. Alternatively, self-identity could be addressed to motivate farmers to perform additional unsubsidized measures.