  In this paper, we explain how generalized dynamical r-matrices can be
obtained by (quasi-)Poisson reduction. New examples of Poisson structures and
Poisson groupoid actions naturally appear in this setting. As an application,
we use a generalized dynamical r-matrix induced by the gauge fixing procedure
to give a new finite dimensional description of the Atiyah-Bott symplectic
structure on the moduli space of flat connections on a surface.
