Nonlinear evolution of Alfvén-cyclotron and fast-magnetosonic waves accompanying ion and electron heating is investigated by means of a one-dimensional particle-in-cell simulation. The simulation is initiated with a spectrum of transverse electromagnetic waves with both left- and right-hand circular polarizations (i.e. Alfvén-cyclotron and fast-magnetosonic waves). It is shown that parametric decay processes lead to an inverse cascade of Alfvén-cyclotron waves and the generation of ion-acoustic waves by decay instability. It is found that the nonlinear decay processes accompany small perpendicular heating and parallel cooling of the protons, and a pronounced parallel heating of the electrons for a relatively low ion-to-electron mass ratio (mi/me = 16).