On the structure of almost Yamabe solitons

In this paper, we study structures of almost Yamabe solitons which are not necessarily gradient. First, we investigate conditions that both compact and noncompact almost Yamabe solitons become trivial solitons which means the given vector field is a Killing vector field. Second, we show that an almost Yamabe soliton whose vector field is closed admits a local warped product structure with a one-dimensional base. This result can be considered as a generalization of a result in \cite{c-s-z} and \cite{c-m-m}