Dynamically convex and global surface of section in $L(p,p-1)$ from the viewpoint of ECH

The notion of dynamically convex has been studied since it was introduced by Hofer, Wysocki and Zehnder. In particular, they showed that there muse exist a global surface of section of disk type binding a periodic orbit for the Reeb vector field in dynamically convex $(S^3,\lambda )$ by using pseudoholomorphic curves. Recently Hryniewicz and Salomão showed the same result for $L(2,1)$ by developing the original technique and after that Schneider generalized it to $(L(p,1),{\xi }_{\mathrm{s}\mathrm{t}\mathrm{d}})$. The main purpose of this paper is to introduce an alternative approach of using Embedded contact homology. In particular, we find a global surface of section of disk type in dynamically convex $(L(p,p-1),{\xi }_{\mathrm{s}\mathrm{t}\mathrm{d}})$ and relate their periods to the first ECH spectrum.