For purposes of this chapter: the term "affected community board" shall mean the community board for a community district in which land included in a plan or an application pursuant to this chapter is located; the term "affected borough president" shall mean the president of a borough in which land included in such a plan or an application is located; and a borough board shall be deemed "affected" if such a plan or application includes land within two or more community districts within the borough represented by such borough board.