In a 4-to-1 vote, the Zoning Board of Appeals approved a plan to build a cellphone tower on land owned by Dennis Mahoney near Jane Lane off Route 6. The tower will be built by Industrial Tower & Wireless of Marshfield, which started the application process last spring. The 145-foot-tall tower would be located near a cranberry bog and correct a gap in cell coverage, particularly in Mattapoisett Village, according to Kevin Delaney, an Industrial Tower official. Construction should begin in late spring he said. Neighbors have 20 days from the date the board makes its written decision to file an appeal, town officials said.