Sheridan was previously senior careers, education and lifelong-learning officer at the Royal Town Planning Institute and is keen to increase LI member numbers.
He said: "Engaging with a broader range of professionals is vital to the evolution of any profession. Our routes to membership are open to a broader range of landscape professionals and we have the processes in place to ensure we safeguard standards.
"A broader membership base will strengthen the voice and influence of the profession."
President-elect Noel Farrer made broadening the membership base one of his key aims when he was voted to be president after Sue Illman, earlier this year.
Sheridan said it was an exciting time to join the institute with increasing opportunities to work with universities and LI branches.
"Universities have their challenges, and these are shared by many other professions," he said.
"My initial focus will be on practical ways to support our universities, in particular with the employability of graduates. We also need to develop ways to bring more of the brightest school leavers into LI-accredited courses."
He said he found the commitment and leadership shown by members who are active in their branch groups to be inspiring and added that he wanted to support and encourage branches, help members champion the profession in the workplace and raise the confidence of members and the profession as a whole.