Nature preserves dedicated under § 7306 of this title are to be held in trust, for the uses and purposes set forth for the benefit of the people of the State of present and future generations. They shall be managed and protected in the manner approved by, and subject to, the rules and regulations established by the Department. They shall not be taken for any other use except another public use after a finding by the Department of the existence of an imperative and unavoidable public necessity for such other public use and with the approval of the Governor after consultation with the Advisory Council, and by act of the General Assembly not less than 6 months from the date of the Governor's approval. Except as may otherwise be provided by the articles of dedication, the Department may grant, upon such terms and conditions as it may determine, an estate, interest or right in, or dispose of, a nature preserve, but only after a finding by the Department of the existence of an imperative and unavoidable public necessity for such grant of disposition, and with the approval of the Governor after consultation with the Advisory Council, and by act of the General Assembly not less than 6 months from the date of the Governor's approval.