With the exception of "Mississippi Landmarks," as defined by the Antiquities Law of Mississippi (Section 39-7-1 et seq., Mississippi Code of 1972) and of properties entered in the National Register of Historic Places, no public money, derived either from a special fund or the General Fund, shall be expended for capital improvements on any real property upon which a conservation easement has been granted unless the conservation easement is perpetual, a governmental body is the holder of the easement and the capital improvements are solely for the use and benefit of such holder.