1. Encouragement of contributions of capital gain real property made for conservation purposes by Native Corporations
“(C) Qualified conservation contributions by certain Native Corporations
“(i) In general—Any qualified conservation contribution (as defined in subsection (h)(1)) which—
“(I) is made by a Native Corporation, and
“(II) is a contribution of property which was land conveyed under the Alaska Native Claims Settlement Act,
“(ii) Carryover—If the aggregate amount of contributions described in clause (i) exceeds the limitation of clause (i), such excess shall be treated (in a manner consistent with the rules of subsection (d)(2)) as a charitable contribution to which clause (i) applies in each of the 15 succeeding years in order of time.
“(iii) Definition—For purposes of clause (i), the term Native Corporation has the meaning given such term by section 3(m) of the Alaska Native Claims Settlement Act.
“(iv) Valid existing rights preserved—Nothing in this provision shall be construed to modify the existing property rights validly conveyed to Native Corporations under the Alaska Native Claims Settlement Act.”