Sections 6 and 7 do not apply in the case of a trust of land created by a disposition in so far as provision to the effect that they do not apply is made by the disposition.
If the disposition creating such a trust makes provision requiring any consent to be obtained to the exercise of any power conferred by section 6 or 7, the power may not be exercised without that consent.
Subsection (1) does not apply in the case of charitable, ecclesiastical or public trusts.
Subsections (1) and (2) have effect subject to any enactment which prohibits or restricts the effect of provision of the description mentioned in them.