(1)Seats shall be reserved for-(a)the Scheduled Castes ; and(b)the Scheduled Tribes -in every Zilla Parishad and the number of seats so reserved shall bear, as nearly as may be, the same proportion to the total number of seats to be filled by direct election in the Zilla Parishad as the population of the Scheduled Castes in that Zilla Parishad area or of the Scheduled Tribes in that Zilla Parishad area, as the case may be, bears to the total population of that area and such seats may be alloted by rotation to different constituencies in the Zilla Parishad in such manner as may be prescribed.