The clearance, replanning, development or redevelopment of blighted areas shall be a public purpose and public use, for which private property may be taken or acquired. Municipal, public or private corporations may be authorized by law to undertake such clearance, replanning, development or redevelopment; and improvements made for these purposes and uses, or for any of them, may be exempted from taxation, in whole or in part, for a limited period of time during which the profits of and dividends payable by any private corporation enjoying such tax exemption shall be limited by law. The conditions of use, ownership, management and control of such improvements shall be regulated by law.