Laws may be enacted to provide for the establishment and creation of special districts to provide emergency services and to authorize the commissioners courts of participating counties to levy a tax on the ad valorem property situated in said districts not to exceed Ten Cents (10¢) on the One Hundred Dollars ($100.00) valuation for the support thereof; provided that no tax shall be levied in support of said districts until approved by a vote of the qualified voters residing therein. Such a district may provide emergency medical services, emergency ambulance services, rural fire prevention and control services, or other emergency services authorized by the Legislature.