(a) A municipality may not exercise any of its powers to enact ordinances within an urban agricultural area in a manner that would unreasonably restrict or regulate farming practices in contravention of the purposes of this Act unless the restrictions or regulations bear a direct relationship to public health or safety.
     (b) A unit of local government providing public services, such as sewer, water, lights, or non-farm drainage, may not impose benefit assessments or special ad valorem levies on land within an urban agricultural area on the basis of frontage, acreage, or value unless the benefit assessments or special ad valorem levies were imposed prior to the formation of the urban agricultural area or unless the service is provided to the landowner on the same basis as others having the service.