Complex sentence: It is an "ad valorem" tax on land that disregards the value of buildings, personal property and other improvements but not the value due to the land's location, such as proximity to a major highway or shopping complex.
Split into simpler sentences: It is an "ad valorem" tax on land that disregards the value of buildings, personal property and other improvements. A land tax, however, does not disregard the value of property due to it's location, such as convenience to a major highway or shopping complex.