1. Karst landforms and landscapes form in association with groundwater and include features such as caves and sinkholes. Caves begin to form during a period of high water table when flowing groundwater dissolves carbonate-rich limestones through the process of carbonation. Caves become open when the water table falls, usually in association with stream downcutting or, perhaps, climate change. Class, How does the formation of a sinkhole relate to the process of land subsidence and the formation of tower karst?