The karst dynamic system is an open system with its boundary being constrained by the existed karst morphs under and on the ground. The system interacts with hydrosphere and atmosphere as well as lithosphere under the dominance of the biosphere to cause cycle of matter and flow of energy and interactions among water and rock as well as air. Karst dynamics is developed with the following discovery: the living-matter acting mechanics in the interaction among water and rock as well as air, especially the reaction of water with CO₂ under the fast catalysis by carbonic anhydrase, and the improvement to the capacity of Mg content in calcite by polypeptide large biological molecule.