Hydrogeochemical Features of Karst in the Western Thailand

The hydrogeochemical features of typical karst region in Western Thailand were discussed based on the high-resolution automatic hydrochemical monitor and karst spring water quality test data. The standard dissolution tablet method was employed to calculate dissolution rate of different lands and main characters and dynamic factors of Thailand karst growth were analyzed. Comparing with the typical karst spring region in the southwest China, karstic water of the Western Thailand has the features of high calcium (100-120 mg/L), high contents of bicarbonate ions (8.6-9.3 mmol/L) and high specific conductance (700-820 μs/cm); the dissolution quantity of soils in the dry season was between 28.95 mg/m²·d and 214.84 mg/m²·d; the annual dissolution quantity was twice-three times greater than that of Jinfo Mountain in Chongqing or Guangxi Mashan County peak cluster depressions, indicating that under the condition of tropical monsoon climate, the karst process in river catchment was significantly stronger than that of subtropical karst region in the southwest China.