EFFECT OF HCO3- IN IRRIGATION WATER ON THE ABSORPTION AND DISTRIBUTION OF SOIL AVAILABLE NUTRIENTS OF BEAN

Pot culture and water culture trails were used to study the effect of HCO3- in irrigation water arid different HCO3- level on the growth and ability of absorbing and using soil available nutrients of bean (phaseolus vulgaris L.). The irrigation water used in pot trails was the underground water in Beijing, in which the HCO3- level is account 8. 45mol/L. The results showed that under calcareous soil condltions, irrigating with underground water containing higher HCO3- level (8. 45mol/L) decreased the growth and total nutrient absorption, the percentage of different nutriens ranged from more than 50% to 30%, and inhabited the transportation of absorbed nutrient from stem to leaves and pods seriously: 0,5,10, 15 and 20mmol/L HCO3- level in nutrient solution of water culture were adjusted with 0. 01mol/L NaHCO3 and 5 and 10mmol/L Ca2+ level with 0.01 mol/L CaCl3, biological yield in water culture decreased with the increase. of HCO3- level, while Ca2+ colild alleviate the adverse effect of HCO3- to some extent.