Slow-Release Oxygen Fertilizer Improves Growth of Bald Cypress Affected by Salinity and Flooding.

The objective of this study was to evaluate the effects of “solid oxygen” on alleviating impacts of flooding and salinity on bald cypress seedlings. Seedlings were flooded in 185 × 152 × 23 cm plastic tubs. There were five levels of salinity: 0, 3, and 9 ppt (parts per thousand, sodium chloride, NaCl) and three flooding levels: 0 and 100% root submergence. Seedlings flooded with 0, 3 and 9 ppt NaCl were treated with or without oxygen fertilizer (OF). The results showed that 0%, 6.7% and 60.0% of flooded plants died with 0, 3 and 9 ppt salinity, respectively. However, the flooding and salinity stressed plants grew well with “solid oxygen” because the oxygen fertilizer alleviated oxygen deficiency to the flooded cypress seedlings. This study indicated that bald cypress seedlings could tolerate either flooding or as high as 9 ppt NaCl but could not tolerate the combined stresses of flooding and salinity.