Abstract:In order to simulate soil water regimes in the riparian zone of the Three Gorges Reservoir Area, four different kinds of water treatment were applied to study the effects of multiple water stresses on growth and physiological traits of slash pine (Pinus elliottii Engelm.) seedlings. The water treatments were normal growth water treatment (NG), mild drought stress (MD), wet soil (WS) and belowground submergence (BS). The results showed that both water treatment and time had significant (P<0.05) effects on growth, biomass accumulation, and contents of oxalate and tartarate in the roots of slash pine seedlings, but had no effect of water treatment on shoot biomass. Compared to NG, the MD, WS and BS treatments significantly reduced the seedlings′ height growth and leaf biomass accumulation, but had no significant effect on shoot growth. In addition, diameter growth was significantly decreased in MD in contrast to a significant increase in WS and BS, respectively. Furthermore, MD, WS and BS not only significantly increased content of oxalate, but also content of tartarate, respectively in taproot, lateral roots, and total roots in slash pine seedlings; the content of oxalate in taproot was however not affected by MD. When subjected to multiple water stresses, slash pine seedlings demonstrated some characteristics of acclimation although the seedlings showed susceptibility in growth and biomass accumulation. Thus, intensive water management will be necessary for maintaining adequate water regimes for healthy growth of slash pine seedlings.