Long- and short-term flooding effects on survival and sink-source relationships of swamp-adapted tree species

Abstract

About 95% of swamp tupelo (Nyssa sylvatica var. biflora (Walt.) Sarg.) and sweetgum (Liquidambar styraciflua L.) seedlings survived continuous root flooding for more than two years, whereas none of the swamp chestnut oak (Quercus michauxii Nutt.) and cherrybark oak (Q. falcata var. pagodifolia Ell.) seedlings survived one year of flooding. Death of oak seedlings occurred in phases associated with periods of major vegetative growth, e.g., after bud burst in spring, after summer stem elongation, and during the winter deciduous stage, suggesting that stored reserves and sources were inadequate to maintain the seedlings when vegetative sinks were forming. Additional evidence that flooding induced a source deficiency in oak was that leaves of flooded oak were 65 to 75% smaller than leaves of nonflooded oak. Flooded swamp tupelo seedlings had a normal leaf size and patchy stomatal opening compared with nonflooded seedlings. Flooding caused increases in alcohol dehydrogenase (ADH) specific activity in taproot cambial tissues and increases in starch concentrations of swamp tupelo seedlings that were reversed when seedlings were removed from flooding. Flooding had little effect on soluble sugar concentrations in swamp tupelo or sweetgum. In the long-term flood-dry-flood treatment, in which all species had survivors, upper canopy leaf photosynthetic rates were higher in all species during the dry period than in nonflooded controls, whereas their starch and soluble sugars concentrations were similar to those of nonflooded controls. Based on seedling survival and the sink-source relationships, the order of flood tolerance was: swamp tupelo > sweetgum > swamp chestnut oak > cherrybark oak.

Do greenhouse experiments predict willow responses tolong term flooding events in the field?

“…In addition to that, stomatal conductance was reduced in flooded plants of 13-44 (figure 6). These results are consistent with previous findings that flood tolerant species maintain a higher growth (Angelov et al 1996) and a higher stomatal conductance than those kept by flood sensitive species (Pezeshki 1993, Sun et al 1995. From these results, 13-44 can be defined as flood sensitive, while all the other clones are tolerant to relatively short-term flooding.…”

“…Survival after a long period of flooding is species-dependent (Terazawa and Kikuzawa 1994, Angelov et al 1996, Amlin and Rood 2001, Parelle et al 2007. Swamp-adapted tree species can survive up to two years of continuous root flooding (Angelov et al 1996), and some trees which grow in seasonally flooded areas such as the Amazonas floodplain are adapted to complete submergence for a long period of time (Parolin 2009).…”

“…Survival after a long period of flooding is species-dependent (Terazawa and Kikuzawa 1994, Angelov et al 1996, Amlin and Rood 2001, Parelle et al 2007. Swamp-adapted tree species can survive up to two years of continuous root flooding (Angelov et al 1996), and some trees which grow in seasonally flooded areas such as the Amazonas floodplain are adapted to complete submergence for a long period of time (Parolin 2009). Central European Salix species have been reported as having high tolerance to flooding episodes in the field (Glenz et al 2006); and in a pond originated from a beaver dam in Montana, they were still alive after 5 years of flooding (Amlin and Rood 2001).…”

Differential Response of Gray Poplar Leaves and Roots Underpins Stress Adaptation during Hypoxia

“…As suggested from accelerated Suc and starch catabolism, Glc, Fru, and Fru-6-P concentrations increased in roots, while starch concentration showed a slight, but not significant, decrease after 1 week of hypoxia. Increased carbohydrate levels in the roots of flooded plants have been previously observed in trees and herbaceous species (Albrecht et al, 1993;Castonguay et al, 1993;Huang and Johnson, 1995) and have been explained by a reduced carbon demand due to a decline in root growth and nitrogen metabolism (Angelov et al, 1996). In contrast, the results of this study suggest that improved sugar supply to hypoxic roots occurs in order to compensate for increased carbohydrate demand under these conditions.…”

Height-diameter Relationships in Longleaf Pine and Four Swamp Tree Species

“…Otherwise, the tree would be expected to die from suffocation, since water-saturated soils contain less oxygen than well-aerated, better-drained soils. But, there is little actual evidence for this assertion (Angelov et al, 1996). Metabolic ecology postulates a power law with an invariant exponent, because all tree species share an optimal design for their vascular system, which is related to plant physiology West et al, 1999).…”