Effects of sediment burial disturbance on seedling survival and growth of Suaeda salsa in the tidal wetland of the Yellow River estuary

Abstract

A greenhouse experiment was conducted to determine the effects of sediment burial on survival, growth and dry mass allocation of seedlings of Suaeda salsa (L.) Pall. (Chenopodiaceae), an important pioneer species of tidal wetland near the Yellow River estuary. From April to June 2009, seeds were buried at 0.5 cm depth in plastic pots filled with sediment. Two weeks after emergence, seedlings were buried to depths of 0 (H0), 33% (H33), 67% (H67), 100% (H100) and 133% (H133) of their mean height. Results showed that seedling survivorship, height, absolute height growth rate, relative height growth rate, stem diameter, number and length of branches, dry mass and relative growth rate were significantly affected by burial depth (P< 0.01). Although dry mass allocations changed with increasing burial depth, allocations to root, stem and leaf were not significantly affected by burial depth (P> 0.05). No seedlings died in the partial burial treatment, approximately 18.06±5.32% seedlings survived when they were completely buried, and no seedling survived when the burial depth reached 133% of the seedling height. Seedling height, absolute height growth rate, relative height growth rate, stem diameter, number and length of branch, dry mass and relative growth rate in the partial burial treatments were much higher than those of the unburied and completely buried treatments. With increasing burial depth, there was a tendency that both allocation to root and allocation to leaf increased, while allocation to stem decreased. The stem of S. salsa formed adventitious roots after being buried for less than 4 weeks, which was favorable for the survival and growth of seedlings, reflecting the fact that the S. salsa seedlings indeed exhibit a special adaptive strategy against rapid sediment burial in tidal wetland. The burial experiment also indicated that moderate burial disturbance (H33 and H67) increased seedling vigor, while strong burial disturbance (H100) Plant Soil (2010) reduced seedling vigor. The use of thin-layer sediment burial to promote the vigor of plants in degraded wetland is very feasible, and our results provide valuable practical information applicable to the restoration of degraded S. salsa wetland.

Seed Burial Depth and Soil Water Content Affect Seedling Emergence and Growth of Ulmus pumila var. sabulosa in the Horqin Sandy Land

“…However, when the soil water contents was from 8% to 16%, seedling height was greater at 0.5 and 1.0 cm of sand burial depths than at 1.5 and 2.0 cm seed burial depths. A similar growth stimulation at lower seed burial depths was reported on Suaeda salsa and Triplasispurpurea [39,40]. Sun et al [40] showed that moisture could be kept in the root zone at smaller rather than greater seed burial depths to improve seedling growth and development.…”

“…Sun et al [40] showed that moisture could be kept in the root zone at smaller rather than greater seed burial depths to improve seedling growth and development. These positive feedback effects would recede when plant tolerance levels are exceeded, thus constraining the subsequent plant growth [39].…”

Sand burial compensates for the negative effects of erosion on the dune-building shrub Artemisia wudanica

“…Similarly, studies conducted with other dune species have shown that the growth stimulation of partially buried seedlings were caused primarily by an increase in the production of adventitious roots (Dech and Maun 2006;Liu et al 2008;Sun et al 2010). The reasons for producing adventitious roots when buried are not well understood.…”

“…Previous observations have shown that A. wudanica bends over by wind erosion and then accumulates blown sand among its fallen stems, forming a sand-protecting barrier (Jin and Ye 1989). The deposition of sand will enable the formation 4 of adventitious roots from stems' nodes, contributing to the colonization and clonal expansion of this species Liu et al 2008;Samsone et al 2009;Sun et al 2010). The formation of these roots will favor the acquisition of more nutrients from the sediment, stimulating aboveground growth (Liu et al 2008).…”

Experimental sand burial affects seedling survivorship, morphological traits, and biomass allocation of &lt;i&gt;Ulmus pumila&lt;/i&gt; var. &lt;i&gt;sabulosa&lt;/i&gt; in the Horqin Sandy Land, China

“…This indicated the maintenance of leaf area for photosynthesis and evapotranspiration were important for sandy elm seedlings exposed to high temperature and irradiance in the growing season (Dulamsuren et al, 2009;Li et al, 2003;Park et al, 2012). The relative investment in root was slightly decreased, which indicated, on the one hand, that greater soil moisture availability weakened the dependence on root function and, on the other hand, the plant's need to divert biomass aboveground for light interception and net assimilation rate (Maun, 1994;Sun et al, 2010;Wang et al, 2014).…”