Dataset of Rapid adaptive responses of rosette-type macrophyte Vallisneria natans juveniles to varying water depths: The role of leaf trait plasticity

Rosette-type submerged macrophytes are widely distributed across a range
of water depths in shallow lakes and play a key role in maintaining
ecosystem structures and functions. However, little is known about the
rapid adaptive responses of such macrophytes to variations in water depth,
especially at the juvenile stage. Here, we conducted a short term in situ
mesocosm experiment, in which the juveniles of Vallisneria natans were
exposed to a water depth gradient ranging from 20 to 360 cm. Twenty-two
leaf-related traits were examined after four weeks of growth in a shallow
lake. Most (18) traits of V. natans generally showed high plasticity in
relation to water depth. Specifically, juveniles allocated more biomass to
leaves, and had higher specific leaf area, leaf length to width ratio,
chlorophyll content, and carotenoids content in deep waters, displaying
trait syndrome associated with high resource acquisition. In contrast, V.
natans juveniles in shallow waters had higher leaf dry matter content,
leaf soluble carbohydrate content, carotenoids per unit chlorophyll, and
peroxidase activity, pertaining to resource conservation. Notably,
underwater light intensity was found to be the key factor explaining the
trait plasticity along the water depth gradient, and 1.30 mol photons m–2
d–1 (at 270 cm) could be the optimal irradience level based on the total
biomass of V. natans juveniles. The present study highlights the
significance of leaf trait plasticity for rosette-type macrophytes in
response to variations in water depth, and sheds new light on the
differences between trade-offs in deep- and shallow-water areas.