Compensatory growth of a submerged macrophyte (Vallisneria spiralis) in response to partial leaf removal: effects of sediment nutrient levels

摘要

Many plants mitigate damage due to loss of tissues through compensatory growth, yet their compensatory abilities vary depending on physical and environmental conditions. We conducted an outdoor experiment using a 2 × 2 factorial experimental design (leaf damage and nutrient level), in order to evaluate the compensatory growth response of Vallisneria spiralis (a submerged macrophyte widely distributed in China) to partial leaf removal in two nutrient regimes. Our results reveal that under both high- and low-nutrient conditions, V. spiralis exhibited substantial compensatory growth response to partial leaf removal via accelerated growth rates, with significantly greater compensatory abilities observed in the high-nutrient sediments. These observations suggest that V. spiralis has a strong compensatory ability to partial leaf removal, providing arguably one of the major mechanisms for the coexistence of this plant with herbivores, in particular, in eutrophic freshwater ecosystems (e.g. Lake Taihu).