Effects of mechanical damage on leaf veins of nine aquatic plants

Aquatic plants are important primary producers in the littoral zone of lakes and wetlands. As aquatic plants have a close relationship with the aquatic environment, their leaves usually do not need to adapt to water shortages in the soil. Therefore, the leaf traits of aquatic plants are likely to be different from those of terrestrial plants. In addition, leaf vein type is the fundamental basis of leaf functional traits; however, previous studies on leaf vein types and functional traits have not yet been conducted for aquatic plants. In this study, nine aquatic plants with different vein type were selected to analyze the relationship between the changes in leaf traits (e.g., morphology, pigment content, and chlorophyll fluorescence) and vein type after vein cutting. Results showed that the three species with parallel veins exhibited strong tolerance to the main vein cut, whereas the four species with pinnate veins demonstrated significantly reduced pigment content and inhibited leaf growth following the main vein cut. In contrast, the side vein cuts had distinct effects on different species, indicating species-specific effects. Based on leaf vein type, this study provides theoretical guidance for species selection in the re-establishment of aquatic plants in the littoral zone of large lakes.