![]() The common wind levels in open xerophytic forest are 3–7 of Beaufort scale, occasionally can reach 8 levels, and wind speeds above 8 levels are rare 8. Wind dispersal of diaspores occurs in all types of vegetation 3, Wind can promote lateral dispersal speed of diaspores, and diaspore dispersal time/distance can be prolonged by strong horizontal wind 2, 10. Any seed will be affected by wind 9, which may further affect seed dispersal. Seeds can be dispersed in multiple ways, and, on average, 10–30% of seeds and up to 70% of the plant species in temperate plant communities are more conductive to wind dispersal 8. Seed/diaspore dispersal can influence the spatial pattern and dynamics of a plant species at the population and metapopulation levels 1, 2, 3, 5, 5, and it is an important research topic 6, 7. The effect of maternal plants on seed dispersal regulates the distribution pattern and the species composition of the community. A plant canopy could increase seed dispersal distance, which may be due to the complicated updraft generated by canopy. When falling through a plant canopy, dispersal distance of diaspores with thorns or those without appendages was promoted at low wind speed (2 m s −1), while that of diaspores with low wing loading (0.5 mg mm −2) and terminal velocity (2.5 m s −1) was promoted by relatively high (6 m s −1) wind speed. Compared with diaspores falling through open air, the dispersal distance of diaspores falling through plant canopy was decreased or increased, depending on wind speed and diaspore traits. To determine the effect of plant canopy on seed dispersal distance, a comparison of diaspores falling through open air and through plant canopy was made in a wind tunnel using three wind speeds and diaspores with various traits. The plant canopy can intercept diaspores, but the effect of the plant canopy (the aboveground portion of a plant consisting of branches and leaves) on dispersal distance has not been explored empirically. Our results suggest that seed morphology affects the dispersal probability and postdispersal establishment, but not the dispersal distance, of aquatic plants that are dispersed by fish.Seed dispersal has received much research attention. sagittifolia displayed a 47.3% decrease and 5.1 day delay, respectively.ĥ. emersum showed a 12.6% increase in germination and a 2.1 day acceleration in germination rate, whereas seeds of S. Compared with non-ingested controls, seeds of S. Gut passage had a different effect on seed germination between plant species. Patterns of seed egestion over time did not differ between the two plant species, despite the difference in seed morphology. emersum (83.15% ± 1.8% versus 56.16% ± 2.7%, respectively), the latter had an almost twofold higher probability of surviving the passage through the digestive tract (38.58% ± 2.7% versus 20.97% ± 1.5%, respectively). sagittifolia had an approximately 1.5 times higher probability of being ingested by the carp than the hard seeds of S. We found that, although the soft seeds of S. We compared dispersal probabilities between the two plant species, in which the probability of dispersal is assumed to be a function of the probabilities of seed ingestion, egestion and germination, and the dispersal distance is assumed to be a function of seed egestion rate over time.Ĥ. To examine how seed morphology influences the probability of dispersal by the common carp ( Cyprinus carpio), we studied seed ingestion, retention time and subsequent egestion and germination of seeds of Sparganium emersum and Sagittaria sagittifolia, two aquatic plant species with similar sized but morphologically different seeds.ģ. The potential for seed dispersal by fish (ichthyochory) will vary among aquatic plants because of differences in seed size and morphology.Ģ.
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