3. Results
3.1. Temporal variations in the propagules
During the study period and considering the traps for hydrochory and for other types of dispersal, a total of 43,025 propagules belonging to 106 species were collected. In the traps for hydrochory 5,435 propagules belonging to 46 species were collected and in the traps for other types of dispersal 37,590 propagules of 66 species were captured. No differences were observed in the number of propagules collected between the dry and rainy seasons in the hydrochory traps (rainy:\(\overset{\overline{}}{x}\) = 152, S.D. = 410, dry:\(\overset{\overline{}}{\text{x\ }}\)= 57.38, S.D.= 102.83, Mann-WhitneyU = 441, p = 0.06) or in the traps for other types of dispersal (rainy \(\overset{\overline{}}{x}\) = 513.85, S.D.=990.92, dry: \(\overset{\overline{}}{x}\) = 173.39, S.D.= 324.77, Mann-WhitneyU = 1157, p = 0.44) (Fig. 2a). Regarding species richness, a higher estimated species richness was observed in the rainy season than in the dry season in the hydrochory traps (rainy: q0 = 37.82, 95% C.I.: 31.60‒44.34; dry: q0 = 10.12, 95% C.I.: 7.93‒12.31), while in the traps for other types of dispersal there is a higher species richness estimated in the dry season than in the rainy season (rainy: q0 = 17.79, 95% C.I.: 16.88‒18.72; dry: q0= 27.89, 95% C.I.: 25.33‒30.32) (Fig. 2b).
Regarding the composition, the PERMANOVA shows that in the hydrochory traps the composition is different between the dry and rainy seasons (pseudo-F= 2.55, p = 0.02). Some of the species that were only observed in the rainy season were conifers (Abies hickelli yPinus sp.), some composites (Asteraceae, Asteraceae 2 y Asteraceae 6) and a grass species (Poaceae), in the dry seasonRumex sp. was a characteristic species and species such asAlnus acuminata and Clematis dioica were observed in both seasons (Fig. 3, Appendix 1). With respect to the propagules deposited by other types of dispersion, no differences were observed in the composition between the seasons (pseudo-F= 0.75, p = 0.62) (Fig. 3).
3.2. Spatial changes of propagule communities along the river
Regarding the number of propagules, no changes were observed with the increase in the distance to the origin of the river in the traps for hydrochory, while for other types of dispersal an increase in the number of propagules deposited in the dry season was observed (Fig. 4, table 1).
Regarding to the changes in species richness, a decrease in estimated species richness was observed with increasing distance from the river origin in hydrochory traps in the rainy season but not in the dry season. While for other types of dispersal, no changes were observed in the estimated species richness with the distance to the site of origin of the river in any of the seasons (Fig. 5, table 2).
Finally, nesting values were low and turnover was high in traps for hydrochory and for other types of dispersion in both seasons. No relationships of nesting or turnover values with increasing distance to sites near the river origin were observed in any of the seasons for propagules deposited by hydrochory. For other types of dispersion, a positive relationship was observed with the turnover of species in the dry season (Fig. 6, table 3).