## 4 Discussion  
### Salt Marsh Monitoring and Characterization  
In the study of the three different transects, we found that the selected salt marshes shared a core set of flora comprised _S. perennis_, _A. portulacoides_, _J. maritimus_, and _S. maritimus_ (Figures 2-4). The observed communities were consonant with the halophytic-rich ones commonly found at temperate latitudes, where there is usually a prominent dominance of herbaceous species [1; 47; 48], and although less common in northern salt marshes, the dominance of sub-shrubby species such as _A. portulacoides_ and _S. perennis_ is also in agreement with earlier findings at the lower limit of the temperate floristic cluster where our study area is situated [1; 48]. Overall, the floristic communities at the study sites evidenced very few changes over the year, and the changes that occurred were related either to the emergence and subsequent disappearance of annual species or coverage adjustments seemingly related to flowering periods of certain species. Notice that higher cover-abundance values of the main species overlapped with their respective flowering period, ranging from August to November for _A. portulacoides_ and _S. perennis_, July to September for _S. maritimus_, and May to July for _J. maritimus_, as shown in Figures 13-14. Likewise, when set against previous data collected from salt marshes at Mira's channel (December 1995 to December 1996) [49] and with other unpublished data (May 2010 and January 2011) collected by us, our results showed that although this region has been subjected to degradation, changes in vegetation cover, and loss of area [33], there has been only some slight changes in its communities composition over the past two decades. Overall, the main differences between the four sampled periods illustrated the disappearance of _S. europaea_ beyond the years sampled by [PERSON] [49] (though understandably so given this species' pioneer status and annual character) and the observed emergence of _S. versicolor_ in 2010 and _E. repens_ and _C. edulis_ in 2021. Moreover, just like in this investigation, _S. perennis_, \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multicolumn{7}{c}{**PERMANOVA Table of Results**} \\ \hline
**Source** & **df** & **SS** & **MS** & **Pseudo-F** & **P (Perm)** & **Unique Perms** \\ \hline Sp & 2 & 990.13 & 495.06 & 169.34 & 0.001 * & 998 \\ \hline Sa & 2 & 476.63 & 238.31 & 81.515 & 0.001 * & 999 \\ \hline Mo & 9 & 232.15 & 25.795 & 8.8231 & 0.001 * & 997 \\ \hline SpxSa ** & 3 & 214.84 & 71.615 & 24.496 & 0.001 * & 999 \\ \hline SpxMo & 18 & 61.64 & 3.4244 & 1.1713 & 0.106 & 998 \\ \hline SaxMo & 18 & 177.01 & 9.8337 & 3.3636 & 0.001 * & 996 \\ \hline SpxSaXMo ** & 27 & 89.979 & 3.3326 & 1.1399 & 0.103 & 993 \\ \hline Res & 320 & 935.54 & 2.9236 & & & \\ \hline Total & 399 & 3192 & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Permutational multivariate analysis of variance (PERMANOVA) of monthly (Mo) changes in physicochemical and hydrodynamic variables under patches belonging to the most dominant observed species (Sp) at the different studied salt marshes (Sa). A. portulacoides, J. maritimus, and S. maritimus were the most abundant species (although not always following the same proportions). We also found that communities were more even, diverse, and less dominated by a particular species at the intermediate levels of altitude of each salt marsh (Figure 5), where intermediate values of inundation periods and frequency, as well as water depth, were typically found, possibly because these latter hydrodynamic parameters could have ultimately acted as disruptive forces--since they are usually associated with salinity and oxidative stresses and the deposition of potentially damaging debris [1; 50]--especially in lower elevations where they were more prominent (as illustrated by Figures 6 and A4-A6), but any further considerations about this possibility should ideally be investigated in the future within more sampling sites.