Low connectivity of riparian vegetation communities
There are no statistically significant trends in richness of vascular
riparian plants with downstream distance in Hjuksån with all the reaches
combined or for each process domain separately. In Bjurbäcken, there was
a significant relationship between richness and distance downstream for
all reaches combined (p= 0.003, R2= 0.43) with a slope
indicating two new species per kilometer; however, there are no
significant relationships for each process domain, separately. However,
to control for the large difference in area between the different
reaches we focus our results on species density. We found an increase in
cumulative species richness (Figure 4) but a negative relationship
between species density of vascular riparian plants with downstream
distance in Hjuksån with all the reaches combined (R2=
0.21, p = 0.0471, mean = 0.05) (Figure 4a-b); however, there are no
significant relationships in Bjurbäcken or for each process domain
separately in Hjuksån (Bjurbäcken: R2= 0.009, p =
0.694, mean = 0.06). In examining relationships of reach similarity (in
terms of riparian vegetation species composition) by distance between
reaches, a few relationships can be found. There are significant
relationships when all process domains are combined for both Hjuksån (p
= 0.003 R2 = 0.05) and Bjurbäcken (p >
0.001, R2 = 0.09) (Figure 4 c-d). There is also a
significant relationship between riparian vegetation similarity and
distance between reaches for lakes in Hjuksån (p = 0.002,
R2 = 0.176) and for rapids in Bjurbäcken (p
<0.001, R2 = 0.226) (Table 2).