Spatial impacts on zooplankton
communities
Kulkarni et al. (2019) have reported geographic distance to correlate
with zooplankton community dissimilarity on a very small geographic
scale (1.5 km). In our study, however, there was no such relation
between community composition and geographic proximity, arguing against
isolation-by-distance as a significant factor in community assembly in
our system, at least on the geographic scale we analysed
(~14.0 km). Passively dispersed organisms, as
zooplankton, are dependent on dispersal vectors (e.g., Fontaneto, 2019).
If they are wind-dependent, their dispersal effectiveness strongly
depends on the geographic scale (Horvath et al., 2016; Vanschoenwinkel
et al., 2009). They can also depend on animals, so called mobile links
(Jeltsch et al., 2013; Lundberg & Moberg, 2003) to get dispersed on a
landscape scale (Brochet et al., 2009; Frisch et al., 2007;
Moreno-Linares et al., 2016; Vanschoenwinkel et al., 2008,2009). These
mobile links often do not necessarily create an isolation-by-distance
related dispersal framework, as they may not explore habitats in a
purely distance-related manner and may have other selective criteria,
such as landscape configuration (habitat quality, connectivity,
competition etc.). In addition, these factors may change temporally,
especially in agricultural landscapes (due to farming/cultivation
activities). These complex and confounding factors may result in dynamic
and non-linear dispersal dynamics for passive disperses (like
zooplankton), which makes it difficult to detect any distance-based
patterns, should they exist on the scale of the analysed metacommunity
(Burel & Baudry, 2005; Kleyheeg et al., 2017; Kloskowski et al., 2010).
Furthermore, individual zooplankton species might have different
dispersal rates/abilities (Caceres & Soluk et al., 2002; Frisch et al.,
2007; Vanschoenwinkel et al., 2009) and pathways (Lopes et al., 2016), a
pattern potentially masked in our community approach.