International Journal of Marine Science 2016, Vol.6, No.54, 1-8
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stability and permanent mineral sedimentation processes appear to be much more important, influencing the
meiofaunal distribution and macro faunal densities in Kongsfjord (Kotwicki et al
.
, 2004; Wlodarska-Kowalczuk
and Pearson, 2004). But, it is also important that the high levels of mineral sedimentation and sediment deposition
have shown to be an acute disturbance agent causing a dramatic decrease in benthic densities and diversity. In the
present study also it is noticed that, macro benthos have higher diversity towards the outer fjord but their abundance
was lower.
During the summer investigation of 2011 in the Kongsfjord, the macrofunal abundance showed that 33.2%
families were recorded from the inner fjord whereas 66.8% from the outer fjord. From the multivariate analysis of
the seven stations, a similar trend in macrofaunal abundance was observed. From the ANOSIM results significant
differences were not observed in the distribution of macrobenthic communities among the inner and outer fjords.
The overall diversity pattern indicated an increase in faunal diversity with increasing depth but the abundance of
fauna decreased with increasing depth. The patterns of decline in species diversity across the fjord have been
observed by Kotwicki et al. (2004) and Somerfield et al. (2006). The decrease in the species richness in the inner
fjord has been reported for several benthic groups including mostly brooding species (crustaceans) and those with
dispersing larvae (polychaetes and molluscs)
(Wlodarska-Kowalczuk et al., 2012).
The reason for the decline in
faunal abundance and diversity in the Arctic fjord ecosystems are strongly influenced by glacial derived
disturbances, mainly by the outflow of melt water produced by active tidal glaciers. Tidewater glaciers are often
situated in the innermost parts of the fjords and they have a strong effect on the physical regimes of whole basins
and can impact hard and soft-bottom benthic communities. Organic matter quality can play a critical role in
determining macro faunal distribution in the fjord system. There were changes in both free living nematodes and
macro faunal assemblages with increasing distance from the larger glacier, Kongsbreen which correlate to some
extent with the organic content (C:N ratio) of the sediment (Somerfield et al., 2006). In the present study also a
decreasing pattern of macrobenthic abundance with increasing distance from glaciers was noticed. Natural factors
(depth of basins, presence of sills, variable terrestrial runoff, atmospheric forcing, seasonal phytoplankton blooms)
and anthropogenic factors (organic enrichment, fishing activities) may be leading to community changes.
The similarity in abundance of meiofauna was more conspicuous in stations 4, 5 and 7. It could be the presence of
almost similar pattern of meiobenthic distribution in these stations and it was also noticed that the three stations
were located in the outer fjord. From the cluster analysis and ANOSIM, it was clear that there were significant
differences in the distribution of meiofauna between inner and outer fjords. The average abundance of nematodes
was higher in the inner region but foraminiferal abundance was higher in the outer fjord and this difference in
distribution could be a reason for this dissimilarity. The persistence of stability of meiofaunal abundance and
diversity in the inner and outer fjord of Kongsfjord revealed that meiofauna can be less sensitive than macro fauna
(Austen et al., 1989; Warwick et al., 1990) to sediment disturbance caused by decreased sediment re-suspension
due to glacial activity. Meiofaunal distribution is influenced by the uniform granulometry, unstable sediment and
constant mineral sedimentation processes. The glacial inputs and the inflow of Atlantic water masses also
contribute to the distribution of meiofauna (Gulliksen et al., 1985; Kendall, 1994; Holte et al., 1996; Holte and
Gulliksen 1998). The present study on meiofauna corroborates with that by Kotwicki et al. (2004). Urban-Malinga
et al. (2005) also reported that nematodes, oligochaetes and turbellarians were numerically dominant among the
meio benthic taxon throughout the fjord. In the present study nematodes were the numerically abundant taxon
followed by foraminiferans. Likewise the study of Pawlowska et al. (2011) revealed that in the Adventfjord,
Spitsbergen (an arctic fjord) more than 90% of all individuals were represented by nematodes.
From the present study the following conclusions can be arrived, where the macro benthic community showed an
increase in diversity towards the outer fjord but their abundance was higher in the inner fjord. Meiofaunal
community displayed higher abundance and diversity towards the inner fjord of the Kongsfjord. Polychaetes were
the dominant macro benthic taxon whereas nematodes were the dominant meio benthic taxon during the study
period. There was no significant difference in the distribution of macro benthic communities among the inner and
