Polychaete Community Structure from Inshore and Offshore of Lake Shihwa (Korea) in March, 2008

Abstract

Polychaete community structure and its spatial distribution was investigated in 2008 from inshore and offshore of Lake Shihwa, Korea, in order to evaluate status of the benthic environment according to construction of the dike and the water gate. In the present study, the number of species, density, and diversity of polychaete community in inshore was significantly different from those in offshore. The density of polychaete community in offshore increased with the number of species whereas the diversity in inshore increased with the number of species. Dominant species in offshore were 13 species, higher than 1% of the total polychaete individuals. Heteromastus filiformis, known as the most dominant species before the construction of the dike, was the most dominant species in offshore, which collectively account for 54% of the total polychaete individuals. In inshore, the seven species were dominant, higher than 1% of the total individuals. Lumbrineris longifolia, Polydora sp., Capitella capitata, Pseudopolydora paucibranchiata, known as pollution tolerant species, contributed to higher than 75% of the total individuals in inshore. Multivariate statistical analyses, non-metric multidimensional scaling, showed apparent difference in polychaete community structure between inshore and offshore, and also difference between inner sites and outer sites of inshore around the water gate. Sediment characteristics (total organic carbon and nitrogen, ignition loss, and acid volatile sulfide) measured in this study also supported to this result. Therefore, this indicates that the offshore provides better benthic environments for polychaete habitation than the inshore, and the inshore around the water gate shows improving benthic environment, compared to the inner inshore.

Hypoxia in Korean Coastal Waters: A Case Study of the Natural Jinhae Bay and Artificial Shihwa Bay

“…Benthic communities in SB have been altered significantly by multiple factors (i.e., development of bottom-water as well as changes in circulation, salinity, eutrophication, and isolation) (Figure 9) (Hwang, 2008;Jung et al, 2012;Lee et al, 2014). Lee et al (2003) investigated the total numbers of benthic faunal species in SB in three periods: before the dyke was built (1980), the early desalination period (1994)(1995), and the late desalination period (1995)(1996).…”

“…These results indicate that the SB benthic community has recovered partially since 1997. However, the bottom-water hypoxia occurring in summer due to insufficient water exchange and the input of large amounts of pollutants from inland still impacts the benthic community in SB (Hwang, 2008;Jung et al, 2012). For example, decreases in the number of species, abundance, and diversity of benthic fauna were observed in June and September in the inner area ( Figures 9E-G).…”

First record of Heteromastus filiformis (Polychaeta: Capitellidae) from Korean waters, with a taxonomic note on the genus

“…Besides to these, two capitellid species, Heteromastus filiformis (Claparède, 1864) and Mediomastus californiensis Hartman, 1944, have been reported as one of the members of benthic macroinvertebrate community through many ecological studies without any taxonomical consideration (Hong et al, 2000;Choi et al, 2003;Shin et al, 2004;Seo et al, 2009;Jung et al, 2014, etc.). Although Heteromastus filiformis is one of the capitellid species that has been most frequently reported from Korean waters by such ecological studies (Jung et al, 1997;2012;Hong et al, 2000;Choi et al, 2003;Shin et al, 2004, etc. ), its taxo nomical reality has not yet been examined in Korean wa ters.…”