Distribution patterns of benthic macroinvertebrate communities based on multispatial-scale environmental variables in the river systems of Republic of Korea

Abstract

2020) Distribution patterns of benthic macroinvertebrate communities based on multispatial-scale environmental variables in the river systems of Republic of Korea,

Development of a predictive model for benthic macroinvertebrates by using environmental variables for the biological assessment of Korean streams

“…Therefore, NH 3 -N, TP, and turbidity were applied as relatively relaxed criteria with increasing stream size, which prevented reference streams from being biased toward small-scale streams. BOD 5 is a consistent criterion with overall lower levels than those of other variables (Min and Kong 2020). For the stream bed substratum, some streams in the Nakdong River watershed naturally and predominantly have substrates smaller than pebbles; thus, the ratio of fine particles is higher than that in other watersheds (Jun et al 2016).…”

“…Among these criteria, the effects of NH 3 -N and TP were greatest. Hence, the overall organic pollution of streams in the Republic of Korea was low, but the trophic state was high (Min and Kong 2020).…”

“…Thus, we focused on the biological variable of benthic macroinvertebrates and established the reference condition by using five environmental variables. BOD 5 and turbidity can affect a habitat depending on the sensitivity of organisms to organic and inorganic pollution, respectively (Min and Kong 2020). TP represents the trophic state of a stream; when algae thrive in a stream bed substratum because of a high concentration of TP, the habitat of benthic macroinvertebrates is limited (Dudley et al 1986;Tonkin et al 2014).…”

“…TP represents the trophic state of a stream; when algae thrive in a stream bed substratum because of a high concentration of TP, the habitat of benthic macroinvertebrates is limited (Dudley et al 1986;Tonkin et al 2014). TN is often used with TP as a variable for nutrient concentrations, but in the Republic of Korea, the background concentration of nitrogen is relatively higher than that of TP because of the overall eutrophication of water bodies resulting from intensive land use (Min and Kong 2020). For this reason, we only used TP as a variable representing the trophic state, and we used NH 3 -N, which can be toxic to aquatic organisms (USEPA 2013b), rather than TN.…”

“…For this reason, we only used TP as a variable representing the trophic state, and we used NH 3 -N, which can be toxic to aquatic organisms (USEPA 2013b), rather than TN. The higher the proportion of fine particles, the more severe the sedimentation; the result can be considered a disturbance in the stream bed since the substratum is a direct and important habitat for benthic macroinvertebrates (Jun et al 2016;Min and Kong 2020). Coarse particles may become fine because of sedimentation, which may limit the habitat available to organisms if it is covered with fine particles (Xuehua et al 2009); thus, we used coarse particles as a variable for reference streams.…”