The Journal of
the Korean Society on Water Environment

The Journal of
the Korean Society on Water Environment

Bimonthly
  • ISSN : 2289-0971 (Print)
  • ISSN : 2289-098X (Online)
  • KCI Accredited Journal

Editorial Office

Title Comparison of Settleable and Non-settleable Suspended Sediment in Streams and Lakes
Authors 엄재성 ( Jae Sung Eum ) ; 장성민 ( Sung Min Jung ) ; 최영순 ( Yong Soon Choi ) ; 이형진 ( Hyung Jin Lee ) ; 최중대 ( Joong Dae Choi ) ; 김범철 ( Bom Chul Kim )
Page pp.232-237
ISSN 2289-0971
Keywords Nonsettleable suspended sediment; Settleable suspended sediment; Total suspended solids; Turbidity
Abstract Total suspended solids (TSS), settleable suspended solids (SSS) and nonsettleable suspended solids (NSSS) were compared in streams and lakes during rain events. Samples were collected in Lake Soyang and nine agricultural streams during storm events over two years. To measure NSSS, samples were settled in 1 L cylinders for one hour and then 50% of the total sample volume was taken from the center of the cylinder. The SSS/TSS ratio in streams (0.50) was higher than in Lake Soyang (0.20). The ratio of TSS to turbidity decreased from 1.21 in the inflowing river to 0.69 in the reservoir outlet. Turbidity and NSSS showed higher correlation (r2=0.82) compared with the correlation between turbidity and TSS (r2=0.66). Median particle size decreased from 11.4 μm in the inflowing river to 4.2 μm in the lake outlet. The results indicate that only fine particles of less than 5~10 μm can be transported downstream of the lake. Because fast-flowing water in streams includes not only fine particles but also coarse particles, an overestimation of suspended sediment concentration results if only TSS is measured. Consequently, TSS and NSSS should be measured separately to evaluate the effect of suspend sediment loadings of turbid streams on aquatic habitat during the monsoon season.