TY - JOUR
T1 - An evaluation of a river health using the index of biological integrity along with relations to chemical and habitat conditions
AU - An, Kwang Guk
AU - Park, Seok Soon
AU - Shin, Joung Yi
N1 - Funding Information:
The research was supported by Korean Research Institute of Chemical Technology funded by the Ministry of Environment, Korea.
PY - 2002/11
Y1 - 2002/11
N2 - We evaluated the health condition of a temperate river during June-November 1999 through applications of the index of biological integrity (IBI) using fish assemblages and qualitative habitat evaluation index (QHEI) as well as chemical analyses. Overall IBI values ranged from 13 to 37 and averaged 23 (n = 25, standard error = 1. 16), indicating a "pooror "very poor" condition according to the criteria of modified Karr [Fisheries 6 (1981) 21]. The values of mean IBI declined at a rate of 0.22 km -1 (R2 = 0.9 1, p < 0.05) along the longitudinal distance from the headwaters to the downstream sites. Reduced IBI values at downstream sites reflected low forest cover, high population density and high nutrient enrichments. Ecotoxicity tests using the river water also showed that toxic impacts were evident in the downriver sites. These factors resulted in decreases of riffle benthic species and insectivores and increases of tolerant species, anormalies and exotic species in the river. Spatial pattern in IBI agreed with QHEI values, which showed a linear relation (R2 = 0.998, p < 0.00 1) with species richness. Field measurements of conductivity and pH, an indicators for variation of conservative ions, showed that the river water was diluted by 40% fold by summer monsoon rain and surface run-off from the watershed, resulting in a physical and chemical instability during the monsoon. For these reasons, average IBI values during the monsoon and postmonsoon decreased >20% compared to the premonsoon, indicating that IBI values were also affected by flow regime. Based on the overall physico-chemical data and IBI values, the river health is rapidly degrading due to the combined effect of chemical contaminations and habitat modifications.
AB - We evaluated the health condition of a temperate river during June-November 1999 through applications of the index of biological integrity (IBI) using fish assemblages and qualitative habitat evaluation index (QHEI) as well as chemical analyses. Overall IBI values ranged from 13 to 37 and averaged 23 (n = 25, standard error = 1. 16), indicating a "pooror "very poor" condition according to the criteria of modified Karr [Fisheries 6 (1981) 21]. The values of mean IBI declined at a rate of 0.22 km -1 (R2 = 0.9 1, p < 0.05) along the longitudinal distance from the headwaters to the downstream sites. Reduced IBI values at downstream sites reflected low forest cover, high population density and high nutrient enrichments. Ecotoxicity tests using the river water also showed that toxic impacts were evident in the downriver sites. These factors resulted in decreases of riffle benthic species and insectivores and increases of tolerant species, anormalies and exotic species in the river. Spatial pattern in IBI agreed with QHEI values, which showed a linear relation (R2 = 0.998, p < 0.00 1) with species richness. Field measurements of conductivity and pH, an indicators for variation of conservative ions, showed that the river water was diluted by 40% fold by summer monsoon rain and surface run-off from the watershed, resulting in a physical and chemical instability during the monsoon. For these reasons, average IBI values during the monsoon and postmonsoon decreased >20% compared to the premonsoon, indicating that IBI values were also affected by flow regime. Based on the overall physico-chemical data and IBI values, the river health is rapidly degrading due to the combined effect of chemical contaminations and habitat modifications.
KW - Biological integrity
KW - Habitat quality
KW - IBI
KW - QHEI
KW - Trophic structure
UR - http://www.scopus.com/inward/record.url?scp=0036830388&partnerID=8YFLogxK
U2 - 10.1016/S0160-4120(02)00066-1
DO - 10.1016/S0160-4120(02)00066-1
M3 - Article
C2 - 12437291
AN - SCOPUS:0036830388
SN - 0160-4120
VL - 28
SP - 411
EP - 420
JO - Environment International
JF - Environment International
IS - 5
ER -