Ecological health assessments using multiple parameters of fish blood tissues to community along with water chemistry in urban streams

Abstract

The objectives of this study were to identify multi-level stressors from blood biomarkers to community-level bioindicators and diagnose the stream ecosystem health in polluted streams. Blood chemistry such as total protein (TPro), blood urea nitrogen (BUN), total cholesterol (TCho) and albumin (Alb) were analyzed from sentinel fish tissues; the functions of kidney, gill and liver were significantly decreased in the impacted zone (I z), compared to the control zone (Cz). Histopathological analysis showed that fish liver tissues were normal in the C z. Fish liver tissues in the Iz, however, showed large cell necrosis and degeneration and also had moderate lobular inflammation and inflammatory cell infiltration of lymphocytic histocytes. Species biotic index (SBI) at species level and stream health assessment (SHA) at community level indicated that chemical impacts were evident in the Iz (ecological health; poor - very poor), and this was matched with the blood tissue analysis and histopathological analysis. The impairments of the streams were supported by water chemistry analysis (nitrogen, phosphorus). Tolerance guild analysis and trophic guild analysis of fish were showed sig nificant differences ( P < 0.01) between Cz and Iz. Overall, multiple parameter analysis from biomarker level (blood tissues) to bioindicator level (community health) showed significantly greater impacts in the I z than Cz. This approach may be effective as a monitoring tool in identifying the multilateral and forthcoming problems related to chemical pollution and habitat degradation of stream ecosystems.