Biological Health Assessments of Lotic Waters by Biotic Integrity Indices and their Relations to Water Chemistry

Abstract

Biological health assessment (BHA) has developed as an imperative gauge in efficient management of freshwater resources and fish assemblages. The principal objective of this research is directed at the development and application of a new index under the umbrella of the famous index of biological integrity (IBI). Further, we intended to carry out comparative assessments of the new index with two existing indices and testified to their rational in Geum River watershed, which is the third largest river water basin in South Korea. We analyzed the biotic integrity of 149 different study sites in the streams and rivers of Geum River watershed, perusing fish assemblages and water quality data. The results revealed the newer index, i.e., multi-metric (mm) IBI 06 (mmIBI 06 metrics), as comparatively more efficient than previously used indices, i.e., mmIBI 08 and mmIBI 11. Furthermore, the linear regression and correlational analyses indicated harmonic relation of mmIBI 06 with mmIBI 08 (R2 = 0.85) and mmIBI 11 (R2 = 0.87). Nonetheless, linear regression modeling discovered a very strong positive relation between mmIBI 08 and mmIBI 11 (R2 = 0.91), thereby implying previously used indices demonstrate better approximation. In significant contrast to both old indices, the newer index exhibited improved facility to better classify the study sites between the assortments of ‘excellent to very poor’ compared to old indices elucidated one-step lower, i.e., from ‘excellent to poor’. For instance, the newer index categorized 60 sites as ‘very poor’, requiring immediate attention owing to biological degradation. Additionally, the newer index endures grander ability to indicate sites requiring immediate management or restoration attention with a plausible site classification, especially in relation to the invasive alien species (IAS). The water chemistry was mainly influenced by rampant anthropogenic actions compounded by intensive monsoon precipitation that may relinquish highly suitable grounds for invasive alien fish species. This may eventually lead to severe biological degradation and successive deterioration of habitat by the IAS. In conclusion, the newer index endures ample capacity to indicate the fish community disturbances in rivers and streams. Further, correlation, linear regression, as well as principal component analysis (PCA) analyses on biotic indices and water chemistry showed higher approximations. Therefore, our newer index would be a valuable BHA tool to classify and elucidate the streams and rivers by indicating sites necessitating preferred attention and restoration measures.

Long-Term Interannual and Seasonal Links between the Nutrient Regime, Sestonic Chlorophyll and Dominant Bluegreen Algae under the Varying Intensity of Monsoon Precipitation in a Drinking Water Reservoir

“…Each site's concluding chemical health status was calculated based on each metric's obtained score and summing up all the scores. The final scores alluded to the conclusive grouping into excellent (31)(32)(33)(34)(35), good (25)(26)(27)(28)(29), fair (19)(20)(21)(22)(23), poor (13)(14)(15)(16)(17), and very poor (07-11).…”

“…Therefore, investigating the consequences of various water chemistry pressures essentially includes trophic state assessment, physicochemical changes, and unprecedented damage to freshwater biodiversity [ 29 , 30 , 31 ]. Furthermore, deteriorating water quality could alter the typical structure and functioning of the aquatic ecosystems by directly or indirectly influencing the reservoir’s response to changing inclusive environmental conditions [ 32 , 33 ].…”

Ecological River Health Assessments Using Chemical Parameter Model and the Index of Biological Integrity Model

“…Where, C TN,TP,TN:TP,BOD,TSS,EC,CHL,DO is the measured value and C TN0,TP0,TN:TP0,BOD0,TSS0,EC0,CHL0,DO0 is the critical or standard value which was defined by the Korean Ministry of Environment. It is widely accepted that TP, TN, and TN:TP ratio are the indicators of nutrient pollution in the river system whereas BOD, TSS, and EC are the pointers of organic pollution, non-algal turbidity, and ionic pollution, respectively [7,8]. Trophic status of the waterbody can be determined by the concentration of CHL-a.…”

“…With the rapid urbanization, industrialization, and intensive agricultural farming the structure and function of the river and stream ecosystem are severely affected, which lead to the significant degradation of water quality and ecosystem integrity [3]. As a result, the river and streams ecosystem health assessment is getting more attention from scholars globally and has become a fundamental and increasingly important environmental management issue worldwide, especially in Australia [4], USA [5], Europe [6], Korea [7], and China [8].…”

Ecological Risk Assessment of Urban Streams Using Fish Biomarkers of DNA Damage and Physiological Responses

“…Previous research on aquatic ecosystem health diagnosis mainly focused on the population responses of aquatic communities such as fish, macroinvertebrate and periphyton [21][22][23][24] in relation to various chemical stressors, physical habitat disturbances because of anthropogenic activities as well as channel modifications [25][26][27][28]. Such ecosystem risk assessment approaches at the community level were widely applied to reveal the extent of disturbances in aquatic ecosystems in North America [29], Europe [30], Africa [31][32] and Asia [33][34].…”