Enhancing River Health through an Integrated ISC Assessment Methodology Enhancing river health through ISC assessments: a holistic method

Abstract

Researchers commonly used the Index of Stream Condition (ISC) to assess the ecological state of river basins and rivers. However, the interdependence of factors across multiple hierarchical levels can rapidly influence the outcomes of ecological assessments. This study presents an integrated method that significantly enhances the river's health. Our holistic method addresses the issue of improving ecological assessments. Moreover, we performed dimensions' reduction, inconsistency testing, and clustering within and between ISC3 sub-indexes and metrics for logical assessment and factor classification. The results show that the ISC3 sub-indexes can be reduced from five to three, achieving a 40% reduction in dimensionality. At the same time, the ISC3 metrics can be decreased from twenty-three to twelve, resulting in a 47.83% dimensionality reduction compared with the status quo. The discriminant coefficient (R-2) significantly increased from 67.78 to 88.15%, a substantial improvement that reassures the effectiveness of our method. Moreover, all inconsistency index (InC.I.) values within and between ISC3's sub-indexes and metrics were below the critical value of 0.1, indicating high cluster homogeneity. These findings indicate that reducing the number of ISC3 index/sub-index factors and ensuring their homogeneity enhances their clustering effect. The proposed method will help future ecological inspections, assessments, and river health management, offering hope for significant improvements in these areas. Highlights circle This study introduces a novel integrated methodology, a significant leap in the field, to enhance the ecological assessment of river basins using the Index of Stream Condition (ISC). circle The application of the Analytical Network Process (ANP) and Principal Component Analysis (PCA) has proven superior to traditional factor clustering methods, ensuring more accurate and reliable evaluations of river health. circle The authors address the interdependencies among factors across multiple hierarchical levels, a vital component often overlooked in traditional assessments. circle Our rigorous analysis achieved a 40% reduction in the ISC3 sub-indexes, decreasing from five to three. This reduction signifies a more streamlined and efficient assessment process. We also achieved a remarkable 47.83% reduction in the number of metrics, from twenty-three to twelve. This reduction in the number of metrics indicates a more focused and precise evaluation of river health. circle The discriminant coefficient (R2) improved significantly from 67.78% to 88.15%, a substantial leap that provides strong validation for the effectiveness of our approach. All inconsistency index (InC.I.) values were below the critical threshold of 0.1, demonstrating high cluster homogeneity and enhancing clustering effectiveness. circle Our findings offer promising advancements for future ecological inspections, assessments, and river health management, instilling hope for substantial improvements in environmental sustainability.