Unraveling eutrophication controversies: Innovative strategies and holistic perspectives

Eutrophication remains a persistent global water quality challenge despite extensive investigations. Numerous reviews highlight multifaceted controversies, and scholars from diverse fields have attempted reconciliation, yet pessimism prevails. The authors perform a detailed exploration of the current controversies and debates surrounding eutrophication strategies. After leveraging a combination of historical data review, theoretical insights, and advanced modeling, we identify common roots of these controversies, primarily improper problem framing or boundary setting caused by conceptual weaknesses, methodological omissions and residual variability when dealing with complex nexuses, which can lead to multifinality, equifinality, or insoluble problems in subsequent research, fostering redundant and intense debates. Therefore, more efficient techniques during problem framing or conceptual model construction, fully should be emphasized, balancing realism and practicability. Instead of seeking a panacea for eutrophication restoration, we propose an Improved Analytic Hierarchy Process (IAHP) method and an Iteratively Evolutionary Modeling Cycle Method, based on newly proposed sets of criteria. The IAHP method combines traditional Analytic Hierarchy Process with multivariate statistics, breaking down complex problems into a hierarchical structure and determining factor weights through pairwise comparisons or multivariable statistics. The Iteratively Evolutionary Modeling Cycle Method tackles complex modeling by segregating processes into six iterative steps, ensuring expertise-specific problem-solving while fostering communication and collaboration across steps. Both approaches emphasize segmented, iterative optimization, avoiding equifinality and multifinality problems, reconciling conflicts among diverse dimensions and aligning with the principles of Occam's Razor. These methods offer valuable approaches to addressing conflicts arising from multifactorial issues.