In the last few decades, nutrient-rich wastewater has become a worldwide problem due to exponentially increased anthropogenic activities causing eutrophication or algal blooms in waters and affect the water bodies with their biological and chemical activities. Physico-chemical techniques have shown promising results, while operational cost, hefty sludge generation, and energy requirement are the major drawbacks. On the other hand, biological processes are cost-effective and efficient, although

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... hey are associated with design complexity and extensive monitoring. Among biological techniques, constructed wetland (CW) is an economical, efficient, and green technique for nutrient removal comprising of inherent mechanisms, such as microbial degradation, rhizofiltration, phytodegradation, sorption, etc. This major highlight of the present study is to apprise and critically analyze the ideal conditions and system insights to enhance the nutrient removal efficiency of CW. Macrophytes play a vital role in CW and its planting practices, namely monoculture and polyculture, also influence the removal efficiency of the CW. In the present study, an in-depth analysis reflected that polyculture exhibits better treatment for TN and TP compared to monoculture practices. The observed optimum conditions for nutrient removal in CW were polyculture in combination with higher temperature (23ºC-29ºC), artificial aeration, advanced substrate, and bioaugmentation. The review emphasized the process and design criticality of CWs in removing nutrients from various types of wastewater, which may be instrumental for water research and field applications.