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Wetlands are a ubiquitous ecosystem, found in all regions and climatic conditions across the globe. But they have long been a misunderstood ecosystem due to the misconception that they are “wastelands, disease‐infested, dark and dirty swamps,” and therefore, considered worthless and large numbers of them have been converted for the other land‐use activities (Shah 2012). Later, the advancement of wetland research made the importance of these ecosystems clear, as they interlink land and aquatic ecosystems, and therefore, understanding developed from the conversion to the conservation of wetlands (Shah 2012). They are considered as the “transitional zone between terrestrial and aquatic ecosystems,” where the water table is usually at or near the surface or the land is covered by shallow water (Mitsch and Gosselink 1986). These are the most productive and biologically diverse ecosystems, but they are also very fragile in nature (Mitsch and Gosselink 2000). They were defined for the first time during the world convention on wetlands at Ramsar city, Iran, on 2 February 1971 as:

Wetlands are area[s] of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water, the depth of which at low tide does not exceed six meters.

The wetlands contribute approximately 40–45% of the total global estimate of natural productivity and ecosystem services, as reported in the various wetland ecosystem assessment reports.