A Review of Ecosystem Services Approach With Particular Reference To Wetland Ecosystem Services

Humans have remained highly dependent on the availability of ecosystem services (ES). Over the past 300 years (more intensely in the past seven decades), human activities have degraded the ecosystems and lowered the availability of ES. This has resulted in foregone benefits of well- functioning of ecosystems and ES. Having recognized the multi-dimensional aspects of values of ES, the current research trajectory is inclined towards institutionalizing the science of valuing nature’s contributions that have aimed to spearhead discussions with the transdisciplinary academic community.This paper explores the studies conducted on the overarching theme of ‘ES valuation’. Primarily, the study reviews five studies: Costanza et al. (1997), MEA report (2005a, 2005b), TEEB (2012), Daily (1997), and IPBES report (2019). The review begins by examining the evolution and growth of the ES research in economic contexts. It presented how different conceptual frameworks were applied in ES research to show connections of ES with human well-being that contextualizes valuation.Wetlands are multi-functional ecosystems that contribute immensely to human well-being. The studies on wetland ecosystems (WES) have been mostly covered in many developed countries and few developing countries. The second part of the study focuses on reviewing three aspects of wetland studies: (1) how do we define wetlands and how different ES of wetlands can be categorized? (2) what were the causes and impacts of wetland loss and degradation? (3) what do the empirical valuation studies mainly focus on? What were the research objectives, especially the wetland meta-analysis studies?Based on these questions, the study lays out research objectives and hypotheses to be tested in the future studies. The future study can undertake a systematic review and meta-analysis on wetland valuations studies in the Indian context. It can source studies from the ESVD and Indian EVL tool databases, and literature searches on Scopus, Web of Science, etc. The studies should reflect on the causal linkages, such as wetland area and wetland values, population density and wetland values, etc