A review of the commonalities and differences of values of global cropland ecosystem services

Cropland ecosystems provide the food production for humans, but their ecological and cultural multi-functionality are often overlooked. Existing assessments of cropland ecosystems value (ESV) vary significantly, mainly stem from the double counting due to overlapping categorization of ecosystem functions and the tacit assumption that all ecosystem functions are universally presented everywhere. This study provides the first comprehensive review of global cropland ESVs that are reclassified as intermediate and finial services and excludes the non-universally existence of particular ESVs with small sample, using a meta-analysis of 1,162 observations from 145 existing related studies. The results show that the unit value ranged from 894.66 to 1,241.23$/ha/year. Avoiding double counting reduces ESVs by 72%. The regulating service of cropland is more valuable than food supply. The findings of this study not only help us better understand the value of global cropland ESVs, but also have important implications for ESV studies in the future.