Scientific literature on freshwater ecosystem services: trends, biases, and future directions

The aim of this study was to conduct a systematic review of the scientific literature on aquatic ecosystem services. We used the Web of Science database for our research. We found a total of 1,367 articles, with 837 papers that studied ecosystem services provided through the interaction between terrestrial and aquatic environments (terrestrial-aquatic papers) and 530 papers relating only to aquatic environments. Despite the growing number of articles, there is still less research on aquatic environments compared to terrestrial environments. We found a correlation between types of services and taxonomic groups, such that supporting ecosystem services were investigated using mainly macroinvertebrate, microorganisms and aquatic macrophytes communities, while provisioning and cultural ecosystem services were frequently studied with fishes. The analysis of keywords revealed that there was a temporal shift in the terms studied, and some words presented a higher frequency in aquatic research. Nonetheless, other words appeared in aquatic and terrestrial-aquatic studies with similar frequencies. The trends and biases detected in the present paper can help us to understand the role of aquatic biodiversity in ecosystem services more fully in the future as well as assist in the creation of strategies for future studies on the conservation of these services.