Ecosystem service research in the dry subtropics: Current state, temporal changes and drivers of regional variability

Abstract

Dry subtropical (DST) regions that share similar climatic and topographic conditions exhibit today significant disparities in population density, agricultural intensity, wealth and cultural values. In addition, they are also facing increasing pressures on their natural resources. These attributes collectively shape individuals' varying dependence on natural resources and may influence their perception of ecosystem services (ES). In this study, we conducted a systematic literature review, focusing on the DST regions, to address two main questions: 1) What is the current state, temporal trends and regional variability in scientific research on ES and 2) What are the potential drivers of the variability in ES research? Amongst the 471 publications found in our review, 53% focused on provisioning services, followed nearly equally by cultural (33%) and regulating (30%) services. Only 13% addressed more than one ES category and approximately 33% mentioned economic valuation. Our study reveals that research on ES in the dry subtropics experienced a significant increase from 2005 onwards. Approximately 45% of the publications included the term 'ecosystem service' and its frequency has risen substantially over time. Most publications primarily focus on African dry subtropics (over 60%), followed by South and North American ones. Publications from southern Asia and NE Australia were more scarce. Importantly, we found no clear relationship between the number of publications, publication density or representativeness and the variables used as indicators of human pressure (e.g. population density). Consequently, research efforts in the DST regions appear to be influenced by a diverse range of financial and institutional constraints, international research agendas, as well as the personal interests of researchers, contributing to the idiosyncratic nature of this field.