Trends in agroforestry research over 4 decades

Agroforestry has a high potential to contribute to climate change mitigation and adaptation as a nature-based climate solution and is increasingly included as a climate strategy in international agreements and national plans. Yet, how to equitably increase and sustain agroforestry on the scale needed to meet these targets remains unclear. Examining broad trends in the existing 4 decades of agroforestry literature can highlight gaps and opportunities for future research that enables agroforestry transitions. Using text analytics and a full-text, corpus-based approach, we analyzed changes in word use in 9,664 agroforestry research articles and reports published between 1980 and 2020 with regard to 4 key themes of the social dimensions of agroforestry transitions: (1) agreements and policies; (2) scales and decision-making agents; (3) knowledge, culture, and equity; and (4) frameworks and methods. We then compared the frequency of these themes in research articles and reports. Despite the most frequently used terms across all 4 decades being primarily ecological (e.g., forest, species, soil), the lexicon of agroforestry literature has expanded to incorporate more social, economic, and political elements (e.g., livelihood, knowledge, community) over time, and as agroforestry has become more central to climate change adaptation and mitigation targets. Trends in the frequency of several terms (e.g., biodiversity, development, climate) corresponded with the signing of intergovernmental agreements, illustrating the responsiveness of the field to global priorities. Reports had a higher frequency of terms related to social themes than research articles. We discuss the implications of these emergent trends and opportunities for future research in support of sustainable and just agroforestry transitions.