Assessment of permaculture integration into gray and mainstream scientific literature in four languages. A review

Permaculture, often described as a grassroots movement, philosophy, or set of progressive agricultural practices, is considered to have significant potential to revitalize degraded land, improve the robustness of ecosystems, reduce energy consumption, and lower operating costs while effectively sequestering carbon. Despite its growing international popularity and practical benefits, the term permaculture remains notably isolated from mainstream scientific discourse, limiting its broader integration and impact. Literature reviews on this versatile set of agricultural practices are uncommon, and this isolation from established scientific literature significantly hampers the potential of permaculture to influence and transform contemporary agricultural systems toward enhanced sustainability. Addressing this gap, this study compiles the most comprehensive collection of white and gray literature related to permaculture to date, analyzing 975 publications across four languages-English, Portuguese, Spanish, and French-through bibliometric analysis, qualitative content analysis, H-index, and citation counts. The findings reveal that permaculture retains a dynamic presence within academic discussions, being increasingly associated with critical concepts such as design, agriculture, and ecology. Notably, the use of permaculture in peer-reviewed technical publications has surged, particularly in recent study periods, marking a significant shift towards recognizing its value in mainstream scientific literature. This review aims to: 1. Gather white and gray literature related to the term permaculture across four languages. 2. Identify terms most commonly associated with permaculture using computational tools. 3. Describe the evolution of the term permaculture over time. 4. Examine whether the term permaculture is predominantly associated with philosophical or scientific perspectives in peer-reviewed literature. 5. Assess the increasing recognition of permaculture as a topic of interest in English peer-reviewed literature.