Insights, implications and challenges of studying local soil knowledge for sustainable land use: a critical review

Local soil knowledge (LSK) has been recognised for its importance in sustainable soil management and agroecosystems. This paper examines peer-reviewed articles and grey literature documents on LSK during 2003–2018. Research continues to be geographically focused on developing countries, but often in collaboration with researchers from developed countries. There were five key research themes: soil classification and agreement between local and scientific soil knowledge (Theme 1), value of LSK for soil management and decision-making (Theme 2), scientific approach to the incorporation of LSK (Theme 3), application of LSK for identification of and solutions to soil problems (Theme 4) and factors influencing soil knowledge development (Theme 5). Although Theme 1 continued to be a prevalent research area, confirming the importance of visible and topsoil characteristics identified by farmers, examining subsurface soil properties has garnered less research. For LSK to be thoroughly documented requires support by a pluralistic scientific assessment and greater incorporation of social science methodologies. An overarching finding from Themes 2–4 was the importance of designing national programs that incorporate LSK derived from local people and other stakeholders (e.g. scientists and policymakers) to conserve soils. Local soil maps, using LSK terminology, could broaden the appeal and use of maps by local stakeholders to support sustainable land-use planning from the field to national policy-making processes. Finally, cultural and political aspects, known to influence LSK, should be given greater consideration in further research to sustain and develop this knowledge (Theme 5).