Paper short abstract:

Indigenous soil knowledge can increase the potential for collective action, but should not be overestimated. Soil knowledge and collective action focus on sustainable soil management and ecological environment, which provides an alternative understanding of soil.

Paper long abstract:

In the Anthropocene, the dynamic relationship between population pressure and land use has brought an increasing attention to the study of soil use practices, in which soil knowledge and collective action play a prominent role. Soil knowledge can not only influence collective action that improve soil function and productive, but could also harm the landscape. The historical process of natural disasters, landscape transformation, population growth and agricultural activity in Qilu Lake watershed, Yunnan Province, China makes this area an interesting case. With the aim to evaluate how soil knowledge and collective action are involved in soil management, we (i) characterized long-term land cover change with satellite photography, (ii) evaluated the ecological impact with soil sampling, laboratory analysis and Unmanned Aerial Vehicle (UAV) image, and (iii) investigated indigenous soil knowledge and collective action through field survey. We find that farmers took collective action to improve soil texture, such as using stone pits from nearby mountain areas, applying organic fertilizers, deep plowing and shallow planting. These human activities sped up the processes including farmland expansion, water reduction and deterioration, and ecological environment damage of the watershed. The implementation of indigenous soil knowledge should be guided under sustainable soil management strategy. Recent Chinese government policies such as river chief system and demarcation of ecological protection red line have promoted sustainable watershed development. Leveraging the complementarity of indigenous soil knowledge and modern soil science is highlighted as an overall strategy for sustainable soil management, which helps bridge the gap between sociocultural and physical research.