Seasonal climate variability, human activity, and terrace mitigation of erosion in the Hani rice terraces, China, in 2020

The Hani Terrace, a UNESCO agricultural heritage site in China, exemplifies soil and water conservation through its integrated forest-village-terrace-water system. However, seasonal climate variability and increased human activity are raising soil erosion risks, with seasonal patterns and drivers remaining insufficiently understood. This study employs high-resolution remote sensing to map soil erosion dynamics in the Hani Terrace core area. Results show a mild annual erosion rate of 8.69 t/hm², with only 1.57 % of the area at high risk. Erosion peaks in the second quarter (73.33 % of annual loss) are driven by climate-intensified rainfall coinciding with human land-preparation activities that minimize vegetation cover. Terracing reduces erosion by 58.5 % compared to non-terraced areas (12.28 t/hm²) by shortening slope lengths and increasing plant cover. These 2020 findings clarify the seasonal drivers of soil erosion and quantify the protective effect of terracing, providing practical guidance for improving ecological resilience and soil-water management in mountainous heritage landscapes.