1,- 1State Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agriculture and Biomanufacturing, Zhengzhou University, Zhengzhou 450001, China (liushlcn@gmail.com)
- 2State Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China
Freshwater resources have long supported gains in crop productivity, yet their sustainability is increasingly challenged by changes in both the climate system and land. As one of the most important cash crops in China, cotton has undergone notable changes in recent years, with a decline in harvest area and a shift toward dryland regions. Nevertheless, the impacts of such a transition on cotton water consumption and its underlying factors remain unclear. To address this knowledge gap, we employed the water footprint concept, spatial cluster, and decomposition analysis to depict the long-term dynamic of cotton water footprint over regions in China from 1990 to 2020, and to untangle the impacts from various aspects. Our results demonstrated that the total water footprint of cotton in China has substantially decreased, from 24.2 G m3 in 1990 to 11.9 G m3 in 2020, with a rapid decrease in the Yellow River Valley (YERV) and the Yangtze River Valley (YARV) cotton regions, while an increase in the Northwest Inland China (NIC) cotton region. These changes were accompanied by a proportion that varied from 23.5% to 7.8% for the green water footprint and from 70.1% to 87.7% for the blue water footprint, respectively. The geographical centroids of both cotton harvest area and water footprint exhibited a northwestward trend in the NIC and YERV cotton regions, while the YARV cotton region experienced a southwestward shift, along with heightened spatial coupling from the declining distance between such centroids. Changes in the climate system, harvest area, and fertiliser applications resulted in yearly variations in total water footprint over the region, with changes in harvest area driving nearly double the changes in cotton water footprint compared to climate change. Our findings underscore the importance of optimizing cropping patterns to promote sustainable water use and mitigate the adverse effects of climate change on cotton production.
How to cite: Liu, S., Zhang, C., Li, T., and Ma, X.: Harvest area exerts nearly twice the influence of climate change on long-term cotton water footprint changes in China, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15634, https://doi.org/10.5194/egusphere-egu26-15634, 2026.
