近 60 年人类活动对洛川塬典型沟道侵蚀演化的影响

In order to reveal the impact of human activity on the erosion of gullies on the Loess Plateau of China, remote sensing and geographic information technology were used to characterize the erosion history of three typical gully channels in the Luochuan tableland over the past 60 years, and explore the influence of different types of human activity on the evolution of gully erosion. Results showed that from 1965 to 2018, the Heimugou gully head expanded by an average rate of 391 m² per year. Due to urban development, an area of 78 480 m² of the gully head in the heimugou catchment were artificially backfilled. Land use change analysis showed that urban expansion (increased human activity) aggravated gully headcut erosion, while human backfilling activity consolidated the gully head, thereby controlling the gully headcut erosion. From 1966 to 2020, the Si′er gully near the Jiuxian town expanded by 11 542 m², and the gully expansion was closely related to residential construction and traffic roads hardening. From 2013 to 2020, the area of the Si′er gully head reduced by 12 404 m², which was related to the construction of water collection ponds in the gully edge and the consolidation of gully head through backfilling. From 1966 to 2020, the Nangou gully near the Jiuxian town expanded by 5008 m². The main reason may be that the impervious surface of the Jiuxian town increased surface runoff and aggravated gully erosion. From 1966 to 2020, two channels near the Wanfeng tower expanded by an average rate of 1092 m² per year, and the main reason can be attributed to the irrational agricultural activities of humans. From 2008 to 2020, the area expansion rates of the two gully channels decreased, indicating that soil and water conservation measures had been strengthened in the tableland surface layer to control gully erosion.