Abstract: The riparian zone range of the Tang River was delineated by remote sensing interpretation and field investigation, and the changes in the ecosystem service value of the riparian zone from 1987 to 2021 were evaluated by the equivalent factor method. The results showed that from 1987 to 2021, the total ecosystem services value of the riparian zone in the upper reaches of the Tang River increased by 6.854 2 million yuan. The value change was caused by the decrease of construction land area and the increase of forest and grass area. The landscape pattern developed in the direction of higher ecological benefits. The total ecosystem services value of the riparian zone in the middle reaches of the Tang River increased by 115.079 4 million yuan from 1987 to 2021, but there was a trend of decrease in the service value from 2011 to 2021. The increase in the early stage was related to the increase in the area of wetland water storage and the recovery of vegetation area, which led to the improvement of the service value of water and forest land. The total ecosystem services value of the riparian zone in the lower reaches of the Tang River showed a trend of increasing first and then decreasing, but the overall trend was rising, with an increase of 15.6059 million yuan. The reason was that the gradual increase in the area of forest from 1987 to 2011 led to an increase in the ecosystem services value, while the decrease in the area of forest and water body from 2011 to 2021 led to a decrease in the ecosystem services value.

Key words: ecosystem service value, equivalent factor method, remote sensing interpretation, field investigation, riparian zone of Tang River