Ecological base flow in Niya River Basin under climate change [气候变化背景下尼雅河流域生态基流研究]

作者：Hu K.; He J.; Zhao J.; Su L.^*; Zhang Y.

来源：Arid Land Geography, 2022, 45(5): 1472-1480.

DOI：10.12118/j.issn.1000-6060.2021.476

• assurance
• climate change
• ecological base flow
• hydrologic method
• Niya River

Watershed ecological base flow is crucial for the health and stability of river ecosystems. On the basis of meteorological data obtained by the meteorological station of Minfeng County, Xinjiang, China during 1958—2018 and hydrological data obtained by four hydrological monitoring sections in the Niya River from 1978—2018, we reveal the response of ecological base flow to climate change using trend fitting, Tennant method, correlation analysis, and regression model to analyze the climate change, determine the ecological base flow, and explore its spatiotemporal differentiation and guarantee rate change. Results show that air temperature and precipitation increased at a rate of 0.22 ℃·(10a)?1 and 3.8 mm·(10a)?1, respectively, in the past 61 a. For Niya Reservoir, 818 Canal Head, Niya hydrology station, and Niya Canal head, the recommended annual ecological base flow values are 1.989 m3·s?1, 2.188 m3·s?1, 1.755 m3·s?1, and 1.702 m3·s?1, respectively. The interannual minimum and maximum of the ecological base flow occurred in 1980 and 2010, respectively; the annual maximum occurred in July, and the minimum occurred in January or December. Spatially, it is higher in the upper reaches and lower in the lower reaches, with the highest at the head of 818 Canal and the lowest at the head of Niya Canal. The annual average ecological base current guarantee rate of each station is 50%, 45%, 50%, and 45%, respectively, and it is significantly higher during the flood season than the nonflood season. A significant correlation exists between annual and monthly ecological base flow and temperature and precipitation at the 0.01 level, but it is sensitive to temperature in spring and summer, and to precipitation in autumn and winter. The coupling effect of regression models of all hydrological sections is similar, with the basin overall regression equation obtaining R2=0.365. The response of ecological base flow to climate change has the characteristics of integrity and attenuation. These results can provide a reference for ecological water diversion and water ecological restoration in the Niya River Basin.

• 单位
  荒漠与绿洲生态国家重点实验室; 中国科学院大学