Estimation of ecological water supplement for typical bird protection in the Yellow River Delta wetland

• Published in: Ecological indicators 2021-08, Vol.127, p.107783, Article 107783
• Main Authors: Yu, Xiaoyu, Zhu, Wenbin, Wei, Jiaxing, Jia, Shaofeng, Wang, Andong, Huang, Yanbo, Zhao, Yajie
• Format: Article
• Language: English
• Subjects: Ecological water supplement; Evapotranspiration; Water balance method; Waterbirds; Wetland; Yellow River Delta
• ISSN: 1470-160X; 1872-7034
• DOI: 10.1016/j.ecolind.2021.107783

[Display omitted] •Monthly ecological water supplement was estimated by water balance analysis.•Three typical birds were selected as protected objects of water supplement scheme.•Precipitation had a significant negative relation with ecological water supplement.•The total annual ecological water supplement was about 1.96×108 m3.•The water supplement in wet year was nearly 20% less than that in extreme dry year. With abundant resources in the wetland, the Yellow River Delta provides important habitats for various kinds of rare bird species. However, due to climate change and human water withdrawal activities, no-flow events of the Yellow River occurred frequently since the 1970s, resulting in serious wetland degradation and biodiversity losses. Ecological water supplement has been regarded as one of the most effective measures to cope with these environmental problems. Accordingly, how much water is required for the ecological restoration becomes an essential question to be answered. Since the primary function of the Yellow River Delta Natural Reserve (YRDNR), the typical wetland in the Yellow River Delta, is to provide suitable habitats for various rare birds, the purpose of this paper is to propose a method based on water balance analysis to specify monthly ecological water supplement for the habitats of typical birds in the YRDNR. Specifically, three typical birds were selected as the protection objects, including Grus japonensis, Ciconia boyciana, and Larus saundersi. Monthly water supplement was determined by monthly long-term time series data (2003–2018) of evapotranspiration product derived from remote sensing and meteorological data (precipitation and pan evaporation) acquired from National Meteorological Information Center. The results showed that the annual ecological water supplement for 10 km2 ideal habitats was 666.17×104 m3, 1165.22×104 m3, and 664.48×104 m3 for G. japonensis, C. boyciana, and L. saundersi, respectively. Besides, it was found that annual precipitation generally had a significant negative relation with annual ecological water supplement, which suggested that local precipitation should be considered as a key factor in determining the amount of annual water supplement. The frequency analysis was then implemented to provide reasonable scheme of actual ecological water supplement under different precipitation scenarios. The results indicated that annual ecological water supplement for the whole YRDNR was 1.81×108 m3, 1.94×108 m3, 2