Abstract. Data and knowledge of surface water bodies (SWB), including large lakes andreservoirs (surface water areas > 1 km2), are critical forthe management and sustainability of water resources. However, the existingglobal or national dam datasets have large georeferenced coordinate offsetsfor many reservoirs, and some datasets have not reported reservoirs andlakes separately. In this study, we generated China's surface water bodies,Large Dams, Reservoirs, and Lakes (China-LDRL) dataset by analyzing allavailable Landsat imagery in 2019 (19 338 images) in Google Earth Engine andvery-high spatial resolution imagery in Google Earth Pro. There were∼ 3.52 × 106 yearlong SWB polygons in China for2019, only 0.01 × 106 of them (0.43 %) were of large size(> 1 km2). The areas of these large SWB polygons accountedfor 83.54 % of the total 214.92 × 103 km2 yearlongsurface water area (SWA) in China. We identified 2418 large dams, including624 off-stream dams and 1794 on-stream dams, 2194 large reservoirs (16.35 × 103 km2), and 3051 large lakes (73.38 × 103 km2). In general, most of the dams and reservoirs in Chinawere distributed in South China, East China, and Northeast China, whereasmost of lakes were located in West China, the lower Yangtze River basin, andNortheast China. The provision of the reliable, accurate China-LDRL dataseton large reservoirs/dams and lakes will enhance our understanding of waterresources management and water security in China. The China-LDRL dataset ispublicly available at https://doi.org/10.6084/m9.figshare.16964656.v3 (Wang et al., 2021b).
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Gainers and losers of surface and terrestrial water resources in China during 1989–2016
Data and knowledge of the spatial-temporal dynamics of surface water area (SWA) and terrestrial water storage (TWS) in China are critical for sustainable management of water resources but remain very limited. Here we report annual maps of surface water bodies in China during 1989–2016 at 30m spatial resolution. We find that SWA decreases in water-poor northern China but increases in water-rich southern China during 1989–2016. Our results also reveal the spatial-temporal divergence and consistency between TWS and SWA during 2002–2016. In North China, extensive and continued losses of TWS, together with small to moderate changes of SWA, indicate long-term water stress in the region. Approximately 569 million people live in those areas with deceasing SWA or TWS trends in 2015. Our data set and the findings from this study could be used to support the government and the public to address increasing challenges of water resources and security in China.
more » « less- Award ID(s):
- 1911955
- NSF-PAR ID:
- 10170213
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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