Changes of water clarity in large lakes and reservoirs across China observed from long-term MODIS

Wang，Shenglei1,2; Li，Junsheng2,3; Zhang，Bing2,3; Lee，Zhongping4; Spyrakos，Evangelos5; Feng，Lian6; Liu，Chong7; Zhao，Hongli8; Wu，Yanhong2; Zhu，Liping7; Jia，Liming9; Wan，Wei1; Zhang，Fangfang2; Shen，Qian2; Tyler，Andrew N.5; Zhang，Xianfeng1

2020-09-15

10.1016/j.rse.2020.111949

REMOTE SENSING OF ENVIRONMENT   影响因子和分区

0034-4257

1879-0704

Water clarity is a well-established first-order indicator of water quality and has been used globally by water regulators in their monitoring and management programs. Assessments of water clarity in lakes over large temporal and spatial scales, however, are rare, limiting our understanding of its variability and the driven forces. In this study, we developed and validated a robust Secchi disk depth (Z) algorithm for lakes across China based on two water color parameters, namely Forel-Ule Index (FUI) and hue angle α, retrieved from MODIS data. The MODIS Z model shows good results when compared with in-situ measurements from 17 lakes, with a 27.4% mean relative difference (MRD) in the validation dataset. Compared with other empirical Z models, our FUI and α-based model demonstrates improved performance and adaptability over a wide range of water clarity and trophic states. This algorithm was subsequently applied to MODIS measurements to provide a comprehensive assessment of water clarity in large lakes (N = 153) across China for the first time. The mean summer Z of the studied lakes between 2000 and 2017 demonstrated marked spatial and temporal variations. Spatially, the Z of large lakes presented a distinct spatial pattern of “high west and low east” over China. This spatial pattern was found to be associated with the significant differences in lake depth and altitude between west and east China while China's population, GDP, temperature, and precipitation distribution have also contributed to a certain extent. Temporally, the Z of most lakes increased during this period, with an overall mean rate of 3.3 cm/yr for all lakes. Here, 38.6% (N = 59) of the lakes experienced a significant increase in their Z value during the past 18 years while only 8.5% (N = 13) showed a significant decreasing trend. Significant increases in lake Z were observed in west China, which were found to correlate with the increase of air temperature and lake surface area. This is possibly a response of the lakes in west China to climate change. In the lake systems of east China, which are predominately used as a drinking water source, the increase in lake Z was found to be strongly correlated with changes in local GDP (gross domestic production), NDVI (normalized difference vegetation index) and lake surface area, suggesting a combined effect of the implemented management practices and climatic variability. The results of this study provide important information for water quality conservation and management in China, and also highlight the value of satellite remote sensing in monitoring water quality over lakes at a large scale and long-term.

FUI Hue angle Lakes and reservoirs MODIS Secchi disk depth Water clarity changes

SCI ; EI

英语

ESI高被引

其他

National Key Research and Development Program of China[2017YFC0405804] ; National Natural Science Foundation of China[41901272][41971318] ; China Postdoctoral Science Foundation[8206300163]

Environmental Sciences & Ecology ; Remote Sensing ; Imaging Science & Photographic Technology

Environmental Sciences ; Remote Sensing ; Imaging Science & Photographic Technology

WOS:000549189200047

ELSEVIER SCIENCE INC

20202608878966

Radiometers ; Climate change ; Potable water ; Water quality ; Reservoirs (water)

Reservoirs:441.2 ; Atmospheric Properties:443.1 ; Water Resources:444 ; Water Analysis:445.2 ; Radiation Measuring Instruments:944.7

GEOSCIENCES

2-s2.0-85086897159

Scopus

1.School of Earth and Space Sciences,Peking University,Beijing,China
2.Key Laboratory of Digital Earth Science,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing,China
3.University of Chinese Academy of Sciences,Beijing,China
4.School for the Environment,University of Massachusetts Boston,Boston,United States
5.Biological and Environmental Sciences,Faculty of Natural Sciences,University of Stirling,Stirling,United Kingdom
6.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,China
7.Key Laboratory of Tibetan Environment Changes and Land Surface Processes,Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing,China
8.China Institute of Water Resources and Hydropower Research,Beijing,China
9.Environmental Monitoring Central Station of Heilongjiang Province,Harbin,China

Wang，Shenglei,Li，Junsheng,Zhang，Bing,et al. Changes of water clarity in large lakes and reservoirs across China observed from long-term MODIS[J]. REMOTE SENSING OF ENVIRONMENT,2020,247.

Wang，Shenglei.,Li，Junsheng.,Zhang，Bing.,Lee，Zhongping.,Spyrakos，Evangelos.,...&Zhang，Xianfeng.(2020).Changes of water clarity in large lakes and reservoirs across China observed from long-term MODIS.REMOTE SENSING OF ENVIRONMENT,247.

Wang，Shenglei,et al."Changes of water clarity in large lakes and reservoirs across China observed from long-term MODIS".REMOTE SENSING OF ENVIRONMENT 247(2020).