2.2 Data collection
The data used in this study include
the following contents.
(1)
The weather in flood and dry seasons in the Poyang Lake basin is
primarily cloudless. This study chose this period’s images to analyze to
avoid cloud cover interference on sensing images. The remote sensing
images of Poyang Lake Basin are from the Landsat series (MSS, TM, ETM+,
OLI). Data distribution is from 1977 to 2021(Fig.2), downloaded from the
United States Geological Survey (USGS, website athttps://earthexplorer.usgs.gov//).
Selected high-quality images with a suitable extraction effect, and the
extraction results passed visual inspection. Finally, 328 images were
screened by excluding missing data from 1980, 1982, 1985, 1994, and
2009. (2) To better reflect the lake changes, we compared historical
images of Poyang Lake with earlier periods of less anthropogenic
disturbance. The historical images were high-resolution satellite images
on December 13, 1967, taken by the USGS (website athttps://earthexplorer.usgs.gov//).
Visual inspection showed that the extraction results were accurate. (3)
Runoff and sediment data were obtained from the actual measurements of
hydrological stations in the Poyang Lake basin and lake estuary (Fig.1),
recorded in the Hydrology Data Yearbook published by the Ministry of
Water Resources and Power, PRC. Runoff data distribution period 1977 to
2020, sediment data distribution period 1980 to 2020. (4) Temperature
and precipitation data of the Poyang Lake Basin were obtained from 23
measurements of meteorological stations (Fig.1), downloaded data from
the China Meteorological Data Network
(http://data.cma.cn/). Data
distribution period 1977 to 2020. (5) The land use data of Poyang Lake
Basin were obtained from China National Land Use Database and have been
classified by a secondary classification system. Selected 1980, 1995,
2000, 2005, 2010, 2015, and 2020 land use data. All measured data used
in this study were checked and rated as good quality.