Data of annual lake area in the endorheic basin of the Qinghai-Tibet Plateau from 1986 to 2019

This data provides the annual lake area of ​​582 lakes with an area greater than 1 km2 in the enorheic basin of the Qinghai-Tibet Plateau from 1986 to 2019. First, based on JRC and SRTM DEM data, 582 lakes are identified in the area that are larger than 1 km2. All Landsat 5/7/8 remote sensing images covering a lake are used to make annual composite images. NDWI index and Ostu algorithm were used to dynamically segment lakes, and the size of each lake from 1986 to 2019 is then calculated. This study is based on the Landsat satellite remote sensing images, and using Google Earth Engine allowed us to process all Landsat images available to create the most complete annual lake area data set of more than 1 km2 in the Qinghai-Tibet Plateau area; A set of lake area automatic extraction algorithms were developed to calculate of the area of ​​a lake for many years; This data is of great significance for the analysis of lake area dynamics and water balance in the Qinghai-Tibet Plateau region, as well as the study of the climate change of the Qinghai-Tibet Plateau lake.

0 2022-04-19

Phytoplankton data of lakes in Qinghai Tibet Plateau in 2020

The data is the phytoplankton data of 70 points in 26 lakes in Tibet in 2020. The sampling time is from August to September. The sampling method is the conventional phytoplankton sampling method. 1.5 liters of samples are collected, fixed by Lugo's solution, siphoned and concentrated after static precipitation, and the results are examined by inverted microscope. The data includes the density data of different phytoplankton of 77 species / genus in 10 categories, including diatom, green algae, cyanobacteria, dinoflagellate, naked algae, cryptoalgae, brown algae, brown algae and CHAROPHYTA. This data is original and unprocessed. The unit is piece / L. The data can be used to characterize the composition and abundance of phytoplankton in the open water areas of these lakes, and can also be used to calculate the diversity of phytoplankton communities in these lakes.

0 2022-04-15

Benthic macroinvertebrate data of Tibet lakes (2020)

Through the semi-quantitative collection method, benthos research was carried out in 22 lakes in the core area of Qiangtang and Yamzho Lake in the summer of 2020. The relative abundance data of Zoobenthos in alpine lakes in Tibet were obtained by the mixed sampling of littoral and deep-water communities. The results of this data show that among the 6420 selected benthos, 28 species of benthos are identified, belonging to 3 phyla and 7 classes, of which the main benthic groups are gammarus and chironomid, and the dominant species in a few lakes are water beetles. This data improves the recognition accuracy and cognitive range of Zoobenthos in Tibet and will provide a reference for the evaluation of aquatic animal diversity and fishery resources in plateau lakes.

0 2022-04-02

The variations of hydrological elements in ten lakes in Jiangsu Province (2003-2019)

The data set contains the variations of water level, area, and volume for ten lakes in Jiangsu Province (Taihu Lake, Hongze Lake, Gaoyou Lake, Luoma Lake, Shijiu Lake, Gehu Lake, Yangcheng Lake, Baima Lake, Shaobo Lake and Dianshan Lake) from 2003 to 2019, which provides important parameters for the study of lake hydrological ecosystem balance in Jiangsu Province in recent years. The water level data of the ten lakes were obtained from altimetry satellites Envisat/RA-2, Cryosat-2, ICESat, and ICESat-2. The water area data were obtained from Landsat TM/OLI images bsed on Modified Normalized Difference Water Index. For the four lakes with complete water level data (Hongze Lake, Gaoyou Lake, Gehu Lake and Taihu Lake), the water volume changes from 2003 to 2019 were estimated according to the water level and area results. Compared with the in-situ water level data, the water level extracted from altimetry data showed significantly consistent (α = 0.05) for all the ten lakes, with the average absolute error of 0.168 m. The data set provides the variations of water level, area, and volume for the ten lakes in Jiangsu Province from 2003 to 2019, which can provide data support for the management and dispatching of water resources in Jiangsu Province.

0 2021-09-24

Total organic carbon, total nitrogen and total inorganic carbon in surface sediments of Qinghai Lake (2017)

In 2017, 27 surface sediments were collected in Qinghai Lake by gravity sampler, and the top 1cm was taken as the surface layer, which was freeze-dried and ground into powder after being taken back to the laboratory. Before testing the content of organic carbon and nitrogen, 1mol / L hydrochloric acid should be used to stir the reaction for more than 10 hours, so that the carbonate is completely removed, then dried and ground, and the organic carbon and nitrogen are tested on the element analyzer. The total inorganic carbon content is the carbonate content of the whole rock powder sample measured by infrared spectrum, which is then calculated as the total inorganic carbon content. The contents of organic carbon and inorganic carbon constitute the total carbon content of the lake, and they are close to each other, indicating that the inorganic carbon burial flux and organic carbon burial flux of Qinghai Lake are similar.

0 2021-06-10

Optical stimulated luminescence ages of the mega-lakes in the northwestern Tibetan Plateau

Paleo-shorelines are widely developed in the lakes of the Tibetan Plateau (TP), which record the history of paleo-lake level changes. The development age of the mega-lake represented by the highest paleo-shoreline is controversial. The age of the shoreline or the mega-lake can be obtained by measuring the burial age of the shoreline sand in the sedimentary strata of the paleo-shoreline by using the optical stimulated luminescence (OSL) dating technology. This data includes the OSL ages of the highest paleo-shorelines of three lakes in the northwestern TP. The dating is based on the K-feldspar pIRIR method developed in recent years, which effectively solves the problem that the quartz OSL signal is not suitable for dating in the study area. This data can provide key information for the evolution history of the mega-lakes on the TP.

0 2021-05-31

An integrated dataset of daily lake surface temperature over Tibetan Plateau (LSWT_TPv1) (1978~2017)

This dataset is a daily lake surface water temperature (LSWT) products of 164 lakes in Tibetan Plateau from 1978 to 2017. Firstly, we calculate the mean values of lake surface pixels based on MOD11A1 products to obtained the daily lake surface temperature series from 2000 to 2017. Secondly, we modified the air2water model to simulate the lake surface temperature continuously. The daily air temperature from meteorological stations were used as forcing data, and the lake surface temperature monitored by MOD11A1 as the model calibration and validation data. Finally, the daily lake surface temperature across Tibet Plateau from 1978 to 2017 were reconstructed. Compared with the results from remote sensing monitoring, the Nash-Sutcliffe efficiency coefficients of all lakes are higher than 0.6 with bias ranging at ±0.55℃. The dataset is suitable to analyze the long-term changes of lake surface temperature over the past decades, which is of great significance for assessing the impacts of climate warming on the water and heat balance, water quality and lake ecosystem changes on the Tibetan Plateau.

0 2021-05-31

MODIS inversion of Lake transparency over 50 km2 in the Tibetan Plateau (2000-2019)

1) data content (including elements and significance): transparency data of 152 lakes greater than 50 km2 in the Qinghai Tibet Plateau in 2000-2019 (Saybolt disk value) 2) Data source and processing method: the data inversion is based on the high-precision transparency inversion model and modis-modocga product data. The remote sensing data is converted into the remote sensing reflectivity R ﹐ RS inversion transparency value, and the annual mean value is calculated. The average value of 3 × 3 pixels in the geometric center of the lake represents the lake. For the case where the geometric center is located outside the lake, the open water area of the lake is taken for calculation. 3) Data quality description: annual average value of lakes. 4) Results and prospects of data application: climate change may change Lake transparency, while the change of Lake transparency will play a feedback role in regional climate change. In this study, the inversion of Lake transparency in the Qinghai Tibet Plateau provides basic data for the energy exchange of the lake air interface.

0 2020-05-15

Data set of recent Lake area and water volume changes in the Qinghai Tibet Plateau (1976-2013)

1) area data of 317 lakes larger than 10 km2 in 1976, 1990, 2000, 2005 and 2013 were obtained based on multi temporal Landsat images; 2) Combining SRTM DEM and Landsat images, the data of lake water volume change in 1976-1990, 1990-2000, 2000-2005 and 2005-2013 were obtained; 3) The accuracy of Lake area is controlled in one pixel, and the accuracy of water volume change is about 5%; 4) This data has been applied to the study of recent changes in lake water volume in the Qinghai Tibet Plateau, and the results have been published in remote sensing of environment. In other future studies, this data can also be used as basic data, as well as in the analysis of changes in ecological environment, climate change, Lake water quality, etc

0 2020-05-15

The dataset of the lake distribution in Qinghai Lake basin (2000)

The dataset is the distribution map of lakes in Qinghai Lake Basin. The projection is latitude and longitude. The data includes the spatial distribution data and attribute data of the lake. The attribute fields of the lake are: NAME (lake name), CODE (lake code).

0 2020-04-04