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In this study, trend analysis of the lake surface areas was performed on the Google Earth Engine (GEE) platform in the period of 1985-2022 with Landsat 5/7/8/9 (TM) (ETM +), and (OLI) satellite images. The study analyzed 10 lakes, including Acigol, Aksehir, Beysehir, Burdur, Egirdir, Ilgin, Isikli, Karatas, Salda, and Yarisli in the Türkiye Lakes Region. In this analysis, the normalized differentiated water index was calculated for each of the 3147 satellite images, and water surfaces were extracted from other details using Otsu's threshold method. In the study's accuracy, the overall accuracy and F1-score values were calculated to be over 90% for all lakes. Moreover, the relationship between the changes in the surface areas of the lakes was evaluated using correlation analysis, with the sea surface temperature obtained from the NOAA satellite and the evaporation, temperature, and precipitation parameters obtained from the Era-5 satellite being used. In addition, the change of the area on the lake surface was analysed using Mann-Kendall (MK), Sen's slope, and sequential MK test statistics. During the 37 years between 1985 and 2022, there was no significant change in the Acigol surface area, but a slight increasing trend was observed. Decreases of 76.07, 4.68, 41.77, 5.44, 37.56, 28.97, 78.65, 7.26, and 81.02% were determined in the lakes of Aksehir, Beysehir, Burdur, Egirdir, Ilgin, Isikli, Karatas, Salda, and Yarisli, respectively. The application of this method in the lakes region and monitoring these lakes, which are of great importance for Türkiye, provide valuable information in determining the lakes' organizational strategies., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

An increase in the human population, urbanization, industrialization, infrastructural development, and current agricultural practices acts as major factors leading to the decline of the groundwater table in the region. The present study analyzes the noticeable effect of anthropogenic pressure on the groundwater table in the Bist-Doab region in Punjab, India, from 1996 to 2016. Statistical techniques, viz., Mann-Kendall Z statistics and Sen's slope, were used to estimate the water table decline in the area. The results indicate that there was a slight increase in the groundwater table in the Kandi belt of Siwalik foothills and south-western parts of the region. In the rest of the areas, a significant declining trend was observed in the groundwater table. The decline in the water table ranged from 56 to 149 cm per year in the pre- and post-monsoon seasons due to increasing in rice cultivated area, which is an alarming situation in the aquifer system of the region. Hence, to reduce the further decline of the groundwater table, water management practices need to be encouraged in the region. There is requiring immediate attention to change the present land-use/cover practices and to grow less water-consuming crops instead of high water-consuming crops to reduce the pressure on groundwater.