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Dryland lakes are indispensable to regional water resource systems. Ebinur Lake, the largest saline lake in Xinjiang Uygur Autonomous Region, is vital for regional biodiversity and environmental stability but has been facing the predicament of gradual shrinkage in recent decades. In this study, we proposed a new dual-index method for Landsat (-5, -7, -8, and -9) data to extract water with the combinations of the normalized difference water index (NDWI) and the modified NDWI for turbid waters (NDWIturbid). The dual-index method showed a high overall accuracy of 96.36% for Ebinur Lake. Landsat series images from 1992 to 2023 were employed to acquire the water areas of Ebinur Lake. The results showed that, over the past three decades, the area of Ebinur Lake exhibited a fluctuating decreasing trend, with an average lake area of 568.74 ± 152.43 km². The northwest intermittent water areas showed significant changes, and there was a close connection between the northwest and core water areas. Seasonally, the lake area decreased from spring to autumn. River inflow, driven by rainfall and human activities, was the primary factor affecting the inter/inner annual changes in Ebinur Lake. Furthermore, due to the valley effects, wind was found to be a critical factor in the diurnal changes in the water areas. This study should deepen the understanding of the variations of Ebinur Lake and benefit local water resource management. [ABSTRACT FROM AUTHOR]

Despite a great deal of research about airflow sensors by far, it is still hard to maintain ultra‐low limit of detection, short response, and recovery time under humid and rainy environment, which compromises its practical applications. Herein, a robust bridge‐type airflow sensor base on flexible superhydrophobic carbon nanotube fiber thin films is developed, which can not only own remarkable sensitive properties with ultra‐low limit of detection, fast response, and rapid recovery, but also exclude the influence of moisture or water drops in real applications. Both response time and recovery time are reduced compared with that of the previously reported flexible carbon‐based airflow sensors. Particularly, recovery time is reduced by ≈2/3. Meanwhile, the superhydrophobic structure renders normal functioning of the sensor in severe environment of high humidity or even in the rain, so that the influence of moisture and raindrops can be excluded, a property deficient in the previously reported airflow sensors. Not only can the sensor detect ambient airflow sensitively, but it also exhibits outstanding performance in respiratory health monitoring. Hence, the novel sensor designed in this work realizes operation in the environment of high humidity and rain, which tremendously uplifts the applicability of flexible sensors. [ABSTRACT FROM AUTHOR]

Eutrophication and warming are changing the functioning of lake ecosystems, and their impacts on lake carbon dioxide (CO2) variability have received increasing attention. However, how eutrophication and warming change lakes' carbon cycle has not been determined. Here, the surface partial pressure of CO2 (pCO2) and CO2 flux in Lake Taihu, a large and eutrophic lake in eastern China, was investigated based on monthly samplings over a 24‐yr period (1992–2015), during which the lake experienced profound anthropogenic and climate changes. The results showed that eutrophication caused by nutrient enrichment plays a role in three aspects: (1) nutrient concentrations controlled the CO2 variability on decadal scales; (2) peak pCO2 and CO2 fluxes occurred in river mouths due to large external nutrient loading inputs; and (3) eutrophication effects on CO2 varied among subzones, which was linked to external inputs and in‐lake primary production. Meanwhile, temperature controls the seasonal variation in CO2 by stimulating primary production, leading to significantly lower pCO2 and CO2 fluxes in warm seasons with algal blooms. Further analysis suggested that temperature effects varied spatially and temporally, high nutrient loading may confound the temperature effects via stimulating CO2 production. To our knowledge, this study presents the longest field measurements (24 yr) of CO2 from such large and ice‐free freshwater lakes with monthly surveys, which may provide a powerful example to demonstrate that eutrophication and warming can shape CO2 variability from a temporal perspective. Future studies should focus on the interactive warming and eutrophication effects to accurately predict future CO2 emission. [ABSTRACT FROM AUTHOR]

Inland waters emit large amounts of carbon dioxide (CO 2 ) to the atmosphere, but emissions from urban lakes are poorly understood. This study investigated seasonal and interannual variations in the partial pressure of CO 2 (pCO 2 ) and CO 2 flux from Lake Wuli, a small eutrophic urban lake in the heart of the Yangtze River Delta, China, based on a long-term (2000-2015) dataset. The results showed that the annual mean pCO 2 was 1030 ± 281 μatm (mean ± standard deviation) with a mean CO 2 flux of 1.1 ± 0.6 g m -2 d -1 during 2000-2015, suggesting that compared with other lakes globally, Lake Wuli was a significant source of atmospheric CO 2 . Substantial interannual variability was observed, and the annual pCO 2 exhibited a decreasing trend due to improvements in water quality driven by environmental investment. Changes in ammonia nitrogen and total phosphorus concentrations together explained 90% of the observed interannual variability in pCO 2 (R 2  = 0.90, p < 0.01). The lake was dominated by cyanobacterial blooms and showed nonseasonal variation in pCO 2 . This finding was different from those of other eutrophic lakes with seasonal variation in pCO 2 , mostly because the uptake of CO 2 by algal-derived primary production was counterbalanced by the production of CO 2 by algal-derived organic carbon decomposition. Our results suggested that anthropogenic activities strongly affect lake CO 2 dynamics and that environmental investments, such as ecological restoration and reducing nutrient discharge, can significantly reduce CO 2 emissions from inland lakes. This study provides valuable information on the reduction in carbon emissions from artificially controlled eutrophic lakes and an assessment of the impact of inland water on the global carbon cycle., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)