The Xiaolangdi Reservoir is the second largest water conservancy project in China and the last comprehensive water conservancy hub on the mainstream of the Yellow River, playing a vital role in the middle and lower reaches of the Yellow River. To study the effects of the construction of the Xiaolangdi Reservoir (1997-2001) on the runoff and sediment transport in the middle and lower reaches of the Yellow River, runoff and sediment transport data from 1963 to 2021 were based on the hydrological stations of Huayuankou, Gaocun, and Lijin. The unevenness coefficient, cumulative distance level method, Mann-Kendall test method, and wavelet transform method were used to analyze the runoff and sediment transport in the middle and lower reaches of the Yellow River at different time scales. The results of the study reveal that the completion of the Xiaolangdi Reservoir in the interannual range has little impact on the runoff in the middle and lower reaches of the Yellow River and a significant impact on sediment transport. The interannual runoff volumes of Huayuankou station, Gaocun station, and Lijin station were reduced by 20.1%, 20.39%, and 32.87%, respectively. In addition, the sediment transport volumes decreased by 90.03%, 85.34%, and 83.88%, respectively. It has a great influence on the monthly distribution of annual runoff. The annual runoff distribution is more uniform, increasing the runoff in the dry season, reducing the runoff in the wet season, and bringing forward the peak flow. The runoff and Sediment transport have obvious periodicity. After the operation of the Xiaolangdi Reservoir, the main cycle of runoff increases and the second main cycle disappears. The main cycle of Sediment transport did not change obviously, but the closer it was to the estuary, the less obvious the cycle was. The research results can provide a reference for ecological protection and high-quality development in the middle and lower reaches of the Yellow River.
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http://dx.doi.org/10.3390/ijerph20054351 | DOI Listing |
PLoS One
January 2025
Institute for Studies in County Development, Shandong University, Qingdao, Shandong, China.
This research mainly explored the effects of mergers and acquisitions (M&As) on the financial performance of Chinese listed companies and the determinants of post-M&A financial performance of mergers by incorporating adjustments for business cycle fluctuations. The research was divided into two parts. The first part applied data envelopment analysis (DEA) models for the calculation of the financial performance scores of mergers and non-mergers in six major sectors before and after M&As.
View Article and Find Full Text PDFGlob Chang Biol
January 2025
Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, China.
The carbon sink function performed by the different vegetation types along the environmental gradient in coastal zones plays a vital role in mitigating climate change. However, inadequate understanding of its spatiotemporal variations across different vegetation types and associated regulatory mechanisms hampers determining its potential shifts in a changing climate. Here, we present long-term (2011-2022) eddy covariance measurements of the net ecosystem exchange (NEE) of CO at three sites with different vegetation types (tidal wetland, nontidal wetland, and cropland) in a coastal zone to examine the role of vegetation type on annual carbon sink strength.
View Article and Find Full Text PDFExamining the impacts of natural and anthropogenic influences on aquatic macrophytes in shallow lakes is crucial for their effective restoration and management. However, there is a lack of direct evidence regarding past species composition or detailed and continuous evidence of recent changes in aquatic macrophyte communities. This study utilized plant macrofossil remains deposited in the sediment, combined with macrophyte surveys from 1983 to 2010, to reconstruct the historical changes in the macrophyte community over approximately 160 years in Lake Weishan, a sub-lake of Lake Nansi located in the lower Yellow River (Huanghe River) Basin, northern China.
View Article and Find Full Text PDFEnviron Res
January 2025
College of Energy and Environment, Inner Mongolia University of Science and Technology,Baotou 014010, P. R. China; Collaborative Innovation Center of Autonomous Region for Ecological Protection and Comprehensive Utilization in the Inner Mongolia Section of the Yellow River Basin, Baotou 014010, P. R. China. Electronic address:
The coexistence of different microbial communities is fundamental to the sustainability of many ecosystems, yet our understanding of the relationships among microbial communities in plateau cold-region lakes affected by seasonal ice cover remains limited. This research involved investigating three lakes in the Inner Mongolia segment of the Yellow River basin during frozen and unfrozen periods in two habitats: water bodies and sediments. The research examined the composition and function of bacteria, archaea, and fungi across different times and habitats within the basin, their response to environmental variables in water and sediment, and inter-domain interactions between bacteria-archaea and bacteria-fungi were compared using interdomain ecological network (IDEN).
View Article and Find Full Text PDFFront Public Health
January 2025
Department of Epidemiology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China.
Introduction: Facing Mount Tai in the south and the Yellow River in the north, Zibo District is an important petrochemical base in China. The effect of air pollution on cardiovascular diseases (CVDs) in Zibo was unclear.
Methods: Daily outpatient visits of common CVDs including coronary heart disease (CHD), stroke, and arrhythmia were obtained from 2019 to 2022 in Zibo.
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