Browsing by Author "Li, Bo"
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- A data-driven model to quantify the impact of river discharge on tide-river dynamics in the Yangtze River estuaryPublication . Cai, Huayang; Li, Bo; Garel, Erwan; Pan, Haidong; Zhao, Tongtiegang; Liu, Feng; Ma, Yuting; Ou, SuyingUnderstanding the role of river discharge on tide-river dynamics is of essential importance for sustainable water management (flood control, salt intrusion, and navigation) in estuarine environments. It is well known that river discharge impacts fundamental tide-river dynamics, especially in terms of subtidal (residual water levels) and tidal properties (amplitudes and phases for different tidal constituents). However, the quantification of the impact of river discharge on tide-river dynamics is challenging due to the complex interactions of barotropic tides with channel geometry, bottom friction, and river discharge. In this study, we propose a data-driven model to quantify the impact of river discharge on tide-river dynamics, using water level time series data collected through long-term observations along an estuary with substantial variations in river discharge. The proposed model has a physically-based structure representing the tide-river interaction, and can be used to predict water level using river discharge as the sole predictor. The satisfactory correspondence of the model outputs with measurements at six gauging stations along the Yangtze River estuary suggest that the proposed model can serve as a powerful instrument to quantify the impacts of river discharge on tide-river dynamics (including time-varying tidal properties and tidal distortion), and separate the contribution made by riverine and tidal forcing on water level. The proposed approach is very efficient and can be applied to other estuaries showing considerable impacts of river discharge on tide-river dynamics.
- Extension of the general unit hydrograph theory for the spread of salinity in estuariesPublication . Cai, Huayang; Li, Bo; Gu, Junhao; Zhao, Tongtiegang; Garel, ErwanFrom both practical and theoretical perspectives, it is essential to be able to express observed salinity distributions in terms of simplified theoretical models, which enable qualitative assessments to be made in many problems concerning water resource utilization (such as intake of fresh water) in estuaries. In this study, we propose a general and analytical salt intrusion model inspired by Guo's general unit hydrograph theory for flood hydrograph prediction in a watershed. To derive a simple, general and analytical model of salinity distribution, we first make four hypotheses on the longitudinal salinity gradient based on empirical observations; we then derive a general unit hydrograph for the salinity distribution along a partially mixed or well-mixed estuary. The newly developed model can be well calibrated using a minimum of three salinity measurements along the estuary axis and does converge towards zero when the along-estuary distance approaches infinity asymptotically. The theory has been successfully applied to reproduce the salt intrusion in 21 estuaries worldwide, which suggests that the proposed method can be a useful tool for quickly assessing the spread of salinity under a wide range of riverine and tidal conditions and for quantifying the potential impacts of human-induced and natural changes.
- The genome and transcriptome of Japanese flounder provide insights into flatfish asymmetryPublication . Shao, Changwei; Bao, Baolong; Xie, Zhiyuan; Chen, Xinye; Li, Bo; Jia, Xiaodong; Yao, Qiulin; Orti, Guillermo; Li, Wenhui; Li, Xihong; Hamre, Kristin; Xu, Juan; Wang, Lei; Chen, Fangyuan; Tian, Yongsheng; Schreiber, Alex M.; Wang, Na; Wei, Fen; Zhang, Jilin; Dong, Zhongdian; Gao, Lei; Gai, Junwei; Sakamoto, Takashi; Mo, Sudong; Chen, Wenjun; Shi, Qiong; Li, Hui; Xiu, Yunji; Li, Yangzhen; Xu, Wenteng; Shi, Zhiyi; Zhang, Guojie; Power, Deborah M.; Wang, Qingyin; Schartl, Manfred; Chen, SonglinFlatfish have the most extreme asymmetric body morphology of vertebrates. During metamorphosis, one eye migrates to the contralateral side of the skull, and this migration is accompanied by extensive craniofacial transformations and simultaneous development of lopsided body pigmentation(1-5). The evolution of this developmental and physiological innovation remains enigmatic. Comparative genomics of two flatfish and transcriptomic analyses during metamorphosis point to a role for thyroid hormone and retinoic acid signaling, as well as phototransduction pathways. We demonstrate that retinoic acid is critical in establishing asymmetric pigmentation and, via cross-talk with thyroid hormones, in modulating eye migration. The unexpected expression of the visual opsins from the phototransduction pathway in the skin translates illumination differences and generates retinoic acid gradients that underlie the generation of asymmetry. Identifying the genetic underpinning of this unique developmental process answers long-standing questions about the evolutionary origin of asymmetry, but it also provides insight into the mechanisms that control body shape in vertebrates.