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The water-sediment regulation scheme (WSRS), beginning in 2002, is an unprecedented engineering effort to manage the Yellow River with the aims to mitigate the siltation both in the lower river channel and within the Xiaolangdi Reservoir utilizing the dam-regulated flood water. Ten years after its initial implementation, multi-disciplinary indicators allow us to offer a comprehensive review of this human intervention on a river-coastal system. The WSRS generally achieved its objective, including bed erosion in the lower reaches with increasing capacity for flood discharge and the mitigation of reservoir siltation. However, the WSRS presented unexpected disturbances on the delta and coastal system. Increasing grain size of suspended sediment and decreasing suspended sediment concentration at the river mouth resulted in a regime shift of sediment transport patterns that enhanced the disequilibrium of the delta. The WSRS induced an impulse delivery of nutrients and pollutants within a short period (~ 20 days), which together with the altered hydrological cycle, impacted the estuarine and coastal ecosystem. We expect that the sediment yield from the loess region in the future will decrease due to soil-conservation practices, and the lower channel erosion will also decrease as the riverbed armors with coarser sediment. These, in combination with uncertain water discharge concomitant with climate change, increasing water demands and delta subsidence, will put the delta and coastal ocean at high environmental risks. In the context of global change, this work depicts a scenario of human impacts in the river basin that were transferred along the hydrological pathway to the coastal system and remotely transformed the different components of coastal environment. The synthesis review of the WSRS indicates that an integrated management of the river-coast continuum is crucially important for the sustainability of the entire river-delta system. The lessons learned from the WSRS in the Yellow River provide insights to the integrated management of large rivers worldwide. [ABSTRACT FROM AUTHOR]

The temporal variations of sea surface chlorophyll- a concentration off the Yellow River Mouth were investigated using SeaWiFS and MODIS data over the period of 1997–2012. And the complex interplay of different dominant factors (e.g. river inputs and coastal dynamics) on the phytoplankton dynamics in different seasons was discussed. High concentration of nutrients from the Yellow River inputs plays a significant role in sustaining phytoplankton growth. Approximately 59% of the interannual variations of the chlorophyll- a concentration off the Yellow River Mouth were attributed to river inputs (water discharge, sediment load and median grain size of sediment particles). On seasonal time scale, the Yellow River discharge of water and nutrients is a major factor that influences the increased chlorophyll- a concentration from August to October (summer and autumn). From February to May, the stronger winds and enhanced wave actions resuspend and vertically mix the previously deposited riverine sediment and the associated nutrient, thus possibly contributing to higher chlorophyll- a concentration. [ABSTRACT FROM AUTHOR]