新时期黄河治理几个关键问题探讨OA

The flow and sediment regimes of the Yellow River have undergone a fundamental shift.The basin's long-standing characteristic of"low flow with high sediment load"has now given way to a persistent condition better described as"low flow with low sediment"—a reality that no longer aligns with the planning framework and flood-operation strategies established under previous assumptions.This paper argues that as the Yellow River Basin moves toward high-quality development in the coming period,its governance faces five pressing challenges:a)Current flood-design parameters deviate from actual conditions,resulting in an oversized flood-control layout.b)Despite a sharp decline in incoming sediment to the reservoir,the operation of Sanmenxia Reservoir remains unchanged,which unduly marginalizes its functional po-tential.c)While the main channel of the Lower Yellow River continues to incise,the"suspended river"above the surrounding ground re-mains an enduring threat.d)The bottleneck constraint of the river narrows in the lower reach is prominent,making it difficult to liberate the flood detention and storage zones under relatively conservative design flood conditions.e)The vast number of check dams built across the middle and upper reaches have played a substantial role in trapping sediment,yet many are prone to breaching and pose considerable ecologi-cal concerns.In response to these key issues,this study proposes a set of targeted,actionable measures:First,revise the existing flood-de-sign criteria and the annual average sediment load entering the lower reaches,so that the downstream flood-mitigation system can be placed on a more rational footing.Second,optimize the coordinated operation of Sanmenxia and Xiaolangdi Reservoirs to more fully tap the value of Sanmenxia Reservoir.Third,promote community-based hydraulic sand-dredging for riverbed lowering—an approach that requires limited state investment and could potentially transform the suspended river into a below-grade channel.Fourth,physically widen the Aishan narrows to re-move a critical bottleneck and reverse the passive defensive posture in the lower reaches.Fifth,scale up the application of new check-dam construction and reinforcement technologies that fundamentally alter the seepage-failure mode of conventional designs,thereby ensuring struc-tural integrity and safety.