Vulnerability of Eco-Hydrological Environment in the Yellow River Delta Wetland

Abstract

We investigated the relationship between groundwater head and oceanic tidal fluctuations in the Yellow River Delta wetland through on-site hydrological monitoring. Shallow groundwater heads were obviously affected by oceanic tide along the coastal zone. The ranges of the wetland zone can be readily assessed by measuring fluctuation amplitudes or lags. The results show that the influence radius is approximately 12 km to 18 km (when the correlation coefficient is 0.7 to 0.8) under the joint actions of oceanic tide and shallow groundwater seepage flow in clayey silt coastal wetland. A cross-sectional sketch of the coastal wetland model is developed based on monitoring data of groundwater and oceanic tidal fluctuations to study the vulnerability of the eco-hydrological environment in the Yellow River Delta wetland. The coastal wetland consists of three zones (the groundwater seepage zone, the tidal-induced transitional zone, and the tidal zone) with distinctly different hydraulic properties. Analytical solutions are used to estimate the vulnerability of the ecohydrological environment in the wetland aquifer located in the NE part of the Yellow River Delta wetland, Shandong Province, China. Our results show that changes in the shallow groundwater quality of the wetland are significantly affected by natural factors, such as strong cutoff in the lower reaches, storm tides, and human engineering activities. The northern coastal wetland may be submerged without damp proof when the height of a storm tide reaches 2.4 m. The depth of shallow groundwater and the salinity gradient are key factors that contribute to the vulnerability of the ecological environment. The vulnerability of the eco-hydrological environment is derived from the joint actions of groundwater dynamics, hydrochemistry, and tidal-induced processes under sedimentary stress and water pressure.

Variations of Hydrodynamics and Submarine Groundwater Discharge in the Yellow River Estuary Under the Influence of the Water-Sediment Regulation Scheme

“…Thus, large quantities of water are expected to be stored in the underlying aquifer (Moore 1999), and these paleo-channels may serve as potential pathways for discharging groundwater (Stieglitz 2005). Gao et al (2014) found that shallow groundwater heads are obviously affected by tides as far as 18 km inland from the Yellow River estuary, which also demonstrates the interactions between the subterranean estuary and the sea. The implementation of WSRS leads to a huge discharge of water, dissolved solids and sediment with a remarkable pulsed impact on the estuary.…”

An overview of ecohydrology of the Yellow River delta wetland

“…The hydrodynamics near Yellow River mouth is dominated by semidiurnal tides (tidal range around 1.5-2.0 m) and wind driven waves and residual currents (Bi et al, 2014). For the groundwater system of YRD, Gao et al (2014) divided coastal wetlands into groundwater seepage zone, tidal-induced transitional zone, and tidal zone, where the influence radius of oceanic tide is approximately 12-18 km. Integrated study on the interaction between freshwater inflow, sea water, and groundwater is urgently needed for the understanding of the hydrological processes of the YRD wetland.…”

“…Like many of the large deltas around the world (Blum and Roberts, 2009;Syvitski et al, 2009), the YRD is facing increasing risks of degradation due to anthropogenic and natural forces (Bi et al, 2014;Cui et al, 2009;Gao et al, 2014;Kong et al, 2015;Wang et al, 2007). The fundamental changes in land-building and land loss in the YRD plain are rooted in the supply of water and sediment from Yellow River that undergone major shifts in the river's course since the delta's formation in 1855.…”

Treat Phoenix River Water by Constructed Rapid Infiltration System

“…Combining with the actual situation of the local nature, social environment and economy, CRI system is chosen for water treatment in Phoenix River (Du, Xu, and Wang, 2009;Gao, Liu, and Zhao, 2014;Ma, Lu, and Wang, 2012;Xia, Wu, and Cao, 2009). Advantages of CRI system are: (1) Effect of wastewater treatment is better than that of the traditional activated sludge process.…”