I. Estuaries are regarded as valuable nursery habitats for many commercially important marine fishes. Recruitment of fish from estuarine nursery habitats to adult marine populations is considered important for maintenance of fishable stocks, but most evidence for this is qualitative. Effective and timely implementation of estuarine conservation and fisheries management plans may be aided by qua...

Despite suggestions that extensive mixing and large-scale transport of organic matter occurs within estuarine systems and across fluvial-estuarine-coastal ecotones (Teal 1962, Odum 1980), more recent evidence in estuarine detritus-based food web systems has shown strong gradients in the sources of organic matter assimilated by consumers across diverse fluvial-estuarine-coastal ocean scales (Pet...

The temporal response of the length of a partially-mixed estuary to changes in freshwater discharge, Qf , and tidal amplitude, UT , is studied using a 108 day time series collected along the length of the Hudson River estuary in the spring and summer of 2004 and a long-term (13.4 year) record of Qf , UT , and near-surface salinity. When Qf was moderately high, the tidally-averaged length of the...

A series of dye releases in the Hudson River estuary elucidated diapycnal mixing rates and temporal variability over tidal and fortnightly time scales. Dye was injected in the bottom boundary layer for each of four releases during different phases of the tide and of the spring–neap cycle. Diapycnal mixing occurs primarily through entrainment that is driven by shear production in the bottom boun...

We used the dual isotopic composition of nitrate (d15N and d18O) within the estuarine system of San Francisco (SF) Bay, California, to explore the utility of this approach for tracing sources and cycling of nitrate (NO 3 ). Surface water samples from 49 sites within the estuary were sampled during July–August 2004. Spatial variability in the isotopic composition suggests that there are multiple...

Lithium isotopes in marine authigenic or detrital sedimentary archives have been recently used to trace continental weathering over geologic timescales. However, interpretations are predominantly based on the assumption that riverine Li isotopic signals can be propagated through estuaries without modification. Here, we verify this hypothesis by investigating behaviour of Changjiang (Yangtze) Ri...

The adjustment of estuarine circulation and density to changes in river flow and tidal mixing is investigated using analytical and numerical models. Tidally averaged momentum and salinity equations in a rectangular estuary are vertically averaged over two levels, resulting in equations that are analytically tractable while retaining a broad range of time-dependent behavior. It is found that bot...

In coastal regions, age-0 juveniles of many fish species are capable of recruiting to either marine or estuarine nursery habitats, yet the ecological consequences for cohorts that use marine versus estuarine nurseries is poorly understood. In the present study, stable isotope (δ13C, δ15N) and stomach contents data were used to compare trophic ecology associated with differential habitat use for...

Motivated by field studies of the Ems estuary which show longitudinal gradients in bottom sediment concentration as high as O(0.01 kg/m), we develop an analytical model for estuarine residual circulation based on currents from salinity gradients, turbidity gradients, and freshwater discharge. Salinity is assumed to be vertically well mixed, while the vertical concentration profile is assumed to...