Depth-limiting resistant layers restrict dimensions and positions of estuarine channels and bars

Estuaries comprise channels vital for economic activity and bars as valuable habi tats. They are increasingly under human-induced pressures (e.g. sea-level rise and dredging), resulting in morphological changes that affect navigability, flood safety and ecology. Antecedent geology may strongly steer how estuary channels will adapt to these...

Sedimentary architecture and chronostratigraphy of a late Quaternary incised-valley fill: A case study of the late Middle and Late Pleistocene Rhine system in the Netherlands

This paper describes the sedimentary architecture, chronostratigraphy and palaeogeography of the late Middle and Late Pleistocene (Marine Isotope Stage/MIS 6-2) incised Rhine-valley fill in the central Netherlands based on six geological transects, luminescence dating, biostratigraphical data and a 3D geological model. The incised-valley fill...

Natural Environmental Changes versus Human Impact in a Florida Estuary (Rookery Bay, USA)

Assessing the impact of climate change and anthropogenic activity on Florida coastal areas requires a thorough understanding of natural climate variability. The available instrumental record, however, is too short and too limited to capture the full range of natural variability. In order to provide additional data on the natural state of the...

Development of a mid-Holocene estuarine basin, Rhine-Meuse mouth area, offshore The Netherlands

A proper understanding of coastal development during periods of rapid sea-level rise is a prerequisite for the prediction of future coastal response to the expected acceleration in sea-level rise. However, the development of back-barrier basins, especially in river-mouth areas, during such periods is still not well understood. Here we show the...

Late Holocene sea-level rise in Tampa Bay: Integrated reconstruction using biomarkers, pollen, organic-walled dinoflagellate cysts, and diatoms

A suite of organic geochemical, micropaleontological and palynological proxies was applied to sediments from Southwest Florida, to study the Holocene environmental changes associated with sea-level rise. Sediments were recovered from Hillsborough Bay, part of Tampa Bay, and studied using biomarkers, pollen, organic-walled dinoflagellate cysts...

Complex bounded rationality in dyke construction. Path-dependency, lock-in in the emergence of the geometry of the Zeeland delta

In this article the theoretical concepts of path-dependency and lock-in are applied to the geometry of the Zeeland delta in the Netherlands. They are used to show that even very small and unpredictable events can cause systems to remain on a path that is practically impossible to leave because the costs of leaving are too high. As a result,...

Facies architecture of heterolithic tidal deposits: The Holocene Holland Tidal Basin

The size, shape and spatial position of lithofacies types (or facies architecture) in a tidal estuarine basin are complex and therefore difficult to model. The tidal currents in the basin concentrate sand-sized sediment in a branching pattern of tidal channels and fringing tidal flats. Away from the sandy tidal flats the sediment gradually...

The Holocene evolution of the barrier and the back-barrier basins of Belgium and the Netherlands as a function of late Weichselian morphology, relative sea-level rise and sediment supply

Flooding of the southern part of the North Sea occurred between 9000 and 8000 BP, when the rate of relative sea-level rise was on the order of 0.7 cm per year for the Dover Strait Region and 1.6 cm per year for the area north of the Frisian Islands, forcing the shoreline to recede rapidly. When relative sea-level rise decelerated after 7000 BP...

Nitrous oxide emissions from estuarine intertidal sediments

From September 1990 through December 1991 nitrous oxide flux measurements were made at 9 intertidal mud flat sites in the Scheldt Estuary. Nitrous oxide release rates were highly variable both between sites and over time at any one site. Annual nitrous oxide fluxes vary from about 10 mmol N m-2 at the tidal fresh-water end-member site to almost...