Intertidal floodplain controls on centennial-scale morphological channel development

<p>Intertidal areas disappear in deltas worldwide because of land reclamations. This greatly impacts delta morphology because the presence and physiological characteristics of intertidal areas determine the tidal regime and, as a result, residual sediment transport patterns in tidal basins. Understanding how the interaction between intertidal areas and channels in tidal basins influence morphodynamics is therefore important to predict morphological development and to assess the resilience of delta’s to changing boundary conditions.</p><p>In the Ems estuary (The Netherlands), the gradual embankment of a large intertidal embayment altered the planform and cross-sectional geometry of the estuary, leading to changes in the tidal regime and associated residual sediment transport patterns. As early as 1952, it was already suggested that these changes eventually caused a shift towards an alternative historical development of the geometric configuration of the channels; from a multiple to a single channel system.</p><p>This study shows through centennial-scale morphological modelling that the observed system shift can be hind-casted, while conserving model validity by comparison to the observed gross morphodynamics trends. The results indicate that the system shift is indeed driven by land reclamations. This provides a unique case to study the processes leading to the observed developments and evaluate the value of tidal-asymmetry based stability relationships to predict regime shifts in estuarine development.</p>

Land Reclamations

This article deals with the hegemony of Anglo-Saxon social anthropology over the anthropologies of the South and its neighbour discipline, European ethnology. It departs from a description of my personal professional experience during the last thirty years to discuss how the disciplinary capacity of influence (and shadowing) is linked to political decisions, the definition of what is scientific, and the instrumental use of rankings and evaluations.

PROTECTING THE SHORELINE OF THE SAN FRANCISCO INTERNATIONAL AIRPORT FROM SEA LEVEL RISE

The San Francisco International Airport (SFIA) has approximately eight miles of shoreline along San Francisco Bay. It was built on a series of land reclamations constructed between 1927 and 1972. Primary consolidation and secondary settlement are still ongoing and expected to continue for 10 to 30 more years (M&N 2015). Figure 1 - SFIA Shoreline and Runways The length of shoreline makes SFIA susceptible to flooding. The flood risk is expected to increase with ongoing settlement and future sea level rise (SLR). A system of seawalls has been constructed along the perimeter to protect the airport from flooding. The shoreline along SFIA includes the end of Runway 1-19 and Runway 10-28, shown in Figure 1. Because the Federal Aviation Administration (FAA) requires that the end of runways be object-free areas (OFA), which prohibit seawalls from encroaching into the airspace and limits the allowable elevation, protection against future sea level rise (SLR) must be achieved without raising the seawalls. With SLR projections in San Francisco Bay of 1 foot by 2050 and 3 feet by 2100 (NRC 2012), SFIA decided to investigate alternative forms of flood protection at the end of the runways. Presented here is a feasibility study of alternative solutions.

The return of relatives: processes of mobilisation and village construction among the Tupinambá of Serra do Padeiro, southern Bahia, Brazil

The article examines land reclamations, actions of territorial recovery engaged in by the Tupinambá of the village of Serra do Padeiro, in southern Bahia, Brazil. It focuses on the return of relatives - i.e. the return of expropriated Indians as part of the reclamation process -, and seeks to examine the construction of the collective political subject that has engendered the reclamations, as it is engendered by them. The text presents a brief history of the process of territorialisation, indicating how the reclamations have become the group’s main form of political action. I argue that the process of land recovery is based on kinship, and is capable of activating latent ties or lead to the weakening or rupture of ties between relatives in opposing positions. I also propose that the reclamation process has extended the meaning of relative, providing nuance to the emphasis on blood and moving towards a definition of relative as those with whom you fight together.