Barchan dunes emerge as a collective phenomena involving the generation of thousands of them in so called barchan dune fields. By measuring the size and position of dunes in Moroccan barchan dune fields, we find that these dunes tend to distribute uniformly in space and follow an unique size distribution function. We introduce an analytical mean-field approach to show that this empirical size d...

In this work, we present measurements of the height profile, wind velocity and sand flux performed on transverse dunes in the dune field known as “Lençóis Maranhenses”, northeastern Brazil. From the measured profile, we selected one dune to measure the air shear stress and the sand flux and compared the results with the theoretical predictions from a dune model in two dimensions recently introd...

The Mars Science Laboratory rover Curiosity visited two active wind-blown sand dunes within Gale crater, Mars, which provided the first ground-based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial-like and uniquely Martian processes. The prese...

A series of pyroclastic density currents were generated at Tungurahua volcano (Ecuador) during a period of heightened activity in August 2006. Dense pyroclastic flows were confined to valleys of the drainage network, while dilute pyroclastic density currents overflowed on interfluves where they deposited isolated bodies comprising dune bedforms of cross-stratified ash exposed on the surface. He...

The megathrust earthquake of moment magnitude 9.1 – 9.3 on December 26, 2004 unleashed a massive tsunami which devastated the coastal belts of Sri Lanka as well as several other countries bordering the Indian Ocean. Extensive field observations carried out in Sri Lanka in the aftermath of the tsunami clearly showed that the spatial variation of the degree of destruction along the coastal belt w...

Preservation and effective management of highly dynamic coastal features located in areas under development pressures requires in-depth understanding of their evolution. Modern geospatial technologies such as lidar, real time kinematic GPS, and three-dimensional GIS provide tools for efficient acquisition of high resolution data, geospatial analysis, feature extraction, and quantification of ch...

The impact of an exotic species in natural systems may be dependent not only on invader attributes but also on characteristics of the invaded community. We examined impacts of the invader bitou bush, Chrysanthemoides monilifera ssp. rotundata , in fore and hind dune communities of coastal New South Wales, Australia. We compared invader impacts on vegetation structure, richness of both native an...

The sand dunes and inter-dune zones of the hyper-arid central Namib Desert represent heterogeneous soil habitats. As little is known about their indigenous edaphic bacterial communities, we aimed to evaluate their diversity and factors of assembly and hypothesized that soil physicochemistry gradients would strongly shape dune/interdune communities. We sampled a total of 125 samples from 5 paral...

0019-1035/$ see front matter 2011 Elsevier Inc. A doi:10.1016/j.icarus.2011.01.005 ⇑ Corresponding author. Fax: +33 4 72 44 85 93. E-mail address: [email protected] (E. Ga High albedo features are identified in association with barchan dunes in an equatorial inter-crater dune field on Mars using images from the MRO mission. This paper describes the morphometric properties of these fea...

Low lying coastal areas have always been attractive for people to live, but are also prone to flooding. In The Netherlands, half of the population lives in the coastal area below mean sea level where two-thirds of the economic value is located. Coastal dunes protect the hinterland from flooding as a primary sea defence along the major part of the Dutch coastline. The envisaged protection level ...