نتایج جستجو برای: aeolian landforms
تعداد نتایج: 3280 فیلتر نتایج به سال:
Drylands are characterised by patchy vegetation, erodible surfaces and erosive aeolian processes. Empirical and modelling studies have shown that vegetation elements provide drag on the overlying airflow, thus affecting wind velocity profiles and altering erosive dynamics on desert surfaces. However, these dynamics are significantly complicated by a variety of factors, including turbulence, and...
[1] Hydrological and aeolian processes redistribute sediments and nutrients within arid landscapes with important effects on the composition and structure of vegetation. Despite the relevance of wind and water erosion to the dynamics of arid and semiarid ecosystems, the interactions between these two processes remain poorly understood. In this paper we present the results of an intensive set of...
We reveal that the transition in the saturated flux for aeolian saltation is generically discontinuous by explicitly simulating particle motion in turbulent flow in two dimensions. The discontinuity is followed by a coexistence interval with two metastable solutions. We found also that the mere presence of mid-air collisions, surprisingly, enhances the saturated flux, which has a peak for an in...
This study focuses on linear anthropogenic landforms of decametric width on cultivated hillslopes and their relations to soil thickness variability. The 16 ha study area shows a rolling topography supported by Cretaceous chalk of the SW Parisian Basin, France. Two types of landforms were identified: lynchets, similar to those described as soil terraces occurring on downslope field parts in othe...
Plants in the desert may locally change the aeolian process, and hence the pattern of sand ripples traveling nearby. The effect of plants on ripples is investigated using a coupled map lattice model with nonuniform coupling coefficients.
The landscape of the study area (fig. 1,2) is underlain by coversand, deposited during the Late Glacial of the Weichselian. In the Preboreal, aeolian processes reduced soil formation (Stichting voor Bodemkaratering, 1972) and from the Preboreal to the Atlantic a deciduous climax forest developed (Janssen, 1974). The geomorphology was a coversand landscape, composed of ridges (umbric podzols), c...
Introduction: The number of currently available images of the surface of Mars is in the order of the hundreds of thousands. These have been captured over the years by many different instruments on board automatic probes. They have diverse spectral characteristics, varying spatial resolutions and cover areas of different dimensions, providing global, regional and sometimes local views. To manual...
[1] Aeolian dust input may be a critical source of dissolved iron for phytoplankton growth in some oceanic regions. We used an atmospheric general circulation model (GCM) to simulate dust transport and removal by dry and wet deposition. Model results show extremely low dust concentrations over the equatorial Pacific and Southern Ocean. We find that wet deposition through precipitation scavengin...
Desertification is a worldwide concern and the assessment of aeolian desertification has become one hotspot in global ecosystem research. In this paper, hyperspectral data acquired from modular OMIS-I imaging spectrometer, combined with ETM data and field survey data, was used to assess the aeolian desertification in Korqin Sand, Inner Mongolia, China by pixel-level. The results indicated that ...
The general flow structure over transverse aeolian dunes is now well documented through both field studies and wind tunnel experiments. Research on windward (stoss) slopes of dunes is extensive and has recently been complemented by research on the lee-side flow structure. However, a number of technical deficiencies in wind tunnel instrumentation and a lack of detailed resolution in and appropri...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید