The greatest change in particle roundness, sphericity, and size in most fluvial systems generally occurs in the initial first few kilometers of sediment transport. Observations in natural settings and laboratory experiments have shown that changes, such as increased gi'ain rounding and decreased size due to particle breakage, wear, and attrition, tend to be progz'essive along the dispersal path...

Freshwater biodiversity is declining faster than terrestrial and marine biodiversity. The protection restoration of aquatic habitats are based, in part, on stemming this decline. We conducted a spatial conservation assessment native fishes the Lahontan central Nevada basins using core-area zonation. complementarity-based yielded landscape value (rank) all subwatersheds (12-digit hydrologic unit...

Variational Methods have been frequently used for surface reconstruction and contour extraction (snakes). We present a surface reconstruction method where we assume the surface composed of two regions of di erent types of smoothness. One region of the surface models a \lake" (constant height region with uphill borders). It is surrounded by the other background region which is reconstructed usin...

During the Last Glaciation in Tasmania a large ice cap developed on the western edge of the Central Plateau and overlapped on to the Cradle Mountain-Lake St Clair area. Several reticulate lobes flowed from this source, with the largest northern outlet, the Mersey Glacier, covering an area of c. 282 km2• The Lake Ayr Valley was occupied by a smail diffiuent lobe of the Mersey Glacier, and the la...

Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still ...

A continuous record of lacustrine sedimentation capturing the entire full-glacial period was obtained from Arolik Lake in the Ahklun Mountains, southwestern Alaska. Fluctuations in magnetic susceptibility (MS), grain size, organic-matter (OM) content, C/N ratios, C, and biogenic silica (BSi) record marked environmental changes within the lake and its watershed during the last 33 cal ka. Age con...