干旱区生态环境知识资源中心

We studied patterns and mechanisms controlling wind-driven flux of soils and associated organic matter in Taylor Valley, Antarctica over a 10-year period using passive aeolian traps and dynamic mass erosion particle counters. Deployment of the particle counters near meteorological stations allowed us to compare the magnitude of soil flux with data on prevailing wind. Particulate organic C, N and P measurements on transported sediment allowed us to examine connectivity of wind dispersed organic matter among landscape units. Most sediment entrainment occurred within 20 cm of the soil surface during "saltation bursts" that occupied <3% of the total time within a year. These bursts corresponded to periods of strong fohn winds where wind velocities were >= 20 m s(-1). Sediment movement was highest in the up-valley reaches of Taylor Valley and transport was down-valley towards McMurdo Sound. The general paucity of biological organic matter production throughout the McMurdo Dry Valleys, in concert with low fluvial transport, makes aeolian distribution or organic C. N and P an important factor in the distribution of organic matter throughout this polar desert ecosystem and increases connectivity among the ecosystem components. (C) 2011 Elsevier B.V. All rights reserved.