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Submitted to: Physical Geography
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/12/2000 Publication Date: 10/23/2003 Citation: Stout, J. E. 2003. Seasonal variations of saltation activity on a High Plains saline Playa: Yellow Lake, Texas. Physical Geography 24(1):61-76. Interpretive Summary: Within the last century, most of the native grassland vegetation on the Southern High Plains has been converted to an extensive patchwork of crop- land and there is little doubt that the shift from grassland to cultivated fields has contributed significantly to the frequent dust storms that blow across the region. Because agricultural dust sources far outnumber natural lsources, little attention has been paid to the latter. There are, however natural dust sources on the Southern High Plains that are large enough to influence local and possibly regional ambient air quality. In terms of surface area, the numerous saline playas are among the largest natural dust sources in the region and they have been observed to emit plumes that extend large distances downwind of the playa surface. This report is based upon a two-year investigation of blowing dust at Yellow Lake, a saline playa located in the Yellow House Basin northwest of Lubbock, Texas. Results indicate that dust emissions peak during winter when winds are strong and dry conditions prevail and, despite strong spring winds, the playa is stable during spring when rainfall is more plentiful. This contrasts sharply with the surrounding agricultural lands which tend to be most active during spring. Technical Abstract: Spaced across the vast and otherwise featureless Southern High Plains are 21 large closed basins containing approximately 40 irregularly shaped saline playas. Yellow Lake, located on the Yellow House Ranch west of Anton, Texas, is among the largest of the high plains saline playas. Maximum water depth rarely exceeds 50 cm and it occasionally dries out completely for extended periods. Normally, surface waters form a broad shallow pool that occupies a limited fraction of the playa surface. The portion of the playa surface not wetted by the shallow pool is susceptible to aeolian deflation. This paper represents the first report of a two-year study of saltation activity at Yellow Lake using fast-response piezoelectric saltation sensors. Since saltation activity is often associated with dust emissions, the saltation record also provides information regarding seasonal patterns of dust emissions from the Yellow House Basin. The results indicate that saltation activity and dust emissions peak during winter when winds are moderately strong and precipitation is at a minimum and the playa is stable during spring when precipitation is more plentiful. This contrasts sharply with the surrounding agricultural lands which tend to be most active during spring. |
