کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4392979 | 1618249 | 2014 | 9 صفحه PDF | دانلود رایگان |
• Only 4326 out of 8404 playas ever contained water at least once 2008–2011.
• Hydroperiod was a function of precipitation and surrounding land use.
• Median hydroperiod was ∼109 days.
• Peak water availability differed by season and year.
• Urban land use extended playa hydroperiod whereas cropland decreased it.
We used remote sensing imagery to characterize the hydrological dynamics of 8404 temporary freshwater wetlands (playas) in Texas (Landsat 5 TM WRS-2 P30/R36) from 2008 to 2011, comparing known wet and dry periods, and related these to land use within 100 m. Hydroperiods were highly variable, and peak water availability occurred in different seasons in different years, varying by as much as two orders of magnitude with date. Land use affected the likelihood and duration of inundation, with playas in urban settings being modified in such a way as to extend hydroperiod, and playas surrounded by cropland experiencing shorter hydroperiods: 3726 playa basins never contained standing water during the four-year period, and many of these were surrounded by cotton, corn, wheat, or sorghum. In contrast, 25 playas never dried, and most of these were surrounded by urban development. Median hydroperiod was 17–109 days, being longer during the relatively wet year of 2010 compared to exceptional drought in 2011. Remote sensing was useful in monitoring playa surface water fluctuations as a function of land use, providing an alternative source of data in the absence of ground-based hydrological records, and granting a temporal perspective that may otherwise not exist for seasonal or ephemeral wetlands.
Journal: Journal of Arid Environments - Volume 109, October 2014, Pages 6–14