The water regime of the Monegros playa-lakes as established from ground and satellite data

JOURNAL OF HYDROLOGY

卷:310

Article

Castañeda, C ; Herrero, J

关键词: playa-lake;    remote sensing;    irrigation;    flooding regime;    monegros;    Spain;   

DOI  :  10.1016/j.jhydrol.2004.12.007

来源: Elsevier

【 摘 要 】

The Monegros playa-lakes are isolated saline wetlands, locally named 'saladas situated in a vulnerable semi-arid territory where agricultural expansion threatens the natural hydrologic cycle with regular artificial flooding, risking the survival of a valuable natural resource. This study aims to examine the water regime of these playa-lakes from climate data and available hydrologic records. These records are historical and limited to a series of weekly measurements of depth and of water extent extracted from Landsat imagery. We have characterized the hydrological behavior of the playa-lakes by treating ground and satellite data separately. For this purpose, the playa-lakes are first grouped according to the water occurrence episodes. Then their hydrologic status is related to the previous rainfall and also to ETO, since there is a lack of local records of wind as well as brine or fresh water evaporation. The northern playa-lakes respond to rain faster than the southern ones. All playa-lakes have a significant relationship between water occurrence and rainfall accumulated within 180 days prior to an observation. A significant relationship between ETO and water occurrence was found for a shorter 15-day accumulation period. Quantifying the current water regime now is critical for monitoring the effects of expanding irrigation in adjacent lands. Remote sensing is well-suited to an environmental assessment for regions of difficult access with the added benefit of lowered field measurement cost. The hydrological data from the Monegros playa-lakes could be integrated with other playa environments worldwide to compare regionally specific climate conditions. (C) 2005 Elsevier B.V. All rights reserved.

【 授权许可】

Free