 |
| Titel |
Assessment of waterlogging in agricultural megaprojects in the closed drainage basins of the Western Desert of Egypt |
| VerfasserIn |
M. Bastawesy, R. Ramadan Ali, A. Faid, M. Osta |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 17, no. 4 ; Nr. 17, no. 4 (2013-04-18), S.1493-1501 |
| Datensatznummer |
250018852
|
| Publikation (Nr.) |
 copernicus.org/hess-17-1493-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| This paper investigates the development of waterlogging in the cultivated
and arable areas within typical dryland closed drainage basins (e.g. the
Farafra and Baharia Oases), which are located in the Western Desert of
Egypt. Multi-temporal remote sensing data of the Landsat Thematic Mapper
(TM) and Enhanced Thematic Mapper (ETM+) were collected and processed to
detect the land cover changes; cultivations, and the extent of water ponds
and seepage channels. The Shuttle Radar Topography Mission (SRTM) digital
elevation model (DEM) has been processed to delineate the catchment
morphometrical parameters (i.e. drainage networks, catchment divides and
surface areas of different basins) and to examine the spatial distribution
of cultivated fields and their relation to the extracted drainage networks.
The soil of these closed drainage basins is mainly shallow and lithic with
high calcium carbonate content; therefore, the downward percolation of excess
irrigation water is limited by the development of subsurface hardpan, which
also saturates the upper layer of soil with water. The subsurface seepage
from the newly cultivated areas in the Farafra Oasis has revealed the
pattern of buried alluvial channels, which are waterlogged and outlined by
the growth of diagnostic saline shrubs. Furthermore, the courses of these
waterlogged channels are coinciding with their counterparts of the SRTM DEM,
and the recent satellite images show that the surface playas in the
downstream of these channels are partially occupied by water ponds. On the
other hand, a large water pond has occupied the main playa and submerged the
surrounding fields, as a large area has been cultivated within a relatively
small closed drainage basin in the Baharia Oasis. The geomorphology of
closed drainage basins has to be considered when planning for a new
cultivation in dryland catchments to better control waterlogging hazards. The
"dry-drainage" concept can be implemented as the drainage and seepage water
can be conveyed through the inactive alluvial channels into certain
abandoned playas for evaporation. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|