Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands
In the highlands of northern Ethiopia, degraded hillslopes are closed for grazing and agriculture for environmental rehabilitation. In order to assess the effect of these exclosures on water balances, a correct assessment of evapotranspiration is needed. A common method for calculating evapotranspir...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
| Language: | Inglés |
| Published: |
Elsevier
2011
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10568/3037 |
| _version_ | 1855527305834659840 |
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| author | Descheemaeker, Katrien K. Raes, Dirk Allen, R. Nyssen, Jan Poesen, J. Muys, B. Haile, M. Deckers, J. |
| author_browse | Allen, R. Deckers, J. Descheemaeker, Katrien K. Haile, M. Muys, B. Nyssen, Jan Poesen, J. Raes, Dirk |
| author_facet | Descheemaeker, Katrien K. Raes, Dirk Allen, R. Nyssen, Jan Poesen, J. Muys, B. Haile, M. Deckers, J. |
| author_sort | Descheemaeker, Katrien K. |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | In the highlands of northern Ethiopia, degraded hillslopes are closed for grazing and agriculture for environmental rehabilitation. In order to assess the effect of these exclosures on water balances, a correct assessment of evapotranspiration is needed. A common method for calculating evapotranspiration employs the reference evapotranspiration in combination with a crop coefficient. However, for natural vegetation, these crop coefficients are not readily available. Therefore, the objective of this study was to derive crop coefficients for semiarid natural vegetation using two different approaches. The crop coefficients were assessed with the dual crop coefficient approach as outlined in the FAO Irrigation and Drainage Paper n°56 and compared with crop coefficients derived from a simple soil water balance. A good agreement between both methods was found. The mid-season crop coefficients ranged from 0.50 to 0.85 for open vegetation with small shrubs and from 0.85 to 0.95 for well developed shrubland. Vegetation with a closed tree canopy was characterized by a mid-season crop coefficient between 0.95 and 1.1. Additionally, a significant logarithmic relation between vegetative soil cover and crop coefficient was found. Using this relation, crop coefficients can be easily derived for semiarid shrub savannahs in similar environments and used for the calculation of evapotranspiration. |
| format | Journal Article |
| id | CGSpace3037 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2011 |
| publishDateRange | 2011 |
| publishDateSort | 2011 |
| publisher | Elsevier |
| publisherStr | Elsevier |
| record_format | dspace |
| spelling | CGSpace30372024-03-06T10:16:43Z Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands Descheemaeker, Katrien K. Raes, Dirk Allen, R. Nyssen, Jan Poesen, J. Muys, B. Haile, M. Deckers, J. crops water In the highlands of northern Ethiopia, degraded hillslopes are closed for grazing and agriculture for environmental rehabilitation. In order to assess the effect of these exclosures on water balances, a correct assessment of evapotranspiration is needed. A common method for calculating evapotranspiration employs the reference evapotranspiration in combination with a crop coefficient. However, for natural vegetation, these crop coefficients are not readily available. Therefore, the objective of this study was to derive crop coefficients for semiarid natural vegetation using two different approaches. The crop coefficients were assessed with the dual crop coefficient approach as outlined in the FAO Irrigation and Drainage Paper n°56 and compared with crop coefficients derived from a simple soil water balance. A good agreement between both methods was found. The mid-season crop coefficients ranged from 0.50 to 0.85 for open vegetation with small shrubs and from 0.85 to 0.95 for well developed shrubland. Vegetation with a closed tree canopy was characterized by a mid-season crop coefficient between 0.95 and 1.1. Additionally, a significant logarithmic relation between vegetative soil cover and crop coefficient was found. Using this relation, crop coefficients can be easily derived for semiarid shrub savannahs in similar environments and used for the calculation of evapotranspiration. 2011-04 2011-01-14T12:55:01Z 2011-01-14T12:55:01Z Journal Article https://hdl.handle.net/10568/3037 en Limited Access Elsevier Descheemaeker, K., Raes, D., Allen, R., Nyssen, J., Poesen, J., Muys, B., Haile, M. and Deckers, J. 2011. Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands. Journal of Arid Environments 75(4):353-359. |
| spellingShingle | crops water Descheemaeker, Katrien K. Raes, Dirk Allen, R. Nyssen, Jan Poesen, J. Muys, B. Haile, M. Deckers, J. Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands |
| title | Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands |
| title_full | Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands |
| title_fullStr | Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands |
| title_full_unstemmed | Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands |
| title_short | Two rapid appraisals of FAO-56 crop coefficients for semiarid natural vegetation of the northern Ethiopian highlands |
| title_sort | two rapid appraisals of fao 56 crop coefficients for semiarid natural vegetation of the northern ethiopian highlands |
| topic | crops water |
| url | https://hdl.handle.net/10568/3037 |
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