 |
| Titel |
Simple, spatial and predictive approach for cereal yield prediction in the
semi-arid areas |
| VerfasserIn |
Jihad Toumi, Said Khabba, Salah Er-Raki, Michel Le Page, Aicha Chahbi Bellakanji, Zohra Lili Chabaane, Jamal Ezzahar, Mehrez Zribi, Lionel Jarlan |
| Konferenz |
EGU General Assembly 2016
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250128935
|
| Publikation (Nr.) |
 EGU/EGU2016-8982.pdf |
|
|
|
|
|
| Zusammenfassung |
| The objective is to develop a simple, spatial and predictive approach of dry matter (DM) and
grain yield (GY) of cereal in the semi-arid areas. The proposed method is based on the three
efficiencies model of Monteith (1972). This approach summarizes the transformation of solar
radiation to the dry matter (DM) by the climate (ɛc), interception (ɛi) and conversion (ɛconv)
efficiencies. The method combines the maximum of ɛi and ɛconv (noted ɛimax and ɛconvmax)
into a single parameter denoted ɛmax, calculating as a function of cumulating growing degree
day (CGDD). Also, the stress coefficient ks, which affects the conversion of solar
radiation to the biomass was calculated by the surface temperature or the water
balance at the root zone. In addition, the expression of ks has been improved by the
consideration of the results achieved by deficit irrigation (AquaCrop and STICS models)
which showed that the value of ks from 0.7 to 1 didn’t affect significantly the cereal
production. For the partitioning of the dry matter developed, between straw and grain,
the method proposed calculates a variable Harvest Index coefficient (HI). HI is
deducted from CGDD and HI0max (maximal final harvest Index in the region of study).
Finally, the approach calculates DM depending Satellite Information (NDVI and
surface temperature Ts) and climatic data (solar radiation and air temperature). In
the case of no availability of Ts, the amount of irrigation is required to calculate
ks.
Until now, the developed model has been calibrated and validated on the irrigated area
R3, located 40 Km east of Marrakech. The evolutions of DM and GY were reproduced
satisfactorily. R2 and RMSE are respectively 0.98 and 0.35 t/ha and 0.98 and 0.19 t/ha,
respectively. Currently, additional tests are in progress on data relating to the Kairouan plain
of Tunisia. |
|
|
|
|
|
|