|
Titre :
|
Estimation of soil heat flux from net radiation during the growth of alfalfa
|
|
Auteurs :
|
B. Clothier ;
K. Clawson ;
U.S. DEPARTMENT OF AGRICULTURE PHOENIX AGRICULTURAL RESEARCH SERVICE ;
P. Pinter ;
U.S. WATER CONSERVATION LABORATORY PHOENIX ;
M. Moran ;
R. Reginato ;
R. Jackson
|
|
Type de document :
|
article/chapitre/communication
|
|
Année de publication :
|
1986
|
|
Format :
|
p. 319-329
|
|
Langues:
|
= Anglais
|
|
Catégories :
|
AGRICULTURE, AGRONOMIE ET ELEVAGE
|
|
Mots-clés:
|
LUZERNE
;
RECOLTE
;
TRANSFERT DE CHALEUR
;
CROISSANCE VEGETALE
;
HUMIDITE DU SOL
;
COUVERT VEGETAL
;
RAYONNEMENT SOLAIRE
;
INDICE DE VEGETATION
|
|
Résumé :
|
Soil heat flux studies have indicated that the instantaneous daytime flux can be estimated as a fraction of the net radiation, the ratio ranging from 0.1 to 0.5, depending on the amount of vegetation present and on the time of day. Soil heat flux and net radiation were measured for an alfalfa crop over two regrowth cycles during the fall growing season. For both sparse alfalfa stubble and full vegetative canopy, the surface soil water content did not significantly affect the fraction of net radiation consumed as soil heat flux. The results indicate that both crop height and spectral vegetation indices can be used to estimate soil heat flux from net radiation measurements.
|
|
Source :
|
Agricultural and forest meteorology, vol. 37
|
