 |
| Titel |
The dependence of water potential in shoots of Picea abies on air and soil water status |
| VerfasserIn |
A. Sellin |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 16, no. 4 ; Nr. 16, no. 4, S.470-476 |
| Datensatznummer |
250013248
|
| Publikation (Nr.) |
 copernicus.org/angeo-16-470-1998.pdf |
|
|
|
|
|
| Zusammenfassung |
Where there is sufficient water storage in
the soil the water potential (Ψx) in shoots of
Norway spruce [Picea abies (L.) Karst.] is strongly governed by the
vapour pressure deficit of the atmosphere, while the mean minimum values of
Ψx usually do not drop below –1.5 MPa under
meteorological conditions in Estonia. If the base water potential (Ψb)
is above –0.62 MPa, the principal factor causing water deficiency in shoots of P.
abies may be either limited soil water reserves or atmospheric evaporative
demand depending on the current level of the vapour pressure deficit. As the
soil dries the stomatal control becomes more efficient in preventing water
losses from the foliage, and the leaf water status, in turn, less sensitive to
atmospheric demand. Under drought conditions, if Ψb
falls below –0.62 MPa, the trees' water stress is mainly caused by low soil
water availability. Further declines in the shoot water potential (below –1.5
MPa) can be attributed primarily to further decreases in the soil water, i.e. to
the static water stress.
Key words. Hydrology (evapotranspiration · plant
ecology · soil moisture). |
| |
|
| Teil von |
|
|
|
|
|
|
|
|