Climate Research | |
Surface conductance and energy exchange in an intensively managed peat pasture | |
A. Hensen1  B. O. M. Dirks1  | |
关键词: Aerodynamic technique; Surface conductance; Energy exchange; Latent heat; Sensible heat; Pasture; Grassland; | |
DOI : 10.3354/cr012029 | |
来源: Inter-Research Science Publishing | |
【 摘 要 】
ABSTRACT: Aerodynamic measurements of latent (λE) and sensible heat (H) exchange were made in an intensively managed peat pasture during 2 consecutive years; the fetch was approximately 1.5 km. The surfaceconductance (gs) was calculated from the Penman-Monteith equation. The analysis focused on 2 successive aspects of gs: gs as a function of environment (primarily vapour pressure deficit [D]) andthe energy balance as a function of gs. The effect of D on gs consisted of 2 components: the range of D over which gs was reduced (beyond inflection point Di) and thereducing effect per unit D. As average D increased, so did inflection point Di and the range of D over which gs was reduced; the reducing effect per unit D decreased. gs wasa strong mediator in the energy balance. λE increased with D upto the inflection point Di, beyond which gs increasingly offset the positive effect of D. Asgs impaired λE, the surface to air temperature difference (ΔT) and consequently H increased. With increasing gs,λE and H added up to progressively lower values, suggesting an increasing soil heat flux. Hysteresis in the diurnal patterns of the energy balance showed that the positive effect of D onλE remained stronger than the consequent negative effect of gs. λE was higher after than before noon, whereas ΔT and H were lower.
【 授权许可】
Unknown
【 预 览 】
Files | Size | Format | View |
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RO201912080705397ZK.pdf | 165KB | download |