globalchange  > 气候变化事实与影响
DOI: 10.5194/hess-20-2063-2016
Scopus记录号: 2-s2.0-84971441382
论文题名:
Dominant controls of transpiration along a hillslope transect inferred from ecohydrological measurements and thermodynamic limits
作者: Renner M; , Hassler S; K; , Blume T; , Weiler M; , Hildebrandt A; , Guderle M; , Schymanski S; J; , Kleidon A
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2016
卷: 20, 期:5
起始页码: 2063
结束页码: 2083
语种: 英语
Scopus关键词: Atmospheric movements ; Budget control ; Forestry ; Moisture ; Plants (botany) ; Soil moisture ; Soils ; Solar radiation ; Transpiration ; Wind ; Absorbed solar radiations ; Absorption of solar radiation ; European beech (fagus sylvatica l.) ; Forest transpirations ; Heterogeneous conditions ; Independent measurement ; Surface energy budget ; Vapor pressure deficit ; Soil surveys ; absorption ; complex terrain ; deciduous tree ; diurnal variation ; ecohydrology ; energy budget ; forest inventory ; hillslope ; net ecosystem exchange ; sap flow ; soil moisture ; solar radiation ; stand dynamics ; stand structure ; surface energy ; thermodynamics ; transpiration ; vapor pressure ; water uptake ; wind velocity ; Luxembourg [Benelux] ; Luxembourg [Luxembourg (NTN)] ; Fagus sylvatica
英文摘要: We combine ecohydrological observations of sap flow and soil moisture with thermodynamically constrained estimates of atmospheric evaporative demand to infer the dominant controls of forest transpiration in complex terrain. We hypothesize that daily variations in transpiration are dominated by variations in atmospheric demand, while site-specific controls, including limiting soil moisture, act on longer timescales.

We test these hypotheses with data of a measurement setup consisting of five sites along a valley cross section in Luxembourg. Both hillslopes are covered by forest dominated by European beech (Fagus sylvatica L.). Two independent measurements are used to estimate stand transpiration: (i) sap flow and (ii) diurnal variations in soil moisture, which were used to estimate the daily root water uptake. Atmospheric evaporative demand is estimated through thermodynamically constrained evaporation, which only requires absorbed solar radiation and temperature as input data without any empirical parameters. Both transpiration estimates are strongly correlated to atmospheric demand at the daily timescale. We find that neither vapor pressure deficit nor wind speed add to the explained variance, supporting the idea that they are dependent variables on land-atmosphere exchange and the surface energy budget. Estimated stand transpiration was in a similar range at the north-facing and the south-facing hillslopes despite the different aspect and the largely different stand composition. We identified an inverse relationship between sap flux density and the site-average sapwood area per tree as estimated by the site forest inventories. This suggests that tree hydraulic adaptation can compensate for heterogeneous conditions. However, during dry summer periods differences in topographic factors and stand structure can cause spatially variable transpiration rates. We conclude that absorption of solar radiation at the surface forms a dominant control for turbulent heat and mass exchange and that vegetation across the hillslope adjusts to this constraint at the tree and stand level. These findings should help to improve the description of land-surface-atmosphere exchange at regional scales. © Author(s) 2016.
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78835
Appears in Collections:气候变化事实与影响

Files in This Item:

There are no files associated with this item.


作者单位: Max-Planck-Institut für Biogeochemie, Jena, Germany; GFZ German Research Centre for Geosciences, Section Hydrology, Potsdam, Germany; Universität Freiburg, Hydrologie, Freiburg, Germany; Universität Jena, Ecological Modelling Group, Jena, Germany; ETH Zürich, Department of Environmental Systems Science, Zurich, Switzerland; Karlsruhe Institute of Technology, Institute of Water and River Basin Management, Karlsruhe, Germany; Technische Universität München, Department of Ecology and Ecosystemmanagement, Munich, Germany

Recommended Citation:
Renner M,, Hassler S,K,et al. Dominant controls of transpiration along a hillslope transect inferred from ecohydrological measurements and thermodynamic limits[J]. Hydrology and Earth System Sciences,2016-01-01,20(5)
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Renner M]'s Articles
[, Hassler S]'s Articles
[K]'s Articles
百度学术
Similar articles in Baidu Scholar
[Renner M]'s Articles
[, Hassler S]'s Articles
[K]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Renner M]‘s Articles
[, Hassler S]‘s Articles
[K]‘s Articles
Related Copyright Policies
Null
收藏/分享
所有评论 (0)
暂无评论
 

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.