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| Titel |
SIGNAL : Water vapour flux variability and local wind field investigations within five differently managed agroforestry sites across Germany |
| VerfasserIn |
Christian Markwitz, Lukas Siebicke, Alexander Knohl |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250135998
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| Publikation (Nr.) |
 EGU/EGU2016-16936.pdf |
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| Zusammenfassung |
| Optimising soil water uptake and ground water consumption in mono-specific agricultural
systems plays an important role for sustainable land management. By including tree alleys
into the agricultural landscape, called agroforestry (AF), the wind flow is modified leading to
a presumably favourable microclimate behind the tree alleys. We expect that this zone is
characterized by increased air temperature and atmospheric water vapour content, compared
to mono-specific fields. This would extend the growing season and increase the yield
production behind the tree alleys.
Within the SIGNAL (Sustainable Intensification of Agriculture through Agroforestry)
project the evapotranspiration (ET) variability and the local wind field of agroforestry sites
compared to mono-specific agricultural systems is investigated. Our study is based on the
comparison of five differently managed agroforestry sites across Germany. All site feature
one agroforestry plot and one reference plot, which represents a mono-specific cropped
system. Each plot is equipped with an eddy-covariance tower, including a high frequency 3D
SONIC anemometer and instruments gathering standard meteorological parameter as
pressure, temperature, relative humidity, precipitation, ground heat flux, net- and global
radiation.
The Surface Energy Budget (SEB) method will be used to calculate evapotranspiration
QE as
QE = − QN − QH − QG − Res
by measuring the sensible heat flux, QH, with the eddy covariance method, the radiation
balance, QN and the ground heat flux, QG. QH and QN will be measured continuously
long-term. We will quantify site specific energy balance non-closure, Res, by temporarily
measuring QE, using eddy covariance and a roving tower and then solving the SEB equation
for Res. The short term Res will be used to then continuously derive QE from the SEB
method.
We will compare measured evapotranspiration rates from the SEB method to modelled
evapotranspiration of the agroforestry systems through upscaling of an one dimensional two
layer SVAT model of the Shuttleworth and Wallace type to the agroforestry system. Finally,
the evapotranspiration, calculated by the SEB method and modelled with the SVAT model
will be used as an input to the LES model ASAM (All Scale Atmospheric Model) to
simulate the three dimensional wind field around the complex agroforestry system. |
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