SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...
SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...
SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...
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Chapter 7 General discussion and conclusions<br />
3. After the long-term exclosure (~ 25 yr), grassland soils showed distinct signs<br />
of recovery from grazing-caused damages in hydraulic as well as mechanical<br />
aspects.<br />
4. The temporal stability concept, linked with a hydraulic model, provided a<br />
useful tool for sampling strategies and verifications of hydraulic process.<br />
5. The modified hydraulic model HYDRUS was successful in simulating the<br />
coupled transport of water and heat in the investigated rangeland ecosystems.<br />
The model results showed that intense grazing deteriorated soil functions,<br />
consequently reduced the plant available water and thus grassland productivity.<br />
6. An extended freezing model is validated with measured data, which provide a<br />
basis for simulations of snow hydrology and soil freezing and thawing<br />
processes.<br />
Outlook<br />
It is still a challenge to estimate fluxes at different spatial scales. Especially, how<br />
hydraulic model, e.g. HYDRUS-1D/2D can be applied to a large area, e.g. Xinlin<br />
River catchment where the MAGIM project took place with the knowledge of<br />
scaling (regionalization, transferability and upscaling).<br />
The monitoring (e.g. soil hydraulic properties, water content) in the deep soil<br />
must be determined not only for water use efficiency considering water use by<br />
roots deep penetrating into deeper soil layers (e.g. hydraulic lift) but also for the<br />
verification of model.<br />
Improvement of bo<strong>und</strong>ary conditions, respectively, an assessment of regional<br />
heterogeneity of rainfall is vital for model validations.<br />
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