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- Camino-Serrano, Marta, et al.
(författare)
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ORCHIDEE-SOM : Modeling soil organic carbon (SOC) and dissolved organic carbon (DOC) dynamics along vertical soil profiles in Europe
- 2018
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Ingår i: Geoscientific Model Development. - : Copernicus GmbH. - 1991-959X .- 1991-9603. ; 11:3, s. 937-957
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Tidskriftsartikel (refereegranskat)abstract
- Current Land Surface Models (LSMs) typically represent soils in a very simplistic way, assuming soil organic carbon (SOC) as a bulk, thus impeding a correct representation of deep soil carbon dynamics. Moreover, LSMs generally neglect the production and export of dissolved organic carbon (DOC) from soils to rivers, leading to overestimations of the potential carbon sequestration on land. These common oversimplified processing of SOC in LSMs is partly responsible for the large uncertainty in the predictions of the soil carbon response to climate change. In this study, we present a new soil carbon module called ORCHIDEE-SOM, embedded within the land surface model ORCHIDEE, which is able to reproduce the DOC and SOC dynamics in a vertically discretized soil to two meters. The model includes processes of biological production and consumption of SOC and DOC, DOC adsorption on- and desorption from soil minerals, diffusion of SOC and DOC and DOC transport with water through and out of the soils to rivers. We evaluated ORCHIDEE-SOM against observations of DOC concentrations and SOC stocks from four European sites with different vegetation covers: a coniferous forest, a deciduous forest, a grassland and a cropland. The model was able to reproduce the SOC stocks along their vertical profiles at the four sites and the DOC concentrations within the range of measurements, with the exception of the DOC concentrations in the upper soil horizon at the coniferous forest. However, the model was not able to fully capture the temporal dynamics of DOC concentrations. Further model improvements should focus on a plant- and depth- dependent parameterization of the new input model parameters, such as the decomposition times of DOC and the microbial carbon use efficiency. We suggest that this new soil module, when parameterized for global simulations, will improve the representation of the global carbon cycle in LSMs, thus helping to constrain the predictions of the future SOC response to global warming.
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| 2. |
- Filieri, Antonio, et al.
(författare)
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Automated Design of Self-Adaptive Software with Control-Theoretical Formal Guarantees
- 2015
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Ingår i: Software Engineering and Management 2015 : Multikonferenz der GI-Fachbereiche Softwaretechnik (SWT) und Wirtschaftsinformatik (WI), FA WI-MAW - Multikonferenz der GI-Fachbereiche Softwaretechnik (SWT) und Wirtschaftsinformatik (WI), FA WI-MAW. - 1617-5468. - 9783885796336 ; P-239, s. 112-113
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Konferensbidrag (refereegranskat)abstract
- Self-adaptation enables software to execute successfully in dynamic, unpredictable, and uncertain environments. However, most of the current approaches lack formal guarantees on the effectiveness and dependability of the adaptation mechanisms, limiting their applicability in practice. Control theory established a broad set of mathematically grounded techniques for the control of dynamic systems for several engineering fields. While control shares self-evident similarities with software adaptation, modeling software behavior as a system of differential or difference equations is not straightforward, nor is mastering the mathematical background needed for synthesizing a suitable controller. In this paper we focus on the automatic modeling and controller synthesis for systems with a single knob affecting the satisfaction of a quantitative requirements. Effectiveness and performance of the controller are guaranteed by construction. The approach is fully automated and implemented in several programming languages, empowering non-experts with the ability of applying control principles to a wide range of software adaptation problems.
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