@techreport{HuettlKoegelKnabnerSchulinetal.2013, author = {H{\"u}ttl, Reinhard F. and K{\"o}gel-Knabner, Ingrid and Schulin, Rainer and Gerwin, Werner}, title = {Structures and processes of the initial ecosystem development phase in an artificial water catchment (Final report CRC/TR 38)}, organization = {BTU Cottbus}, issn = {1867-7800}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus-28658}, year = {2013}, abstract = {Objective of the Transregional Collaborative Research Centre (CRC/TR) 38 was the study of structures and processes of the initial ecosystem development. It was assumed that the initial phase is characterized by less structured and therefore less heterogeneous ecosystems. Thus, analysis of young ecosystems in their initial stages should provide better insights into ecosystem functioning. Following this basic concept, the idea of the CRC/TR 38 was to analyze the establishment of new structures and processes which lead to a growing structuring and in consequence to a growing complexity and heterogeneity in an artificially created watershed. Further, with the help of this step-by-step development of the ecosystem it was aimed to learn from occurring feedbacks, which appear between old and newly emerging structures and patterns in order to better understand also the behavior of more mature systems. Special emphasis was placed on the spatial and temporal dynamics of both evolving structures and related processes and their interactions. In summary, the CRC/TR 38 was able to identify a number of structures and processes that are considered to be relevant and specific for young systems.}, subject = {Welzow; Braunkohlentagebau; Rekultivierung; Wasserherkunftsgebiet; {\"O}kosystem; {\"O}kosystem; {\"O}kologie; Bodenkunde; Hydrologie; Limnologie; Ecosystem; Ecology; Soil science; Hydrology; Freshwater science}, language = {en} } @phdthesis{He2020, author = {He, Qianwen}, title = {Evaluating the effect of multi-objective calibration on the modeling of catchment-scale hydrology and nitrogen load}, doi = {10.26127/BTUOpen-5233}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-52330}, school = {BTU Cottbus - Senftenberg}, year = {2020}, abstract = {Process-based hydrological models, which simulate nitrogen load from its sources to the receiving waterbody, play an important role in supporting catchment management. The reliability of those models, such as the representative model SWAT used in this study, is determined by a sound calibration and the analysis of the prediction uncertainty. The multi-objective calibration approach prevails the classic single-objective calibration on the spatial parameterization of specific processes. However, the requirement of additional observations and practical procedures limits its application. Moreover, the prediction uncertainty of nitrogen load is inevitable and should also be quantified. This study is a scientific contribution to catchment management by overcoming the challenge with a systematic, well-founded concept of multi-objective calibration and uncertainty analysis for nitrogen load simulation in data-scarce catchments. The concept is tested and proofed by its practical applicability on the Yuan River Catchment (YRC) in China and leads to a generalized, recommended procedure for catchment management application as valuable progress in this field. The study proposed to apply three groups of objectives, multi-site, multi-objective-function, and multi-metric. The applicability and the advantages of two multi-objective calibration approaches, Euclidean Distance and Non-Dominated Sorting Genetic Algorithm-II were analyzed. To quantify the prediction uncertainty, the study proposed to use the simulations with the highest or the lowest percent bias to represent the uncertainty band of the nitrogen load from the critical source areas (CSAs) and to the stream. The data-scarcity of the YRC was overcome by metrics obtained from open-access satellite-based datasets and metrics extracted from the existing discharge observations. Results show that multi-objective calibration has ensured the model's better performance in terms of the spatial parameterization, the magnitude of the output time-series and the water balance components, in comparison to single-objective calibration. The predicted CSAs showed that 50\% of the total nitrogen (TN) loading to the stream was from 26.3\% to 37.1\% of the area in the YRC. Meanwhile, over 50\% of those TN were from the paddy field. Recommendations for application go to the multi-objective calibration considering all three groups of objectives. Approaches to obtain multi-metric objectives in the YRC are also applicable for catchments with data-scarcity. Recommendations for nitrogen management in the YRC is to emphasize the CSAs identified, especially the paddy field.}, subject = {Multi-objective calibration; Prediction uncertainty; Hydrological modeling; Catchment with data-scarcity; Nitrogen load simulation; Multikriterielle Kalibrierung; Vorhersageunsicherheit; Hydrologische Modellierung; Datenarme Einzugsgebiete; Simulation der Stickstoffbelastung; Roter Fluss; Mathematische Modellierung; SWAT< Software>; Wasserherkunftsgebiet; Stickstoffbelastung; Mehrkriterielle Optimierung}, language = {en} }