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42nd International Convention on Information and Communication Technology, Electronics and Microelectronics (MIPRO)

作者： Tolovski, Ilin Kostovska, Ana Simidjievski, Nikola Todorovski, Ljupco Dzeroski, Saso Panov, Pance Jozef Stefan Inst Dept Knowledge Technol Ljubljana Slovenia Jozef Stefan Int Postgrad Sch Ljubljana Slovenia Univ Cambridge Dept Comp Sci & Technol Cambridge England Univ Ljubljana Fac Adm Ljubljana Slovenia

ISBN: (纸本)9789532330984

Storing metadata about models of dynamical systems in a machine readable form is one of the key steps towards their accessibility and reusability. In the domain of process-based modeling of dynamical systems, the task is to construct an explanatory model of a dynamical system from domain knowledge and data. In this paper, we present a workflow for annotation, storage and querying of process-based models specifically in the domain of aquatic ecosystems. To provide the vocabulary of key terms about the process-based modeling paradigm, we use the Ontology for process-based modeling of Dynamical Systems (OntoPBM). Next, to capture the domain-specific characteristics, we extend OntoPBM with terms specific for aquatic ecosystems. The annotations for each process-based model are stored in an RDF triple store. This enables us to execute SPARQL queries on facts asserted in the annotations, as well as facts inferred from the domain knowledge encoded in the ontology. Finally, by following the proposed workflow, we generate the minimal information about a model, which takes us one step closer towards reusable research.

关键词： dynamical systems process-based modeling ontologies knowledge representation querying reusability

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Investigating old-growth ponderosa pine physiology using tree-rings, δ¹³C, δ¹⁸O, and a process-based model

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ECOLOGY 2019年第6期100卷 e02656-e02656页

作者： Ulrich, Danielle E. M. Still, Christopher Brooks, J. Renee Kim, Youngil Meinzer, Frederick C. Los Alamos Natl Lab Biosci Div POB 1663 MS M888 Los Alamos NM 87545 USA Oregon State Univ Dept Forest Ecosyst & Soc Corvallis OR 97331 USA US EPA NHEERL Western Ecol Div Corvallis OR 97331 USA US Forest Serv USDA Pacific Northwest Res Stn Corvallis OR 97331 USA

In dealing with predicted changes in environmental conditions outside those experienced today, forest managers and researchers rely on process-based models to inform physiological processes and predict future forest growth responses. The carbon and oxygen isotope ratios of tree-ring cellulose (delta C-13(cell), delta O-18(cell)) reveal long-term, integrated physiological responses to environmental conditions. We incorporated a submodel of delta O-18(cell) into the widely used Physiological Principles in Predicting Growth (3-PG) model for the first time, to complement a recently added delta C-13(cell) submodel. We parameterized the model using previously reported stand characteristics and long-term trajectories of tree-ring growth, delta C-13(cell), and delta O-18(cell) collected from the Metolius AmeriFlux site in central Oregon (upland trees). We then applied the parameterized model to a nearby set of riparian trees to investigate the physiological drivers of differences in observed basal area increment (BAI) and delta C-13(cell) trajectories between upland and riparian trees. The model showed that greater available soil water and maximum canopy conductance likely explain the greater observed BAI and lower delta C-13(cell) of riparian trees. Unexpectedly, both observed and simulated delta O-18(cell) trajectories did not differ between the upland and riparian trees, likely due to similar delta O-18 of source water isotope composition. The delta O-18(cell) submodel with a Peclet effect improved model estimates of delta O-18(cell) because its calculation utilizes 3-PG growth and allocation processes. Because simulated stand-level transpiration (E) is used in the delta O-18 submodel, aspects of leaf-level anatomy such as the effective path length for transport of water from the xylem to the sites of evaporation could be estimated.

关键词： carbon isotope ratios effective path length oxygen isotope ratios Physiological Principles in Predicting Growth process-based modeling tree rings

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Coupling of remote sensing, field campaign, and mechanistic and empirical modeling to monitor spatiotemporal carbon dynamics of a Mediterranean watershed in a changing regional climate

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ENVIRONMENTAL MONITORING AND ASSESSMENT 2015年第4期187卷 1页

作者： Berberoglu, S. Donmez, C. Evrendilek, F. Cukurova Univ Div Remote Sensing & GIS Dept Landscape Architecture Adana Turkey Abant Izzet Baysal Univ Dept Environm Engn Bolu Turkey

The aim of this study was to simulate impacts of regional climate change in the 2070s on carbon (C) cycle of a Mediterranean watershed combining field measurements, Envisat MERIS and IKONOS data, and the Carnegie Ames Stanford Approach model. Simulation results indicated that the present total C sink status (1.36 Mt C year(-1)) of Mediterranean evergreen needleleaf forest, grassland and cropland ecosystems is expected to weaken by 7.6 % in response to the climate change in the 2070s (Mt=10(12) g). This decreasing trend was mirrored in soil respiration (R-H), aboveground and belowground net primary production (NPP), NEP, and net biome production (NBP). The decrease in NEP in the 2070s was the highest (21.9 %) for mixed forest where the smallest present C sink of 0.03 Mt C year(-1) was estimated. The average present net ecosystem production (NEP) values were estimated at 110 +/- 15, 75 +/- 19, and 41 +/- 25 g C m(-2) years(-1) in forest, grassland, and cropland, respectively, with a watershed-scale mean of 95 +/- 30 g C m(-2) years(-1). The largest present C sink was in grassland, with a total C pool of 0.55 Mt C year(-1), through its greater spatial extent.

关键词： Carbon sink Global climate change Mediterranean ecosystems process-based modeling Spatiotemporal dynamics

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WEHY-HCM for modeling Interactive Atmospheric-Hydrologic processes at Watershed Scale. I: Model Description

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JOURNAL OF HYDROLOGIC ENGINEERING 2013年第10期18卷 1262-1271页

作者： Kavvas, M. L. Kure, S. Chen, Z. Q. Ohara, N. Jang, S. Univ Calif Davis Dept Civil & Environm Engn Hydrol Res Lab Davis CA 95616 USA Calif Dept Water Resources Sacramento CA 95814 USA

Among the key problems in atmospheric and hydrologic sciences are the modeling of the interaction between the atmosphere and land surface hydrology while also quantifying the surface/subsurface hydrologic flow processes both in vertical and lateral directions, and modeling the heterogeneity in surface and subsurface hydrologic processes. Meanwhile, in standard water resources engineering practice, the planning and management of the water resources is performed over the geographical region of a watershed. To address these issues, a model of coupled atmospheric-hydrologic processes at the watershed scale, the Watershed Environmental Hydrology Hydro-Climate Model (WEHY-HCM), has been developed. The atmospheric model PSU/NCAR MM5 (Fifth Generation Mesoscale Model) was coupled to the watershed hydrology model WEHY through the atmospheric boundary layer to form the WEHY-HCM. The WEHY-HCM is especially useful for producing nonexistent atmospheric data as input to the modeling of surface and subsurface hydrologic processes at sparsely gauged or ungauged watersheds. The continuously changing state of the atmospheric boundary layer may be essential information in the computation of evapotranspiration (ET) rates and other land surface fluxes. Because such land surface fluxes are the result of the interaction of land surface hydrologic processes with atmospheric processes, their realistic estimation necessitates the coupled modeling of these processes, as is done in the WEHY-HCM. The model is also useful at watersheds that have heterogeneous topography and land use/cover because the main model components are based on areally averaged, scalable conservation equations and parameters in order to quantify and account for the effect of heterogeneity within watersheds. In this paper, the modeling of an integrated system of atmospheric processes aloft coupled with atmospheric boundary layer processes, land surface processes, and surface and subsurface hydrologic processes is described

关键词： Watersheds Hydrologic models Watershed Environmental Hydrology Hydro-Climate model Dynamical downscaling process-based modeling

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The influence of parameter fitting methods on model structure selection in automated modeling of aquatic ecosystems

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ECOLOGICAL MODELLING 2012年 245卷 136-165页

作者： Cerepnalkoski, Darko Taskova, Katerina Todorovski, Ljupco Atanasova, Natasa Dzeroski, Saso Jozef Stefan Inst Dept Knowledge Technol Ljubljana Slovenia Jozef Stefan Inst Comp Syst Dept Ljubljana Slovenia Jozef Stefan Int Postgrad Sch Ljubljana Slovenia Ctr Excellence Integrated Approaches Chem & Biol Ljubljana Slovenia Univ Ljubljana Fac Adm Ljubljana Slovenia Univ Algarve Ctr Marine & Environm Res CIMA Faro Portugal Int Ctr Coastal Ecohydrol Faro Portugal

modeling dynamical systems involves two subtasks: structure identification and parameter estimation. ProBMoT is a tool for automated modeling of dynamical systems that addresses both tasks simultaneously. It takes into account domain knowledge formalized as templates for components of the process-based models: entities and processes. Taking a conceptual model of the system, the library of domain knowledge, and measurements of a particular dynamical system, it identifies both the structure and numerical parameters of the appropriate process-based model. ProBMoT has two main components corresponding to the two subtasks of modeling. The first component is concerned with generating candidate model structures that adhere to the conceptual model specified as input. The second subsystem uses the measured data to find suitable values for the constant parameters of a given model by using parameter estimation methods. ProBMoT uses model error to rank model structures and select the one that fits measured data best. In this paper, we investigate the influence of the selection of the parameter estimation methods on the structure identification. We consider one local (derivative-based) and one global (meta-heuristic) parameter estimation method. As opposed to other comparative studies of parameter estimation methods that focus on identifying parameters of a single model structure, we compare the parameter estimation methods in the context of repetitive parameter estimation for a number of candidate model structures. The results confirm the superiority of the global optimization methods over the local ones in the context of structure identification. (C) 2012 Elsevier B.V. All rights reserved.

关键词： Aquatic ecosystems Dynamical systems Equation discovery process-based modeling Parameter estimation Meta-heuristic optimization

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Past-century decline in forest regeneration potential across a latitudinal and elevational gradient in Canada

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ECOLOGICAL MODELLING 2015年 313卷 94-102页

作者： Erickson, Adam Nitschke, Craig Coops, Nicholas Cumming, Steven Stenhouse, Gordon Univ British Columbia Dept Forest Resources Management Integrated Remote Sensing Studio Vancouver BC V6T 1Z4 Canada Univ Melbourne Sch Ecosyst & Forest Sci Richmond Vic 3121 Australia Univ Laval Dept Wood & Forest Sci Quebec City PQ G1V 0A6 Canada Foothills Res Inst Hinton AB T7V 1X6 Canada

The regeneration niche of trees greatly narrows the fundamental niche and is sensitive to climatic change. Development from seed and phenology are regulated by biological and environmental controls, shaping forest successional pathways. We hypothesized that recent climate change is reducing regeneration suitability in northern forests. We used a process-based ecophysiological model to examine changes in forest regeneration conditions across an elevational and latitudinal gradient in Alberta, Canada from 1923 to 2012. We compared these results to a recent empirical study in the region to infer the recent drivers of regeneration change in northern forests. Our results suggest that these forests are experiencing climatically driven declines in conditions suitable for regeneration. Contrary to previous findings indicating poorer current conditions in low elevation forests, we found more stable regeneration potential there, attributable to a relative abundance of soil moisture. Rocky soils resulted in modeled losses of soil moisture at higher elevations, potentially preventing upslope migrations of species despite warming. We identify potential mechanisms driving unexpected tree regeneration patterns described in previous studies. Our simulations suggest a delayed response of forest regeneration to warming throughout the past 90 years. (C) 2015 Elsevier B.V. All rights reserved.

关键词： process-based modeling Tree regeneration Species distribution modeling Phenology Climate change Soil water balance

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Does centennial morphodynamic evolution lead to higher channel efficiency in San Pablo Bay, California?

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MARINE GEOLOGY 2013年 345卷 254-265页

作者： van der Wegen, M. Jaffe, B. E. UNESCO IHE NL-2601 DA Delft Netherlands USGS USGS Pacific Coastal & Marine Sci Ctr Santa Cruz CA 95060 USA

Measured bathymetries on 30 year interval over the past 150 years show that San Pablo Bay experienced periods of considerable deposition followed by periods of net erosion. However, the main channel in San Pablo Bay has continuously narrowed. The underlying mechanisms and consequences of this tidal channel evolution are not well understood. The central question of this study is whether tidal channels evolve towards a geometry that leads to more efficient hydraulic conveyance and sediment throughput. We applied a hydrodynamic process-based, numerical model (Delft3D), which was run on 5 San Pablo Bay bathymetries measured between 1856 and 1983. Model results shows increasing energy dissipation levels for lower water flows leading to an approximately 15% lower efficiency in 1983 compared to 1856. During the same period the relative seaward sediment throughput through the San Pablo Bay main channel increased by 10%. A probable explanation is that San Pablo Bay is still affected by the excessive historic sediment supply. Sea level rise and Delta surface water area variations over 150 years have limited effect on the model results. With expected lower sediment concentrations in the watershed and less impact of wind waves due to erosion of the shallow flats, it is possible that energy dissipations levels will decrease again in future decades. Our study suggests that the morphodynamic adaptation time scale to excessive variations in sediment supply to estuaries may be on the order of centuries. (C) 2013 Elsevier B.V. All rights reserved.

关键词： estuarine geomorphology process-based modeling energy dissipation tidal channel evolution

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The influence of sea level rise and changes in fringing reef morphology on gradients in alongshore sediment transport

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GEOPHYSICAL RESEARCH LETTERS 2013年第12期40卷 3096-3101页

作者： Grady, A. E. Moore, L. J. Storlazzi, C. D. Elias, E. Reidenbach, M. A. Univ Virginia Dept Environm Sci Charlottesville VA 22904 USA Univ N Carolina Dept Geol Sci Chapel Hill NC USA US Geol Survey Santa Cruz CA USA Deltares Delft Netherlands

[1] Climate-change-induced alterations to coral reef ecosystems, in combination with sea level rise, have the potential to significantly alter wave dissipation across reefs, leading to shifts in alongshore sediment transport gradients and alterations to tropical coastlines. We used Delft3D to model schematized profiles of two reef flat widths based on the south Molokai, Hawaii coast. Simulated anthropogenic modifications include incremental degradation of the reef structure as well as sea level rise. Our findings indicate that sea level rise has a greater relative effect on wave energy flux and alongshore sediment transport over a wide flat, whereas both reef degradation and sea level rise exert similar influence over a narrow flat. These results suggest reefs that vary in width alongshore are more likely to experience changes in alongshore sediment transport gradients, and therefore shifts in shoreline erosion and accretion patterns, than more uniform reef systems.

关键词： coastal change coral reefs sediment transport process-based modeling

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Adaptive forest management improves stand-level resilience of temperate forests under multiple stressors

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SCIENCE OF THE TOTAL ENVIRONMENT 2024年 948卷 174168页

作者： Guignabert, Arthur Jonard, Mathieu Messier, Christian Andre, Frederic de Coligny, Francois Doyon, Frederik Ponette, Quentin Catholic Univ Louvain Earth & Life Inst Louvain La Neuve Belgium Univ Quebec Montreal Ctr Etud Foret Montreal PQ Canada Univ Quebec Outaouais Inst Sci Foret Temperee Ripon PQ Canada Univ Montpellier AMAP CIRAD CNRSIRDINRAE Montpellier France

Forests are expected to be strongly affected by modifications in climate and disturbance regimes, threatening their ability to sustain the provision of essential services. Promoting drought-tolerant species or functionally diverse stands have recently emerged as management options to cope with global change. Our study aimed at evaluating the impact of contrasting stand-level management scenarios on the resilience of temperate forests in eastern North America and central-western Europe using the individual process-based model HETEROFOR. We simulated the evolution of eight stands over 100 years under a future extreme climate according to four management scenarios (business as usual- BAU;climate change adaptation- CC;functional diversity approach- FD;no management- NM) while facing multiple disturbances, resulting in a total of 160 simulations. We found that FD demonstrated the greatest resilience regarding transpiration and tree biomass, followed by CC and then BAU, while these three scenarios were equivalent concerning the net primary production. These results were however dependent on forest type: increasing functional diversity was a powerful option to increase the resilience of coniferous plantations whereas no clear differences between BAU and adaptive management scenarios were detected in broadleaved and mixed stands. The FD promoted a higher level of tree species diversity than any other scenario, and all scenarios of management were similar regarding the amount of harvested wood. The NM always showed the lowest resilience, demonstrating that forest management could be an important tool to mitigate adverse effects of global change. Our study highlighted that tree-level process-based models are a relevant tool to identify suitable management options for adapting forests to global change provided that model limitations are considered, and that alternative management options, particularly those based on functional diversity, are promising and should be promoted fr

关键词： Adaptive forest management Disturbances Functional diversity Forest resilience process-based modeling Temperate forests

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Short- and long-term responses of total soil organic carbon to harvesting in a northern hardwood forest

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FOREST ECOLOGY AND MANAGEMENT 2010年第7期259卷 1262-1267页

作者： Johnson, Kristofer Scatena, Frederick N. Pan, Yude Univ Penn Dept Earth & Environm Sci Philadelphia PA 19104 USA US Forest Serv No Res Stn USDA Newtown Sq PA 19073 USA

The long-term response of total soil organic carbon pools ('total SOC', i.e. soil and dead wood) to different harvesting scenarios in even-aged northern hardwood forest stands was evaluated using two soil carbon models, CENTURY and YASSO, that were calibrated with forest plot empirical data in the Green Mountains of Vermont. Overall, 13 different harvesting scenarios that included four levels of aboveground biomass removal (20%, 40%, 60% and 90%) and four different rotation lengths (60 year, 90 year, 120 year, and No Rotation (NR)) were simulated for a 360 year period. Simulations indicate that following an initial post-harvest increase, total SOC decreases for several decades until carbon inputs into the soil pool from the re-growth are greater than losses due to decomposition. At this point total SOC begins to gradually increase until the next harvest. One consequence of this recovery pattern is that between harvests, the size of the SOC pool in a stand may change from -7 to 18% of the pre-harvest pool, depending on the soil pool considered. Over 360 years, the average annual decrease in total SOC depends on the amount of biomass removed, the rotation length, and the soil pool considered. After 360 years a stand undergoing the 90yr-40% scenario will have 15% less total SOC than a non-harvested stand. Longterm declines in total SOC greater than 10% were observed in the 60yr-60%, 60yr-90%, and 90yr-90% scenarios. Long-term declines less than 5% were observed in scenarios with 120 year rotations that remove 60% or less of the aboveground biomass. The long-term decreases simulated here for common management scenarios in this region would require intensive sampling procedures to be detectable. (C) 2009 Elsevier B.V. All rights reserved.

关键词： Northern hardwood forest Soil carbon modeling process-based modeling Forest soil carbon

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