Terrestrial Systems Ecology: Research
Present Research Activities and Research Perspectives
Prime focus of Terrestrial Systems Ecology research is on:
- Behavior of terrestrial ecosystems in a changing climate (modeling and
simulation) with emphasis on mountainous forest ecosystems
- Relationships between biophysical forcing factors and ecosystem functions
- Systems theory of ecological systems
In the recent years the Systems Ecology' research group emphasized the
following three aspects:
- Issues: Climate Change impact on ecosystems (e.g. agroecosystems, forests),
mitigation of green-house-gas emmissions (e.g. in forestry), and
sustainable utilization of natural resources via Adaptive Environmental
Assessment and Management (AEAM).
- Models and Theories: Development of state-of-the-art ecosystem models
(e.g. ForClim)
and
development of a systems theory of ecosystems (theoretical systems ecology)
based on standard formalisms such as
DESS (Differential Equation System Specification),
SQM (Sequential Machines or simply Automata)
and
DEVS (Discrete EVent system Specification)
- Tools: Interactive modeling and simulation tools such as
RAMSES
(Research Aids for Modeling and Simulation of Environmental Systems),
which includes e.g.
Modelworks
(interactive modeling and simulation environment for PCs and workstations),
ISIS
(Integrative Systems Implementation Software),
or
RASS
(the RAMSES Simulation Server).
Our research forms also part of the following national and international research programmes:
- OPTICONTROL
- Optimal Control of
heating in buildings to save energy by profiting from latest
developments in weather forecasts and control theory - a
collaborative effort by the ETH Zurich, EMPA DŸbendorf, MeteoSwiss
and Siemens Building Technologies
- NFP48
- National Research Programme NRP48: Landscapes and Habitats of the Alps
- Nationales Forschungsprogramm NFP48: Landschaften und Lebensräume der Alpen
- NCCR Climate
(Climate Variability, Predictability and Climate Risks)
- NCCR - The National Centers of Competence in Research are managed by the
Swiss National Science Foundation
on behalf of the federal authorities
- Contribution of Forests and Forestry to Mitigate Greenhouse Effects - COST E21
- COST - European Cooperation in the field of Scientific and Technical Research
Behavior of terrestrial ecosystems in a changing climate
ForClimSense
Purpose: Furthering our understanding of the sensitivities of forest
ecosystems in the Alps to climatic change and the associated uncertainties.
Approach: The dynamic forest patch-model ForClim has been developed
to assess the impact of future climatic changes on forests, particularly
in the alpine region. It simulates successional patterns in forest ecosystems
by simulating explicitly all abiotic, i.e. mainly climatic, factors. Currently ForClim
is validated in past climatic change scenarios using various proxy data
such as isotopes and pollen records for a time window covering the end of
the last ice age. Results: Simulations at selected test sites revealed a
large spectrum of forest responses to the same changes in the climatic
input, which range from primary successional growth to complete
die-backs. Perspectives: The core of the current project is a systematic
analysis of the sensitivity of species compositions to local climate
change scenarios and the related uncertainties (see project ÒCase Studies
in Bioclimatic Scenario DerivationÓ). Furthermore the cohort based
stochastic model ForClim is aggregated to a structured population
dynamics model. The latter will be used to describe tree species
migration in a complex topography forced by a changing climate.
ForAgroClim
Purpose: Modeling the carbon-dynamics in forest ecosystems under
the influence of climatic change.
Approach: The carbon fluxes exerted by a terrestrial ecosystem
play a major role as biospheric feed-backs in the climatic system. The
forest gap-model ForClim provides a basis to simulate the elemental fluxes
of C and N. Given the importance of carbon, both in the context of the
global carbon cycle and as a key element in ecosystem functioning via
coupling with nutrients, ForClim is presently refined to include the major
fluxes driving the C-cycle. Results: Soil-borne processes and soil
organic carbon in particular have been recognized as major components of
the carbon balance of forests. Parameters were identified and the
structure of the soil carbon submodel has been improved. Perspectives:
Integration of the soil submodel into the larger ForClim. Parametric
sensitivity analysis. Validation of the new ForClim variant and model
applications to assess quantitatively impacts of climatic change on boreal
and temperate forests.
Bioclimatic Scenario Derivation
The project is aimed at developing, testing, and applying methods to derive
future climate scenarios as required by specific ecosystem case studies in
a mountainous region. Statistical ÒdownscalingÓ techniques are developed to
empirically link regional climatic changes to global climate variations, and
then applied to estimate possible future shifts in regional climates from
simulations with General Circulation Climate Models (GCMs). Stochastic
time series models and weather generators are used to describe climate and
weather variability at different time scales. Interpolation techniques are
developed to estimate base-line climate and climatic changes at any location
of interest. In close collaboration with ecosystem modelers, the resulting
application-specific bioclimatic scenarios are applied to study the sensitivities
of ecosystem models, and to assess possible future ecosystem responses in
the European Alps.
RAMSES - Methodology of computer-assisted Research Aids for Modeling
and Simulation of Environmental Systems
Based on the modeling and systems theory by Wymore (1984) and Zeigler
(1976, 1984) we work on the theoretical basis and the needed mathematical
formalisms to model and simulate ill-defined systems, which are often
studied in environmental sciences in various contexts. Workstation-aided
structureda, modular modeling and interactive simulation require software
tools, to support an efficient and scientifically rigorous mathematical
modeling and analysis of complex systems.
Curent implementations of RAMSES tools are embedded in flexible system
architectures to support not only text-book but real research needs typically
arising in ecological modeling projects. Case studies (see other projects)
allow to test the validity of the tools in supporting earlier as well as later
phases of research. In earlier phases the emphasis is typically on the
support of a flexible model development which can only be provided by an
open, yet robust system architecture; in later phases the focus shifts to
extensive simulation experiments such as sensitivity analysis, parameter
identification, or optimal systems control. The current focus is on simulation
servers (RASS) running within a local area network and supporting the batch
execution of distributed simulation experiments of model definition programs
originally developed only for an interactive environment.
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Terrestrial Systems Ecology
Institute of Terrestrial Ecology (ITÖ)
Department of Environmental Sciences
ETHZ
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Last modified 21/09/2007
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