Research Theme: Planetary Metabolism
The complex web of biochemical and ecological processes that occur within the biosphere, and the interaction of these processes with the lithosphere, atmosphere and hydrosphere.
Why this Research Theme?
The sustainability of the biosphere in the face of rapid changes in the Earth system is an issue of critical importance. The physical and chemical features of the Earth are intimately tied to organisms and the activities required for their sustenance.
Both natural and anthropogenic disturbances drive the structure and dynamics of natural systems. A thorough understanding of these complex processes is essential for efforts to protect the biosphere from adverse effects due to pollution, destruction of natural landscapes, and climate change.
How We're Doing this Research
Research activities in planetary metabolism aim to quantify and locate the major biogeochemical cycles on global scales, investigate biosphere/atmosphere interactions at the biochemical level, identify the response of natural systems to perturbations (such as applications of pesticides), and study the influence of pollution on soil, air, and water.
Objective
The goal of work in the Planetary Metabolism theme is to improve our ability to observe, understand, predict and respond to changes in the global environment and to use this knowledge to protect the biosphere from the adverse effects of pollution, climate change, and alteration of natural environments.
Research
The sustainability of the biosphere during the current period of rapid changes in the Earth system is an issue of prime importance for the environmental sciences. The physical and chemical features of the Earth are intimately tied to organisms and the activities required for their sustenance. Both natural and anthropogenic disturbances drive the structure and dynamics of natural systems, and a thorough understanding of these complex processes is essential to efforts to protect the biosphere from adverse influences. Research within this theme focuses on biogeochemical cycling, biosphere-atmosphere interactions, the response of natural systems to perturbations, and transport and fate of chemicals in the biosphere.
Goals
- Increase our knowledge of the fundamental processes that drive the biosphere
- Use experimental tools to accurately measure indicators of change
- Carry out research that will develop science and technology to help restore and protect the health of the biosphere
- Enhance the sophistication of prognostic models capable of forecasting the response of ecosystems and the global biosphere to future environmental changes
Overview
The sustainability of the biosphere during the current period of rapid changes in the earth system is an issue of prime importance for the environmental sciences. The physical and chemical features of the earth are intimately tied to organisms and the activities required for their sustenance. The health of the biosphere can usefully be considered using the concept of "planetary metabolism", which refers to the complex web of biochemical and ecological processes that occur within the biosphere, and the interaction of these processes with the lithosphere, atmosphere and hydrosphere. Both natural and anthropogenic disturbances drive the structure and dynamics of natural systems, and a thorough understanding of these complex processes is essential for efforts to protect the biosphere from adverse effects due to pollution, destruction of natural landscapes, and alteration of climate. The following are the current areas of our primary focus.
Biogeochemical Cycling
Global networks of trace gas and stable isotope analysis, in combination with global circulation models, are currently being used to discern the global distribution of photosynthetic and respiratory sources and sinks. Inverse modeling approaches are enabling the partitioning of global carbon cycle components into oceanic and terrestrial components to identify more explicit latitudinal and longitudinal coordinate bands for particularly strong source and sink activity.
Biosphere-Atmosphere Interactions
Examples of specific studies include: an investigation of the reactivity of organic molecules in organic aerosols; quantifying carbon fluxes between the forest and the atmosphere; understanding the primary ecological controls over the rate and seasonal pattern of carbon sequestration; and studies on the ecological controls over methane emission from tropical wetland ecosystems that indicate methane emissions from tropical wetlands have probably been overestimated.
Response of Natural Systems to Perturbations
The response of natural systems to perturbations is being studied at scales ranging from the microbial to the global. Examples include: the evolution of metabolic pathways for degradation of pesticides in a soil bacterium that contributes to our knowledge of the ability of microorganisms to adapt to and degrade novel compounds in the environment; studies of regional and global land-use perturbations and their influence on biogeochemical cycles; studies of the factors controlling the deposition of oxidants and how such deposition affects primary productivity and ecosystem water use; and studies of perturbations in the nitrogen cycle of watersheds caused by increases in atmospheric deposition of nitrogen from anthropogenic sources.
Transport and Fate of Chemicals in the Biosphere
Example projects include: investigation of the fate of nitrogen oxide compounds emitted from temperate agricultural soils and tropical soils; studies of the uptake of atmospheric aerosols by various biological surfaces that will contribute to a fundamental understanding of how vegetated surfaces interact with the atmosphere through heterogeneous processes; and development of a new approach for estimating yields of nitrogen from continents to oceans under pre-industrial (background) conditions to be used as a benchmark against which human perturbations of the nitrogen cycle can be judged.
More Information
For more detailed information about planetary metabolism research at CIRES, contact Theme Leaders Shelley D. Copley, or see this full text description for research linkages and plans.
