How Does Life Begin and Develop?
Objective
1
Sources of 0rganics on Earth
Objective
2
Origin of Life's Cellular Components
Objective
4
Genomic Clues to Evolution
Objective
5
Linking Planetary and Biological Evolution
Does Life Exist Elsewhere in the Universe?
Objective
7
The Extremes of Life
Objective
8
Past and Present Life on Mars
Objective
9
Life's Precursors and Habitats in the Outer Solar System
Objective
10
Natural Migration of Life
Objective
11
Origin of Habitable Planets
Objective
12
Effects of Climate and Geology on Habitability
Objective
13
Extrasolar Biomarkers
What is Life's Future on Earth
and Beyond?
Objective
14
Ecosystem Response to Rapid Environmental Change
Objective
15
Earth's Future Habitability
Objective
16
Bringing Life with Us beyond Earth
Objective
17
Planetary Protection
Question:
What is Life's Future on Earth and Beyond?
Ecosystem
Response to Rapid Environmental Change
Objective 14: Determine the resilience of local and global ecosystems through their response to natural and human-induced disturbances.
The ability of a planet to support the long-term existence of life depends upon life's ability to withstand changes in its environment from a variety of causes. Throughout its history, life on Earth has experienced such changes with events ranging from impacts of asteroids and comets-- and their resultant global manifestations -- to ice ages of varying duration. Throughout each of these changes, life generally has responded initially with reductions in genetic diversity, followed by recoveries and continued increases in biodiversity. The current possibilities for major impact of human activities on the terrestrial biosphere (such as the depletion of stratospheric ozone) constitute an excellent observational laboratory to test the vulnerability of ecosystems, both large and small, to environmental changes with timescales commensurate with those of human culture. Studies of such ecosystem response to rapid environmental changes will help extend ecosystem models on the Earth and to other worlds, allow predictions of responses to major, planet-wide changes, and identify limits to these changes beyond which life may not be able to recover.
Implementation
Near to Mid-Term:
- Determine the critical biophysical
and geochemical components and process interactions during the reformation
of terrestrial ecosystems, by conducting field campaigns to sites where
recent near-sterilizing events have destroyed most of a natural ecosystem
(e.g., areas near volcanic eruptions, burn scars from major wildfires,
oil spill sites, etc.). Couple species recovery patterns with selected
measurements of radiation balance, microclimate, toxicity and biogeochemistry.
- Determine key spectral indicators
of life's response to major environmental changes such as air and water
temperature changes, volcanic eruptions, pollution, deforestation, desertification,
etc.
- Create local and global models
of increasing complexity, of ecosystems and their response to changes
in the environment.
- Support technology development of advanced spectroscopic sensors (particularly hyperspectral), automation and information processing suited for obtaining key data on entire ecosystems and their environments.
Future extensions:
- Extend ecosystem perturbation
models to increasingly large sizes, eventually aiming for global predictive
models. Include remotely-sensed data, coupled with ground truth measurements,
to refine these models.
- Apply models obtained through
research on ecosystem response to the development of biomarkers for
remote detection of life.
- Develop models of ecosystem change that ultimately could assist our understanding of change in the geologic past.