Global Change and Our Common Future Papers from a Forum (1989) / Chapter Skim
Currently Skimming:
9. Terrestrial Ecosystems
9. Terrestrial Ecosystems
Pages 78-83
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 78... ...
Plants use nitrogen from the soil to capture energy from the sun and carbon dioxide . Soil microorganisms ultimately utilize much of that energy, in the process releasing carbon dioxide and methane as end products and nitrogen-containing trace gases as by-products of their activity.
|
From page 79... ...
When summed globally, these seasonal changes correlate very strongly with seasonal changes in carbon dioxide concentrations (Fung et al., 1987~ -- an exciting demonstration that satellitebased earth observation now allows truly global-scale research. Repeated observations over periods of years and decades will allow us to determine the effects of occasional events such as E1 Nina or the 1988 drought and of directional changes in the distribution of vegetation.
|
From page 80... ...
At least in terms of the composition of the atmosphere, the ongoing change is both much larger and much faster (Figure 9.1~. The concentration of carbon dioxide varied from 200 to 285 ppm during the glacial-interglacial cycle; it is now approximately 350 ppm, and it is increasing rapidly.
|
From page 81... ...
Of particular concern are the following: 1. The effects of increased carbon dioxide concentrations on the functioning of terrestrial ecosystems everywhere.
|
From page 82... ...
However, the global changes that have taken place to date are small relative to what can be expected in the next 50 years. Unless surprising progress is made, carbon dioxide concentrations soon will be more than 50 percent greater than the preindustrial values; most tropical forests worldwide will be a memory.
|
From page 83... ...
(ed.) , CO2 and Plants: The Response of Plants to Rising Levels of Atmospheric Carbon Dioxide.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.