Page 214 - Environment: The Science Behind the Stories

Percent of NPP used by people
80–100 30–40
70–80 20–30
60–70 10–20
50–60 0–10
40–50 ≤0

Figure 2 The proportion of earth’s net primary production that people appropriate varies from region to
region. Regions that are densely populated or intensively farmed exert the heaviest impact. Source: Haberl, H.,
et al., 2007. Quantifying and mapping the human appropriation of net primary production in Earth’s terrestrial ecosystems. Proc. Natl.
Acad. Sci. 104:12942–12947, Fig 1b. © 2007 National Academy of Sciences, U.S.A. By permission.

as the boreal forest, Arctic tundra, instance, North Americans and Euro- that we are using a great deal of Earth’s
Himalayas, and Sahara Desert), peans import timber logged from the plant matter already, so that schemes
humans consume almost no NPP. In Amazon basin, as well as soybeans and to expand biomass energy production
North America, NPP use is heaviest in beef grown in areas where Amazonian (pp. 584–590) may not be wise.
the East, Midwest, and Great Plains. In forest was cleared. Through global Environmental scientists who
general, the map shows heavy appro- trade, we redistribute the products we have commented on the paper agree
priation of NPP in areas where popu- gain from the planet’s NPP. As a result, and say the team’s data should give
lation is dense relative to the area’s the environmental impacts of our con- us pause. As Jonathan Foley of the
vegetative production. sumption are often felt far from where University of Wisconsin and his col-
The map does not fully show we consume products. leagues put it, “Ultimately, we need to
the effects of resource consumption By showing areas of high and low question how much of the biosphere’s
due to affluence. Wealthy societies impact, maps like the one produced in productivity we can appropriate before
tend to import food, fiber, energy, and this project can help us to make better planetary systems begin to break
products from other places, and this decisions and minimize our impacts on down. 30%? 40%? 50%? More?
consumption can drive environmental ecosystems and ecosystem services. . . . Or have we already crossed that
degradation in poorer regions. For Haberl’s team also says its data show threshold?”

happens when large numbers of poor people rapidly become Yellow River that the once-mighty waterway now dries up in
more affluent,” in the words of Earth Policy Institute president many stretches. Although China is reducing its air pollution CHAPTER 8 • Hum A n Po P ul AT i on
Lester Brown. While millions of Chinese are increasing their from industry and charcoal-burning homes, the country faces
material wealth and their resource consumption, the country new urban pollution and congestion threats from rapidly ris-
is battling unprecedented environmental challenges brought ing numbers of automobiles. In August 2010, for example,
about by its rapid economic development. Intensive agricul- a 100-km (60-mi) traffic jam formed on the outskirts of the
ture has expanded westward out of the country’s moist rice- capital city of Beijing and persisted for more than 10 days!
growing areas, causing farmland to erode and literally blow Such issues are not unique to China. As the world’s other
away, much like the Dust Bowl tragedy that befell the U.S. industrializing countries strive to attain the material prosper-
heartland in the 1930s (pp. 242–243). China has overpumped ity that industrialized nations enjoy, they too may soon face
aquifers and has drawn so much water for irrigation from the many of the same challenges as China. 213

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