Environmental Engineering Reference
In-Depth Information
Table 11.1
Comparison of the Global Estimates of the Human Appropriation of the Net Primary Pro-
ductivity (HANPP)
Study
Period of Estimate
HANPP Mean (%)
HANPP Range (%)
Vitousek et al. (1986)
Late 1970s
27
3-39
Wright (1990)
1980s
24
Rojstaczer, Sterling,
and Moore (2001)
1990s
32
10-55
Imhoff et al. (2004b)
1990s
20
14-26
Haberl et al. (2007)
2000
24
Note:
Except for Wright, the rates were calculated using standard (consensus) estimates of
global NPP close to 60 Gt C/year.
decline during the nineteenth century (from 71% in 1800) followed by an increase
until the later 1950s and then another decrease to 68% by the year 2000.
Krausmann (2001) presented only a slightly shorter trajectory for Austria between
1830 and 1995, with the HANPP declining from about 60% in 1830 to 48% by
1970 and then rising slightly to 51% by 1995. Because of the higher productivity
of managed crop and forest phytomass, harvests in the mid-1990s were more than
70% above the 1840s mean, yet 23% more phytomass remained in the terrestrial
ecosystem than in 1830. The calculation of HANPP values for the Philippines
between 1910 and 2003 (the period of massive deforestation, a tenfold increase in
population, and impressive gains in average crop yields) showed a rapid increase
from claiming 35% of potential primary production in 1910 to slightly above 60%
by 1970, with constant values thereafter (Kastner 2009).
Schwarzmüler (2009) examined the changes in Spain's HANPP between 1955
and 2003, a time when the country's cropland declined and its forest cover expanded
and when, thanks largely to higher crop yields, its phytomass harvest grew by more
than 50% to more than 100 Mt of dry matter a year. At the beginning of that period
Spain's HANPP was about 67% of potential production; half a century later it had
declined to 61%, still rather high when compared to other high-income countries'
HANPP and, of course, well above the global mean. Finally, Prasad and Badarinth
(2004) calculated that between 1961 and 1998, India's HANPP increased by about
28%, a much slower growth than the expansion of India's population, which more
than doubled during the same period.
Vitousek et al. (1986) reduced a complex exercise based on numerous question-
able assumptions and relying on rough estimates with undei ned error margins to
