Environmental Engineering Reference
In-Depth Information
Table 2.3
Zoomass Densities of Wild Terrestrial Mammals
Organisms
Live Weight (kg/ha)
All large wild mammals
Ruwenzori National Park (Uganda; 1960s)
199
Lake Manyara Park National Park (Tanzania)
192
Ngorongoro Crater (Tanzania, 1970s)
125
Masai Mara (Kenya)
100
Serengeti (Tanzania)
40-80
Gabon, lowland forest
10-60
African elephants
20-30
Eland
0.5-30
Wildebeests
0.3-20
Chimpanzees
0.2-1
All small mammals
1-3
Rodents
Common densities
<
0.2
Maxima
>
4
Note:
For comparison, densities of traditional African cattle herding are 6-30 kg/ha and the
highest zoomass densities of domesticated animals (Dutch Friesian dairy cows on pasture)
are 700-750 kg/ha.
biomass of soil bacteria, soil invertebrates, or the underground biomass of forests
yield uncertainties that are orders of magnitude larger. Table 2.3 offers both the
typical and the highest recorded densities of terrestrial mammals at a glance.
Estimates of Global Biomass
Realistic quantii cations of the Earth's phytomass are relatively recent: the i rst
attempt was made only in 1926 by Vladimir Ivanovich Vernadskii in his i rst edition
of
Biosfera
. He put the total weight of all “green matter” at 10
20
-10
21
g, and noted
that this enormous mass did not seem excessively large and that the total was of
the same order of magnitude as all of the biosphere's living matter (Vernadskii
1926). Vernadskii was correct in his second conclusion, for the heterotrophic
biomass adds up to only a small fraction of phytomass, but his phytomass estimate
was an enormous exaggeration. Vernadskii realized this error, and during the 1930s
he kept revising the total downward, but his last published value was, at 10
16
g, too
low (Vernadskii 1940).
