Harvest management - Ecological Applications: Toward a Sustainable World - page 183

Control

Equilibrium model

Tundra

Taiga/Tundra

Boreal Conifer Forest

Temp. Evergreen Forest

Temperate Mixed Forest

Tropical Broadleaf Forest

Savanna/Woodland

Shrub/Woodland

Grassland

Transient model

Arid Lands

Plate 11.3 (Fig. 11.3 on page 296) Simulated distribution of biomes throughout the world using contrasting climate change
models. Biomes are regional ecosystems characterized by distinct types of vegetation fi tted to the prevailing physical
conditions. (a) The 'control' output represents the current distribution of biomes. (b) Output from an 'equilibrium' model, in
which the doubling of CO 2 is assumed to produce its full temperature effect instantaneously. (c) Output for a 'transient
model', in which atmospheric CO 2 responds to dynamic feedback between atmosphere and oceans, achieving only about
65% of the eventual predicted temperature change at the time of CO 2 doubling. Under both scenarios, forests shift north-
wards to currently unforested areas. However, in temperate latitudes the transient model produces much lower increases in
temperature and larger increases in precipitation than the equilibrium model, with consequent differences in the distribu-
tion of biomes in the two cases. (Tundra is a treeless plain, Boreal (= northern) Conifer Forest consists of needle-leaf trees,
while Taiga/Tundra is intermediate between the two, with tundra vegetation and scattered conifer trees. Savanna is
grassland with scattered trees.) (From Neilson & Drapek, 1998.)