Earth’s Major Biomes 137Average monthly precipitation in cm14
12
10
8
6
4
2
0
Months15202510
5
0
–5
–10
–15
–20
–15Average monthly temperature in°CJFMAMJJASONDEarl Scott/Science Source ImagesBased on data from http://www.worldclimate.comshrubs—often short, drought-resistant pine or scrub
oak trees that grow 1 to 3 m (3 to 10 ft) tall—usually
dominates chaparral. These plant species have evolved
adaptations that equip them to live where precipita-
tion is seasonal. During the rainy winter season, the
environment may be lush and green, and during the hot,
dry summer, the plants lie dormant. The hard, small,
leathery leaves of trees and shrubs resist water loss.
Many plants are also specifically fire adapted and
grow best in the months following a fire. Such growth is
possible because fire releases into the soil the nutrient
minerals present in the aboveground parts of the plants
that burned. The seeds and underground parts of plants
that survive fire make use of the newly availabile nutrient
minerals and sprout vigorously during winter rains. Mule
deer, wood rats, chipmunks, lizards, and many species of
birds are common animals of the chaparral. (For more
on the role fire plays in nature and on how humans have
disrupted this role, see the case study on page 154.)Chaparral
Some hilly temperate environments have mild winters
with abundant rainfall combined with hot, dry sum-
mers. Such Mediterranean climates, as they are called,
occur not only in the area around the Mediterranean
Sea but also in the North American Southwest, south-
western and southern Australia, central Chile, and
southwestern South Africa. On the mountain slopes of
southern California, this Mediterranean-type biome is
known as chaparral (Figure 6.9). Chaparral soil is thin
and often not very fertile. Wildfires occur naturally in
this environment and are par-
ticularly frequent in late summer
and autumn.
Chaparral vegetation looks
strikingly similar in different parts
of the world, even though the in-
dividual species differ by location.
A dense thicket of evergreen
chaparral A biome
with mild, moist
winters and hot,
dry summers;
vegetation is
typically small-leaved
evergreen shrubs
and small trees.>«>ÀÀ>ÊUÊ}ÕÀiÊÈ°Ê
Chaparral vegetation consists mainly of drought-resistant evergreen shrubs and small trees. Hot, dry summers and mild, rainy winters
characterize the chaparral. Photographed in California. Climate graph shows monthly temperatures and precipitation for Culver City,
California.
Interpreting Data
Using monthly averages, what is
the approximate average annual
precipitation in the California
chaparral?