Page 112 - Environment: The Science Behind the Stories

WEIGhING thE ISSUES consuming, and expensive, and it is not always successful. It

rEStOrING “NatUraL” COMMUNItIES is therefore best, whenever possible, to protect natural sys-
tems from degradation in the first place.
Practitioners of ecological restoration in North America often
aim to restore communities to their natural state. But what
does “natural” mean? Does it mean the state of the community
before industrialization? Before Europeans came to the New Earth’s Biomes
World? Before any people laid eyes on the community? Let’s
say Native Americans altered a forest community 8000 years Across the world, each location is home to different sets
ago by burning the underbrush regularly to improve hunting of species, leading to endless variety in community com-
and continued doing so until Europeans arrived 400 years ago position. However, communities in far-flung places often
and cut down the forest for farming. Today the area’s inhabit- share strong similarities in their structure and function.
ants want to restore the land to its “natural” forested state. This allows us to classify communities into broad types.
Should they try to recreate the forest of the Native Americans A biome is a major regional complex of similar commu-
or the forest that existed before Native Americans arrived? nities—a large-scale ecological unit recognized primarily
What values do you think underlie the desire for restoration? by its dominant plant type and vegetation structure. The
world contains a number of biomes, each covering large
geographic areas (Figure 4.17).
mi) of levees, and 200 water control structures. Because the Each biome encompasses a variety of communities that
Everglades provides drinking water for millions of Florida share similarities. For example, the eastern United States
citizens, as well as considerable tourism revenue, restoring supports the temperate deciduous forest biome. From New
its ecosystem services (pp. 21, 134–135, 170, 308) should Hampshire to the Great Lakes to eastern Texas, precipitation
prove economically beneficial as well as ecologically valu- and temperature are similar enough that most of the region’s
able. We will explore ecological restoration projects further natural plant cover consists of broad-leafed trees that lose
in Chapter 11 (pp. 307, 320). their leaves in winter. Within this region, however, there exist
As our population grows and development spreads, many different types of temperate deciduous forest, such as
ecological restoration is becoming an increasingly vital oak–hickory, beech–maple, and aspen–birch forests, each
conservation strategy. However, restoration is difficult, time- sufficiently different to be designated a separate community.

Pacific
Atlantic Ocean
Ocean
Tropic of Cancer 23.5° N
Pacific
Equator Ocean 0°
Indian CHAPTER 4 • S PEC i ES i n TERA CT i on S A nd Co mmuni T y E C ology
Tropic of Capricorn Ocean 23.5° S

Temperate deciduous forest Tropical rainforest Desert Chaparral
Temperate grassland Tropical dry forest Tundra Mountainous regions
Temperate rainforest Savanna Boreal forest Unvegetated regions
Figure 4.17 Biomes are distributed around the world, roughly correlated with latitude. 111

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