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early settlers introduced fires around 14,000 years
ago, it is only since Spanish colonization that fires
have become frequent. The Matorral is poorly
fire-adapted; human-induced fires cause major
and long-lasting damage. Seeds of native sclerophyllous species do not survive even low-intensity fires. Moreover, the capacity of regeneration
of these sclerophyllous species is very low—even
after cessation of livestock grazing—because of
the constant soil disruption and shoot consumption pressures from introduced rabbits and hares.
Logging and mining, with the ensuing roadways
and pollution that are created, have contributed
to habitat loss here. The increasing density of the
road network goes hand-in-hand with invasions
by exotic species and with deforestation, both
being positively correlated with distance to primary roads. The current rate of introductions of
invasive plant species is unprecedented in regional
history. Intentionally and unintentionally, nonnative species have spread fast and uncontrolled,
further promoted by the secondary plant and
animal invaders that come with the introduction
of controlled populations of livestock. The consequences can be severe. Introductions not only
modify patterns of abundance and distribution of
native species, they also cause local extinctions
and, especially in the case of plantations of exotic
trees, can significantly modify soil, microclimate
and fire characteristics, thus irreversibly altering
the environmental physiology of the ecosystem.
Despite its highly unique biodiversity, the Chilean Matorral is perhaps the least protected of the
world’s five major Mediterranean regions. Moreover, it is the least protected region in Chile at large.
The World Wildlife Fund has assessed this ecoregion’s conservation status to be Critical/Endangered. There remains a significant proportion of
currently unprotected natural and semi-natural
land with conservation potential, while human
pressure increases continually.
More intensive and efficient protection and conservation action is urgently required; some conservation schemes on private land and neighborhood initiatives have recently emerged. In 2010, the
new Altos de Cantillana Nature Sanctuary, located
approximately 25 miles (40 kilometers) from San-
Chile Intertidal Zones 461
tiago, was established by the Chilean government,
protecting 6,778 acres (2,743 hectares) of Matorral.
Although there is relatively little protected public
land in Chile, the concept of private land trusts has
recently gained momentum. These small parcels are
considered complementary to the National Public
System of Protected Areas—Sistema Nacional de
Áreas Silvestres Protegidas (SNASPE), which unifies conservation efforts within and between the
country’s national parks, reserves, and monuments.
Global warming scenarios generally point
to warmer and drier climate in Mediterranean
biomes such as the Chilean Matorral forests. The
pressure this will exert on plant and animal species
to relocate will only be exacerbated by increased
likelihood of fire; together these vectors point to
accelerated habitat fragmentation.
Stephan M. Funk
Further Reading
Cox, Robin L. and Emma C. Underwood. “The
Importance of Conserving Biodiversity Outside
of Protected Areas in Mediterranean Ecosystems.”
PLoS One 6, no. 1 (2011).
Figueroa, Javier A., S. A. Castro, P. A. Marquet,
and F. M. Jaksic. “Exotic Plant Invasions to the
Mediterranean Region of Chile: Causes, History
and Impacts.” Revista Chilena de Historia Natural
77, no. 3 (2004).
Funk, Stephan M. and John E. Fa. “Ecoregion
Prioritization Suggests an Armoury Not a Silver
Bullet for Conservation Planning.” PLoS One,
5, no. 1 (2010).
Gomez-Gonzalez, S., C. Torres-Diaz, G. Valencia, P.
Torres-Morales, L. A. Cavieres, and J. G. Pausas.
“Anthropogenic Fires Increase Alien and Native
Annual Species in the Chilean Coastal Matorral.”
Diversity and Distributions 17, no. 1 (2011).
Chile Intertidal Zones
Category: Marine and Oceanic Biomes.
Geographic Location: South America.
462 Chile Intertidal Zones
Summary: Chile has one of the world’s longest
and most diverse intertidal zones, nourished
by the Humboldt Current that flows along its
entire coast.
Chile is a long, narrow country that is defined by
the Andes mountain range on the east and by the
Pacific Ocean on the west. Chile is 2,672 miles
(4,300 kilometers) long and an average of 109 miles
(175 kilometers) wide. This long strip of coastal
land runs parallel to the Andes and extends from
mid-continent to Cape Horn, the southernmost
point of South America.
The coastal climate is strongly influenced by the
Humboldt Current. This slow, cold Pacific current
sustains one of the world’s richest fisheries along
the Chilean coast. Many forms of wildlife are also
found in abundance along the adjacent land areas.
The Humboldt Current begins north of the Antarctic and runs the full length of the Chilean coast,
bringing nutrient-rich waters that nourish the
intertidal zones. Intertidal zones along shorelines
are the areas between the high tide and the low tide
and can include many types of habitat: steep rocky
cliffs, sandy beaches, wetlands, and marshes.
The organisms that live here have become specially adapted to survive the significant changes in
temperature, salinity, moisture, acidity, dissolved
oxygen, and food supply that occur on a daily basis
due to the movement of the tides. Different plants
and animals that have excelled at dealing with different sets of conditions dominate zones at different tidal heights. This distribution pattern of different species along the shore in vertical bands is
referred to as intertidal zonation.
Varied climatic conditions along Chile’s long
coast also contribute to the diversity of intertidal
species: An extremely dry climate is typical of the
north, but the coast exhibits a rain-forest microclimate, as moisture from the sea is trapped by cliffs
and valleys; the central region of the country is
characterized by the hot, dry summers and mild,
wet winters of a Mediterranean climate; and the
southern region is cooler and wetter, classified as
an oceanic temperate climate.
The complex relationship between the Humboldt Current and the intertidal zones supports
a wealth of oceanic and land organisms. Near
the coast are found some of the world’s greatest
populations of shrimp, anchovies, squid, sardines,
salmon, and mackerel. Marine birds and mammals—such as penguins, pelicans, flamingos, bottle-nosed dolphins, whales, and sea lions—live off
of the smaller of these fish, mollusks, and crustaceans. Intertidal species such as sea urchins, starfish, and coral also contribute to this diverse, yet
fragile eco-community, as do seaweeds, kelp, and
shoreline grasses.
Many of these organisms are adapted to
extremes, as the local water may be fresh, brackish,
or salty. They may be subject to varied wave action,
and must be able to live exposed to air and sun, or
submerged in water. Many types of shellfish thrive
here, most notably the Chilean blue mussel, which
is harvested by humans regularly. Wild fisheries
and salmon fish farms have become very economically important to Chile in the past 30 years.
Human Impact and Conservation
Because there has been an increasing worldwide
demand for fish over the past several decades, wild
fisheries are being overexploited. Salmon farms
consume many of these wild fish, and also have
caused problems on some coastal areas due to pollution runoff, low oxygen zones, algal blooms, and
the spread of viruses into the marine environment.
Inland mining practices have also had a negative
impact on shoreline species. Forestry, pulp, and
paper industries are present in the south, releasing
pollutants that harm the intertidal zones.
The Chilean coast, including the intertidal zone,
is administered by the Ministry of National Defense
through the Marine Subsecretary, which addresses
issues related to national and state public goods
in the intertidal zones—including harvesting of
marine species. Under this Marine Subsecretary is
another division that regulates such diverse activities as aquaculture and harbors. State ownership
of the coast tends to occur in the extreme north or
south of Chile, as the other coastal lands became
private during the long colonial period.
Since the 1990s, there has been extensive
Chilean research on intertidal zones, and two
coastal marine research stations have been cre-
China Loess Plateau Mixed Forests, Central 463
ated: Estación Mehuín in southern Chile of the
Universidad Austral de Chile, and Estación Costera de Investigaciones Marinas in Las Cruces in
Central Chile of Pontificia Universidad Católica
de Chile.
In 2001, Oceana was founded. It is the largest international organization focused solely on
ocean conservation. The Oceana offices in North
America, Central America, South America, and
Europe work together on a limited number of
strategic, directed campaigns to achieve measurable outcomes that will help return the oceans
to former levels of abundance. (Oceana Chile is
located in Santiago, Chile.) In its first decade,
Oceana has achieved some policy victories for
marine life and habitats. As oceans play a key
role in regulating the earth’s temperatures, this
organization is currently considering the impacts
of global warming and is moving forward with
public education, legislation advocacy, and ecosystem protection.
Magdalena Ariadne Kim Muir
Further Reading
Bamfield Marine Sciences Centre Public Education
Program. “Oceanlink—All About the Ocean:
Exploring the Intertidal.” http://oceanlink.info/
biodiversity/intertidal/intertidal.html.
Castilla, J. C. “Roles of Experimental Marine Ecology
in Coastal Management and Conservation.”
Journal of Experimental Marine Biology and
Ecology 250, no. 1–2 (2000).
Heileman, S., R. Guevara, F. Chavez, A. Bertrand
and H. Soldi. “XVII-56 Humboldt Current: Large
Marine Ecosystems #13.” 2009. http://www.lme
.noaa.gov/lmeweb/LME_Report/lme_13.pdf.
China Loess Plateau
Mixed Forests, Central
Category: Forest Biomes.
Geographic Location: Asia.
Summary: This plateau, also known as the
Plateau of Yellow Earth or the North China Plain,
is the cradle of the Chinese civilization. After
more than 1,000 years of deforestation and soil
erosion, it is sparsely vegetated but parts of it are
being rehabilitated to its natural state.
The central loess plateau, extending across
250,000 square miles (650,000 square kilometers)
of north central China along the Yellow River, is
the largest loess deposit region in the world and
home to some 100 million people. Tilted upward
from southeast to northwest, its elevation ranges
from 1,600 to 10,000 feet (488 to 3,048 meters)
above sea level. The lush Qinling Mountains to
the south and the Mongolia Plateau to the north
set up its geographic limits, stretching broad climatic gradients.
The yellowish silt deposits called loess were
formed here up to 2.5 million years ago during
repeated waves of glaciation and wind from northern desert regions. Loess contains more nutrients
than sand, but because it is finer-grained, is one of
the most erosion-prone soils of the planet. Affected
by centuries of deforestation and overgrazing, and
exacerbated by summer monsoon rainfall and
subsequent flash floods, the China Loess Plateau
biome has become one of the most eroded areas of
the world. The Yellow River, its name given by the
silt that colors it, picks up roughly 1.8 billion tons
(1.6 billion metric tons) of runoff deposits every
year. Periodic dust storms also move large quantities of the yellow silt, while causing visibility problems in urban areas.
Flora and Fauna
Natural vegetation of the loess plateau has experienced degradation during the history of human
habitation (a period spanning several thousand
years), leaving only about five percent of forest cover in the entire region. The existing forest
patches are more commonly found in the southeast part of the plateau, where climate is more
favorable and where agricultural activities are limited by rocky soils and more mountainous topography. These mixed forests are comprised of trees
like aspen, oak, willow, birch, arborvitae, and pine.