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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.