Chile Intertidal Zones
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Chile Intertidal Zones 461 early settlers introduced fires around 14,000 years tiago, was established by the Chilean government, ago, it is only since Spanish colonization that fires protecting 6,778 acres (2,743 hectares) of Matorral. have become frequent. The Matorral is poorly Although there is relatively little protected public fire-adapted; human-induced fires cause major land in Chile, the concept of private land trusts has and long-lasting damage. Seeds of native sclero- recently gained momentum. These small parcels are phyllous species do not survive even low-inten- considered complementary to the National Public sity fires. Moreover, the capacity of regeneration System of Protected Areas—Sistema Nacional de of these sclerophyllous species is very low—even Áreas Silvestres Protegidas (SNASPE), which uni- after cessation of livestock grazing—because of fies conservation efforts within and between the the constant soil disruption and shoot consump- country’s national parks, reserves, and monuments. tion pressures from introduced rabbits and hares. Global warming scenarios generally point Logging and mining, with the ensuing roadways to warmer and drier climate in Mediterranean and pollution that are created, have contributed biomes such as the Chilean Matorral forests. The to habitat loss here. The increasing density of the pressure this will exert on plant and animal species road network goes hand-in-hand with invasions to relocate will only be exacerbated by increased by exotic species and with deforestation, both likelihood of fire; together these vectors point to being positively correlated with distance to pri- accelerated habitat fragmentation. mary roads. The current rate of introductions of invasive plant species is unprecedented in regional Stephan M. Funk history. Intentionally and unintentionally, nonna- tive species have spread fast and uncontrolled, Further Reading further promoted by the secondary plant and Cox, Robin L. and Emma C. Underwood. “The animal invaders that come with the introduction Importance of Conserving Biodiversity Outside of controlled populations of livestock. The con- of Protected Areas in Mediterranean Ecosystems.” sequences can be severe. Introductions not only PLoS One 6, no. 1 (2011). modify patterns of abundance and distribution of Figueroa, Javier A., S. A. Castro, P. A. Marquet, native species, they also cause local extinctions and F. M. Jaksic. “Exotic Plant Invasions to the and, especially in the case of plantations of exotic Mediterranean Region of Chile: Causes, History trees, can significantly modify soil, microclimate and Impacts.” Revista Chilena de Historia Natural and fire characteristics, thus irreversibly altering 77, no. 3 (2004). the environmental physiology of the ecosystem. Funk, Stephan M. and John E. Fa. “Ecoregion Despite its highly unique biodiversity, the Chil- Prioritization Suggests an Armoury Not a Silver ean Matorral is perhaps the least protected of the Bullet for Conservation Planning.” PLoS One, world’s five major Mediterranean regions. Moreo- 5, no. 1 (2010). ver, it is the least protected region in Chile at large. Gomez-Gonzalez, S., C. Torres-Diaz, G. Valencia, P. The World Wildlife Fund has assessed this ecore- Torres-Morales, L. A. Cavieres, and J. G. Pausas. gion’s conservation status to be Critical/Endan- “Anthropogenic Fires Increase Alien and Native gered. There remains a significant proportion of Annual Species in the Chilean Coastal Matorral.” currently unprotected natural and semi-natural Diversity and Distributions 17, no. 1 (2011). land with conservation potential, while human pressure increases continually. More intensive and efficient protection and con- servation action is urgently required; some con- servation schemes on private land and neighbor- Chile Intertidal Zones hood initiatives have recently emerged. In 2010, the new Altos de Cantillana Nature Sanctuary, located Category: Marine and Oceanic Biomes. approximately 25 miles (40 kilometers) from San- Geographic Location: South America. 462 Chile Intertidal Zones Summary: Chile has one of the world’s longest a wealth of oceanic and land organisms. Near and most diverse intertidal zones, nourished the coast are found some of the world’s greatest by the Humboldt Current that flows along its populations of shrimp, anchovies, squid, sardines, entire coast. salmon, and mackerel. Marine birds and mam- mals—such as penguins, pelicans, flamingos, bot- Chile is a long, narrow country that is defined by tle-nosed dolphins, whales, and sea lions—live off the Andes mountain range on the east and by the of the smaller of these fish, mollusks, and crusta- Pacific Ocean on the west. Chile is 2,672 miles ceans. Intertidal species such as sea urchins, star- (4,300 kilometers) long and an average of 109 miles fish, and coral also contribute to this diverse, yet (175 kilometers) wide. This long strip of coastal fragile eco-community, as do seaweeds, kelp, and land runs parallel to the Andes and extends from shoreline grasses. mid-continent to Cape Horn, the southernmost Many of these organisms are adapted to point of South America. extremes, as the local water may be fresh, brackish, The coastal climate is strongly influenced by the or salty. They may be subject to varied wave action, Humboldt Current. This slow, cold Pacific current and must be able to live exposed to air and sun, or sustains one of the world’s richest fisheries along submerged in water. Many types of shellfish thrive the Chilean coast. Many forms of wildlife are also here, most notably the Chilean blue mussel, which found in abundance along the adjacent land areas. is harvested by humans regularly. Wild fisheries The Humboldt Current begins north of the Ant- and salmon fish farms have become very economi- arctic and runs the full length of the Chilean coast, cally important to Chile in the past 30 years. bringing nutrient-rich waters that nourish the intertidal zones. Intertidal zones along shorelines Human Impact and Conservation are the areas between the high tide and the low tide Because there has been an increasing worldwide and can include many types of habitat: steep rocky demand for fish over the past several decades, wild cliffs, sandy beaches, wetlands, and marshes. fisheries are being overexploited. Salmon farms The organisms that live here have become spe- consume many of these wild fish, and also have cially adapted to survive the significant changes in caused problems on some coastal areas due to pol- temperature, salinity, moisture, acidity, dissolved lution runoff, low oxygen zones, algal blooms, and oxygen, and food supply that occur on a daily basis the spread of viruses into the marine environment. due to the movement of the tides. Different plants Inland mining practices have also had a negative and animals that have excelled at dealing with dif- impact on shoreline species. Forestry, pulp, and ferent sets of conditions dominate zones at differ- paper industries are present in the south, releasing ent tidal heights. This distribution pattern of dif- pollutants that harm the intertidal zones. ferent species along the shore in vertical bands is The Chilean coast, including the intertidal zone, referred to as intertidal zonation. is administered by the Ministry of National Defense Varied climatic conditions along Chile’s long through the Marine Subsecretary, which addresses coast also contribute to the diversity of intertidal issues related to national and state public goods species: An extremely dry climate is typical of the in the intertidal zones—including harvesting of north, but the coast exhibits a rain-forest microcli- marine species. Under this Marine Subsecretary is mate, as moisture from the sea is trapped by cliffs another division that regulates such diverse activi- and valleys; the central region of the country is ties as aquaculture and harbors. State ownership characterized by the hot, dry summers and mild, of the coast tends to occur in the extreme north or wet winters of a Mediterranean climate; and the south of Chile, as the other coastal lands became southern region is cooler and wetter, classified as private during the long colonial period. an oceanic temperate climate. Since the 1990s, there has been extensive The complex relationship between the Hum- Chilean research on intertidal zones, and two boldt Current and the intertidal zones supports coastal marine research stations have been cre- China Loess Plateau Mixed Forests, Central 463 ated: Estación Mehuín in southern Chile of the Summary: This plateau, also known as the Universidad Austral de Chile, and Estación Cos- Plateau of Yellow Earth or the North China Plain, tera de Investigaciones Marinas in Las Cruces in is the cradle of the Chinese civilization. After Central Chile of Pontificia Universidad Católica more than 1,000 years of deforestation and soil de Chile. erosion, it is sparsely vegetated but parts of it are In 2001, Oceana was founded. It is the larg- being rehabilitated to its natural state. est international organization focused solely on ocean conservation. The Oceana offices in North The central loess plateau, extending across America, Central America, South America, and 250,000 square miles (650,000 square kilometers) Europe work together on a limited number of of north central China along the Yellow River, is strategic, directed campaigns to achieve measur- the largest loess deposit region in the world and able outcomes that will help return the oceans home to some 100 million people. Tilted upward to former levels