Chilean matorral forests

• Category: Forest Biomes.
• Geographic Location: South America.
• Summary: The Chilean Matorral ecosystem is rich with wildlife, much of it endemic, but human activity and low protection status present a continuing challenge.

Outside of the Mediterranean Sea area itself, Mediterranean-type ecosystems worldwide are found in only a few areas, including the southwestern coast of Australia, the Cape of Good Hope area in South Africa, the coastal chaparral zone of California, and one part of South America: the Chilean Matorral. The term matorral refers to the Spanish word mata for scrub vegetation. The Chilean Matorral covers an area of roughly 57,300 square miles (148,000 square kilometers), predominately a patchwork of small parks, agricultural areas, private lands, towns, and cities. Chile's capital, Santiago, is located here, as are other urban centers.

The Matorral is a narrow stretch of land in central Chile, extending south from one of the driest deserts in the world, the Atacama, to the mixed deciduous-evergreen temperate zone known as the Valdivian forests. The Matorral is about 350 miles (563 kilometers) long and 62 miles (100 kilometers) wide. Here, the summers are hot and dry and prone to drought conditions; winters are wet and mild. The mean annual temperature is 54 degrees F (12.2 degrees C). The native plant and animal communities in the Chilean Matorral biome are species-rich, with a very high proportion of endemism (found only in this ecosystem), particularly among plants.

Flora and Fauna

As a plant community, Matorral refers to a zone of sclerophyll shrubs and trees (i.e., evergreen “hard-leaved” woody vegetation with small, waxy leaves that prevent water loss in the dry summer); cacti, bromeliads, and palms; and diverse understories of herbs, vines, and grasses. Most of the present scrubland was created by human activity and is a successional remnant of the native sclerophyllous forest. It now exists as a mosaic of shrubs and trees within a matrix of naturalized herbaceous plants.

This land hosts animals that are specially adapted to their unique habitat and cannot be found anywhere else on Earth—making them extremely rare and dependent upon protected areas for their survival. These include many small mammals, such as the chilla, a fox-like animal; the yaca (mouse opossum); and the kodkod, the smallest wildcat in the Americas. Several lizard species are also endemic to the Chilean Matorral, as are 15 known species of birds. Among the latter are the Chilean mockingbird; three varieties of tapaculo, two species of parrots, the giant hummingbird; and some predatory species such as the aplomado falcon, cinereous harrier, and the short-eared owl.

Human Impact

The ecoregion's core, the Central Valley, constitutes Chile's most intensively inhabited area. It is very fertile and is the agricultural heartland with booming wine, vegetable, and fruit industries. In the more southerly parts, fruit, crops, pasture, and fire-prone pine and eucalyptus plantations are widespread. Because of the high agricultural value, the Central Valley of Chile has been highly modified since the arrival of Europeans. Although 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, but 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 Worldwide Fund for Nature (formerly 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 Santiago, 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. Despite these gains, only 0.5% of the Chilean matorral forest is protected.

Global warming scenarios generally point to warmer and drier climate in Mediterranean biomes such as the Chilean Matorral forests. Climate change has caused droughts in the area, which makes them more prone to wildfires. The pressure this will exert on plant and animal species to relocate and accelerate habitat fragmentation.

Bibliography

Cox, Robin L., and Emma C. Underwood. "The Importance of Conserving Biodiversity Outside of Protected Areas in Mediterranean Ecosystems." PLOS ONE, vol. 6, no. 1, 2011, pp. 1-8.

Figueroa, Javier A., et al. "Exotic Plant Invasions to the Mediterranean Region of Chile: Causes, History and Impacts." Revista Chilena de Historia Natural, vol. 77, no. 3, 2004, pp. 465-83.

Funk, Stephan M., and John E. Fa. "Ecoregion Prioritization Suggests an Armoury Not a Silver Bullet for Conservation Planning." PLOS ONE, vol. 5, no. 1, 2010, pp. 1-14.

Gomez-Gonzalez, S., et al. "Anthropogenic Fires Increase Alien and Native Annual Species in the Chilean Coastal Matorral." Diversity and Distributions, vol. 17, no. 1, 2011, pp. 58-67.

Ortiz, Jose. "Compound and Simple Leaf Woody Species of the Chilean Matorral Are Equally Affected by Extreme Drought." Research Square, 16 Mar. 2022, doi.org/10.21203/rs.3.rs-1440069/v1. Accessed 30 Oct. 2024.