New Caledonia rain forests

Coordinates: 21°29′S 165°39′E / 21.49°S 165.65°E / -21.49; 165.65
Source: Wikipedia, the free encyclopedia.
New Caledonia rain forests
Tree ferns on Isle of Pines
Ecoregion territory (in purple)
Ecology
RealmAustralasian realm
Biometropical and subtropical moist broadleaf forests
Geography
Area14,001 km2 (5,406 sq mi)
CountriesNew Caledonia
Coordinates21°29′S 165°39′E / 21.49°S 165.65°E / -21.49; 165.65
Conservation
Conservation statusCritical/endangered
Protected7,872 km2%[1]

The New Caledonia rain forests are a

terrestrial ecoregion, located in New Caledonia in the South Pacific. It is a tropical moist broadleaf forest ecoregion, part of the Australasian realm
. [2] [3] [4]

Setting

Original distribution area of Melaleuca quinquenervia or Niaouli
Nothofagus is a plant genus that illustrates Gondwanan distribution, having descended from the supercontinent and existing in current day Australia, New Zealand, New Caledonia and Chile. Fossils have also recently been found in Antarctica.[5]

The ecoregion covers the

Isle of Pines
to the south of Grand Terre. The ecoregion covers an area of 14,600 square kilometers (5,600 sq mi).

Grand Terre is a long island that runs approximately north–south, with a mountain range down the center with five peaks that exceed 1500 meters elevation. The Loyalty Islands and Ile des Pins are much lower. New Caledonia lies astride the Tropic of Capricorn, between 19° and 23° south latitude, 1,200 km east of Australia and 1,500 km northeast of New Zealand.

The climate of the islands is

rainfall is highly seasonal, brought by trade winds that usually come from the east. Rainfall averages about 1,500 mm yearly on the Loyalty Islands, 2,000 mm at low elevations on eastern Grand Terre, and 2,000-4,000 mm at high elevations on Grand Terre. The western slopes of Grand Terre, which are in the rain shadow of the central mountain range, are much drier, and are home to the New Caledonia dry forests
ecoregion.

New Caledonia is an ancient fragment of Gondwana, the southern supercontinent. It separated from Australia 85 million years ago, and remained attached to New Zealand until 55 million years ago. It has been isolated from other land masses since then, although a number of plants and animals have been able to cross the straits separating New Caledonia from neighboring islands.

The forests are made up of laurel-leaved

understorey plants, invertebrates, and birds and bats
.

New Caledonia's fauna and flora derive from ancestral species isolated in the region when it broke away from Gondwana many tens of millions of years ago.[6] Not only endemic species have evolved here, but entire genera and even families are unique to the islands.

More tropical

Parasitaxus usta).[7] Again, of the 35 known species of Araucaria, 13 are endemic to New Caledonia.[8]

The world's largest extant species of fern, Sphaeropteris intermedia, also is endemic to New Caledonia. It is very common on acid ground, and grows about one metre per year on the east coast, usually on fallow ground or in forest clearings. There also are other species of Cyathea, notably Sphaeropteris novae-caledoniae.[9]

The islands soils derived largely from

phytotoxic
compounds of heavy metals such as nickel. Not many invader species can compete successfully with plants adapted to such challenging soils.

New Caledonia also is one of five regions on the planet where species of Nothofagus are indigenous; five species are known to occur here.[7]

Cloud forest formerly covered much of the tropical mountain and coastal areas of the world. The

exotic species
. The decline of much of the endemic fauna and flora is largely due to deforestation to accommodate
laurisilva
forests remain on Madeira, where they are found between 300 m and 1400 m altitude on the northern slope, and 700 m to 1600 m on the southern slope, and cover 149,5 km2.

The laurifolia appears in mountains of the coastal strip of New South Wales in Australia, New Guinea, New Caledonia, Tasmania, and New Zealand. The laurel forests of Australia, Tasmania, and New Zealand are home to species related to those in South Africa, Macaronesia, Madagascar, South Japan, Jeju island in Korea, Taiwan, South China coast, North America coasts to Panama and the Valdivian laurel forests, including southern beech (Nothofagus) through the connection of the Antarctic flora. Other typical flora include Winteraceae, Myrtaceae, southern sassafras (Atherospermataceae), conifers of Araucariaceae, Podocarpaceae, and Cupressaceae, and tree ferns.[10]

New Caledonia was an ancient fragment of the

endemic
plants and animals of Gondwanan origin have spread to the southern continents later.

The laurel forest of Australia, New Caledonia (Adenodaphne), and New Zealand have a number of other related species of the Valdivian laurel forest, through the connection of the Antarctic flora of gymnosperms like the podocarpus and deciduous Nothofagus. New Caledonia lies at the northern end of the ancient continent

Norfolk pine can be seen that grew on Zealandia about 180 million years ago during the Jurassic period, before it split from Gondwana.[12]

During glacial periods more of Zealandia becomes a

terrestrial rather than a marine environment. Zealandia was originally thought to have no native land mammal fauna, but a recent discovery in 2006 of a fossil mammal jaw from the Miocene in the Otago region shows otherwise.[13]

New Guinea and Northern Australia ecoregion are closely related. Over time Australia and New Caledonia drifted north. New Caledonia protected by the ocean remained unchanged preserving their species and Australia became drier; the humid Antarctic flora from Gondwana retreated to the east coast and Tasmania, while the rest of Australia became dominated by Acacia, Eucalyptus, and Casuarina, as well as xeric shrubs and grasses. Humans arrived in Australia 50–60,000 years ago, and used fire to reshape the vegetation of the continent; as a result, the Antarctic flora, also known as the rainforest flora in Australia, retreated to a few isolated areas composing less than 2% of Australia's land area.

Flora

The New Caledonia rain forests are made up of three predominant forest types. The lowland rain forests cover the Loyalty Islands, and the Iles des Pines and the lower elevations of Grand Terre. Montane forests cover the higher elevations of Grand Terre. The wet

ultramafic
rocks.

The predominant flora of New Caledonia rain forests is derived from the

angiosperm trees, including the Southern Hemisphere genus Nothofagus and trees and shrubs of families Myrtaceae and Proteaceae
.

The lowland forests are a generally a mixed-

species composition, interspersed with some single species stands. The predominant conifers are Araucaria columnaris, A. bernieri, Agathis lanceolata, A. ovata (Araucariaceae), and Dacrydium araucarioides, Dacrycarpus vieillardii and Falcatifolium taxoides (Podocarpaceae). Predominant angiosperm trees include Montrouziera cauliflora, Calophyllum caledonicum, Didymocheton spp., Neoguillauminia cleopatra, and Hernandia cordigera, together with species of the Proteaceae genera Kermadecia, Macadamia, and Sleumerodendron. Araucaria, Callistemon
, and Nothofagus predominate in the single-species stands.

The Montane rain forests are also mixed-species, predominantly the conifers Araucaria, Agathis, Podocarpus, Dacrydium, Libocedrus, and Acmopyle, and the angiosperms Metrosideros, Pterophylla, Quintinia, and Nothofagus.

The Maquis forests hold a great variety of species, with many

endemics. The ultramafic rocks, which formed in the deep ocean, are rich in metals, including nickel, magnesium, chromium, and manganese
, which are toxic to many plants. The predominant trees are stunted Araucarias.

Fauna

New Caledonia has one of the most enigmatic birds of the world, the endangered

Endemic birds of New Caledonia
for more details. The seashells from New Caledonia are in great demand by collectors.

Conservation

A 2017 assessment found that 7,872 km2, or 56%, of the ecoregion is in protected areas.[1] Protected areas include Parc de la Côte Oubliée (1222.59 km2), Blue River Provincial Park (220.72 km2), Parc de la Haute Dumbéa (91.71 km2), and Parc des Grandes Fougères (45.45 km2). Parc de la Zone Côtière Ouest (2552.68 km2) is partly in the New Caledonia dry forests ecoregion.[14]

See also

Biodiversity of New Caledonia

External links

  • "New Caledonia rain forests". Terrestrial Ecoregions. World Wildlife Fund.

References

  1. ^ a b Eric Dinerstein, David Olson, et al. (2017). An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm, BioScience, Volume 67, Issue 6, June 2017, Pages 534–545; Supplemental material 2 table S1b. [1]
  2. ^ "Map of Ecoregions 2017". Resolve. Retrieved August 20, 2021.
  3. ^ "New Caledonia rain forests". Digital Observatory for Protected Areas. Retrieved August 20, 2021.
  4. ^ "New Caledonia rain forests". The Encyclopedia of Earth. Retrieved August 20, 2021.
  5. ^ Li, H.M.; Zhou, Z.K. (2007). "Fossil nothofagaceous leaves from the Eocene of western Antarctica and their bearing on the origin, dispersal and systematics of Nothofagus". Science in China. 50 (10): 1525–1535.
  6. doi:10.1016/j.earscirev.2005.02.004
    .
  7. ^ a b Dossier, La flore de Nouvelle-Calédonie - Première partie
  8. ^ New Caledonia, p. 26, at Google Books By Leanne Logan, Geert Cole
  9. ^ Dossier > La flore de Nouvelle-Calédonie - Deuxième partie
  10. ^ Fujiwara, Kazue and Elgene O. Box (1999)."Evergreen Broad-Leaved Forests in Japan and Eastern North America: Vegetation Shift under Climatic Warming" in Conference on Recent Shifts in Vegetation Boundaries of Deciduous Forests F. Klötzli, G.-R. Walther, eds. Birkhauser, Basel. doi=10.1007/978-3-0348-8722-9_16
  11. ^ Keith Lewis; Scott D. Nodder; Lionel Carter (11 January 2007). "Zealandia: the New Zealand continent". Te Ara — the Encyclopedia of New Zealand. Retrieved 22 February 2007.
  12. ^ Fossil forest: Features of Curio Bay/Porpoise Bay Archived 2008-10-17 at the Wayback Machine Retrieved on 2007-11-06
  13. ISBN 978-0-14-302088-2
    .
  14. ^ "New Caledonia". Protected Planet. Accessed 23 May 2020

Flannery, Tim (1994). The Future Eaters. Grove Press, New York.

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