Flora of Indonesia

A melting pot of Indonesian flora in Cibodas botanical garden, Indonesia.

Thefloraconsists of many unique varieties of tropical plants. Blessed with atropicalclimate and roughly 17,000 islands,Indonesiais the nation with the second highestbiodiversityin the world. Theflora of Indonesiareflects an intermingling ofAsian,Australianand unique, Indonesian lineages. This is due to the geography of Indonesia, located between the aforementioned continents. The archipelago consists of a variety of regions, from thetropical rain forestsof the northern lowlands and the seasonal forests of the southern lowlands through the hill and mountain vegetation, to subalpine shrub vegetation. With the second longest coastline in the world, Indonesia also has many swamps and other varieties of coastal vegetation. Combined, these all give rise to a huge floral biodiversity. There are about 28,000 species of flowering plants documented in Indonesia, including 2500orchids,122 species ofbamboo,over 350 species ofrattanand 400 species ofDipterocarpus,includingebony,sandalwoodandteakwood. Indonesia is also home to some unusual species ofcarnivorous plants.One exceptional species is known asRafflesia arnoldi,named afterSir Thomas Stamford Rafflesand Dr.Thomas Arnold,who discovered the flower in the depths ofBengkulu,southwestSumatra.This parasitic plant has the largest flower of any plant, does not produce leaves and grows only on one species oflianaon the rainforest floor. Another unusual plant isAmorphophallus titanumfromSumatra.Numerous species of insect trappingpitcher plants(Nepenthesspp.) can also be found inBorneo,Sumatra,and other islands of theIndonesian archipelago.There are a staggering 6000 traditionalmedicinal plantsused asJamu.,

Origins of Indonesian Flora

The origin of flora in Indonesia is a result ofgeographicalandgeologicalevents involving the Asian andAustralasiancontinents.The present island ofNew Guineawas connected with the Australian continent, forming asupercontinentcalledGondwana.This supercontinent began to break up 140 million years ago, and the New Guinea region moved towards theequator.As a result, animals from New Guinea travelled to the Australian continent and vice versa, resulting in large amounts of speciation in the many newecosystems.This exchange continued to occur until the two landmasses separated completely.

Asian lineages in Indonesia are the result of the reformation of theLaurasiasupercontinent, which existed after the break-up ofRodiniaaround 1 billion years ago. Around 200 million years ago, the Laurasian supercontinent split completely, forming the continents ofLaurentia(nowthe Americas) andEurasia.Despite this separation, the mainland of the Eurasian continent was not separated completely from the Indonesianarchipelago.As a result, organisms from the Eurasian mainland could colonize the archipelago; and, under different environmental pressures, new species diverged.

In the nineteenth century,Alfred Russel Wallaceproposed the idea of theWallace Line,which is a line that divides Indonesian archipelago into two regions, the Asian biogeographical region (Sundaland) and the Australasian biogeographical Region (Wallacea). The line runs through theIndonesian Archipelago,betweenBorneoandSulawesi(Celebes); and betweenBaliandLombok.

The Indonesian archipelago, home of theSpice Islands,has been known since ancient times as a source of spices, such ascloves,nutmeg,andblack pepper.TheMaluku Islandswere, until the late eighteenth century, the only source of many economically significant spices. In the colonial era, cloves and nutmeg were the most valuable commodities behind gold and silver for European colonists. During the colonial era in Indonesia, the Dutch also created many plantations ofcoffee,teaandsugar cane,mostly inJava.

During the history of Indonesia, many foreign plants fromIndia,China, and Europe have been introduced to the archipelago. Plant species such as tea, coffee andrubber treehave become established.

Vegetation Types

The Distribution of Indonesian vegetation

Indonesia's terrestrial flora can be divided into severalvegetationgroups. The most important factor is rainfall, followed by temperature, which both affect water availability. The distribution of Indonesian flora is dominated by broadleaf evergreen forests. This is mostly seen in the regions where population density is still relatively low, such as Sumatra, Borneo, Sulawesi, and West Papua. On Java and Bali, the vegetation is dominated by cultivated plants. Swamp forests,mangrove,andNypa fruticansforests are found along the coast. In the mountainous regions, subalpine and alpine vegetation is dominant. In the lesser Sunda islands, where rainfall is not as plentiful as in other parts of Indonesia, grasslands are regularly seen.

Biodiversity

The flower ofAmorphophallus titanumatBogor Botanical Gardens

According to theConservation International,there are two biodiversity regions in Indonesia:WallaceaandSundaland.The provinces ofWest PapuaandPapuaare also extremely biodiverse.Lorentz National Park,located in the province of Papua, was declared aWorld Heritage Sitein 1999 byUNESCO.

Sundaland

Sundaland, which is located on the west part of theIndonesianarchipelago, holds about 25,000 different species of plants. 15,000 of them are endemic to this region and cannot be found anywhere else.Scyphostegiaceaeis a plant family represented by a single species,Scyphostegia borneensis,which is endemic toBorneo.Another 155 species ofDipterocarpusare endemic to this island. Borneo also has more than 2,000 species of orchids. The forests inSumatrainclude more than 100 species ofDipterocarpus,nearly a dozen of them are endemic to this island. The island ofJavahas about 270 endemicorchidspecies. It is home to Mentimun Jaws (Alsomitra macrocarpa) which has gliding seeds

At least 117 plant genera are endemic to this biodiversity hotspot. 59 of them are found in Borneo and 17 in Sumatra. Unique plants from this region are similar to ones from the Asian continent, examples includeRafflesia arnoldii,pitcher plantsandJavanese Edelweiss(Anaphalis javanica) as examples.

Flowers ofEucalyptus deglupta

Wallacea

It isestimatedthat there are over 10,000 species of plants in this biodiversity hotspot region. About 1,200 species and 12 genera are endemic. The island ofSulawesihas about 500 endemic plant species. The islands ofMoluccahave about 300 endemic plant species and theLesser Sunda Islandsare home to at least 110 endemic plant species. Little is known about the flora of this region. Three of these unique species,Agathis,Pterocarpus indicusandEucalyptus deglupta,are examples.

Papua Barat and Papua

The flora of this region is influenced by theAustraliancontinent. This region contains a wide array of environments, from snow-capped mountains, lowland wetlands, to tropical marine environment. This geographical variation results in a large diversity of plant species. In 2020, a group of 99 researchers published a checklist of the flora ofNew Guinea,presenting a total number of 13,634 species that occur on the island with 7,616 species occurring in the Indonesian part, the Papua Barat and Papua Provinces.An astonishing 60-90% of them may be endemic to New Guinea and according to recent estimation the endemic plants encompasses 68% of the total known species.This region has been poorly explored so the actual number of endemic species is unknown.

Indonesia's National Flowers

Melati(Jasminum sambac), a small white flower with a sweet fragrance, is the national flower of Indonesia,together withAnggrek Bulan(Phalaenopsis amabilis) andPadma Raksasa Rafflesia(Rafflesia arnoldii). All three were chosen onWorld Environment Dayon 5 June 1990 by PresidentSoeharto.On another occasionBunga Bangkai(Titan arum,Amorphophallus titanum) was also added aspuspa langkatogether with Rafflesia. Each individual province also has its ownfloral emblems.

National Love Flora and Fauna Day

To build interest and awareness for Indonesian flora and fauna, the government declared the 5th of November as National Love Flora and Fauna Day. Annually there are postage stamps released in honor of this holiday. They depict plants and animals that are endemic or unique to a specific region or a province of Indonesia.

Current Issues

Deforestationis a major problem in Indonesia. The current rate is a loss of 2 million hectares per year.As a highly populous, developing country that isindustrializingrapidly, the need of natural resources and land is steadily increasing. Illegally createdwildfirescause heavysmogaround Indonesia's neighbouring countries. The widespread deforestation and other environmental destruction in Indonesia has often been described by academics as anecocide.

According to the Indonesian department of forestry, there are currently 174 plants endemic to Indonesia listed as endangered species.

See also

• List of Indonesian floral emblems
• List of national parks of Indonesia
• Geography of Indonesia
• Fauna of Indonesia
• The useful plants of the Dutch East Indies

External links

• ASEAN Regional Centre for Biodiversity Conservation
• The Biodiversity hotspots
• (in Indonesian)PIKA Database of endemic Flora and Fauna in Indonesia
• An article about Indonesian vegetation
• Digital Flora of Indonesia