South Malesian Evergreen Lowland Rain Forest
Lowland rain forest in this BioProvince is now largely confined to isolated remnants such as on Nusa Kambanga (an island off the coast of south-central Java). It is a relict forest but still includes rare endemic species such as the giant voodoo lily Amorphophallus decus-silvae (Araceae). Other stands occur at Lebakharjo (a strip of lowland forest on the south coast of east Java) and on Mount Wayang in west Java. However, unlike the lowland rain forest of Borneo and Sumatra where the dominant trees are dipterocarps, most of the lowland forest of Java and other parts of this BioProvince have no dominant species or family and because of their variability no ‘typical’ mix of species can be identified. Nevertheless, certain tree species are more common than others. In the remnant forest of west Java these include Artocarpus elasticus, Dysoxylum caulostachyum, Lansium domesticum and Planchonia valida.
South Malesian Lowland Deciduous Forest
These forests are confined to areas of Java, Bali and other islands where there are four or more dry months. They have a lightly closed canopy reaching about 25 m in height, but a few emergent species, such as Salmalia malabarica, reach greater heights. The typical canopy species in eastern Java and Bali include Acacia leucophloea, Ailanthus integrifolia, Albizia lebbekoides, Bauhinia malabarica, Cassia fistula, Dillenia pentagyna, Homalium tomentosa, Phyllanthus emblica, Tetrameles nubiiflora and the endemic Pterocymbium javanicum (Sterculiaceae). Also characteristic are the giant palms Borassus flabellifera and Corypha utan. The massive leaves of Corypha can reach 2 m in diameter. This species also has the second largest inflorescence in the plant kingdom reaching 4.5 m at the top of the palm and setting hundreds of thousands of fruit. However, it takes up to 70 years to flower and then dies. The shrub layer includes Tabernaemontana pauciflora and the endemic Munronia javanica (Meliaceae). Many of the herb layer species such as Glinus lotoides, Helicteres angustifolia and Turraea pubescens with its ant-dispersed seeds, are confined to deciduous forest. Other include lilies such as the yellow flowered Curligo orchioides and large white flowered Crinum asiaticum, and one may also encounter the attractive purple endemic orchid Nervilia campestris (Orchidaceae). At the onset of the wet season these forest display a riot of colour from the forest floor to the canopy. Particularly impressive are the dark red, bell-like flowers of Pterocymbium javanicum. Another unusual deciduous forest can be found on Bali’s Prapat Agung Peninsula. Here the forest is almost entirely dominated by Manilkara kauki, but this is thought to represent a mature stage of early succession that became established after some major disruption, probably fire during a very dry period. In the moist deciduous forest of the Meru Betiri National Park forest in east Java, large trees such as Anthocarpus elacticus, Ficus benjamina, Kleinhovia hospita, Langerstroemia flos-reginae, Planchonia valida, Spondias pinnata and the endemic or near endemic Bischofia javanica (Phyllanthaceae) and Pterospermum javanicum (Malvaceae) still occur, but because of past disturbance there is rarely a continous canopy. Understory trees include Alpinia striata, Baringtonia asiatica, Voacanga grandifolia and the endemic giant bamboo Gigantochloa manggong (Poaceae). Other endemic species include Balanophora fungosa (Rubiaceae) and the famous giant flowered Rafflesia zollingeriana (Rafflesiaceae).
South Malesian Dipterocarp Forest
On Sumbawa three layered Dipterocarpus retusus forest can be found on the northwestern slopes of Mount Batulante. The first layer mainly comprises giant emergent trees of the leguminous Serianthos minahassae. Its umbrella-like crowns can reach heights of up to 60 m, but no dipterocarps reach these heights. The second layer or canopy is about 40 m high and dominated by Dipterocarpus retusus. Other trees include Cinnamomum culilaban, Platea excelsea and species of Dysoxylum and Elaeocarpus. Many of these canopy trees become festooned with the beard lichen Usnea barbata a feature more usually associated with upper montane forests. Shade-loving trees and shrubs make up much of the third layer including the endemic Archidendron (Abarema) harmsii (Fabaceae) and Septogarcinia sumbawaensis (Clusiaceae). These lower layer trees support a wealth of epiphytic ferns and orchids. The forest floor vegetation is also very diverse with many small shrubs and herbs. Interestingly, dipterocarps are replaced by the Sumbawa endemic Heritiera gigantea (Sterculiaceae) on the drier northern and eastern slopes of Mount Batulante.
South Malesian Freshwater Swamp Forest
Most of the swamp forests have now disappeared from Java and were probably never present on Bali. Estimates suggest there were originally about 72,000 ha on Java. This has now been reduced to about 7,700 ha, of which 2,600 ha are in conservation areas. They generally formed in depressions such as the craters of ancient volcanoes, or are associated with river flood plains. All were of the topogenous type while the deep rain-fed (ombrogenous) swamp forests so extensive on Borneo and Sumatra do not occur. Today the largest area of swamp forest in Java occurs at the Rawa Danau Reserve. Here the dominant trees are Alstonia spathulata, Barringtonia racemosa, Elaeocarpus macrocerus, Ficus retusa, Gluta renghas and Mangifera gedeba. Many of the trees have supportive structures associated with their trunks such as long winding buttresses or stilt roots, and probably reflect the fact that the soils are relatively unstable. Species tend to to relatively few in numbers probably because few can tolerate the prolonged inundation. Other sites include Lobbok, which is said to be the largest peatswamp forest in Java and possibly the largest topogenous peatswamp in Indonesia.
South Malesian Mixed Montane Rain Forest
On Mount Gede and Mount Pangrango between altitudes of about 1400-2900 m the mountain forests are distinctly different from those of the lowlands. These forests are not homogenous and show a degree of variation with altitude. However, at about 2400 m on Mount Pangrango they have a stratification comprising four layers including the ground layer. The first layer or canopy ranges from about 15-20 m in height and typically includes Acronodia punctata, Myrsine affinis, Polyosma ilicifolia and Symplocos sessilifolia. Altringia excelsa, Schima wallichii and the endemic or near endemic Castanopsis javanica (Fagaceae) may also be present but these tend to be more abundant at slightly lower parts of the montane forest. In fact, Altringia excelsa dominates parts of the lower montane forest in the Mt Gede-Pangrango National Park. A number of these taller species, particularly Polyosma ilicifolia are also common in the second layer, which ranges in height from 5-15 m. Other species include Vaccinium laurifolium, Viburnum coriaceum and there may be endemic or near endemic species such as Ehretia javanica (Boraginaceae), Helicia javanica (Proteaceae), Lithocarpus indutus (Fagaceae), Symplocos costata (Symplocaceae) and Neolitsea javanica (Lauraceae). The third layer contains small trees and shrubs up to about 5 m high and typically including the endemic Ardisia javanica (Myrsinaceae). The endemic tree fern Cyathea crenulata (Cyatheaceae) may also be present while other endemic or near endemic trees and shrubs are Endiandra javanica (Lauraceae), Euonymus javanica (Celastraceae) and Olea javanica (Oleaceae). Climbers are well represented and include vines like the endemic Schisandra elongata (Schisandraceae), although lianas seem to be relatively few in numbers but include the endemic Lonicera javanica (Caprifoliaceae). Among the rich epiphytic flora the attractive fern Asplenium nidus is frequently encountered, but there is also a rich diversity of other ferns and orchids. Among the latter are Appendicula ramosa, Bulbophyllum uniflorum, Cyperorchis rosea, Liparis pallida and Malaxis blumei. At ground level the typical herbaceous species include Myriactis javanica, Ranunculus javanicus and Swertia javanica, but none of these despite these names are endemic to Java. However, other possibly less common herb-layer species such as Amomum hochreuteneri (Zingiberaceae) and Zingiber odoriferum (Zingiberaceae) are endemic.
South Malesian Podocarp Mountain Moss Forest
At altitudes exceeding 1700 m podocarps become the dominant tree species. On Java’s Mount Gedeh three species occur: Podocarpus amara, P. imbricata and P. neriifolia. These are the only conifer and, in fact, the only gymnoperms indigenous to Mt Gedeh. The transformation to podocarps occurs very suddenly and people have wondered at what climatic factors could exist to produce such a marked change. Other large trees include Engelhardtia serrata and Schima noronha, while smaller trees are Elaeopcarpus acronodia, Meliosma nervosa, Michelia montana, Macropanax dispermum and Pygeum latifolium. All of these trees are covered in a luxuriant growth of bryophytes the most abundant of which is the festooning Papillaria fuscescens. Other epiphytes include an abundance of ferns, such as the attractive bird’s nest fern Asplenium nidus, and orchids like the endemic Schoenorchis juncifolia (Orchidaceae). The forest floor tends to be quite open with a luxuriant growth of terrestrial ferns such as the giant Polypodium nigrescens. Another feature of these forests are numerous small bog land areas in which the purplish-red pitcher plant Nepenthes melamphora frequently occurs. Among the abundant lianas Fagara scandens is particularly conspicuous. Its huge stubby spines give it a nasty appearance. Other climbers include the aroid Epipremnum pinnatum.
South Malesian Casuarina Montane Forest
Forest dominated by the endemic Casuarina junghuhniana (Casuarinaceae) occur in upland areas east of Mt Lawu on the border of central and east Java. This species and the associated Podocarpus imbricatus are pioneer species colonizing areas that have been stripped of their vegetation by disturbance such as landslips, volcanic ash falls or fires. However, neither of these will regenerate under a closed canopy and so usually have a limited existence. Nevertheless, unlike most pioneer species Casuarina junghuhniana is long-lived and can grow to a great height (up to 45 m). At altitudes over 1400 m, it often forms monospecific stands and can grow at altitudes up to 3000 m. Impressive forest can be seen, for example, on Mt Argapura. Beneath the canopy a variety of shrubs occur include the large green Euphorbia javanica, which can form dense carpets. However, despite its name it is not endemic to Java. Other ground layer species include the fearfully armed nettle Girardinia palmata. Its poisonous spines up to 0.5 cm can inflict a painful sting. Endemic taxa include Alchemilla villosa (Rosaceae), Dioscorea vilis (Dioscoreaceae), Pimpinella prvatjan (Apiaceae), Plectranthus steenisii (Lamiaceae) and Styphelia javanica (Epacridaceae). Cynoglossum javanicum (Boraginaceae) can also be found, but despite its name, it is not endemic and also occurs on Sumatra. On Flores these forests support the local endemic Rhododendron renschianum (Ericaceae), while on Timor they support the local endemic aerial parasite Dendrophthoe timorana (Loranthaceae), which parasitizes both Albizia and Casuarina. On some of the volcanoes there are so-called ‘sand seas’ of virtually unvegetated ash, mainly because it retains very little moister. In the Rujak area, however, short stands of Casuarina have managed to become established in these inhospitable areas. Associated species include various tussock forming grasses and the white, hairy-flowered endemic Styphelia javanica (Ericaceae).
South Malesian Alpine Vaccinium Zone
Between altitudes ranging from about 8000-9000 ft on Java’s Mount Gedeh and Mount Pangerango is a zone largely dominated by species of Vaccinium. Five species occur: Vaccinium coriaceum, V. ellipticum, V. laurifolium, V. lucidum and V. varingiaefolium. This particular group of Vaccinium species has become remarkable polymorphic and can develop as trees, shrubs and lianas. Vaccinium varingiaefolium is particularly versatile having been recorded as a tree, shrub, liana and can grow both terrestrially and epiphytically. However, the trees at this elevation rarely grow to more than about 20 m in height and tend to have knarled, twisted trunks. A tree of some interest is Acer niveum, which can grow near to the summit of these mountains, is the only maple on Java. Other trees include Astronia spectabilis, Eury japonica, Polyosma ilicifolia and Rapanea avensis, although in some upper sections of this zone Vaccinium varingiaefolium occurs almost to the exclusion of other trees. Among the shrubs, Rododendron is a common colourful addition with the yellow flowers of R. cilium, red flowers of R. retusum and orange-red flowers of R. javanicum. Despite its name the latter species is not endemic to Java. Herb layer species include orchids such as Dendrobium hasseltii, the attractive Impatiens platypetala and the parasitic Balanophora elongata. The latter is curious plant with a short red flower-spike and parasitizes both Albizzia and Vaccinium. Other herb layer species are Viola serpens and the near endemic Ranunculus javanicus (Ranunculaceae). Epiphytes are numerous especially ferns of the genus Polypodium such as P. hirtellum, and there are many filmy ferns like the tiny Hymenophyllum paniculiflorum. Mosses are also abundant covering virtually every tree and vine.
South Malesian Alpine Herbaceous Zone
At altitudes of between 7000-8000 ft in a zone frequently enveloped by clouds there is a belt of tender herbs. It appears to be mainly confined to the gap between Mount Gedeh and Mount Pangerango, which is protected from strong winds and is consequently very moist. There are a few trees, but the tree ferns Dicksonia blumei and the endemic Cyathea cernuus (Cyatheaceae) occur, together with the grotesque liana Freycinetia, but it is the rich herbaceous undergrowth that characterizes this zone. The most common species is the pink flowered Impatiens platypetala, but others of this genus such as I. choneceras, I. cyclocoma and I. hirsuta are also encountered. Other common blossoms are Begonia isoptera and Ophiorrhiza longiflora. In places the tall succulent Strobilanthes cernuus forms dense thickets and nearly pure stands of Curculigo curvata occur. Other features include the sweet perfume smell of the ginger Hedychium coronarium.
South Malesian ‘Edelweiss’ Mountain Zone
Above an altitude of about 9400 ft on Java’s Mount Gedeh and possibly in other upland sites is a sparse vegetation zone dominated by the small tree Albizzia montana and shrub Anaphalis javonica (Asteraceae). The latter with its grayish-white flowers is the edelweiss of Java. However, this species is not endemic to Java. It also occurs on Sulawesi and Sumatra. This alpine formation is mostly confined to the lava beds of Gedeh’s old crater, but it is regarded as a pioneer community appearing after other alpine vegetation is burned or otherwise destroyed. Other characteristic species are the dwarf shrubs Gaultheria leucocarpa and Vaccinium varingiaefolium and the endemic tree-shrub Myrica javanica (Myricaceae). Surprisingly ferns, like the adaptable Polypodium feei, and lycopods such as the endemic Lycopodium gedeanum (Lycopodiaceae) are quite common. Other plants are few in number but where water becomes more plentiful small aquatic formation occur. Here the endemic sedge Gahnia javanica (Cyperaceae) can form huge scattered hillocks.
South Malesian (Christmas Island) Forest
On the plateaus and terraces, what appears to be typical evergreen forest occurs with emergent tree up to 45 m. It has a mixture of Indo-Malaysian and Melanesian elements. However, this forest is unique in that the composition and recruitment of plant species is largely controlled by huge numbers of the endemic terrestrial crab Gecarcoidea natalis. The forest floor is almost devoid of leaf litter, seeds and seedlings, since the crabs quickly consume them. It is estimated that there are approximately 100 million of these crabs in the forest. The upper canopy trees comprise Barringtonia recemosa, Cryptocarya nitens, Dysoxylum gaudichaudianum, Inocarpus fagifer and Tristiropsis acutungula, while the typical emergents are Ficus macrocarpa, Hernandia ovigera, Planchonella nitida and Syzygium nervosum. The under storey includes Leea angulata, Ochrosia ackeringae, Pisonia umbellifera and the Christmas Island endemics Arenga listeri (Arecaceae) and Pandanus elatus (Pandanaceae). Shrub layer species include the Christmas Island endemics: Abutilon listeri (Malvaceae), Colubrina pedunculata (Rhamnaceae), Grewia insularis (Tiliaceae) and Pandanus christmatensis (Pandanaceae), and there are various vines like the Christmas Island endemics: Hoya aldrichii (Apocynaceae) and Zehneria alba (Acanthaceae). Other Christmas Island endemics include the fern Asplenium listeri (Aspleniaceae), the orchids Brachypeza archytes, Flickeringa nativitatis, Phreatia listeri (Orchidaceae), other herbs such as Asystasia alba (Acanthaceae), Dicliptera maclearii (Orobanchaceae), Peperomia rossii (Piperaceae), and the grass Ischaemum nativitatis (Poaceae). However, on the more shallow soils of coastal terraces prone to dehydration these evergreen forests give way to a semi-deciduous forest. Here the typical species are Acronychia trifoliolata, Berrya cordifolia, Calophyllum inophyllum, Erythrina variegata, Gyrocarpus americanus, Hibiscus tiliaceus, Kleinhovia hospita, Ochrosia ackeringae, Pisonia grandis, Terminalia catappa and the endemic Pandanus elatus (Pandanaceae).
References
Abdulhadi, R., Srijanto, A. & Kartawinata, K. 1998. Composition, structure and changes in a montane rain forest at the Cibodas Biosphere Reserve, West Java, Indonesia. In: Forest Biodiversity Research, Monitoring and Modeling. Eds. F. Dallmeier and J. A. Comiskey. Man and the Biosphere Series, Volume 40. The Parthenon Publishing Group.
Gillison, A. M. Tropical Savannas of Australia and Southwest Pacific. In: Ecosystems of the World 13 - Tropical Savannas. Ed. F. Bourliere. Elsevier Scientific Publishing Company.
Green, P. T. 1997. Red crabs in rain forest on Christmas Island, Indian Ocean: activity patterns, density and biomass. Journal of Tropical Ecology, 13: 17-38.
Hakim, L., Nakagoshi, N. & Isagi, Y. 2002. Conservation ecology of Gigantochloa manggong: an endemic bamboo at Java, Indonesia. Journal of International Development and Cooperation, 9: 1-16.
Kalkman, C. 1955. A plant-geographical analysis of the Lesser Sunda Islands. Acta Botanica Neerlandica, 4: 200-225.
Leith, H. & Werger, M. J. A. 1989. Ecosystems of the World 14B - Tropical Rain Forests. Elsevier Scientific Publishing Company.
Meijer, W. 1959. Plant sociological analysis of montane rainforest near Tjibodas, west Java. Acta Botanica Neerlandica, 8: 277-291.
Meijer, W. 1976. Botanical Explorations in Celebes and Bali. National Geographic Society Research Reports, 60: 583-605.
Monk, K. A., De Fretes, Y. & Reksodiharjo-Lilley, G. 1997. The Ecology of Nusa Tenggara and Maluku. The Ecology of Indonesia Series. Oxford University Press.
Parks and Reserves: Christmas Island National Park. Australia Government – Department of Sustainability, Environment, Water, Population and Communities. Updated 2010-11-11.
Seifriz, W. 1923. The altitudinal distribution of plants on Mt Gedeh, Java. Bulletin of the Torrey Botanical Club, 50: 283-309.
Smiet, A. C. 1992. Forest ecology on Java: human impact and vegetation of montane forest. Journal of Tropical Ecology, 8: 129-152.
Steenis, C. G. G. J. van. 1972. The mountain flora of Java. Leiden
Steenis, C. G. G. J. van. 1957. Outline of the vegetation types in Indonesia and some adjacent regions. Proceedings of the Pacific Scientific Congress, 8: 61-97.
Watanabe, N. M. & Suzuki, E. 2008. Species diversity, abundance, and vertical size structure of rattans in Bornea and Java. Biodiversity and Conservation, 17: 523-538.
Whitten, T., Soeriaatmadja, R. E. & Afiff, S. A. 1997. The Ecology of Java and Bali. Oxford University Press.
Yamada, I. 1975. Forest ecological studies of the montane Forest of Mt Pangrango, West Java. I. Stratification and floristic composition of the montane rain forest vegetation near Cibodas. South East Asian Studies, 13: 402-426.
Yamada, I. 1976. Forest ecological studies of the montane Forest of Mt Pangrango, West Java. II. Stratification and floristic composition of the forest vegetation of the higher part of Mt Pangrango. South East Asian Studies, 13: 513-534.
Yamada, I. 1977. Forest ecological studies of the montane forest of Mt Pangrango, West Java. IV. Floristic composition along the altitude. South East Asian Studies, 15: 226-251.
Yamada, I. 1990. The changing pattern of vertical stratification along an altitudinal gradient of the forests of Mt Pangrano, West Java. In: The Plant Diversity of Malesia. Proceedings of the Flora Malesiana Symposium commemorating Professor Dr. C. G. G. J. van Steenis, Leiden, August 1989. Eds. P. Baas, K. Kalkman and R. Geesink. Kluwer Academic Publishers.