Forest Types – Forests in Latin are called sylva, sylvi or sylvo. Sylva, sylvi or sylvo which means a very wide place. An area is considered forest if it has an area of more than 1/4 ha and a number of trees grow there, as well as the presence of interdependent biotic and abiotic factors.
In general, the concept of a forest is a place inhabited by dense trees. Such as shrubs, grasses, mushrooms, ferns, trees and other plants on a large scale. In Indonesia, forests have different names depending on their respective regions, such as utan in Jakarta, leuweung in Sundanese, alas or wana in Java, etc.
According to the law of numbers. 41 of 1999, forest is an ecosystem unit in the form of expanses of land containing biological natural resources because trees dominate the natural environment and their relationship with one another cannot be separated.
Furthermore, the largest area of forest land is in Papua with an area of 32.36 million hectares. The second order belongs to Kalimantan with an area of 28.23 million hectares, then Sumatra with an area of 14.65 million hectares, Sulawesi with an area of 8.87 million hectares, Maluku and North Maluku with an area of 4.02 million hectares. Forests in Java with an area of 3.09 million hectares, Bali and Nusa Tenggara with an area of 2.7 million hectares.
Forests are habitats for plant and animal species, where carbon dioxide is recycled into oxygen, where hydrological flows are regulated, where water and soil are conserved, and forests are of great environmental importance. Sinaumed’s friends need to know the types of forests in Indonesia and their benefits. Moreover, most of the large islands of Indonesia have vast forests. No wonder Indonesia is often referred to as the lungs of the world.
But lately there have been many forest fires that have caused various damages. Community and government efforts to protect forests are of course very much needed to maintain forest sustainability. Moreover, there are many types of forests in Indonesia.
The types of forests in Indonesia and their benefits are important for Sinaumed’s to study. When people know the importance of forests for life, people will certainly care more about the surrounding environment. In addition, forests also play an important role as a place to provide oxygen for human respiration.
For more details, here we have to study the definition of forest first, before discussing the types of forests in Indonesia and their functions.
Definition of Forest
Forest is land dominated by trees. Hundreds of definitions of forest are used worldwide, incorporating factors such as tree density, tree height, land use, legal status, and ecological function.
The United Nations Food and Agriculture Organization defines forest as a land area extending over 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10% or trees capable of reaching these thresholds on the spot.
This does not include land that is predominantly agricultural or urban use. Using this definition, the 2020 FRA found that forests covered 4.06 billion hectares, or about 31% of global land area in 2020.
Forests are the dominant terrestrial ecosystems on Earth and are distributed throughout the world. More than half of the world’s forests are found in only 5 countries (Brazil, Canada, China, the Russian Federation and the United States). The largest share of forest (45 percent) is found in the tropics (rain forest), followed by temperate and subtropical boreal regions.
Forests account for 75% of the total primary production of the Earth’s biosphere and contain 80% of the Earth’s vegetative biomass. Net primary production is estimated at 21.9 gigatons of carbon per year for tropical forests, 8.1 for temperate forests and 2.6 for boreal forests.
Forests at different latitudes and altitudes with varying amounts of rainfall and transpiration form very different biomes, namely:
boreal forests around the Arctic, tropical rainforests and dry forests around the equator, and temperate forests in the mid-latitudes.
Areas at higher altitudes tend to support forests similar to areas at higher latitudes and rainfall also affects forest composition.
Almost half of the forest area (49 percent) is relatively intact, while 9 percent is fragmented with little or no connectivity. Tropical rainforest and boreal coniferous forest are the least fragmented while subtropical dry forest and oceanic temperate forest are among the most fragmented.
About 80 percent of the world’s forests are located on more than 1 million hectares of forest, the remaining 20% are located on more than 34 million parcels of land worldwide, most of which are less than 1,000 hectares.
Humans and forests influence each other positively and negatively. Forests provide ecosystem services for humans and can also become tourist attractions. Forests can also affect human health. Human activities, including the unsustainable use of forest resources, can have a negative impact on forest ecosystems.
In Indonesia, according to Forestry Law No. 41 of 1999, forest is an ecosystem unit in the form of a stretch of land that contains biological natural resources because trees dominate the natural environment and cannot be separated together.
Forest Types in Indonesia
In order to understand clearly, the following types of forests in Indonesia have been summarized by sinaumedia.com from various sources:
Forest Types Based on Biogeography
The Archipelago is a natural relief formed from the confluence of three land plates. Even today, the three plates of the earth are still approaching. As a result, among other things, earthquakes often occur in this island nation.
The history of the formation of islands in the equatorial belt has formed three main biogeographical regions, namely: the Sunda Shelf, Wallacea and the Sahul Shelf. Each biogeographic region reflects the distribution of life forms based on differences in the physical surface of the earth.
Sunda Shelf (in the western part)
The Sunda Plateau is a strip of land that extends from the east (mainland Asia) and lies west of the Wallace Line. Wallace’s line is an imaginary dividing line between the flora and fauna of the Sunda Plateau and the easternmost part of Indonesia. This route is from north to south between Kalimantan and Sulawesi, and between Bali and Lombok. This lineage is named after the biologist Alfred Russel Wallace who in 1858 showed that the distribution of flora and fauna in Sumatra, Kalimantan, Java and Bali was closer to mainland Asia.
Sahul Shelf Area (in the eastern part)
The Sahul Shelf is a strip of land that has shifted from the Australesian territory and lies east of the Weber Line. The Weber line is an imaginary dividing line between flora and fauna between the Sahul Shelf and the westernmost part of Indonesia. The line runs from north to south between the Maluku Islands and New Guinea and between East Nusa Tenggara and Australia. This lineage is named after the biologist Max Weber, who around 1902 showed that the distribution of flora and fauna in this area was closer to mainland Australia.
Wallace Region / Deep Sea (in the middle)
The earth plate on the outskirts of East Asia moves between the Wallace and Weber lines. This area includes Sulawesi, the Lesser Sunda Islands (Nusa Tenggara), and the Maluku Islands. Most of the flora and fauna in this area are endemic (found only in the area concerned and not found anywhere else in the world). However, the region also has elements of the Eastern Sector and the Australasia Region. Wallace suggested that the sea was covered with ice during the Ice Age so that plants and animals from Asia and Australia could interbreed and congregate on the islands. Although Asian flora and fauna are still more abundant in the western part and Australian flora and fauna in the eastern part, this is because the Wallace area used to be a very deep sea trench, so that the flora and fauna of plants were difficult to pass and stopped spreading.
Forest Types Based on Climate
Because of its location at latitude, Indonesia actually has a tropical climate. However, its location between two continents and between two oceans makes the climate of this archipelago even more diverse.
Based on a comparison of the number of dry months with the number of wet months per year, Indonesia has three climate zones, namely:
- Climate type A (very humid) , where the peak of the rainy season falls from October to January, sometimes until February, this region covers the island of Sumatra; Borneo; the western and central parts of the island of Java; west of the island of Sulawesi.
- Climate Type B (wet) has a peak rainy season between May and July and August or September being the driest months. This area covers the eastern part of Sulawesi Island; Moluccas; most of Papua.
- Climate type C (slightly dry) has less rainfall, while dry months last longer. This area includes East Java; part of Madura Island; Bali Island; Nusa Tenggara; the southern tip of Papua.
Based on the existing climate differences, Indonesia has peat forests, tropical rain forests, and monsoon forests.
1. Tropical Rain Forest
The earliest forest type in Indonesia is tropical rain forest. Tropical rainforests are widely recognized as a type of forest in Indonesia because the Indonesian archipelago receives a lot of sunlight, has high rainfall, and high average temperatures.
The characteristics of tropical rain forests in general:
- Plants that live in tropical rain forests are generally classified as plants with large, tall and dense leaves that grow tightly.
- The animals that live in tropical rain forests are very diverse because they are divided into 3 areas, each forest is home to different animals. For example, in tropical forests in the western region, animals that develop are mainly large-bodied animals such as tigers, elephants, giraffes and others. This is because the tropical rain forests in the eastern region are dominated by small animals and various types of birds typical of Papua. Meanwhile, for the tropical rain forest in the transition zone, there are many unique animals such as anoa, wild boar and several medium-sized mammals.
- In addition, another feature of tropical rain forests is the relatively high rainfall, which makes mixed soils very fertile.
The benefits of tropical rain forests can be as a breeding ground for rare plant and animal species as well as as a water reservoir during the dry season.
2. Monsoon Forest or Seasonal Forest
Monsoon forests grow in areas with climate categories C or D, namely in Central Java, Yogyakarta, East Java, Bali, NTB, parts of NTT, southeastern Maluku and parts of the southern coast of Irian Jaya. Tree species in this forest include teak (Tectona grandis) , walikukun ( Actinophora fragrans) , eucalyptus (Eucalyptus alba) , sandalwood (Santalum album) and eucalyptus (Melaleuca leucadendron) .
It is called seasonal forest or monsoon forest because it has quite clear differences in conditions between the rainy season and the dry season. Plants in the dry season forest often wither, and during the rainy season grow back massively. Here are some characteristics of monsoon forests or monsoon forests:
- Can be found in the highlands and lowlands. – The distance between trees in seasonal forests tends not to be tight, in fact they are very neatly spaced with a certain distance.
- The height of the trees that fill the forest this season is not too high. Not like a rainforest.
- Animals that live in the forest this season are not as numerous and as aggressive as those that live in tropical rain forests. The average animals that can be found are insects, snakes, birds and several types of mammalian rodents.
The benefits of seasonal forest are as a production forest and as a tool for climate and seasonal indicators
3. Peat Forest
Peat forests are in climate category A or B, namely on the east coast of Sumatra, along the coast and major rivers in Kalimantan and in most of the south coast of Papua.
Peat forests are tropical hardwood forests where the wetlands prevent the leaves and wood from completely decomposing. Over time, an acidic layer of peat forms. Peat forests are often surrounded by moist forest on non-flooded land and surrounded by mangroves in brackish water.
Exploitation of peat forests carried out by the Indonesian government in Kalimantan’s peat forests for agricultural purposes has caused many fires to occur in peat forests.
Major fires occurred in 1997-1998 and 2002-2003. A study by the European Space Agency shows that peat forests have the ability to sequester the planet’s carbon. The 1997-1998 fires released up to 2.5 billion tons of carbon and the 2002-2003 fires released between 200 million and 1 billion tons of carbon into the Earth’s atmosphere.
Oil palm plantations in Kalimantan play an important role in draining peat forests which causes the release of carbon from peatlands. Conserving peat forests is known to prevent the release of more carbon per unit area than preventing deforestation and lowers costs. Indonesia has 50% peat forest in the tropics and 10% peat forest in the world.
Forest Types Based on Soil Characteristics
Based on the nature of the soil, forest types in Indonesia include coastal forests, mangrove forests and swamp forests.
1. Beach Forest
Coastal forest or more precisely called coastal vegetation or sandy beach vegetation (English: vegetation beach) is a ground cover that grows and thrives on sandy beaches above the highest tide line in the tropics. Traditionally, experts distinguished two and sometimes three plants that formed in the area.
Although it is quite rich in fauna diversity, only certain types of animals are unique to this type of ecosystem. Most of these animals also live in other types of ecosystems, or even only come to coastal forests for short periods of time.
2. Swamp Forest
The next type of forest in Indonesia is swamp forest. Swamp forest is a type of forest in Indonesia. Swamp forests cover forest areas with various plants such as beluntas, pandanus and ketapang. This type of forest is mostly found on the east coast of Sumatra, West Kalimantan and Central Kalimantan. The characteristics of peat swamp forests in Indonesia are:
- The land is always flooded to form swamps
- Peat swamp forest also has a layer of soil in the form of peat soil.
- Plants that can live in peat swamp forests are often small in stature and have less strong roots than those that grow in dense soil.
3. Mangrove Forest
The next type of forest in Indonesia is mangrove. Mangroves grow on steep, muddy beaches which are always exposed to sea tides. Mangroves are home to many species of fish and shrimp. So, this mangrove forest is very important for the environment. Here are some of the benefits of mangroves as a type of forest in Indonesia:
- As a breakwater and restraint.
- As a natural habitat for small fish.
- As an anti-abrasion caused by sea water.
Forest Types Based on Tree Types
The types of forests in Indonesia and their benefits can also be seen based on the type of tree, as follows:
1. Heterogeneous Forest
Heterogeneous forest is a forest where many types of trees grow, for example wilderness. Usually in tropical areas with high rainfall such as Central and South America, Africa, Southeast Asia and Northeastern Australia, the trees are tall and broadleaf. In Indonesia, heterogeneous forests are found on the islands of Java, Sumatra, Kalimantan and Papua.
2. Homogeneous Forest
Homogeneous forest is a forest where only one type of tree grows. In general, homogeneous forests are created for specific purposes, such as for reforestation, afforestation or industrial expansion. Examples of homogeneous forests include teak and pine forests.
Author: Ziaggi Fadhil Zahran