name of organic soil in Indonesia is called Organosol, which consists of Fibrist,
Hemist, and Saprist (Subardja et al. 2014).
All peat soils in Indonesia are commonly water-saturated as the region where peat
occurs has wet climates, with annual rainfall between 2500 and 5000 mm. Water
plays an essential role in the preservation of organic matter. Furthermore, the acidic
water halts peat decomposition. Innately, peat-forming organic matter is stable and
resistant to biological decomposition under a water-logged environment.
16.4 Distribution and Types of Tropical Peats
Major peats in Indonesia are distributed in Sumatra, Kalimantan, and Papua. Only a
few peats are found in Sulawesi and Java (Wahyunto et al. 2010; Nugroho et al.
2014). The climate of this region is mostly a monsoon system, and some substantial
peats occur in the region of the anti-monsoon system. The monsoon climate shows
visible differences between wet and dry months, between November and April, and
May and October. The anti-monsoon climate has no distinctive differences between
wet and dry months, while the semi-monsoon climate has two peaks of rainy
seasons, at the beginning and the end of the year. Dry months have a daily average
of rain between 0 and 3.33 mm, while wet months have a daily average of over
13.3 mm rain (Kuswanto et al. 2019). The present peat distribution in Indonesia
occurs in all these three climate systems.
The total area of tropical peat globally is about 441 million hectares. Three major
centers of tropical peats are Southeast Asia, South America, and Africa (Rieley et al.
2016). The estimates of tropical peat areas in Indonesia range from 13 to 27 million
hectares. Recently, the government of Indonesia mapped the region and found that
the total area of tropical peats is 13.4 million hectares, and the peat thickness reached
more than 7 m in Sumatra and Kalimantan (Personal Communication, Sofyan
Ritung, 2020).
Types of tropical peatlands in Southeast Asia are divided into five as follows:
1. Brackish (Mangrove) and coastal peats [Mangrove tree];
2. Riparian peat, and sub-coastal and inland peats [Mangrove, and freshwater forest
trees];
3. Flood plain peat [Freshwater forest trees];
4. Kerapah peat [Heath forest];
5. Montane and alpine peat [Grass and sedge ferns].
Some detail description of tropical peat types is presented in Table 16.1.
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G. Anshari
Hemist, and Saprist (Subardja et al. 2014).
All peat soils in Indonesia are commonly water-saturated as the region where peat
occurs has wet climates, with annual rainfall between 2500 and 5000 mm. Water
plays an essential role in the preservation of organic matter. Furthermore, the acidic
water halts peat decomposition. Innately, peat-forming organic matter is stable and
resistant to biological decomposition under a water-logged environment.
16.4 Distribution and Types of Tropical Peats
Major peats in Indonesia are distributed in Sumatra, Kalimantan, and Papua. Only a
few peats are found in Sulawesi and Java (Wahyunto et al. 2010; Nugroho et al.
2014). The climate of this region is mostly a monsoon system, and some substantial
peats occur in the region of the anti-monsoon system. The monsoon climate shows
visible differences between wet and dry months, between November and April, and
May and October. The anti-monsoon climate has no distinctive differences between
wet and dry months, while the semi-monsoon climate has two peaks of rainy
seasons, at the beginning and the end of the year. Dry months have a daily average
of rain between 0 and 3.33 mm, while wet months have a daily average of over
13.3 mm rain (Kuswanto et al. 2019). The present peat distribution in Indonesia
occurs in all these three climate systems.
The total area of tropical peat globally is about 441 million hectares. Three major
centers of tropical peats are Southeast Asia, South America, and Africa (Rieley et al.
2016). The estimates of tropical peat areas in Indonesia range from 13 to 27 million
hectares. Recently, the government of Indonesia mapped the region and found that
the total area of tropical peats is 13.4 million hectares, and the peat thickness reached
more than 7 m in Sumatra and Kalimantan (Personal Communication, Sofyan
Ritung, 2020).
Types of tropical peatlands in Southeast Asia are divided into five as follows:
1. Brackish (Mangrove) and coastal peats [Mangrove tree];
2. Riparian peat, and sub-coastal and inland peats [Mangrove, and freshwater forest
trees];
3. Flood plain peat [Freshwater forest trees];
4. Kerapah peat [Heath forest];
5. Montane and alpine peat [Grass and sedge ferns].
Some detail description of tropical peat types is presented in Table 16.1.
466
G. Anshari