The utilization of swampland or agricultural cultivation, especially food crops (rice) has been carried out for a long time. With the increasing need for swampland products and the develop- ment of management technology, swampland has also developed for several commodities such as annual food, horticulture crops, planta- tion crops, as well as fisheries, and livestock. The management of swampland for annual crops, perennial horticultural, and plantation crops will be discussed further.
Island
Swampland typology (million hectares)
Total Tidal swampland Freshwater swampland
Mineral Peat Mineral Peat
Kalimantan 0.567 0 2.684 0.176 3.427
Sumatera 1.656 0.173 3.620 1.402 6.851
Sulawesi 0.010 0 0,671 0 0,681
Papua 0.286 0.032 1.819 1.082 3.219
Maluku 0.011 0 0.087 0 0,098
Total 2.530 0.205 8.881 2.660 14.276
Table 7.1. Potential area of swampland for rice field
Source: BBSDLP (2015) Wetland Agriculture
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Swampland management for rice
The management of tidal swampland for rice is still mostly done traditionally based on local knowledge and local wisdom. Generally, farmers grow local rice varieties with a long life cycle of about 9-10 months, so that only one crop cycle can be cultivated annually. With the Green Rev- olution which was started in the late 1960s in In- donesia, new high-yielding varieties were intro- duced. Recently Inpara 2, Inpara 3, Mekongga, and Ciherang have been introduced on acid-sul- fate tidal swampland (Simatupang et al. 2017).
Several other varieties have also been reported (Mamat and Sukarman 2020). However, local varieties are still maintained by the communi- ties. The slender shape and tender taste of rice, high adaptability, relatively high resistance to pests and diseases, and the higher selling price compared to high yielding varieties have caused local farmers to still cultivate them, despite the relatively low yield of 3-4 tonnes ha-1(REF).
Peatland is a type of soil that has long been used by the community to produce food crops.
Shallow peat (< 100 cm thickness) can be utilized
for annual crops including rice (Noor et al. 2017).
Water and soil fertility management are critical for the success of peatland farming (Nusyamsi et al. 2020; Noor and Sosiawan 2020).
Swampland management for other annual crops
In the program to increase the production of national food crops, corn and soybeans are food crops that are cultivated in swampland oth- er than rice. According to, Maize and soybeans can be cultivated on tidal swampland both on mineral and peat soil, on types C and D swamp- lands towards the end of the rainy season and during the dry season (Simatupang et al. 2017).
Planting in the dry season requires water man- agement by applying a block system called dam overflow (locally called tabat) to maintain the groundwater level. In type B, maize and soybean can still be planted with the raised-bed (surjan) system after the rice harvest in the dry season.
Various vegetable crops (spinach, celery, long beans, cucumbers, chilies, and tomatoes) and fruits (oranges, papaya, bananas, and rambutan)
No Ordo Sub order/great group Land typology Area (hect-
ares) Proportion (%)
1 Entisol Sulfaquent/Typic Sulfaquent Acid sulphate Potential 1,132,750 3.39
Sulfaquent/Histic Sulfaquent Potential acid sulphate associated with peat 66,000 0.20 Sulfaquent/Haplic Sulfaquent Potential acid sulphate associated with silty saline 997,430 2.99 Sulfaquent/Hydraquent/Haplic
Sulfaquent Potential acid sulphate associated with saline 2,127,800 6.37
2 Inceptisol Sulfaquept/Haplic Sulfaquept Actual acid sulphate associated with saline 2,374,000 7.11
3 Histosol**) Saprist Shallow peat 5,241,437 35.16
Saprist- Hemist Mediun peat 3.915.291 26.27
Hemist-Fibrist Deep peat 2,763,475 18.54
Fibrist Very deep peat 2,985,371 20.03
Total***) 21,603,554 100.00
Table 7.2. Soil types on swampland
Source: processed from *) Nugroho et al. 1992 and **) BBSDLP (2011); ***) not including the mineral soil in freshwater swamp 13.28 million ha.
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are commonly grown on swamplands. Horticul- tural crops generally require a growth medium that is fertile, loose, contains lots of humus, has a pH of 5.5-7.0, and is not flooded. Meanwhile, swampland is very different from the conditions required by the requirements for growing horti- cultural crops. Therefore, the cultivation of horti- cultural crops in swampland requires technolog- ical innovations in the form of land preparation and arrangement, water management, adaptive types and varieties, amelioration, fertilization, and post-harvest.
The land arrangement is carried out by apply- ing a raised-bed or gradual surjan (locally called tukungan) system. This system also functions as water management, coupled with an increase in water quality by adding lime or dolomite to the water which functions to increase pH, increase Ca and Mg concentrations, and reduce Fe con- centrations, while increasing plant productivity (Raihana and Koesrini 2017). Application of Ca and Mg through dolomite (Ca-MgCO3) can actu- ally improve the quality of citrus fruits, including taste because it increases sugar and acid levels, and vitamin C (Antarlina and Noor 2011).
The application of rice husk biochar enriched with agricultural waste compost in swampland increased soil pH, reduce Fe toxicity, reduce methane (CH4) emissions, and increased grain
yield by 28%. As a soil amendment, biochar can act as an atmospheric carbon sink due to the conversion of bio-degradable carbon (biomass) into less degraded aromatic carbon (biochar) (Annisa et al. 2021).
Swampland management for annual crops Swampland with mineral soil and deep peat soil (2-3 m thick peat) can be utilized for peren- nial crops. Annual crops that are cultivated and are in great demand in swampland are oil palm and rubber. Both of these plants are reported to grow well on peat with medium thickness (1-2 m), while coffee and cocoa can grow on shallow peat (0.5-1 m). According to Sabiham and Sukar- man (2012) oil palm is a commodity that is able to adapt well to peatland. By applying appropri- ate water management technology, along with increasing the stability of peat material and CO2 absorption by plants in oil palm development areas, the utilization of peatland will provide great benefits, not only for the present but also for the future.
Currently, the utilization of swampland for annual crops such as oil palm is mostly directed at degraded peatland. Technology to increase productivity is needed through water manage- ment, amelioration, fertilization, the use of de- composers, and cropping systems to increase the productivity of annual crops on peatland.
Figure 7.2. Raised-bed system for growing chili on medium freshwater swampland at Banjarbaru Experimen- tal Station, September 2019
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Water management in oil palm cultivation on degraded peatland is more problematic than on mineral soil because if it experiences drought it is irreversible, so its ability to hold water is reduced (Sosiawan et al. 2021). Water management must be able to create favorable conditions for vari- ous chemical reactions in the soil, wash out tox- ic elements, and slow down the process of peat subsidence. Therefore, water management is the key to increasing oil palm productivity. The best growth and productivity are obtained if the water level can be maintained at 60-80 cm from the soil surface.
The low productivity of oil palm on degraded peatland is due to low soil fertility and soil bio- logical properties that are unfavorable for plant growth. Therefore, soil amelioration is needed to improve the chemical and biological proper- ties, so that it can increase oil palm productivity by 0.34-0.61 tons ha-1 month-1 (Masganti et al.
2019). Now, oil palm plantations in Indonesia reached 9.7 million ha, of which 2.0-2.5 million ha are in swampland. The average productivity of oil palm in swampland is low, but with tech- nological innovation, it can be obtained 20 – 24 tons of FFB ha-1 year-1 (10 years old). Oil palm productivity on peatlands was 19-25 tons FFB ha-1 year-1 (Noor 2001; Noor 2004).
Swampland management for livestock Livestock can be carried out on swampland, both tidal swampland, and freshwater swamp- land, and need to be matched to its land char- acteristics. Poultry can be cultivated in swamp- land, especially ducks and chickens, as well as for ruminants, namely cattle and buffalo. Taking care can be done either extensively or inten- sively depending on the scale of business, wa- ter depth, and type of livestock. An important aspect that needs to be considered is the ade- quacy and quality of feed. In tidal swampland, drinking water for livestock should be provided from well water instead of from drains to reduce sour taste and improve quality.
Cattle rearing on both tidal and freshwater swampland is carried out intensively due to
natural conditions that do not allow them to be released into the wild. However, if there is open land where the soil is dense enough, livestock can be released for several hours to train their muscles and get enough sunlight (Rohaeni et al.
2017). Management integration between plan- tation crops and livestock has long been recom- mended, such as between oil palm and cattle to be more efficient and more profitable (Noor 2016).