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A long-term study by Adhi et al. (2020) showed that the groundwater table in oil palm plan- tations ranged from -18 cm to -96 cm in depth throughout the year, and the water content of the 10 cm layer ranged from 332 to 486% (w w-1).
Adaptation strategies and mitigation co-ben-
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be abandoned as soil surface subsidence as a consequence of these activities.
The expansion of agriculture and/or plan- tation in to peatland areas in Indonesia is un- avoidable due to limited availability of mineral soil that can be utilized. Utilization of peatlands for agriculture practices in Indonesia has a long
historical foundation. Traditionally. indigenous people use peatlands to produce traditionally food crops, fruits, and spices, such as the so- nor system in South Sumatera. Starting from the 1980s. they have been growing into large plantations managed modernly to get a better income like oil palm plantations. Besides, other areas have been opened for timber logging and
Land use Area (hectares) %
Forest 6,287,941 47.5
Plantation 1,637,295 12.37
Pulp Plantation 534,832 4.04
Shrubs/bush 2,682,214 20.26
Agriculture land 642,149 4.85
Ex. Mining Concession 8,763 0.07
Paddy field 195,765 1.48
Others 1,252,906 9.22
Total 13,269,705 100.00
Table 7.5. Land cover of Indonesian peatlands
Source: BBSDLP (2015)
Figure 7.8. Snap shot land cover of peatlands: Natural peatlands (top left), Shurbs/uncultivated (top right), Oil palm plantation (bottom left), and Agriculture practices (bottom right)
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Figure 7.9. Peat subsidence with rate 69 cm from 2001 to 2012 (11 years) at Lubug Ogong village, Sei Seki- jang sub-district, Pelalawan Regencyc, Riau Province (left), and fire impact on peat loss (subsidence rate around 30 cm during 7 day fire i.e. 2-8 October 2014) at Jabiren village, Jabiren Raya sub-district, Pulang Pisau Regency, Central Kalimantan Province (right)
- 500.000 1.000.000 1.500.000 2.000.000 2.500.000
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
GHG Emission (Gg CO2e-)
Year
Peat decomposition Peat fire National total
Figure 7.10. Indonesia’s GHG emission trend from peat decomposition and fire compared to national total in year 2000 until 2018 (MoEF 2019)
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land claiming but were then abandoned. How- ever, it is required to be sustainable for which grown water level, wildfire, and biodiversity must be managed appropriately.
Synergies between adaptation and mitigation of peatland management
The impact of climate change and global warming is one of the biggest problems fac- ing of agricultural practices on wetlands today.
Failure to prevent both global warming and climate change can have a very bad impact on agriculture practices on wetlands. In this regard, various efforts and strategies for adaptation and mitigation, both short and long-term anticipa- tion, have been carried out in certain aspects.
This is very important because delaying adap- tation and mitigation efforts to climate change will cause greater losses in the future.
The agricultural sector of the wetland is ex- pected to be able to contribute to dealing with climate change, especially in efforts to reduce greenhouse gas emissions. In this regard, adap- tation must be used as an entry point for miti- gation because farmers do not understand and/
or are not concerned with mitigation actions.
Many emission reduction treatments are bene- ficial for farmers, and conversely, various adap- tation treatments are also able to reduce emis- sions (mitigation as a co-benefits of adaptation).
However, adaptation action can influence miti- gation positively or negatively or vice versa.
The government of Indonesian (GOI) consid- ers climate adaptation and mitigation efforts of agricultural sectors, such as:
• In anticipating climate change, agricultur- al policies should prioritize the principle of adaptation without neglecting mitigation actions. so that every action to reduce GHG emissions in the agricultural sector must also ensure that it supports efforts to in- crease production and productivity.
• Climate change adaptation and mitigation actions must provide benefits in improv- ing the welfare of farmers. so the selected
action must be adapted to the system and people’s agricultural businesses. Adaptation and mitigation actions are operationally de- scribed in each echelon I as well as at the regional level. Thus, the agricultural sector contributes to the national target for reduc- ing GHG emissions.
• Climate change adaptation and mitigation activities are location-specific by taking into account the geographical conditions of each region. so the technology to be ap- plied must be appropriate and location-spe- cific by adopting as much local wisdom as possible.
Several actions of agriculture and plantation activities have synergized between adaptation and mitigation action on peatland such as:
• Improved water management by canal blocking in peatlands is a fundamental step to supporting the sustainable management of peatlands.
• A sustainable alternative for utilizing peat- land with minimum drainage is Aero hydro culture, which basically involves growing crops in peatland under conditions of the lower water table. Maintaining a high wa- ter table in aero hydro culture potentially reduces soil subsidence, fire risk and CO2 emissions.
• The protection of remaining peatlands is one of the most important and cost-effec- tive management strategies for minimising GHG emissions. Currently. the Indonesian government has put a ban or moratorium on the conversion of peatland area. These moratorium could contribute greatly to fu- ture fire prevention and significantly contri- bution to reduce Indonesia’s green house gas emissions.
• Improving physical, chemical, and biological characteristics of peat soil used for agricul- ture practices by amelioration. Ameliorant use can be organic or inorganic materials.
Theoretically, the ideal material used for im- Wetland Agriculture
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proving peat soil characteristics is that has high base saturation, can increase peat pH, and contains complete nutrients, so it can also work as a fertilizer and has the ability to improve the structure of peat soils. The type of ameliorant that has been widely used for agriculture practices are volcanic ash, lime, and mineral soils. wood/litter ash, biochar, and animal manure. The characteristics of ameliorant materials for peatlands and their function in adaptation and mitigation to GHG emissions that are commonly used are:
• Lime/dolomite function: to reduces organic acids’ toxicity, increases soil pH and base saturation, and mitigates GHG emissions.
• Animal manure function: to increase nutrient availability and soil stability, and mitigation GHG emission
• Biochar function: toreduces soil acidity
and mitigation GHG emission
• Mineral soil function: to reduce toxicity of organic acids and mitigation GHG emission
• Pugam (peat fertilizer) function: to reduce toxicity of organic acids, increase nutrient availability and mitigation GHG emission