Peatlogy in tropical peatland: A new transdisciplinary science
The Earth Anomaly – climate change, global warming, and ecological and environmental (E&E) degradation of land – presents a complex existential crisis for mankind. Based on field studies in tropical peatlands, Professor Mitsuru Osaki and his collaborators have developed an innovative transdisciplinary peatland science – Peatlogy – to address this complexity. Peatlogy in tropical peatland offers a holistic approach that aims to develop: (1) new knowledge of how plants adapt to extremely poor nutrients and low-oxygen conditions; (2) tools for creating an inventory of ecosystem assets, including water, carbon, and nutrients; (3) approaches for eco-management and eco-evaluation; and finally, (4) nature-based approaches for land surface management (eg, storage-based water management, AeroHydro culture).
The Earth Anomaly – climate change, global warming, and ecological and environmental (E&E) degradation – looms large over humanity. Researchers across the world and the breadth of scientific disciplines have proposed countless approaches to fix our broken planet, or failing that, to mitigate the consequences of our collective folly. However, Earth Anomaly issues are highly complex, and single-perspective approaches cannot capture the full spectra of causes, impacts, and injured parties (Sulaiman, A, et al, 2023). Earth Anomaly has had a terrible influence on tropical peatland and is exacerbated by poor management of tropical peatland (Wijedasa, LS, et al, 2016).
To date, most measures proposed have been Industrial Technology-based solutions (ITbS) and industrial Nature based Solutions (iNbS, renewable energy apparatus) – harnessing the power of technology to reduce specific impacts of climate change. Such approaches are often expensive, resource intensive, and relatively ineffective, following E&E-degradation. Now, researchers and decision-makers are increasingly looking for Nature-based Solutions (NbS) that harness and support existing natural capital (Fig 1). Such NbS are often simple and low-cost, as well as effective and reliable. For example, instead of providing cooling systems based on air conditioners and/or water misting (expensive, energy intensive, with potential public health risks), tree planting can cool the air by removing latent heat (via evapotranspiration), green albedo, and creating shade, while also acting as a carbon sink, energy store, and water reservoir in the ground (Fig 2). Thus, trees have a key role in Nature-based Solutions. However, in Nationally Determined Contributions (NDC) reported to UNFCCC until October 2021, NbS was contaminated with industrial Nature-based Solutions (iNbS) such as photovoltaic generation and wind power generation, which are not effective or efficient in the tropics and cause devastating ecosystem destruction (deforestation), resulting in serious environmental pollution.
As a unique and complex ecosystem, tropical peatland is carbon-water rich, but also fragile and nutrient-poor. Based on the features of tropical peatland, Professor Mitsuru Osaki from Hokkaido University in Japan and a team of collaborators are developing an innovative transdisciplinary peatland science – Peatlogy. Central to this approach is the ‘Trilemma’ model, in which the Earth’s ecology, environment, and resources take on a Venn structure. The overlapping spaces between the three form the realms of ecological destruction, environmental pollution, and resource depletion, creating a ‘trilemma’ of damage; human beings sit at the triple junction.
Peatlogy integrates various sub-disciplines used to study the biosphere, rhizosphere, geosphere, and hydrosphere (eg, geology, geophysics, geography, meteorology, atmospheric science, etc) with those focused on human behaviour (eg, economics, agricultural science, social and cultural studies). In this way, Peatlogy aims to capture the full array of interactions, cause-and-effect relationships, functions based on structures and elements, networks and feedback systems that control environmental change. The goal is to identify and apply appropriate true NbS (not including iNbS) to address E&E degradation issues in tropical peatland.
To build Peatlogy, Osaki and his colleagues are seeking to understand a series of paradoxes of tropical peatland, defining new geosystems, taking an inventory of ecosystem assets, developing new approaches for eco-monitoring and evaluation, and proposing approaches for nature-based eco-management.
Peatland paradoxes
Peatlands have low oxygen and extremely poor nutrients in the peatland surface but, paradoxically, support some of the richest and most diverse ecosystems on Earth. To achieve this, plants have developed unique aerial root systems that absorb oxygen, fix nitrogen from the air, and uptake other nutrients such as phosphorus decomposing litter in mound. Osaki and colleagues have applied the lessons learnt from this paradox to develop new peatland management techniques, such as AeroHydro culture.
Researchers and decision-makers are increasingly looking for Nature-based Solutions (NbS) that harness and support existing natural capital.Other paradoxes relate to human perceptions and management of peatland nature. For example, forests remove carbon from the atmosphere, regulate water balance, cool the air, and store energy. However, they are rarely credited with such services.
TREE (Forest) has function of solar energy utilisation or mitigation on 1) carbon assimilation energy through photosynthetic process (around 0.1%), 2) green spectrum reflection (around 10% solar energy reduction), 3) evapotranspiration energy as latent heat removal, contributed to air cool down and water cycle (large portion of solar energy consuming, probably more than 50%), indicating that TREE (Forest) relate with Latent Heat/Sensible Heat balance (eg, 10°C increase in air without forest, see Fig 3 [Osaki et al, 2024]).
Instead, humans forge ahead with solar panels, water dams, air conditioners, and fossil fuel consumption, despite some estimates suggesting that the cost of forest natural capital is approximately 100–1,000 times cheaper than the equivalent technological solutions (Hojo, et al, 2021).
Latent heat/ sensible heat
According to actual measurements of the heat balance in tropical peatlands, the heat balance sheet is totally different between pristine forest and non-forest (grass and shrub). Latent heat and sensible heat are dominant in forests and non-forests, respectively (Fig 3). Thus, forests cool the air by removing latent heat (evapotranspiration by solar energy) and reflecting green light (Fig 2). Latent heat also relates to the water cycle, because gas-formed water due to latent heat is transported into the lower atmosphere layer.
The gas-formed water is then transformed into liquid-formed water release heat, from which droplets precipitate to the forest. An essential role of forests is the assimilation of carbon (CO2 removal from air); however, the cooling-down and water-cycling function of forests unfortunately attracts less attention, even in the discussion of global warming. Industrial technologies cannot perform all of these roles. Solar cells, for example, produce electric energy but cannot cool air (in fact, they may make it hotter) or negatively affect the water cycle (they may have a drying effect) and do not protect against land erosion.
Ecosystem assets
Much like accounting in economic disciplines, natural capital provides important asset classes, including water, carbon, and nutrients, which form the basis of life on Earth, and drive economic development and wealth accumulation. However, Osaki and his team argue that, unlike traditional economic approaches, these asset classes should be managed through a reliable stewardship system and not exploited beyond repair.
Nutrients, as a natural asset, are largely minerals and chemical compounds found in soils, plants, and water. Osaki’s team propose that water assets cycle through a variety of reservoirs and pathways (surface water, groundwater, oceans, evapotranspiration, precipitation, etc). Carbon assets are stored in fossil fuels (‘black carbon’), plants (‘green carbon’), peat (‘gold carbon’), permafrost (‘silver carbon’), and seas/oceans (‘blue carbon’).
Under a balanced natural system, cycles of nutrients, water, and carbon are intricately linked and ultimately driven by solar energy. Forests offer significant potential for the stewardship of all three natural assets. Trees harness solar energy through photosynthesis, where they absorb CO2 from the atmosphere and store carbon-based energy for future use. Trees regulate the water cycle, modulating its passage through the environment; by providing shade and undergoing evapotranspiration, trees have a cooling effect, together with a green-albedo effect. Trees also provide materials for soil development, thus contributing to nutrient recycling (Fig 2).
Under the capitalist economic model, this delicate balance is disturbed. For example, a finished wooden product is given a quantifiable economic value, while the raw material (the forest) and its intricate network of assets and processes are not. Peatlogy aims to change this approach, by recognising and quantifying the full value chain of natural assets, facilitating their use in true NbS (tNbS) and Natural Capital Concept.
Eco-evaluation approaches
Quantifying natural assets, systems, and cycles requires the right toolset, and Peatlogy draws on a variety of disciplines and approaches, the majority of which rely on satellite data collection supported by ground truth studies. In simple frameworks (known as Tier 1 methods), the activity of a given variable is multiplied by a standard factor to estimate dynamic changes across a system. For example, the total area of vegetation cover is multiplied by an average carbon storage coefficient to estimate the carbon stock in an area of forest. However, the integration of different data streams is important, as different variables are interdependent.
Over the course of the 20th century, as economic activities began to impact natural spheres more severely, mutual conflicts (or ‘lemma’) arose. There was a shift to a trilemma state. In a trilemma state, the environment, ecology, and resource spheres overlap, taking the form of a three-way Venn diagram, showing that there is ecological destruction between the ecology and environmental spheres; between the environment and resource spheres there is environmental pollution; and between the ecology and resource spheres is resource depletion. Finally, at the centre of all three spheres lies the human dimension. During the first decades of the 21st century, the trilemma model branched into two zones: the Global North insisted on industrial Technology-based Solutions (iTbS), known as ‘trilemma’. The global South (or more accurately the Global Central region including the equatorial belt and tropical/subtropical zones) depended on true NbS (tNbS), known as ‘triharmony’.
Therefore, under Tier 3 approaches, the spatial distribution of data is considered and more complex models are employed, allowing multiple variables to be considered at the same time. For example, carbon stocks in a forested area can be more accurately determined by inputting the horizontal and lateral distributions of different vegetation types, soil and water distributions, and land management interventions across the study area.
One such Tier 3 system is iMRV (integrated Monitoring, Reporting, and Verifying), which uses a network of satellite, aerial vehicle, and ground-based sensors operating across different spatio-temporal scales and various parts of the electromagnetic spectrum to track dynamic changes in biomass, the water cycle, and the carbon cycle. For example, by mapping vegetation cover and vegetation type, iMRV can identify areas of deforestation and slash-and-burn farming, with the observations supported by ground truth data collected using unmanned aerial vehicles (UAVs).
The system also creates detailed digital elevation models (DEMs), allowing researchers to identify geomorphological changes related to environmental degradation. For example, the ground surface level rises and falls with changes in groundwater level. When peatland desiccation (moisture removal) occurs, peatland subsistence can be measured by iMRV using satellites, aerial vehicles, and ground-based surveys.
Peatlogy aims to capture the full array of interactions, cause-and-effect relationships, structures and networks, and feedback systems that control environmental change.iMRV can be used on global scales, and the resolution can be better than 100m2. In tropical areas, iMRV is complemented by other satellite-based observation systems, including iEOS (informatics on Equator Observation System), which collects data from along the Equator, allowing for the measurement of numerous pertinent variables, including soil moisture, soil organic carbon (SOC), carbon and methane fluxes, chlorophyll fluorescence, and vegetation type. When iEOS satellites are launched from the equator orbiter, critically iEOS has a temporal frequency of several times per day, which addresses a major issue with remote sensing in tropical regions: cloud cover (Fig 4).
Drainage-based water management (drainage-based WM): Conventional ‘drainage-based’ WM in tropical peatland is designed to drain water from the ecosystem as quickly as possible. A central canal is constructed down the slope of the peat dome, with secondary canals branching off along contour lines. Water then drains into the secondary canals, which in turn drain into the primary canal.
Stock-based water management (stock-based WM): Peat dams should be used to block the main canal, with the interval between them determined by a 0.5–0.6 m drop in elevation. Spillways, designed based on the maximum expected rainfall, provide a protective mechanism in the case of extreme precipitation by releasing excess water from the site. With this canal network design, the Ground Water Level (GWL) is tightly controlled, and water is retained long-term due to the retention system; in addition, this system provides a firebreak and ensures tree growth.
The iMRV system is an integrated measuring, reporting, and verifying system, capable of tracking dynamic changes in water- and carbon cycles, biomass and biodiversity, forest degradation (including deforestation), and the impacts of climate change and human interference. However, as tropical zone is always cloudy, it includes a proposal on the informatics based on the iEOS, which uses several different spectral products, 3D photogrammetry, and a GHG sensor aboard the Equator orbiter. The iEOS offers significantly improved abilities to measure variables such as the ground water level (GWL), land subsidence, soil moisture, SOC, carbon flux, CH4 emissions, plant nutrient color-metry (leaf colour), and plant diversity, which contribute to the Tier3 model of CO2/CH4 emission from ecosystem.
Osaki’s team has also developed new methods for mapping CO2 emissions based on the relationships between different satellite-measured variables (Tsuji et al, 2019, Sulaiman et al, 2023). As peatland becomes drained, the oxygen diffused into the peat layer enables decomposition of plant matter, leading to CO2 release. Peatlands commonly emit carbon in the dry season when groundwater levels are low. Therefore, the team uses NASA’s SMAP satellite to generate maps of ground surface moisture (GSM) levels. Osaki’s team also developed a model of GWL-GSM relationship. Using the known relationships between the variables, the estimated groundwater level (GWL) map can be used to estimate the net ecosystem exchange, NEE, a measure of the difference between the CO2 absorbed via photosynthesis and that released via respiration into the atmosphere by living things (plant roots and microbe decomposition) (Fig 5).
Reliable eco-management
The final facet of Peatlogy involves the development of effective NbS to ameliorate E&E degradation and provide sustainability-approaches for land surface management. To counteract the Trilemma model, Osaki’s team advocates for a ‘Triharmony’ approach, whereby three key elements – water (physical element), carbon (chemical element), and nutrients (biological element) – must be balanced to ensure healthy natural systems. Although much of the work until now has focused on tropical peatlands, the Trilemma/Triharmony model can be applied to all ecosystem types. This approach is inspired by the Satoyama Model, a traditional Japanese approach that emphasises the coexistence of agriculture and forest management using organic matter and agroforestry (‘sato’ denotes society and ‘yama’ denotes nature) (Fig 6).
Osaki’s team has developed a new Triharmony approach for large-scale GWL management in tropical peatland. Water, known as the ‘elixir of life’, is critical for the health of all living things, and for the ecosystems in which they live. Climate change, E&E degradation, and human activities have all resulted in disruptions of the natural water cycle. In peatlands, a high water level is critical to ecosystem health, but this is increasingly threatened by slash-and-burn farming, drainage for fields and cultivating of plantation crops, and changes in precipitation by deforestation (reducing latent heat function).
Conventional water management systems in tropical peatland areas are ‘drainage-based’, a system of dams and water channels drain water into a central canal for water removal. However, this ultimately damages the peat structure, resulting in peatland degradation. On the contrary, Mitsuru’s team has shown that the addition of peat dams across the main canal, between contour levels, allows water to stay within the system for longer. This ‘stock-based’ water management approach is similar to traditional approaches used to maintain moisture levels in terraced paddy fields and can stabilise groundwater across the year; prevent damaging peatland by microbe decomposition and fires; encourage the growth of biomass, including trees; and largely conserve the natural ecosystem while also supporting agriculture and silviculture. When evaluated over a 10-year period in West Kalimantan, Indonesia, two large industrial plantations were successfully restored to a healthy state (Kato et al, 2024) (Fig 7).
The team has also expanded on this work by harnessing the lessons learned from plant evolution in waterlogged peatlands, in particular, the development of aerial and mound roots to fix N-nutrients from the air (N2). Their new approach, AeroHydro culture, involves both the maintenance of high groundwater levels using the aforementioned ‘stock-based’ irrigation approaches, and the application of 1) natural composts (piling matter from the local environment such branches or stems) and 2) compost bug (containing compost, microbes, biochar, zeolite, PGP (plant growth promotion) substances, and chicken manure) placed on peatland surface, both of which induce aerial-like roots on land surface and in compost bug. The concept aims to encourage the development of aerial root systems in degraded peatland even in high ground water level areas, allowing them to regenerate. At testing sites in Indonesia, AeroHydro culture successfully resulted in aerial-like lateral root development and an increase in biomass (Turjaman T, et al, 2024) (Fig 8).
Not only is the technology useful for environmental protection, but it can also promote economic development, which is important if it is to see widespread adoption. Oil palm test plots of AeroHydro Culture were found to promote leafing and fruit production. More importantly in terms of ‘selling’ the technology to commercial producers, the oil palm harvesting weight was increased by more than 30%. Similarly, the leafing rate of Shorea balangeran, a native tree species, under AeroHydro culture, was twice that of the control trees after six months.
A number of studies are now considering the role of microbes on plant growth under different peatland conditions, with the potential for microbe use to support AeroHydro culture. Moreover, there is a need to ensure that the materials required for AeroHydro culture, in particular the compost with biochar, zeolite, microbials, is affordable, widely available, practical, and from natural sources.
The next step in Peatlogy is promoting its widespread adoption. Critically, as with any new technology or conceptual approach, stakeholders – from subsistence farmers to governments and multinational corporations – must have the knowledge and willingness to adopt new management styles.
Acknowledgements
The concept of ‘Peatlogy’ is largely generated from projects such as 1) the Japan Society for Promotion of Science (JSPS) Core University Program on ‘Environmental Conservation and Land Use Management of Wetland Ecosystem in Southeast Asia’ between Hokkaido University, Japan, and the Research Center for Biology (LIPI), Indonesia, from Apr 1997 to Mar 2007; 2) the Science and Technology Research Partnership for Sustainable Development (SATREPS) Project on ‘Wildfire and Carbon Management in Peat-Forest in Indonesia’ between Hokkaido University, Japan, and the National Standardization Agency (BSN), Indonesia, founded by the Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA) from Sept 2009 to Mar 2014; 3) the IJ-REDD project founded by JICA in 2014; and 4) the JICA-JPS-BRG Program of the Japan International Cooperation Agency (JICA, Japan), the Japan Peatland Society (JPS, Japan) and the Peatland Restoration Agency (BRG, Indonesia) from Oct 2017 to Mar 2018.
The reports, proceedings and guidebooks of these projects are available from the Japan Peatland Society (JPS) website:
jps.sakura.ne.jp/jspsproc/jspsproc.html
Through the above projects, three books were published on ‘Tropical Peatland’ (Springer), greatly contributing to the ‘Peatlogy’ concept:
1. ‘Tropical Peatland Ecosystems’ (2015) eds by Osaki M, Tsuji N, Nature Springer Singapore Pte Ltd, ISBN-10: 443155680X, ISBN-13: 978-4431556800
2. ‘Tropical Peatland Eco-management’ (2021) eds. by Osaki M, Tsuji N, Foead N, Rieley J, Nature Springer Singapore Pte Ltd, ISBN-10: 9813346531, ISBN-13: 978-9813346536
3. ‘Tropical Peatland Eco-evaluation’ (2024) eds. by Osaki M, Tsuji N, Kato T, Sulaiman A, Nature Springer Singapore Pte Ltd, ISBN-10: 9819967899, I ISBN-13: 978-9819967896.
Personal Response
What is required for Triharmony to be scaled up from the case study-scale to the global scale?A Triharmony system trans-balance among the Ecology-sphere, Environment-sphere, and Resource-sphere worked properly prior to the 18th and 19th century (Industrial Revolution). However, since the industrial revolution, the Trilemma system has been introduced in developed countries, including colonial areas. Eco and environment-system destruction (deforestation and forest degradation, monocropping, plantation) and exploitation of resources is widespread. During the 21st century, Ecology-sphere, Environment-sphere, and Resource-sphere have been retained in the Global South (Global Central among Tropics in our definition). Therefore, a Triharmony system should be reconstructed in Global South (Global Central) by applying NbS (true NbS, not industrial NbS), in which the big TREE model plays a key role because only big TREE regulates and operates the flow and stock of the water-carbon-nutrients (key factors of Nature Asset, which can be regulated by big TREE (forest)), contributing to the amelioration and dispersion of Solar Energy. The Nature Asset in Global Central (Tropics) is still degrading due to high levels of human impact; however, as Nature Assets are still rich and diverse in Global Central (Tropics), the Earth Anomaly should be healed to nature-health by Nature Assets, not by Industrial and economic Assets (or should be minimalised). This NbS-Triharmony system is by far the cheapest and most effective, when cost is calculated with Natural Capital base.