March 03, 2025
Peatlands store and sequester more carbon than any other type of terrestrial ecosystem. These unique ecosystems can be found on every continent and cover 4.23 million km2, equal to 2.84% of the land on our planet. They offer a range of benefits to climate, communities and biodiversity.
These terrestrial wetlands are characterized by waterlogged conditions, which prevent plant material from fully decomposing. Because organic matter accumulates faster than the rate of decomposition, the result is peat, a concentrated substance that’s especially rich in carbon. Critical to the health of these ecosystems is water.
But what exactly is peat water, and how does it differ from freshwater? In this article, we’ll dive into the many unique characteristics of peat water, to explore its composition, coloration, and its importance to peatland ecosystems around the world.
1. It has a unique composition
The peat water found in landscapes such as Restorasi Ekosistem Riau (RER) is especially rich in organic matter from decaying plants. Look a little closer at this life-giving resource and you’ll discover peat water has some special characteristics that set it apart from freshwater.
Tests on peat water have revealed a high degree of acidity (pH levels between 3-5), high suspended sediment concentration, and high concentrations of Fe metal and organic carbon, also referred to as Dissolved Organic Carbon, or DOC. High pH means less mineral available for plants, notably phosphorus, which generally makes peat soil less fertile.
2. Not everyone’s cup of tea
Peat water is typically dark brown or tea-colored, due to high levels of tannins and humic acids released by decomposing vegetation. The red-brown coloration of peat water is usually caused by the presence of humic and fulvic acids, including Fe and Mn minerals.
The rich cocktail of organic compounds in peat water comes from the soil, because peatlands are inundated throughout the year. Rather like tea leaves left over time to stew in a pot, this creates an extremely strong brew of organic compounds.
3. It’s not safe to drink
This high concentration of compounds, along with halogen ions and high acidic content, which can be harmful to dental health in the long term, means that peat water is generally unsafe for consumption. Untreated peat water can cause a wide range of health issues, so special filtration treatment and boiling is needed before it can be used as drinking water.
In many rural regions of Southeast Asia, peat water and rainwater are the only options available to isolated communities. Various studies are currently underway, trying to find sustainable solutions to water shortages in these areas.
4. Rain water causes peat soils to shrink and swell
Most organic soils shrink when dried but swell when re-wetted, unless they are dried to a threshold value beyond which irreversible drying occurs. Shrinkage calculated as a percentage of the original volume ranges from 90% for aquatic peats to 40% for fibric peats.
This is especially true for lowland coastal peat regions in Indonesia, where organic soils appear to become less affected by drying after they have been cultivated for some time. Here, the wood content of the peat influences shrinkage, as it provides a stable skeleton which prevents the soils from shrinking.
5. Wetter is Always Better
When peatlands dry out, they become a potentially dangerous tinder box. To prevent fires, it is essential to keep them moist through natural inundation with peat water. The organic materials in peat swamps dry out easily when exposed to the sun, and the materials become like coffee grounds, making them very difficult to re-wet.
The reabsorption of water is made more difficult by the hydrophobic nature of dried peat. Acidic, humified peats have shown the greatest resistance to re-wetting because of their high lignin content, along with the presence of carboxyl and phenolic hydroxyl groups.
Resistance to re-wetting also appears to be related to bulk density. Irreversible drying is marked in organic soils with low bulk density, whereas those with high bulk densities are comparatively easy to re-wet. Peatland soils reaching the stage of irreversible drying show a marked loss of water holding capacity, which can be as much as 40-75%.
6. When Addressing Climate Change, Peat Water Offers a Solution
Peat water is essential for supporting the rich biodiversity found within peatland ecosystems. Keeping these areas wet, wild, and healthy also has a direct bearing on global climate change mitigation.
In their natural, wet state, peatlands have the potential to provide essential Nature-Based Solutions (NBS) that can help mitigate the effects of climate change. They regulate water flows, reduce the risk of flooding and droughts, and help prevent seawater intrusion.
Wet peatlands have been proven to lower temperatures in surrounding areas, providing respite from extreme heat, and even improving air quality. As global temperatures continue to rise, so too does the importance of preserving these valuable carbon sinks.
In many parts of the world, peatlands supply food, fiber, and other local products that sustain economies.
Peatlands in RER
Whether supporting biodiversity, regulating water cycles or mitigating climate impacts, peat water is an essential feature of healthy landscapes. At RER, we are working to protect and restore these areas through constant study, research and regeneration projects. So long as peat water continues to flow through the peatlands of Riau, hope for the future of our planet will continue to spring eternal.
