Tropical peat swamps: Restoration of endangered carbon reservoirs

Last week, a very interesting paper was published that uses palaeoecological techniques to provide insights into the recovery dynamics of tropical peat swamp forests in Indonesia, with the aim of informing their contemporary management. The official Press Release for the publication is re-posted below (from the Journal of Ecology blog) with the kind permission of the first author, Kartika Anggi Hapsari. 

University of Göttingen press release

According to current knowledge, the land biosphere absorbs 30% of the CO2 produced by humans and thus contributes significantly to reducing global warming.

Tropical peat swamp forests are among the most important terrestrial carbon reservoirs, but they are increasingly being cleared. Data on their regenerative capacity have so far been completely lacking but are indispensable for conservation and restoration projects.

A research team of the Collaborative Research Centre (CRC) 990 of the University of Göttingen has now determined for the first time by means of palaeoecological investigations how long it takes for a tropical peat forest to recover after a disturbance. The Leibniz Centre for Tropical Marine Research (ZMT) in Bremen was also involved in the study, which was published this week in Journal of Ecology.

A peat swamp forest in Sumatra which has been converted into a palm oil plantation (Tim Rixen, Leibniz Centre for Tropical Marine Research)

A peat swamp forest in Sumatra which has been converted into a palm oil plantation (Tim Rixen, Leibniz Centre for Tropical Marine Research)

Using one such drill core, which contains deposits from the past 13,000 years, the researchers investigated traces of charcoal as an indication of human habitation, the composition of pollen and spores as well as the carbon content in various soil layers, which they dated with the radiocarbon method.

The drill core originated from a swamp area on the Indonesian island of Sumatra, where the Malayu Empire reigned from the 9th to the 14th century. The nearby Buddhist temple complex Muara Jambi from this period is one of the largest in Southeast Asia and indicates a flourishing high culture.

As the peat samples and historical sources showed, the population then used the swamp forests for the extraction of firewood and building materials and also collected food there. In the 14th century Javanese immigrants displaced the Malayu from the region; the swamp forest was left to itself again.

“It was a rather low-impact use that largely preserved the hydrologic soil conditions,” said biologist Kartika Anggi Hapsari, first author of the study. “Yet we found that it took 60 years before similar amounts of carbon were sequestered in the peat deposits and even 170 years before the original vegetation as found in a virgin peat forest was restored.“

The Indonesian government has recognised the enormous importance of peat forests, not only as CO2 sinks but also as biological treasure troves with a high biodiversity and a number of endangered species, such as the orangutan. Restoration projects in Indonesia, however, are only designed for 60 or for a maximum of 95 years. According to the findings of the study, this period is far too short to restore the full ecosystem performance of an intact peat swamp forest.

“Given today’s practice of extensive deforestation and intensive use as plantations, it is likely that the regeneration will take much longer,” said Tim Jennerjahn of the ZMT, one of the authors of the study. “The question is also how long these peatlands will continue to exist. Due to the drainage and the decomposition of the organic peat soil, CO2 is released, leading to soil subsidence. The peatlands, most of which are located near the coast, could fall victim to rising sea levels.”

The research was conducted within the Collaborative Research Centre 990 “Ecological and Socioeconomic Functions of Tropical Lowland Rainforest Transformation Systems (Sumatra, Indonesia) – EfforTS”, which is funded by the German Research Organization (DFG).

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Read the full article (freely available for a limited time): 
Hapsari KA, Biagioni S, Jennerjahn TC, et al. Resilience of a peatland in Central Sumatra, Indonesia to past anthropogenic disturbance: improving conservation and restoration designs using palaeoecology. J Ecol. 2018. DOI: 10.1111/1365-2745.13000

Media contact:
Kartika Anggi Hapsari, University of Göttingen, Email: kartika.hapsari@biologie.uni-goettingen.de, Tel: +49 (0)551 39 7873

Protecting Peru’s peatlands

In an article published this month in the journal Conservation Biology members of the UKTPWG and colleagues identify and map threats to the recently-described intact peatlands of the Pastaza-Marañón Foreland Basin in north-east Peru. They highlight the need to protect these peatlands to avoid future degradation, and identify several key pathways for conservation.

The Mauritia flexuosa palm at the site of Quistococha

The authors found that, in their case study area, the main threat to peatland health is the expansion of commercial agriculture linked to the development of new transport infrastructure, which makes it easier for companies to access remote areas.

Although some of the peatlands in the PMFB were found to fall within existing legally protected areas such as national parks, this protection is patchy, often weak, and not focused on protecting the most carbon-rich areas.

The article argues that conservation efforts should be focused in the first instance on the most carbon-rich peatlands, such as those north of the Marañón which currently lie entirely outside of the legally protected areas.

The paper’s authors are based in the School of Geography and Sustainable Development at the University of St Andrews (Roucoux, Lawson), the University of Leeds (Baker), University of Edinburgh (Mitchard), University of Reading (Kelly), Instituto de Investigacion de la Amazonía Peruana (del Castillo Torres, Honorio Coronado), Carnegie Institution for Science, Washington DC (Draper), Arizona State University (Lahteenoja), George Mason University (Gilmore), and the Field Museum, Chicago (Vriesendorp).

Link to the accepted manuscript: http://onlinelibrary.wiley.com/doi/10.1111/cobi.12925/full

The new TOC-loss-ometer!

This week, Sarah Cook, a member of the UK TPWG and PhD student at the University of Leicester, published an exciting paper documenting a new, low cost and easy-to-use methodology for measuring DOC losses from tropical peatlands.  Here she describes this important work.

My research is focused on investigating fluvial organic carbon (TOC) losses from tropical peatland oil palm plantations, within Southeast Asia. However, when I first started developing my research methodology I found limited guidance for analysing tropical TOC water samples. Tropical work is often undertaken in remote field sites with limited on-site laboratory facilities (if any), with any flat stable surface (i.e. the dinner table, car boot and concrete floors) quickly becoming a state of the art workbench. In addition, temperature also plays a significant role, with the hot sticky heat quickly degrading anything remotely organic. In my case this could mean the breakdown, and loss, of significant proportions of organic carbon from my water samples. This also meant the need to ship large, heavy and expensive boxes of samples back to the UK for analysis on specialised analytical equipment.

Collection of fluvial organic carbon from an oil palm plantation drainage channel.

This prompted us to develop better guidance for tropical researchers for TOC analysis, and lead to the publication of a water storage paper (https://doi.org/10.19189/MaP.2016.OMB.249) in 2016 and a recent paper in Water Research (February, 2017; http://dx.doi.org/10.1016/j.watres.2017.02.059). In this most recent paper we investigated the suitability of UV-visible spectrometry to determine dissolved organic carbon (DOC) concentrations in tropical water samples, building on an original methodology developed by (Carter et al.2012; http://dx.doi.org/10.1016/j.watres.2012.05.021) on temperate peat. Overall UV-visible spectroscopy (using both a single and two-wavelength approach) was able to accurately predict tropical DOC concentrations. This offers research groups working in remote field locations the ability to rapidly analyse water samples post-collection, negating the need to store degradable samples for lengthy periods of time, helping improve spatial and temporal DOC measurements. In addition, the equipment required for this analysis can be set up at a field base, valuable for researchers in remote locations with limited access to specialised (and often expensive) analytical equipment. This in turn can help reduce the number of samples that need to be shipped back, further helping to reduce research costs. Full details of both papers can be found at:

https://doi.org/10.19189/MaP.2016.OMB.249

http://dx.doi.org/10.1016/j.watres.2017.02.059

Graphical abstract from the Water Research paper, showing an example of a plantation drainage channel and predictive ability of the UV model.

New report from the EIA

The Environmental Investigation Agency (EIA) has recently published a report, Deforestion by Definition, that describes some of the primary causes of deforestation in Peru, and the complexities of the issue.  Some of the areas where deforestation is rampant are close to the peatlands where members of the UK TPWG are doing important research: trying to highlight their location and document their ecological, economic and societal value before the loggers and diggers reach them.