About Ian Lawson

Senior Lecturer at the University of St Andrews

In the pole forests of the Rio Tapiche-Blanco, Peru

As part of our ongoing research on understanding the distribution and dynamics of Peruvian peatlands, I spent part of July with a IIAP-St Andrews-Edinburgh team exploring the floodplain of the Rio Tapiche and its tributary, the Rio Blanco.

Thinly-spaced pole forest near the Rio Blanco

Pole forest near the Rio Blanco

IIAP research boat “Tornillo II” moored in the seasonally flooded forest at the start of a day’s fieldwork.

The Tapiche is a right-bank tributary of the Ucayali, in the south of the Pastaza-Marañón Basin. It’s not exactly remote – our field sites are around eight hours by speedboat from Nauta – but there are only half a dozen small communities between the little service port of Requena and the headwaters of the Blanco, and essentials, especially fuel, are hard to come by. IIAP’s research boat, the Tornillo II, was near its limit with six on board plus food for a week, gasoline and all our sampling equipment.

The logistical pains paid off as we set out to collect field data to test and refine our predictions about the distribution of carbon stored in peat. Gratifyingly, everywhere we thought we would find peat, we did. Our field days involved arriving at a pre-defined point at the river bank, cutting a rough trail through the (usually non-peaty) seasonally-flooded forests bordering the river, then working inland as far as we could within the time constraints of the 12-hour tropical day. Along the way we took samples and recorded the characteristics of the vegetation and soils. This season we are using a combination of the rapid survey techniques we have used in the past, and a more comprehensive inventory that takes a couple of hours for the team to complete (but is still quicker than the four to seven days it takes to set up a permanent census plot).

Sampling peat in the Rio Blanco basin

These techniques are helping us to see nuances in the vegetation that we were not so aware of in the past. Along the Blanco we saw many variations on what the team is now thinking of as ‘jiiri’ – an Urarina word (see our recent publication here) that refers to all ‘open’ peatlands, where ‘open’ can mean anything from totally lacking trees, to a fully closed tree canopy made up of short, thin trees (a ‘varillal’ or ‘pole forest’). It’s becoming clear to us that these environments are very variable, forming a gradient (or several gradients) of varying canopy height, stem density, and canopy openness. There seem to be big differences too in the importance of flooding, and in the character of the substrate (though we have always, so far, found peat underneath them).

Dense pole forest

Pole forest showing clear flood marks

Floristic and geochemical data will hopefully provide a more solid description and functional understanding of these various environments, as will palaeoecological analysis (the chosen topic of PhD student Dael Sassoon). In the medium term, this understanding of how different ecological units inter-relate will help us to understand how and where carbon is stored in the peaty soils of the western Amazon.

We were very generously hosted and assisted in our work by the community of Nueva Esperanza.

CongoPeat PhD – deadline extended

We have extended the deadline for applications for a fully-funded PhD studentship working on the long-term ecology of Congolese peatlands at the University of St Andrews. is 18 January 2019, which fits in with other NERC DTP deadlines. The studentship is available to start on selected dates between May and October 2019. For further details please see the project advert here.

CongoPeat project formally begins

Campsite in a peat swamp forest

Camping in an RoC peat swamp forest in 2012

A new NERC-funded five-year project to study the peatlands of the central Congo basin has been announced. The project, led by Simon Lewis at the University of Leeds/UCL, involves a multidisciplinary team from the UK and the RoC. Dr Ian Lawson of the University of St Andrews is leading Work Package 1, which aims to understand the genesis and history of the Congolese peatland complex.

The project kick-off meeting took place at Leeds on 6-7 September 2018.

The project is creating several new posts, including a PDRA and PhD studentship focusing on the palynology and other palaeoecological aspects of the project. The deadline for applications for the PDRA position has passed but for further information about the studentship, please contact Ian Lawson (itl2@st-andrews.ac.uk) or see the description online. Please note that full funding is only available to UK and some EU citizens – NERC eligibility requirements are here.

More information about this exciting project is available at the project website.

Setting up intensive measurement plots in Peru

From April to July 2018 Greta Dargie, Jhon del Aguila Pasquel, Julio Iriarica and Ian Lawson have been busy in the swamp forests of the Pastaza-Marañón Basin setting up monitoring sites.

At two key sites, at Nueva York and Veinte de Enero, we have installed a suite of equipment and initiated measurements aimed at measuring litter production and decomposition rates. At 14 further sites we are installing automated dipwells and litter decomposition bags. The aim is to better understand why carbon-rich peat soils accumulate in some places and not others.

A basal peat core from an open peatland at Veinte de Enero

Commuting to work through the flooded forest at Nueva York

Measuring the height of a palm tree

Setting up a litter transect

Installing a rain gauge at Veinte de Enero

One of the inhabitants of the aguajale: a skink

Coding

Christopher, Nina, Katy and Ian spent an interesting few hours surrounded by post-it notes, thinking through how to ‘code’ (analyse) the 51 interview transcripts, amounting to something like 150,000 words, generated by our SFC-ODA project on valuing peatlands in Amazonian Peru.

Interdisciplinary research in action!

Many interesting themes emerged – not least the myths, legends and superstitions that surround wetland environments in Peru – just as they do in the UK. We are also interested in themes such as resource use, sustainability, and gender issues.

Now that the decision has been taken about what to look for in the transcripts, the hard work of analysis will begin…

New paper: Continuous human presence without extensive reductions in forest cover over the past 2500 years

A new paper by Tom Kelly and other members of the Tropical Wetlands Consortium has just appeared in Journal of Quaternary Science.

Dr Tom Kelly and IIAP research assistant Julio Iriarica coring on Quistococha

As part of his PhD work, Tom showed that the lake at Quistococha, on the outskirts of Iquitos in Peru, contains a remarkable pollen and microcharcoal record. The data show an increase in pollen of the disturbance indicator Cecropia over the past century and a half, presumably reflecting the growth of Iquitos. Prior to that, the pollen record suggests little change in forest cover, despite a continuous microcharcoal record suggesting the presence of human populations.

A critical piece of evidence supporting our interpretation of the microcharcoal as an indicator of human presence was provided by co-author and archaeologist Santiago Rivas Panduro, who had previously published the results of excavations at an archaeological site adjacent to the lake. There, pottery, plant remains, and radiocarbon dates provide unequivocal evidence for prehistoric human occupation.

We suggest that the new record helps to support an emerging understanding that, in the wettest parts of Amazonia, there may have been little deforestation before modern times. This is an important qualification to the growing body of evidence from more seasonally-dry parts of the Amazon Basin which suggest that there, much of the forest had been cleared, at least episodically, in pre-Columbian times.

The article is published here.

Talks and TV appearances in Iquitos

Thumbs up all round following a successful TV interview

Poring over a map, planning our fieldwork campaign

During a project planning meeting in Iquitos Tim Baker, Ian Lawson, Santiago Rivas Perez and Euridice Honorio Coronado took the opportunity to present our recent work on Quistococha (Kelly et al. 2018) at the Ministry of Culture in Iquitos. We also appeared twice on local TV – a fun experience!

New paper on Amazonian peatland forests

Freddie Draper and colleagues have a new paper in Ecography, online as an accepted article.

The paper, Peatland forests are the least diverse tree communities documented in Amazonia, but contribute to high regional beta-diversity, uses floristic data from a network of plots to show that peatland palm swamps and pole forests host distinctive floras.

Although, at the plot level, peatland forests are typically much less diverse than dry-land forests, the paper argues that they make a substantial contribution to regional beta diversity which, together with their dense below-ground carbon storage, enhances the case for conserving them.

This paper grew out of data and analyses conducted by Freddie during his NERC-funded PhD.

NERC project “Carbon Storage in Amazonian Peatlands: Distribution and Dynamics” begins

Our new NERC-funded project officially begins today, with the appointment of Dr Greta Dargie as a PDRA at St Andrews. Greta will be leading field and lab data collection, initially working with colleagues at IIAP in Iquitos.

Greta has been in the news recently in relation to her pioneering work in mapping Congolese peatlands: http://www.theguardian.com/environment/2017/nov/12/congo-basin-swamps-peatlands-carbon-climate-change.