Climate Change and Maize Farming in Belize – Reflections on my PhD field work

PhD Raquel Chun shares reflection from her field work:

“Now in 2021, data collection is starting up again but with extra careful planning and adhering to strict protocols to ensure both myself and my farmers are safe. I have been out in 5 farms already doing soil collecting and conducting 4 interviews. My farmers are happy to see me again but they are also very concerned about Covid-19. All of our lives are different from the last time we spoke in 2019.

Reminiscence

As I progress- albeit a bit slowly – on data analysis, the memories of my adventures during fieldwork come back with surprising clarity. In 2019, I trudged barefoot across a river, tripped over farm debri, drove – slipping and sliding in my 2-wheel drive, sturdy little SUV- over muddy roads and partook in simple, local meals over a period of 6 months in southern Belize.

First of all, my project under the Global Challenges Research Fund Centre for Doctoral Training at Durham University and co-supervised by Dr Lisa Baldini at Teesside University is to research the impact of climate change in the decision making of indigenous Maya farmers in three villages in southern Belize. This involves monitoring changes in weather and climate utilizing weather station and historical data, conducting ethnographic interviews with Maya farmers as well as soil monitoring and crop yield measurements. My research seeks to offset the lack of information on the impact of climate change on smallholder farmers by studying the impact of changing weather patterns on the decision making of Belizean Maya farmers in the Toledo District over the long and short term.

My first year of data collection in 2019 started with a metaphorical bang. Initially, I was arranging meetings with the local leaders of three Maya communities as per cultural protocol in order to introduce the project and find farmers who were willing to participate. The community leaders of the first community I approached were very eager for their farmers to participate in my study so I was off like a shot, arranging meetings with interested farmers and planning farm visits to start soil sampling with the knowledge I had gathered since I had begun my studies in February 2019.  The data collection was a challenging yet fulfilling journey that yielded new friendships and knowledge.  

As I started this journey, I was unaware of how much it would truly impact my life and help me learn more about the lives of smallholder Maya farmers. Although I am an indigenous Maya woman, I grew up in a more urban setting, 3 miles from the capital city of Belmopan. Therefore, as I went along my fieldwork visits, I learnt about local beliefs surrounding farming as well as the struggles these families go through as they make their living. It made me gain more perspective on the issue of climate change and how it affects the livelihoods of the most vulnerable people. I have been welcomed with open arms and a lot of curiosity due to the fact that I am a Mopan Maya female studying for a PhD in the field of agriculture and climate change which is mostly foreign to them as well. This dynamic has made for some interesting conversations with farmers’ and their families.

At the end of 2019, I had two data collection rounds doing soil sampling of farms, conducting interviews with farmers and taking crop yield measurements after harvest.

COVID19 Pandemic – impact on my work

Well we all know what happened in 2020 with a global pandemic almost bringing the world to a standstill. This, of course, included my fieldwork which was both a blessing and a curse. In April of 2020, I became the mom of a bright-eyed, curious baby boy. Motherhood itself has been a whole other journey. Due to the COVID 19 pandemic, there was no soil sampling. There was no conversations with farmers especially with Covid19 cases rising steadily in the country. The entire world had changed and we needed to figure out how to live in it. Luckily, I was able to return to my country before the pandemic caused lockdowns and before my baby was born.   ” 

Unique signatures

One of the most amazing things I love about research is that you are constantly learning, constantly exploring and driving forward understanding. I am so pleased to share a recent publication entitled Unique chemical parameters and microbial activity lead to increased archaeological preservation at the Roman frontier site of Vindolanda UK.

The paper is open access and free to read, from scientific reports and here are five reasons why you should:-

  1. Microbes are fascinating and we understand so little about how they impact on preservation on artefacts
  2. Inorganic analysis – such as metals, play a huge part in the activity of microbes and thus preservation
  3. The diversity of microbes change depending on archaeological context.. and guess what this will impact on preservation
  4. The graphs are really cool
  5. It shows we need to understand the chemical and microbiological environment to understand our management practices for the future..

Sampling the soil

New Output: Unique chemical parameters and microbial activity lead to increased archaeological preservation

Orr, C.H., Williams, R., Halldórsdóttir, H.H. et al. Unique chemical parameters and microbial activity lead to increased archaeological preservation at the Roman frontier site of Vindolanda, UK. Sci Rep 11, 15837 (2021). https://doi.org/10.1038/s41598-021-94853-7

Published: 04 August 2021

Abstract: Waterlogged burial conditions impact upon artefact preservation. One major determinant of preservation is presence and behaviour of microorganisms, however, unravelling the mechanisms, especially in waterlogged conditions is challenging. In this study, we analysed elemental composition, bacterial diversity and community structure from excavation trenches at the Roman Site of Vindolanda, Northumberland, UK, using pXRF and 16S rRNA gene amplicon sequencing. Excavation trenches provide information of different occupation periods. The results indicated that microbial communities were dominated by Firmicutes, Bacteroidetes and Proteobacteria at a phylum level. Samples which also had visible vivianite presence showed that there were marked increases in Methylophilus. Methylophilus might be associated with favourable preservation in these anaerobic conditions. More research is needed to clearly link the presence of Methylophilus with vivianite production. The study emphasises the need for further integration of chemical and microbiome approaches, especially in good preservation areas, to explore microbial and chemical degradation mechanisms.

New paper: Heterogeneity enables coexistence of native and invasive aquatic plants

Salgado, J., Sayer, C. D., Willby, N., Baker, A. G., Goldsmith, B., McGowan, S., Davidson, T. A., Bexell, P., Patmore, I. R. & Okamura, B. (2021) Habitat heterogeneity enables spatial and temporal coexistence of native and invasive macrophytes in shallow lake landscapes. River Research and Applications. https://doi.org/10.1002/rra.3839

First published: 15 July 2021
Abstract:
Macrophyte invasive alien species (IAS) fitness is often hypothesised to be associated with beneficial environmental conditions (environmental matching) or species-poor communities. However, positive correlations between macrophyte IAS abundance and native plant richness can also arise, due to habitat heterogeneity (defined here as variation in abiotic and native biotic conditions over space and time). We analysed survey and palaeoecological data for macrophytes in satellite lakes along the Upper Lough Erne (ULE) system (Northern Ireland, UK), covering a gradient of eutrophication and connectivity to partition how environmental conditions, macrophyte diversity and habitat heterogeneity explained the abundance of Elodea canadensis, a widely distributed non-native macrophyte in Europe. E. canadensis abundance positively correlated with macrophyte richness at both the within- and between-lake scales indicating coexistence of native and invasive species over time. E. canadensis was also more prolific in highly connected and macrophyte-rich lakes, but sparser in the more eutrophic-isolated ones. Partial boosted regression trees revealed that in eutrophic-isolated lakes, E. canadensis abundances correlated with water clarity (negatively), plant diversity (positively), and plant cover (negatively) whereas in diverse-connected lakes, beta diversity (both positively and negatively) related to most greatly E. canadensis abundance. Dense macrophyte cover and unfavourable environmental conditions thus appear to confer invasibility resistance and sufficient habitat heterogeneity to mask any single effect of native biodiversity or environmental matching in controlling E. canadensis abundance. Therefore, in shallow lake landscapes, habitat heterogeneity variously enables the coexistence of native macrophytes and E. canadensis, reducing the often-described homogenisation effects of invasive macrophytes.

Lecturer in Environmental Science (2 Posts)

Our Department is advertising for two permanent positions of lecturer in environmental science. The newly appointed lecturers have an opportunity to take a leading role in our Earth, Ecology and Environment research collective and bring their own research and/or consultancy expertise.

The job ad can be found following the two links below:

Job.ac.uk

Teesside HR

If you would like to discuss how your research could fit within the Earth, Ecology and Environment research collective – please get in touch with Ambroise a.baker@tees.ac.uk.

Slogging for Skelton

Just this week, our new paper on “Mapping an archaeological site: Interpreting portable X-ray fluorescence (pXRF) soil analysis at Boroughgate, Skelton, UK” was published! And so, we thought it would be nice to share some of the work that went toward this with you all.

Boroughgate was a 12th Century medieval borough in Skelton, North Yorkshire UK, near the All Saint’s Old Church and Skelton Castle. It was placed in the perfect location to support trade and income for the castle via but unfortunately it was unsuccessful and abandoned around 1400 CE. The remnants of earthworks at the site and medieval documentation recording some of the tradespersons at Boroughgate gave some clues as to the history of the site. Tees Archaeology went through a series of surveys before excavating the site, inviting us out to complete some pXRF analysis and explore whether pXRF elemental analysis can enhance and support their interpretations of the site. This was also an excellent opportunity for us to show the value of our method development for pXRF soil analysis in archaeology! Admittedly, this also may have been a bit of an excuse to get out on such a glorious Summers day…

Better get the sun lotion on because it’s a scorcher at Boroughgate!

pXRF is often seen as a rapid point-and-shoot method  but for good quality data, we really need an appropriate methodology. The soil matrix can vary greatly over just short distances, and we need to make sure that all our soil is examined in the same way, otherwise our comparisons are inconsistent and not well validated. We extract soil samples, dry them in the lab (preferably oven dried), grind down and sieve the samples so they’re nice and homogenous, and prepare them into pXRF sample cups. This does of course mean that we end up with a fair bit of soil samples in the lab from just one small area of soil..!

Nice selection of sorts sorted for scanning back at the lab

Research into social organisation and the activities or use of space from archaeological excavations uncover hidden knowledge on past societal practices and the structuring of historic communities. This work explored whether we could map out the elemental distribution of soil to identify different activity areas. This is discussed in much more detail in the journal article but just briefly, the distribution of aluminium, phosphorus, potassium calcium and iron distinguished between the internal dwelling and external area of a longhouse. Aluminium, potassium and calcium also distinguished a likely clean or food preparation area against a refuse area. These areas also aligned closely with the locations of artefacts such as pottery fragments, daub, and domestic or charred waste, as well as structural remains such as building foundation pads, postholes and wall foundations.

Summary of the pXRF interpretation. More pictures and diagrams in the paper!

This was a well worthwhile investigation into mapping pXRF of soil which we’re very excited to continue further. Don’t hesitate to contact us if you’re interested in surveying your site with pXRF, we’d love to see how much more we can learn about past communities with pXRF! Now before you go, don’t forget to say hi to the ridiculously sweet kitten which I’ve dubbed Sandy the Archaeology Cat because of its love for sitting in soil buckets and climbing over your shoulders judging your use of the Harris Matrix:

Sandy is the sweetest!

And finally, thanks to David Errickson at Cranfield University, and Tees Archaeology for inviting us out to your site!

TUBA

Research grant to study geochemical and microbial conditions underpinning turf preservation at the Roman site of Vindolanda, UK

Drs G Taylor and C Orr won a new grant to carry out the work as follows.

The Roman Fort site at Vindolanda is known for the exceptional preservation of its finds, among them wooden writing tablets and leather shoes. A recent study into Roman construction practices at the site demonstrated that this preservation extends to the turf ramparts, with plant fibres and seed heads still visible and microbes seemingly surviving within the soils. While that earlier project focused on turf in building, this new one will evaluate what this same material can reveal about the ancient environment. As a pilot study, it will assess the geochemical and microbial conditions, which underpin this preservation, and evaluate the turf blocks’ potential as environmental archives to reconstruct the landscape around the fort through time. Results will inform four smaller-scale follow-on analytical packages and three large-scale interdisciplinary funding applications to investigate the economic and ecological impacts of turf sourcing and turf’s potential as a zero-carbon building material for the future

Sustainable Drainage Research at Climate Exp0

Dr Ed Rollason, along with colleagues at Durham University and University College Dublin are collaborating on a project exploring how we conceptualise Sustainable Drainage Systems (SuDS) as mechanisms for enhancing high density urban environments. They are currently exhibiting a poster on the work at Climate Exp0, a free conference being run as a prequel to the COP26 climate summit to be held later in the year.

Sustainable drainage systems are key components of urban drainage infrastructure for new build houses. However, retrofit takeup of SuDS is low and generally unimaginative, and projects often do not meet their aspirations for delivering multiple benefits. We argue that identifying the effectiveness and potential for retrofitting SuDS requires understanding the nexus between the nature of the problem being addressed, the place in which the intervention is being implemented, and the level of investment which is being made available. This paper will propose a new conceptual model integrating these factors which will allow SuDS designers and promoters to better understand where and how to implement SuDS to achieve the greatest chances of success and the greatest co-benefits.

pXRF on pathology! Catching up with a student publication

Recently, we worked with Naomi Kilburn, a Master’s student at Durham University, whose dissertation project titled ‘Assessing pathological conditions in archaeological bone using portable X-ray fluorescence (pXRF)’ was published just this month! Fab, right? We took a moment from our calendar of Teams calls to have a Zoom call with Naomi and catch up on her work, experience, and the research.

Naomi Kilburn, the newly published researcher!

Hi Naomi! So first off, tell us about yourself – what’s your research passion?

My passion is for palaeopathology – I love looking at human skeletons to see what they can tell us about health, diseases, and life in the past.

Oh wow, fascinating! What area of palaepathology do you enjoy the most?

There are so many fascinating areas to explore, but… at the top are studying infant and childhood health and looking for ways to expand how we learn about health in the past.

What pathway did you take to get into palaeopathology?

I recently completed my master’s at Durham University and I’m currently working on securing some PhD funding so that I can keep asking (and maybe sometimes even answering) exciting questions about people and their bones.

So your paper, Assessing Pathological Conditions in Archaeological Bone using pXRF… how did that get started?

Well, this project came about through talking with Becky Gowland, my advisor at Durham, about possible dissertation projects.

Becky suggested portable X-ray fluorescence (generally called pXRF, as otherwise it’s quite a mouthful) as a way to combine studying children with a new palaeopathological technique.

My major research question was thus formed: Can pXRF be used to distinguish between different diseases in archaeological bone?

Mmm yes I can see how that idea was formed! Were you ready and raring to go or did you have a couple more hurdles to jump?

Ah yes, so, with the project idea settled, I then needed to figure out how to access a pXRF. Luckily, Becky knows many people and put me in contact with Tim Thompson at Teesside University.

After getting the go-ahead from Tim, I carefully packed some femora into boxes and headed to Teesside.

pXRF set up and ready to go.. safety first!

Excellent! How did you find coming to Teesside for a few days?

Rhys and Helga rolled out the welcome mat, showed me around the campus and gave me a crash course in using pXRF. And bingo, I was all set!.. until some unexpected hiccups…

Oh no! What happened?

The pXRF stopped working properly and had to be repaired, which muddles up all the project timelines. Disaster! (Okay, so it wasn’t that much of a disaster). But, with Helga’s supreme organisation and flexibility of everyone using the pXRF, things were quickly back on track better than ever!

Glad to hear it was sorted out! So… what did the pXRF do?

With pXRF, I could zap the bones with X-Rays and find out what kinds of elements are in the bones (and how much of them there is!).

What did this tell you?

I found that the real time-consuming part of pXRF was playing with all the numbers and figuring out what they might mean. My summer was spent making scatterplots and doing statistical tests to try and tease out patterns in the data that could be related to scurvy, or rickets, or any of the other diseases I was looking at.

Data, data, data! What did you find out?

The patterns remained elusive (science!), but the search was fun! I looked at elemental ratios potentially related to cribra orbitalia, neoplastic disease, rickets, scurvy, syphilis, and pathological new bone formation. Unfortunately, elemental ratios were more closely related to post-burial processes, but examining larger sample sizes of each pathology could shed light on new information.

I see! Did you find out anything else?

Actually, I found out how useful the pXRF is! This work couldn’t have been done without pXRF because it allows rapid and non-destructive analysis (can’t go chopping up and grinding down archaeological collections willy-nilly!).

Awesome, go Team pXRF!

 

It’s absolutely fantastic to see students get their work get published, it’s such a great boon for PhD application process. I’m sure you’ll join us in wishing Naomi all the best in her bright academic future, we look forward to seeing what comes next!

TUBA