TREMOR: Mechanisms and consequences of increasing TREe MORtality in Amazonian rainforests

Lead Research Organisation: University of Leeds
Department Name: Sch of Geography

Abstract

Mortality rates of trees in Amazonian rainforests have been increasing for at least 20 years. Yet, there have been no real attempts to understand the mechanistic basis of this result. TREMOR will use a combination of forest inventory data analysis and process-based modelling to investigate several hypotheses that could explain the increases in mortality. These hypotheses include (i) increasing wind disturbance, (ii) increasing drought frequency, (iii) increasing liana abundance, (iv) increased competition and (v) faster senescence. Finally, we hope to scale-up the impacts of increasing tree mortality on Amazon-wide carbon storage by using a dynamic global vegetation model.

Planned Impact

We expect our work to have impact locally and more widely.

Local Impacts

1. Strengthening of local institutions.

We believe that it is important for local institutions and communities to be fully engaged with the work we do. Our measurement sites will be spread across different parts of South America. The project will create direct opportunities to strengthen local research institutions. The field data generated by the project has the potential to generate several spin-off MSc and PhD projects that local students could undertake and we will seek to actively develop these possibilities.

2. Policymakers in South American countries.

Our team already has strong links with policymakers in South America. We seek to develop this further by holding one-day workshops with community leaders, conservation leaders, members of local government and other stakeholders to discuss our work.

Wider impacts

3. The general UK (and wider) public. The work done by members of our team has generated plenty of media interest in recent years. We are firmly committed to disseminating the results obtained by this Project to the wider public, as we have done with our previous research. To improve our ability to communicate our research to the general public, the PI will attend media training course at the Royal Society. The ForestPlots.net and RAINFOR websites currently provide a portal of engagement with the wider public, both in Latin America and the UK. The interface of both websites is already trilingual (English, Spanish, Portuguese) and we have trilingual social media (Facebook, Twitter). In TREMOR, we aim to enhance our public & policy engagement by developing interactivity. More specifically, we aim to develop a new graphical interface to demonstrate results in maps and allow users to interactively create visualisations of (a) tree mortality trends and (b) key modelling results showing projected future trends, their sensitivity to climate-change, and consequences for carbon storage.

4. . Research-based teaching

We are firm believers in communicating the excitement of our research to university and high school students in the UK. The University of Leeds already has a culture of research-based teaching and the work proposed in this project will be incorporated in appropriate lecture material for Level-2 and Level-3 courses on Ecosystem Processes and Amazonian rainforests, respectively. University Open Days regularly feature the work of our team and we will prepare and Open Day 'taster' sessions on the topic of increasing tree mortality in Amazonian rainforests. The Geography Department at the University of Leeds also has a regular outreach programme to local schools and teachers. Recent examples of this include a visit to Notre Dame High School, located close to the University of Leeds campus as part of a careers event for final year students and a presentation made to a group of local school teachers on advances in geography. We hope to make the most of these existing opportunities to communicate our science to high school students and teachers and allow them to ask us questions on our work. This outreach will be done at no extra cost to NERC.
 
Description TREMOR has achieved several key 'firsts', which are currently either in review or under an advanced stage of preparation : 1) the first analysis of predictors of tree-death across the entire Amazon, 2) the first pan-Amazon evaluation of plant hydraulic properties associated with resistance to drought, 3) the first large-scale assessment of non-structural carbohydrate concentrations across Amazonia and 4) the first evaluation of how tree mortality trends differ across different Amazon regions.

Significant project manuscripts include a publication in Nature Communications in 2020 on the underlying causes of tree death across Amazonia forests, using data from over 120,000 trees (https://www.nature.com/articles/s41467-020-18996-3). The study received wide attention from a broad range of national and international media (e.g. https://www.dw.com/pt-br/árvores-amazônicas-estão-vivendo-menos-diz-estudo/a-55585568) and unravelled the importance of a large number of individual and species-level predictors on the tree mortality of Amazonian trees. Another significant project manuscript, accepted in Nature Communications, highlights the important role of non-structural carbohydrates in modulating seasonal response to drought in Amazonian forests. Our study on variation in hydraulic traits across Amazonia is now under review in Nature.
Exploitation Route The project provides substantial new insights into how trees die and why tree mortality has been increasing across Amazonia. The new datasets generated allow us to understand how sensitivity to drought varies across Amazon forests over large spatial scales and helps to constrain vegetation model predictions of the climate change impacts on Amazon forests.
Sectors Agriculture

Food and Drink

Environment
URL https://www.yourweather.co.uk/news/science/scientists-reveal-why-tropical-trees-die-in-csi-amazon.html
 
Description TREMOR has played an important part in training a new generation of scientists, providing them with important expertise that will allow them to gain insights into the sensitivity of tropical ecosystems to drought. All project field campaigns thus far have involved local undergraduate and master's level students. In total, ~20 students from three different South American countries (Brazil, Bolivia, Peru) have participated in project field campaigns. Some of these have gone on to use skills acquired through the project in their dissertations and have gone on to train other students as well. The data collected by the project has also directly been used by two Brazilian PhD students (one based at Leeds and one based at UNICAMP in Sao Paulo) and three MSc students in Acre. Additional workshops have been held in all three partner countries, raising awareness of the potential impacts of climate change on local ecosystems and providing a wide array of local students with opportunities to learn how to make measurements of plant hydraulic traits. The results of the project have also provided new insights into how tree mortality risk varies across Amazonian forests. Key outputs include: 1) basin-wide analysis of mortality risk factors, 2) the first pan-Amazon dataset of hydraulic attributes of dominant Amazonian tree taxa, 3) the first pan-Amazon dataset of non-structural carbohydrate concentrations in leaves and branches. All of these datasets are critically important for better simulation the impacts of global change on Amazon forests.
First Year Of Impact 2016
Sector Environment
Impact Types Societal
 
Description ARBOLES: A trait-based Understanding of LATAM Forest Biodiversity and Resilience
Amount £1,356,155 (GBP)
Funding ID NE/S011811/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 02/2019 
End 01/2022
 
Description CAPES studentship to Julia Tavares (Project Team Member)
Amount £150,000 (GBP)
Funding ID BEX-1293/15-0 
Organisation Government of Brazil 
Department Coordination of Higher Education Personnel Training (CAPES)
Sector Public
Country Brazil
Start 09/2015 
End 09/2019
 
Description Leeds Climate Bursary Award to Julia Tavares for Additional Field Funding
Amount £2,000 (GBP)
Organisation University of Leeds Alumni 
Sector Charity/Non Profit
Country United Kingdom
Start 05/2018 
End 12/2018
 
Title Improved individual-based model with plant hydraulics 
Description TREMOR has led to the development of the TFS (Trait-based forest simulator) model to include a detailed treatment of plant hydraulic function. This will be further developed to link plant hydraulics with tree mortality. 
Type Of Material Computer model/algorithm 
Year Produced 2017 
Provided To Others? No  
Impact The model will be used to evaluate how diversity in plant hydraulic strategies within and across Amazonian forests influences ecosystem response to water stress. 
 
Title New analysis of the risk factors of tree death in Amazonia 
Description In TREMOR, we have conducted the first pan-Amazon analysis of the risk factors of tree death, including species-level risk factors (e.g. species mean growth rate and drought affiliation status) and individual-level risk factors (e.g. size). 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? No  
Impact This analysis has been submitted for review. The results provide valuable data for constraining the development of ecosystem models, with mortality processes being a current focus of development. 
 
Title Plant hydraulics traits for Amazonia 
Description Fieldwork conducted as part of TREMOR in Years 1 & 2 of the project has resulted in a substantial pan-Amazonian dataset of plant hydraulic properties and non-structural carbohydrates, that will, for the first time allow us to infer how vulnerability to drought varies across different Amazonian forests. In total, 16 different hydraulic properties were measured. 
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? No  
Impact Once complete and published, the dataset will be used by modelling groups to develop better model of drought-induced impacts on forest productivity and mortality. 
 
Description Collaboration with the Instituto de Investigaciones de la Amazonia Peruana 
Organisation Peruvian Amazon Research Institute
Country Peru 
Sector Charity/Non Profit 
PI Contribution IIAP is a core Latin American Project partner in ARBOLES, receiving CONCYTEC funding to establish climate-conditioned greenhouses to test the sensitivity of commercially sensitive tree species to temperature and water stress. The experimental set-up in IIAP mimics that being set up in our study site in Nova Xavantina, Brazil. Leeds has provided important inputs into the design of the greenhouse and the temperature regulation system.
Collaborator Contribution IIAP partners (Jhon Aguilar, Nallaret Davila, Euridice Honorio) have coordinated the construction of the greenhouse (now in place) and are currently undertaking germination studies to decide on the species for the first round of warming experiments. IIAP will also lead the data collection within the Peruvian experiments.
Impact No outputs yet
Start Year 2019
 
Description Global forest canopy temperature network NetCTF 
Organisation University of Plymouth
Department Psychology Plymouth
Country United Kingdom 
Sector Academic/University 
PI Contribution Involvement (Co-supervision) of PhD student who examining differences of canopy thermal regulation of high CO2 versus ambient CO2 exposure tree crowns at the BIFOR face experiment and who installed continuous measurement capability at a newly constructed tropical forest canopy overlooking tower in Ghana. Similar to other projects of ours the purpose of these measurements is to obtain a mechanistic understanding of limits of functioning of tropical forests.
Collaborator Contribution Measurements of canopy thermal regulation of high CO2 versus ambient CO2 exposure tree crowns at the BIFOR face experiment and installation of continuous measurement capability at a newly constructed tropical forest canopy overlooking tower in Ghana. Similar to other projects of ours the purpose of these measurements is to obtain a mechanistic understanding of limits of functioning of tropical forests.
Impact Work ongoing. Very interesting results with manuscripts in preparation.
Start Year 2021
 
Description Leeds (EGC)-CREAF 
Organisation Ecological and Forestry Applications Research Centre
Country Spain 
Sector Charity/Non Profit 
PI Contribution This collaboration is between the Leeds project team and Prof. Maurizio Mencuccini's lab in CREAF. Prof. Mencuccini co-supervises a student with me and TREMOR co-I Emanuel Gloor and will also participate in project fieldwork.
Collaborator Contribution Prof. Mencuccini and his lab provide incredibly valuable expertise on plant hydraulics. They have hosted the Leeds team in Barcelona for training in plant hydraulic measurements.
Impact This collaboration is very new - no TREMOR-related outputs have been generated yet.
Start Year 2015
 
Description Leeds - UNICAMP 
Organisation State University of Campinas
Country Brazil 
Sector Academic/University 
PI Contribution This is a new partnership, developed specifically through TREMOR, between the Ecology and Global Change research cluster and Department of Plant Sciences in the State University of Campinas (UNICAMP) to determine plant hydraulic properties across Amazonia. Researchers from Leeds and UNICAMP have conducted joint fieldwork through the partnership. Carol Signori from UNICAMP was awarded a studentship to spend one year in Leeds writing up papers from her PhD in Leeds. Additional ODA funding from TREMOR has also directly contributed to the training of a technician from UNICAMP. ODA funding tied to TREMOR has further allowed the training of a UNICAMP technician, Eduardo Kiyota, in cutting-edge isotopic analysis.
Collaborator Contribution UNICAMP has contributed with significant technical expertise in the measurement of plant hydraulic properties. More specifically, members of the TREMOR team spent time at UNICAMP learning a novel method for constructing xylem vulnerability curves, which has since been applied across all of our Amazonian sites.
Impact A PhD student at UNICAMP, Carol Signori, is currently in Leeds for a year following an award of a 1-year CAPES studentship. She is writing up three manuscripts which directly build on the Leeds/UNICAMP collaboration.
Start Year 2016
 
Description Leeds(EGC) - ANU(SoB) 
Organisation Australian National University (ANU)
Department College of Medicine, Biology & Environment (CMBE)
Country Australia 
Sector Academic/University 
PI Contribution TREMOR has directly contributed to recent grant applications by Prof. Meir by providing modelling expertise in forest dynamics, including forest sensitivity to drought. As a result of this collaboration, a Master's student from ANU (James Milner) has just completed a 1-month visit to Leeds to be trained in individual-based modelling.
Collaborator Contribution Prof. Meir is an expert in drought physiology who has led a throughfall exclusion experiment in Amazonia since 2002. He provides invaluable advice on field measurements made within TREMOR.
Impact Although the collaboration with ANU is novel, I have been collaborating with Prof. Meir for several years, while he was based in Edinburgh. This collaboration has resulted in various jointly authored publications, including some in high-impact journals such as Nature, Nature Geoscience and PNAS. These publications all pre-date the start of TREMOR.
Start Year 2015
 
Description TREMOR/Universidade Federal do Acre 
Organisation Federal University of Acre
Country Brazil 
Sector Academic/University 
PI Contribution TREMOR has enabled the training of a Masters student, Martin Acosta, at the Universidade Federal do Acre (UFAC), who are now developing independent MSc projects using the skills they acquired through involvement with TREMOR.
Collaborator Contribution Partners have provided invaluable logistical support for project field campaigns in Acre.
Impact Award of MSc stipend to Martin Acosta based on a project idea developed in collaboration with TREMOR staff.
Start Year 2016
 
Description Western Ghats tropical forest observation network 
Organisation Kerala Forest Research Institute
Country India 
Sector Public 
PI Contribution Dr. Sreejith Kalpuza runs a network of forest sites in Western Ghats Kerala, South of the site where we study tropical forest vulnerability to heat and drought. Together with sites run by Dr. Barua a large climatic gradient is covered which opens up to generalize our results along this gradient.
Collaborator Contribution Sharing of relevant data.
Impact Too early still.
Start Year 2021
 
Description Delivery of Climate Sensitivity workshop in Acre, Brazil 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact This workshop was run by a University of Leeds team (David Galbraith, Julia Tavares, Emma Docherty) at the Universidade Federal do Acre (UFAC), Brazil, in November 2019. At the workshop, postgraduate students were taught how to make key traits indicative of climate sensitivity (hydraulic and thermal traits), advanced analysis of trait data in R and the basics of ecosystem modelling with Python.
Year(s) Of Engagement Activity 2019
 
Description Ecophysiology workshop Sirsi, Indian Western Ghats 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Approximately 40 graduate and post-graduate students from all across India attended a 1 week tree ecophysiology workshop organised by the holder of the grant. It included theory, hands on training on instruments like LICOR, a two day project and presentation. The workshop was a success.
Year(s) Of Engagement Activity 2018
 
Description Invited Talk for International Tree Mortality Network 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact ~60 people attended the talk online, as part of a seminar series organised by the International Tree Mortality Network. The talk generated interesting discussion about best approaches to evaluate the sensitivity of tropical species to climate change.
Year(s) Of Engagement Activity 2022
URL https://www.tree-mortality.net
 
Description Invited talk Plant Ecophysiology Workshop Kerala Forestry Institute KFRI 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Postgraduate students
Results and Impact Invited talk
Year(s) Of Engagement Activity 2021
 
Description Live lecture to postgraduate students at the Universidade Federal do Pará 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact This was a live lecture, streamed via youtube, on the carbon cycle of Amazon rainforests and its sensitivity to climate and land use change. The lecture was followed by a Q&A session where students from across Brazilian universities engaged with the discussion.
Year(s) Of Engagement Activity 2020
URL https://www.youtube.com/watch?v=dkkpYz53GOo
 
Description Public lectures in Brazil (UFPA, INPE) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Undergraduate students
Results and Impact Two presentations given in Belem, Brazil, one at the Federal University of Para, the other at the Brazilian Space Institute on the topic of climate change impacts on Amazon forests, in which current TREMOR work featured prominently. Talks were attended by university and research staff, postgraduate students, undergraduate students and technical staff. Talks were followed by discussion on several aspects of the climate sensitivity of tropical forests. Further discussions were held about the possibility of establishing more formal links between the University of Leeds and the UFPA for hosting PhD students.
Year(s) Of Engagement Activity 2017
 
Description School Talk at Highfield Primary School 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact Interactive given to ~60 Year 4 students at Highfield Primary School, Leeds. The talk focused on the Amazon rainforest and why it is important for our planet. Students asked many questions about the Amazon and enthusiastically participated in discussion.
Year(s) Of Engagement Activity 2019
 
Description Training Workshop in Santa Cruz, Bolivia 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Undergraduate students
Results and Impact This was a 2-day workshop was held at Museo de Historia Natural Noel Kempff, focusing on training 15 undergraduate students in making measurements of plant hydraulics. This included guidance on making vulnerability curve measurements, stomatal conductance measurements and leaf water potential measurements. Training was also given in the preparation and collection of samples for analysis of non-structural carbohydrates and isotopic analysis of soil samples.
Year(s) Of Engagement Activity 2017
 
Description Training workshop in Iquitos 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Undergraduate students
Results and Impact This workshop was organised in IIAP (Instituto de Investigaciones de la Amazonia Peruana) by the TREMOR team to discuss potential climate change impacts on Peruvian forests and raise awareness of the importance of hydraulic measurements for understanding forest vulnerability to climate change. The audience was mainly undergraduate students with some postgraduate students involved. Some students were then trained in making plant hydraulic measurements and participated in the project campaigns in Alpahuayo and Sucusari, both close to Iquitos.
Year(s) Of Engagement Activity 2017
 
Description Tropical forests and the decline of the carbon sink talk 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact UK BEIS with many international attendees, Tropical forests and the decline of the carbon sink talk (virtual), Oliver Phillips
Year(s) Of Engagement Activity 2020
 
Description Workshop in Rio Branco, Acre 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact This 1-day workshop was organised and run by the TREMOR team at the Universidade Federal do Acre in Rio Branco, Brazil. It was attended by approximately 40 masters-level and undergraduate students. The team gave several talks on climate change impacts on forests and the importance of making measurements of plant hydraulic vulnerability. These talks were followed by hands-on teaching of several hydraulic measurements.
Year(s) Of Engagement Activity 2017