Understanding the thresholds for plant water use and water use efficiency (WUE) across tropical transition zones is critical for predicting how these key regions, which are high in biodiversity and provide significant ecosystem services, may respond to climate change. A primary goal of ECOSTRESS is to reduce the uncertainty in estimates of water use and WUE; when combined with ground-based data, this information can provide both a means of validation and an unprecedented opportunity to test novel hypotheses that provide predictive insights.
We will leverage a large and unique existing leaf trait (morphology, photosynthesis, albedo, chemistry, and stable isotopes) dataset from species sampled 1-ha plots in the ECOSTRESS ‘hotspots’ of transition zones of Ghana and Brazil. Because we collected samples from all of the species in each plot that composed 80% of the stand basal area, we are able to compare ECOSTRESS pixels to similarly sized plot-level community weighted means of water use efficiency and canopy temperature dericed from gas exchange measurements and leaf isotopes. We will establish the level of agreement between ECOSTRESS and field data in order to provide a measure of accuracy for ECOSTRESS data. In doing so, we will provide critical insights into how plant WUE and leaf temperature vary across tropical transition zones and test the extent to which there is evidence for thresholds associated with vegetation characteristics.


The team: this research is led by Dr Chris Doughty (NAU) and Dr Greg Goldsmith (Chapman University). Our research team has >10 years expertise working in these transition zones (Co-Is Oliveras and Malhi), extensive knowledge of ECOSTRESS (Co-I Fisher – ECOSTRESS science PI), and expertise in the field, remote sensed, and modeling methods.

The complex social-ecological dynamics surrounding forest fire in protected areas of the post-conflict Colombian Amazon demand innovative, practicable data science applications that yield useful insights for inclusive decision-making. Forest fires increasingly threaten Amazonian forests, which contribute to global biodiversity and climate regulation, functioning as a valuable carbon sink that is decreasing due to the effects of fires, deforestation and degradation. The resultant warming endangers local livelihoods by negatively affecting ecosystem services and water availability. Brazil’s recent conflagrations bring into stark relief the need for further research into sustainable alternatives to forest clearance, as well as greater attention to escalating deforestation in countries like Colombia, which contains 7% of the Amazon basin.
Our study analyses how social and ecological variables influence fire occurrence, as perceived by local stakeholders.
The project was co-led by Dr. Imma Oliveras Menor and Prof Dolors Armenteras (Universidad Nacional de Colombia), and the team Charlie Tebbutt (researcher), Maria Meza (researcher), Laura Cabildo (researcher), Tahia Devisscher (project partner), Ariel Ahearn (co-I).

More than 85% of the Brazilian area was originally covered by three biomes: the Amazon, the Cerrado and the Atlantic forest, all among the most biodiverse in the world. However, land use changes and deforestation have reduced this area to less than 60%, and much of the remaining vegetated areas sustain secondary and disturbed vegetation rather than primary vegetation. In addition, the climate is warming and drying, and the increasing occurrence of extreme heat and drought is already causing an increase in the flammability of forests. This project aims to answer the following questions: How will Brazilian forests change as a result of these stressors? Will undisturbed and regenerating forests respond differently? What is the role of biodiversity in mitigating or increasing their vulnerability to a drier, warmer and more flammable climate?

The team: I am co-PI, Principal Investigator (PI) is Dr. Simone Vieira (NEPAM, Unicamp, Brazil). Key project partners are Prof Rafael Silva Oliveira (Unicamp), Prof. Beatriz Schwantes Marimon (UNEMAT Nova Xavantina), and Dr Marina Correia Scalon (U. Oxford).

Finding source: THe project was fully funded by FAPESP (São Paulo, Brazil)

This is a pump-priming project that proposes the establishment of an experimental burning program with the aim of setting the grounds for a long-term research program on the fire effects on savanna ecology. After more than 35 years of a complete fire exclusion policy many regions of the Cerrado biome have suffered a substantial woody thickening and the more open savanna formations have disappeared. The experiment would be set in a unique area that has a fascinating rich mosaic of flora and fauna belonging to the Cerrado, Amazon and Pantanal Biomes. The main objective of this proposal is therefore to design and implement an experimental design composed by a series of permanent plots that will be subjected to fire with the aim of answering the following questions: i) how does a 35-year fire protected vegetation structure change after one fire? ii) what are the mortality rates of the main species responsible for woody encroachment after fire? iii) does fire allow the re-introduction of fire-dependant species?
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The team: THe project was co-led by Dr Imma Oliveras Menor and Prof Maria Antonia Carniello (UNEMAT), with the particpation Dr Wesley Jonatar da Cruz (postodcotral researcher) and ICMBio ( Marcelo Feitosa and Luiz Gustavo Goncalves).

In this project we validated the latest remote sensing products for this isolated region of the world. In the process, we established a new collaboration between the University of Oxford and Universidad Nacional de Colombia. ​At present, data is being processed and prepared for publication.

​The team: I was PI of this project ad Prof Dolors Armenteras Pascual was co-PI. Dr. Emma Gardner (Postdoctoral research assistant, U. Oxford), Jessica Grinter (research assistant, U. Oxford), Dr Sami RIfai (U. Oxford), Natalia Salazar (MSc student, UnCol).

Funding source: the project was funded by internal University of Oxford ESPRC-GCRF funds.

This projects spans the three largest biomes in Brazil, the Atlantic and Amazon Forests, and Cerrado savanna. Together these cover >85% of Brazil’s territory and include many of the most diverse ecosystems on Earth, but all have seen large losses in extent. While the value of their vegetation is increasingly recognised it is unclear to what extent these systems can regenerate or resist the increasing environmental stressors associated with climate change, particularly heating & drying. The motivation of BIO-RED is to understand how these changes affect the ability of intact & regenerating ecosystems to deliver societal benefits. This requires addressing these key questions: (i) How resilient are old-growth & regenerating ecosystems to the key stressors expected from future environmental changes? (ii) Is the destruction a reversible process on time-scales relevant to human society? Thus, will vegetation recover to a similar state as the original and provide similar services? (iii) Will the increasingly hot climate affect the recovery of forests and will modified forests be more vulnerable to future environmental change than intact forests? Answering these is only possible with a sound understanding how these systems function and what their sensitivities are.
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The team: I was co-PI. Other co-PI: Prof Oliver Phillips (U. Leeds), Prof Manuel Gloor (U. Leeds) and Fabien Wagner (INPE). Project collaborators: Prof Yadvinder Malhi (U. Oxford), Dr. David Galbraith (U. Leeds), Dr. Luiz Aragao (INPE), Prof Jos Barlow (U. Lancaster), Dr Marina Correa Scalon (U. Oxford), Prof Beatriz Schwantes Marimon (UNEMAT), Dr. Edmar Oliveira (UNAMET/U/Oxford), Dr. Erika Berenguer (U. Oxford), Dr Joice Ferreira (Embrapa), among others.

Funding: The project was funded by Newton Fund Program with funds allocated to FAPESP (Brazil) and NERC (UK).

This project with UNEMAT (Universidade Estadual do Mato Grosso) studied the functional coordination of vegetation types along the semideciduous forest-shrubland savannah gradient in the Cerrado-Amazon ecotone. This project was funded by the Brazilian Research Program Science without Borders (Ciência sem Fronteiras), which provided funds for the PhD research of Halina Jancoski (completed in 2019). It also funded Dr Marina Correa Scalon as postdoctoral researcher for 1 year, and Silvana Leme’s MSc research.

This project tested the fire suppression threshold in forest and savannah tree saplings through novel manipulative fire experiments in the forest-savanna transition in Ghana. It collected novel ecological information about differences in the establishment of savanna and forest saplings and their trade-off between fire tolerance and competitive ability. This work is published in Cardoso et al (2016) Ecology and Evolution

The goal of this Project was to develop tools for characterizing fire behaviour in TMCFs from the Peruvian Andes. Unfortunately, due to funding cuts the project could only be undertaken for one year. Nevertheless, results from that year are published in Pastor et al (2017) International Journal of Wildland Fire.

This project aimed to gather a detailed ecological and ecophysiological understanding of the dynamic process of tropical forest-savanna transition, at a number of sites of South America and Africa. The study was framed in the context of the forest-savanna fire thresholds from a functional trait perspective, with the aim of testing and further developing the role of fire and its interaction with drought and resources availability. This was achieved through detailed plot surveys to understand and quantify the tree mortality and recruitment processes,and through targeted manipulative experiments to understand and quantify responses to fire, drought, light and nutrient availability.