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Research groupsGeographyCarbon Storage in Pasture through Ecological Restoration (CASPER)

Carbon Storage in Pasture through Ecological Restoration (CASPER)

Goals

Pasture with exotic grasses in Cerrado, Brazil.

Governments, companies, and individuals are increasingly investing and trusting in methods of removing carbon from the atmosphere in order to tackle climate change. But we still don’t properly understand how impactful many of these methods really are.  The Carbon Storage in Pasture through Ecological Restoration project (CASPER) seeks to address that knowledge gap, in relation to some specific Nature-based Solutions scenarios.

Working in Exeter and in Brazil, the CASPER team is studying what happens in soil to encourage carbon storage, and how long carbon will stay there once it’s stored. CASPER aims to substantially advance understanding of how plant-microbe soil interactions and agricultural management practices impact the potential for carbon sequestration.   

CASPER is novel because it links research into soil science to the challenges faced by local communities in the tropics, when attempting to implement restoration and regenerative agriculture in areas of severely degraded land. Specifically, it aims to create low cost, accessible ways to improve productivity and soil carbon storage using native plants, and at the same time improve economic and social outcomes for small scale farmers.  

Research to find affordable ways to store carbon, in harmony with nature and local people, is vital. Through the lab and field work, CASPER will provide demonstration sites and a body of scientific evidence about methods of soil management and restoration. This is expected to evidence methods that don't work, alongside the hope to find solutions that are viable, economical, and store carbon for the long term.  

Effective solutions to restore Brazil's vast areas of degraded land could benefit local communities, mitigate climate changes, and help to conserve and protect other natural resources in Brazil such as ground water.  

Link to Brazil

Underutilised and degraded pastureland are most concentrated within the tropics. Within Brazil, the world’s largest tropical country, pasture covers 21.5% of the country. Land management over the last few decades has severely decreased soil fertility and carbon stocks in these pasturelands, and as a consequence much of this land can no longer support either agriculture or grazing.  Around 54% of Brazil’s pasture are in moderate or severely degraded condition, representing almost 1 million km2 (almost twice the size of France).  

In these degraded lands, invasive species often out compete native flora, changing the landscape and making the restoration of native ecosystems increasingly difficult.  CASPER seeks to demonstrate a viable alternative to this scenario, in which these degraded lands could be more efficiently restored and utilised to increase carbon storage, biodiversity and social justice, whilst limiting the pressure to deforest native tropical habitats. Due to the vast areas at stake, even minor gains in improving degraded soils provide huge potential for positive biodiversity and societal impacts, and increased soil carbon storage. 

The main areas under study between the University of Exeter scientists and our Brazilian partners are in the Amazon arc of deforestation, and a savanna area called the Cerrado. The Cerrado is a vast biome with as many plant species as Brazil’s Amazon but is often overlooked in conservation, restoration and climate policy. 

Team

The team at the University of Exeter is comprised of 7 co-investigators, all based with the Geography department. Their expertise spans tropical ecosystem function and tropical plant diversity, soil science, biogeochemical cycles and greenhouse gas fluxes, microbiology, pastureland management, and the impact of land management practices on both carbon storage and local communities. Collectively, they have many years of experience conducting research in the tropics. 

The 5-year programme involves significant lab-based work in Exeter and fieldwork experimentation in Brazil, working with local partners, communities and land managers in the region. 

The field work will take place across various biomes in Brazil ranging from tropical rain forest to savanna, in close collaboration with researchers from the three partner institutions. 

  • Instituto Ouro Verde (IOV) – an NGO focused on social participation as a basis for sustainable development. 
  • Universidade Estadual de Campinas (UNICAMP) – a public research university in Sao Paulo 
  • Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) – a state-owned research corporation affiliated with the Brazilian Ministry of Agriculture. 

Methods

The research will cover three key areas. 

  • Identifying the mechanisms that can promote carbon sequestration in agricultural soils. 
  • Identifying solutions to increase productivity and soil carbon storage in degraded Brazilian pasture systems using native plants. 
  • Links and synthesis between these two elements. 

The Exeter based lab work will focus on microbial sequencing and analysis of soil / carbon interactions, within the context of growing varied plant species. The aim is to provide the mechanistic detailed understanding of plant, soil and carbon interactions, which can then be applied in the context of the Brazilian pasture lands (also with potential learning points for UK soils).  Much of the work will take place in a controlled lab environment, which enables the isotopic tracing of carbon into soil and study of the resulting greenhouse gas fluxes, within various soil, microbiome and plant combinations.  

The work in Brazil is conducted in partnership between the three Brazilian organisations and members of the Exeter team.  Areas of investigation include; the legacy effect of invasive species and chemical fertilizers on soil chemistry and soil microbial communities; the effect of native plant functional traits on soil properties; the potential of trees for hydraulic lift of water from deep soil layers; the effect of leguminous and non-leguminous trees on soil carbon and fertility; deep soil carbon stocks and the role of trees; the social and economic drivers of regenerative food production systems in the Cerrado and Amazonia.  

Funding

CASPER is funded by Shell. In their recently published Energy Transition Strategy (ETS) 2024, Nature Based Solutions are shown as one of the key enablers for carbon abatement and removal in the overall strategy roadmap (page 32)

CASPER stems from the understanding that the science behind net zero is clear, as is the need to accelerate the phasing out of fossil fuel supply and demand, transition to renewable energy at scale, and invest in carbon dioxide removal. This work is at the heart of the University of Exeter’s Strategy 2030. High-quality nature-based solutions, independently verified to determine their carbon impact and social and biodiversity benefits, will play an important and necessary role in mitigating global emissions. 

The CASPER Project provides a viable avenue for facilitating the scale and pace of change required, with potential for real world, global climate, ecological and societal impact. 

Infographic

Download the infographic.

CASPER infographic

Research capabilities in soil carbon and greenhouse gas dynamics

The CASPER programme brings together experimental and analytical capabilities to improve the quantification of soil carbon dynamics and their role in climate mitigation. Our work focuses on generating robust, high-resolution measurements of carbon cycling and greenhouse gas fluxes under controlled and field-relevant conditions.

A central component of this capability is the Exeter Soil Carbon Sequestration Laboratory (ExSEQ), which enables detailed investigation of plant–soil interactions, carbon inputs, and greenhouse gas emissions. Using controlled growth environments and advanced isotopic tracing approaches, ExSEQ supports the measurement of carbon flows from plants into soils and the partitioning of greenhouse gas fluxes at high temporal resolution.

These capabilities allow us to:

  • quantify small changes in soil carbon against large background stocks
  • measure continuous fluxes of CO₂, CH₄ and N₂O
  • distinguish between plant-derived and soil-derived carbon emissions
  • assess the impacts of land management practices, soil amendments, and agricultural interventions 

Our current capabilities are summarised in the document below and outlines the types of research questions that we are addressing within the CASPER programme.

We welcome opportunities for collaboration with academic and industry partners interested in advancing the measurement and understanding of soil carbon processes and their implications for climate mitigation.

Download the The Exeter Soil Carbon Sequestration Lab (ExSEQ) Infographic.

CASPER Academic Outputs, to January 2026

Laboratory Team 

Papers (Accepted and Under Review) 

  • Child, H.T., Friggens, N.L., Hook, C., Cressey E. L., Wierzbicki, L., Joslin, G.R., Dowdle J., Bore E.K., van Groenigen K.J., Tennant, R.K. & Hartley, I.P. Land-use driven microbial community legacy shapes soil functionality. Soil Biology and Biochemistry. Under Review 
  • Alathari, S., Barber, D.G., Bore E.K., Child, H.T., Wierzbicki, L., Joslin, G.R., & Tennant, R.K. Molecular Method for the Determination of Microbial Biomass in Soil. JoVE – Under Review 
  • Child, H.T., Wierzbicki, L., Joslin, G.R., Roper, K., Haxhiraj, Q. & Tennant, R.K. (2025) Automated environmental metagenomics using Oxford nanopore sequencing. BMC Genomics, 26; 835. https://doi.org/10.1186/s12864-025-11989-w  
  • Barber, D.G., Child, H.T., Joslin, G.R., Wierzbicki, L. & Tennant, R.K. (2024) Statistical design approach enables optimised mechanical lysis for enhanced long-read soil metagenomics. Scientific Reports, 14; 28934. https://doi.org/10.1038/s41598-024-80584-y  
  • Barber, D.G., Davies, C.A., Hartley, I.P. & Tennant, R.K. (2024) Evaluation of commercial RNA extraction kits for long-read metatranscriptomics in soil. Microbial Genomics, 10; 001298. https://doi.org/10.1099/mgen.0.001298  
  • Child, H.T., Wierzbicki, L., Joslin, G.R. & Tennant, R.K. (2024) Comparative evaluation of soil DNA extraction kits for long read metagenomic sequencing. Access Microbiology, 6; 000868.v3. https://doi.org/10.1099/acmi.0.000868.v3  

 

Abstracts/Posters presentations in scientific events 

  • Roper K., Child H.T., Joslin G.R., Wierzbick L. and Tennant R.K. Automation of Oxford Nanopore General Ligation LSK114 on the Agilent Bravo NGS Workstation (2025) SLAS - Hamburg, Germany - Poster 
  • Child H.T., Barber D.G., Joslin G.R., Wierzbicki L. and Tennant R.K.  Optimising metagenomic sequencing for soil microbiome structure and function (2024) ONT London Calling – London, UK - Poster 
  • Barber D.G. and Tennant R.K. Optimisation of soil RNA extraction for Nanopore Sequencing. (2024) ONT London Calling – London, UK - Poster 
  • Barber D.G. and Tennant R.K. Optimisation of soil RNA extraction for Nanopore Sequencing. (2023) ISMOS9 – Edinburgh, UK - Poster 
  • A. Medeiros, H. Child, P. N. Bernardino, P. B. Costa, E. S. Damasceno, N. J. T. Oliveira, C. C. Menegucci, A. C. Barbosa, L. Maracahipes-Santos, N. Pilon, R. S. Oliveira, F. Barros, L. Rowland, & R. Tennant. Soil fungal and bacterial diversity across pastures and native vegetation types of Brazilian savanna (2026) Savanna Meeting - Abstract 
  • Ezekiel K. Bore, Harry T. Child, Nina L. Friggens, Cheryl Hook, Elizabeth L. Cressey, Lucy Wierzbicki, John Dowdle, Richard K. Tennant, Kees Jan van Groenigen, Iain P. Hartley. Size matters: Fine biochar application mitigates N2O emissions during extreme drying and rewetting events in arable soils (2026) - EGU Abstract 
  • Gamage K., Bore E., Friggens N, Hartley I,P and van Groenigen K.J. Fate of newly added carbon and priming effects with biochar additions (2026) - EGU Abstract 
  • Alathari, S., Barber, D.G., Bore E.K., Child, H.T., Wierzbicki, L., Joslin, G.R., & Tennant, R.K. In-field monitoring of airborne biodiversity using a passive sampler (2026) - EGU Abstract 

 

Brazil Field team, and Partners Unicamp, Embrapa and IOV 

Papers (Accepted and Under Review) 

  • Aguiar, T.S., de Souza, A.P.R., Olival, A.A., de Oliveira, R.E., de Morais, J.P.G., Campana, M., Abdala, A.L. Contribution of Chloroleucon acacioides to soil fertility and forage quality and availability in Amazonian pastures. Acta Amazonica. Under Review 
  • Mouzinho, J.S.N., Olival, A.A., de Oliveira, R.E., de Morais, J.P.G., Campana, M., Abdala, A.L., da Silva Aguiar, T.S.N. (2025). Potential of Samanea tubulosa trees to improve forage quality and soil fertility in silvopastoral systems for the Amazon. Land Degradation & Development. Under Review 
  • de Morais, J.P.G., del Valle, T.A., Campana, M., Sobires, P.D., Hamerski, M.E.P., Olival, A.A., Amazon fruits of Chloroleucon acacioides improve the performance of heifers. Tropical Animal Health and Production, Under Review 
  • Jardim, R.I.L., Paumgartten, A.E.A. Bijos, N.R., Santos, P.P., Oliveira, R.O., Araujo, G.S.M., Bruziguessi, E., Silva, T.R., Scariot, A.O., Vieira, D.L.M., Rowland, L., Pennington, R.T., Barros, F.de.V. Native woody flora found in Cerrado pastures and their contribution to provisioning ecosystem services. Agriculture Ecosystems and the Environment, Under Review 
  • Pérez-Márquez, S., Ovani, V., Meira, V.E. et al. (2025) Assessing the impact of Samanea tubulosa trees on methane emissions and its potential as a feed supplement for ruminants in silvopastoral systems. Agroforest Syst 99, 135. https://doi.org/10.1007/s10457-025-01231-7 

 

Abstracts/Posters (accepted and presented)            

  • SILVA, A.C, FIAMETI, D., OLIVAL, A.A., MORAES, J.P.G. Influence of Apeiba tibourbou aubl. on forage availability in pastures of the southern amazon (2025) XII Seminar on Biodiversity and Amazonian Agroecosystems, Alta Floresta, Brazil – Extended abstract. 
  • PEREIRA, R.M, OVANI, V., OLIVAL, A.A, GHISLERI, E.B., ZORTEA, K.E.M. Contribution of native trees to soil chemical attributes in a silvopastoral system in the Southern Amazon (2025) XII Seminar on Biodiversity and Amazonian Agroecosystems, Alta Floresta, Brazil – Extended abstract. 
  • de Oliveira, A.C.C., Pilon, N., Stein, B., Cortês, C., Barbosa, A.C., Menegucci, C., Rowland, L., Oliveira, R.S. Leveraging species traits of disturbance-resilient ecosystems to make them available for restoration (2025) The 11th World Conference on Ecological Restoration, Denver, USA – poster. 
  • de Oliveira, A.C.C., Stein, B., Barbosa, A.C., Menegucci, C., Rowland, L., Oliveira, R.S., Pilon,N. Enhancing ecological and economic benefits through restoration of tropical grassy biomes (2025) The 11th World Conference on Ecological Restoration, Denver, USA – oral presentation 
  • Stein, B., Pilon, N, de Oliveira, A.C.C., Loaiza, J.P.N., Barros, F.V., Barbosa, A.C., Rowland, L., Oliveira, R.S. What are we losing regarding belowground structure richness when converting native areas into pastures in the Brazilian savanna? (2025) The 11th World Conference on Ecological Restoration, Denver, USA – poster 
  • Pilon, N, Stein, B., de Oliveira, A.C.C., Barros, F.V., Loaiza, J.P.N., Barbosa, A.C., Costa, P.B., Rowland, L., Oliveira, R.S. Consequences of land conversion to underground carbon storage in tropical open ecosystems (2025) The 11th World Conference on Ecological Restoration, Denver, USA – oral presentation 
  • de Oliveira, N.T., Costa, P.B., de Medeiros, A.S., Pilon, N., Rowland, L., Oliveira, R. Germination and establishment capacity of an invasive grass species in different Cerrado soils (2025) 75o Congresso Nacional de Botânica, Piauí, Brazil – poster 
  • MEDEIROS, L.R., ROWLAND, L., BARROS, F.V., OLIVAL, A.A., JAMES, E., PENNINGTON, T. Differential nutrient allocation in woody legumes in response to nitrogen fixation in tropical silvopastoral system. (2025) 61st Annual Meeting of the Association for Tropical Biology and Conservation, Oaxaca, Mexico – poster 
  • MEDEIROS, L.R., ROWLAND, L., BARROS, F.V., OLIVAL, A.A., JAMES, E., PENNINGTON, T. Nitrogen fixation and leaf allocation in different legume species in a silvopastoral system in the Amazon (2025) British Ecological Society Annual Meeting, Edinburgh, UK - poster 

 

Other outputs 

Videos 

  • de Azevedo Olival, J. Siqueira Nunes, Mouzinho, Thalyta Suellen, Nina da Silva Aguiar, Vanderson Eliel Meira. Trees and pastures: Amarelinho (C. acacioides): https://www.youtube.com/watch?v=kZ8qYnsIiRw  
  • de Azevedo Olival, J. Siqueira Nunes, Mouzinho, Thalyta Suellen, Nina da Silva Aguiar, Vanderson Eliel Meira. Trees and pastures: Bordão de Velho (S. tubulosa): https://www.youtube.com/watch?v=iCU6NAtzAd8 

 

Technical guides: 

  • de Azevedo Olival, R. Anderson Felito, M. Leandro Garcia. 2025. Manejo de árvores em sistemas silvipastoris. Editora UNEMAT.  ISBN 978-85-67216-03-4 
  • de Azevedo Olival, R. Anderson Felito, A. F. Gasparetti Ortali, J. P. Gomes de Moraes. 2025. Planejamento de sistemas de pastejo rotacionado e sistemas silvipastoris. ISBN 978-85-67216-04-1