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Jessica Thorn

DPhil Candidate


Jessica’s research interests lie in the interface between conservation biology, agro-ecology, ecosystem services and functional diversity, human well-being and climate change adaptation. She is a 3rd year Dphil student in the Biodiversity Institute, University of Oxford under the supervision of Prof Kathy Willis, Dr Thomas Thornton (Environmental Change Institute) and Ariella Helfgott (Wageningen University). She holds an MSc in Environmental Change and Management at the School of Geography and Environment, Oxford University (2010-2011), Honours degree in Human Geography in the Department of Environmental and Geographical Science, University of Cape Town (2007- 2008) and Bachelor of Social Science majoring in Environmental and Geographical Science and Psychology from the University of Cape Town (2004-2007).

Her research draws from 7 years of working in agro-biodiversity community conservation in Southern Africa, West and East Africa, South Asia and Latin America. Prior to coming to Oxford, she worked with the London School of Economics, Brown University, and University of Cape Town. This has been grounded in practical fieldwork experience in the conservation sector in Southern Africa (2009-2010), in ecosystem-based adaptation and mitigation approaches for an alliance of conservation organizations called the Climate Action Partnership. During her masters (2011)  she interned  for United Nations International Strategy for Disaster Risk Reduction (Africa)  and the Red Cross Red Crescent Climate Centre in Nairobi, Kenya. She has conducted farmer exchanges in Nepal through the Farms of the Future Programme (2012) and trained agricultural extension workers and farmers  in Upper East and Western Ghana (2013/4) . She also has a strong interest in climate adaptation in economically marginalized peri-urban areas.


Climate change adaptation, ecosystem service and function and human well-being: The case of small-holder farming systems in South Asia and West Africa

Small-holder farmers play an influential role in prevailing environmental conditions across the globe. They maintain ecosystem functioning, through a configured matrix of crops housing a variety of pests and pollinators, and are concurrently major drivers of change through land clearance, river and ground water extraction, fertilizer inputs, and pesticide application. Two billion people depend on small-holdings for livelihoods, constituting 80 % of people living in sub-Saharan Africa alone. However, we have a limited understanding of how management practices impact ecosystem processes, goods and services such as nutrient cycling and decomposition, pollination services, pest and disease regulation or water regulation and supply. This is in part due to the lack of empirical data at the field level, and robust methods for assessing a range of services and their interactions.  Projected climate change impacts, together with population growth and changing consumption patterns, pose a serious threat to food production and livelihood security.  Solutions for sustainable intensification with few farming inputs are needed to promote the resilience of small-holders, and should be informed by robust analysis of empirical evidence of impacts now and in the future.

Against this background, the study seeks to address the following aims:

(1) Develop and trial an indicator-based field methodology to assess ecosystem processes, goods and services, and self-assessed human well-being in agricultural landscapes: Rapid Ecosystem Service Assessment Technique (RESAT).

(2) Conduct a systematic map of methodologies of grounded- ecosystem services assessments and their impact on agricultural land-management decision-making in developing countries.

(3) Assess ecosystem services of pest and disease regulation, pollination and decomposition along a climatic latitudinal gradient,  in terms of functional trait diversity, abundance and productivity.

(4) Quantitatively model the inter-linkages between ecosystem processes, goods and services and human well-being as a tool for resilient planning and decision-making.

(5) Recommend alternative land-management practices for small-holder famers in response to current and future climate change.

Methods used include space-for-time substitution, a robust multidisciplinary suite of methods for field assessment, taxonomic identification and multivariate modeling techniques. The study is grounded in the cases of rice cultivation in the Terai Plains of Nepal, and dry-season vegetable farming in Northern Ghana. This may provide rich information regarding impacts, as well as incentives for on-farm agro-biodiversity conservation.
Research projects

Rapid Ecosystem Service Assessment Technique (RESAT) : An indicator methodology  for assessing ecosystem processes and function, goods and services, and human well-being in agricultural landscapes

Collaborators: Dr. Carla Romeu-Dalmau , Ariella Helfgott and  Prof. Kathy Willis

Potential impacts of climate change on biodiversity and ecosystem function in small-holder agro-ecosystems in Northern Ghana

Collaborators:  Darren Mann, Dr. Jake L. Snaddon, Prof. Kathy Willis

A systematic review map on the impacts of different grounded ecosystem service assessments on agricultural land-management decision-making processes in developing countries

Collaborators:  Dr Gillian Petrokofsky and Wen Zhou (CIFOR)

Systemic Framework for Integrated Adaptation Planning (SIA)

Collaborators: Ariella Helfgott, Chase Sova, Abrar Chaudhury and Meghan Bailey


Thorn, J., Thornton, T. and Helfgott, A (2014) Autonomous adaptation to flooding in peri-urban settlements : Evidence of a growing culture of innovation and revitalization in Mathare Valley Slums, Nairobi. Forthcoming.

Helfgott, A., Bailey, M., Sova, C., Thorn, J., Chaudhury, A., Vervoort, J., Upraity, V., Ademiluyi, A., Kok, K. and Aggarwa, P. (2013) Changing Climates, Exploratory Exchanges and Farms of the Future: Nepal pilot study :  Exploratory exchanges build adaptive capacity of small-holder farmers in Nepal. Social technology and change . Forthcoming.

Thorn, J. and Oldfield. S. (2012) “A politics of land occupation:  a perspective on state practice and everyday mobilization in Zille Raine Heights, Cape Town”. Journal of African Studies, 46(5): 518-530. doi: 10.1177/0021909611403710.

Bourke, L., Butcher, S., Chisonga, N., Clarke, J., Davies, F, & Thorn. J. (2009) “Fieldwork stories: negotiating positionality, power and purpose”. Feminist Africa, 13 : 95-105.


Thorn, J. (2013) “Impact Evaluation for Farms of the Future , Nepal and SIA.”  CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) – Theme 1 Adaptation to Long-term Climate Change. Copenhagen, Denmark. October. Report.

Thorn, J. and Marais, S. (2010) “Lessons learnt from ecosystem-based approaches to climate change adaptation and mitigation in South Africa.” Prepared for Conservation International – South Africa. April. Report.

Thorn, J. (2009) State of substance abuse service delivery in the Western Cape. Prepared for the Provincial Government Department of Social Development, Sub-directorate of Substance Abuse. Cape Town. June. Report.

Thorn, J. (2008) “Urban Transformation and racial integration in Post-Apartheid South Africa – the case of Sybrand Park and Eastridge suburbs in Cape Town.” Prepared for the Department of Sociology of Brown University. November. Report.


“Measuring, mapping and modelling socio-ecological systems to inform local decision-making in agricultural landscapes.” Biodiversity Institute away day. Oxford, UK. January 2014.

“An indicator-based field methodology to assess ecosystem processes, goods and services, and self-assessed human well-being at the landscape level.” Biodiversity Resilience Symposium.  Oxford, UK. September 2013.

“Assessing the impact of climate adaptation strategies of small-holders on ecosystem processes, goods and services and human well-being .” British Ecological Society. Birmingham, UK. December 2012.

“Adapting to rising waters: A participatory investigation into community innovation in relation to urban flooding in Mathare Valley Slums, Kenya.” Sixth International Conference on Community-Based Adaptation. Hanoi, Vietnam. April 2012

“A politics of land occupation: State practice and everyday mobilization in Zille Raine Heights informal settlement, South Africa.” Intersections of Rights and Laws: Environment, Livelihood and Self – Determination conference. University of London. London, UK. January 2012.

“The policy project, research interface and road to adaptation.” Climate Action Partnership climate change knowledge exchange,  South African National Biodiversity Institute (SANBI). Cape Town, South Africa. October 2009.

“Challenging Evictions: Negotiating Lived Experiences in Zille Raine Heights.” Gender Justice and Body Politics International Conference. University of Cape Town in partnership with Brown University. Cape Town, South Africa.   February 2009.