Research: Biodiversity
Oxford Long-Term Ecology Laboratory
Long-Term Ecological Research in Temperate and Tropical Regions of the World
Research in the Oxford Long-Term Ecology Laboratory focuses on the long-term relationship between vegetation dynamics and environmental change. We use the fossil record (pollen, plant macrofossils, charcoal, stable isotopes 12C/13C, 15N in conjunction with Pb210 and 14C dating) to reconstruct past vegetation dynamics in response to changes in climate (water/energy), atmospheric concentrations (CO2), soils (degradation, aggradation) and human impact. Increasingly we are committed as a group towards using the fossil record to examine relatively recent ecological change (past 2000 years or so) and the influence of human activity upon this change. Much of this work will be applied, thus examining specific 'ecologically critical regions' and providing essential long-term data for use in their management, planning and restoration ecology.
The Oxford Long-Term Ecology Laboratory is part of the Biodiversity Research Cluster in the School of Geography and the Environment.
Current Projects
Forest Conservation in a Changing World: using palaeoecology to improve the effectiveness of conservation planning in the Apuseni Mountain, NW Romania.
Dr Angelica Feurdean and Prof. Kathy Willis
Funded by the EU framework IV Marie Curie.
One region in Europe where there are still exceptionally large tracts of 'undisturbed' natural temperate forests is in Romania. In order to plan for the future management of some of the most biodiverse regions of Europe, it is essential that we understand their natural variability and probable response. The Apuseni Natural Park (PNAp) was founded in 1991 with the aim to protect the forests of the Apuseni Mountains and their high biodiversity containing a number of faunal and floral endemics and rare species. PNAp has been classified in 2001 as an IUCN (The World Conservation Union) 'class V' reserve with highly permissible policy in the management plan, allowing diverse human activities in the park (timber production, tourism, agriculture, encouraging traditional life style and economy). This project uses the palaeoecology and geochemistry to illustrate how the interaction between climate change, human activities and other disturbances have shaped the present landscape over thousands years. The results will provide managers with information that will help improve the effectiveness of conservation of PNAp habitats and its biodiversity. See also http://www.parcapuseni.ro
Restoring native biological diversity in the Galápagos Islands: determination of baseline ecological conditions.
Dr Cynthia Froyd, Prof. Kathy Willis, Emily Coffey and Alistair Seddon
Funded by the Natural Environment Research Council
The Galápagos Islands are a National Park, UNESCO World Heritage site and Biosphere Reserve and are globally renowned both for their ecological value and as a world symbol of scientific discovery. However, this unique region currently exhibits some of the highest extinction rates in the world, the result of extensive habitat degradation and widespread impact from non-native species since European colonisation. This project uses palaeoecological research techniques (fossil pollen, plant macrofossils, testate amoebae, diatoms, geochemistry, and stable isotopes) to reconstruct the long-term changes in the native plant communities and environmental conditions across the Galápagos archipelago. It provides conservation managers with long-term, historical baseline ecological data - information that is critical to the design of an effective program for the restoration of native biological diversity in Galápagos.
Highlights of Recent Research: The removal of non-native plant species in Galápagos has become a key conservation-restoration priority. Fossil pollen and plant macrofossil analysis from the last 8000 years shows that six presumed introduced or doubtfully native species are in fact native to the archipelago. These findings have significant implications not only for conservation in Galápagos, but for the management of introduced species and pantropical weeds in general. For more information on this research see: 'Fossil Pollen as a Guide to Conservation in the Galápagos', Science, 322: 1206 (Abstract / Full Text) An interview with Dr Cynthia Froyd is available via podcast on the Science website.
Climate and biogeochemical cycles during the last deglaciation.
Dr Shonil Bhagwat with Prof. Kathy Willis and Dr Mary Edwards, Southampton.
Funded by the Natural Environment Research Council's QUEST programme (part of a consortium led by Professor Paul Valdes, Bristol.)
Understanding the record of past changes to climate and biogeochemical cycles is one of the greatest challenges for the Earth System Science community. This project aims to develop new palaeoenvironmental syntheses describing changes in vegetation patterns, wetland distribution, and fire regimes, and changes in the terrestrial carbon cycle since the Last Glacial Maximum (LGM). The project will use two fast climate models (FAMOUS, GENIE-IGCM) to explore the consequences of changes in external forcing and biogeochemical feedbacks on the transient behaviour of climate from the LGM, through the deglaciation and into the Holocene. The Long-Term Ecology Laboratory together with the Palaeoecology Laboratory at the University of Southampton will compile pollen and plant macrofossil records from the northern extra-tropics to reconstruct changing vegetation patterns from LGM onwards, for comparison with simulated vegetation patterns.
[Image: Bigelow et al. 2003 (Journal of Geophysical Research, 108 (D19), 8170)]
The Northern Eurasian Macrofossil Database is now available to download.
Long-term forest dynamics in the Sierra de Manantlan Biosphere Reserve, Mexico.
Blanca Figueroa-Rangel and Prof. Kathy Willis.
The Sierra de Manantlan was made a biosphere reserve because of the incredibly high biodiversity of its forest mosaics and because it contains the wild ancestor of maize. However, it is not known if the present forest compostition and structure is part of a successional stage due to intensive utilisation by indigenous human populations in the past or if it is due to natural processes. The long-term forest dynamics are being reconstructed using tree rings and fossil pollen and microfossil charcoal analyses of sediments with the aim to help inform managers and contribute to the biodiversity conservation debate.
Island forest formation on Tenerife, Canary Islands.
Lea de Nascimento Reyes, Dr José María Fernández-Palacios and Prof. Kathy Willis.
The Canary Islands are rich in endemics and contain a number of distinctive vegetation types including possible relict Tertiary laurel forests. This project aims to determine the impact of past climates and human activities on the development of these diverse forest types. Fossil pollen and charcoal analyses from the former lagoon of La Laguna city will provide the first temporal perspective on the biogeographic development of this climatically critical region.
Habitat reconstruction of cave sites in the western Mediterranean during the demise of Neanderthals.
Steve Ward, Prof. Kathy Willis, and Dr Nick Barton.
Funded by the Natural Environment Research Council.
This study focuses on the reconstruction of vegetation dynamics at archaeologically important cave sites in northern Morocco and Gibraltar, using macrofossil charcoal and phytolith analyses. It forms part of a larger project investigating the local evolution and dispersal of archaic Homo sapiens, and the demise of the Neanderthals in the middle/late Palaeolithic.
Prehistoric human impact on the Central African rainforest.
Dr Terry Brncic, Prof. Kathy Willis, Dr David Harris and Dr Terry Dawson.
Funded by the Leverhulme Trust.
Recent research has shown that dense tropical rain forest may have once held larger human populations than it does today. What is the link between prehistoric human disturbance and contemporary forest structure in the Congo Basin? This study combines ecology, palaeoecology, remote sensing, and botany to determine both the spatial extent of prehistoric human disturbance as well as the long-term patterns of succession and the rate of vegetation and soil recovery.
Modelling late glacial / early post-glacial changes in nitrogen cycling and its impact on vegetation.
Elizabeth S. Jeffers, Prof. Kathy Willis, Dr Mike Bonsall, Dr Cynthia Froyd, Jenny Watson, Dr Steve Brooks, and Dr Hillary Birks.
Previous studies have demonstrated significant shifts in vegetation throughout northwestern Europe - particularly changes from coniferous to deciduous forests - during the late glacial / early post-glacial period of the Holocene, a period of major climatic changes. The role of nitrogen availability in vegetation changes during this period has not been analyzed before now. Data from the fossil record, such as pollen, carbon and nitrogen isotopes, sediment geochemistry and chironomids will be used in a deterministic ecological model that aims to identify the temporal relationships between climate change, rates of nitrogen cycling in soils and changes in vegetation.
Vegetation dynamics at a critical environmental threshold.
Prof. Kathy Willis and Dr Adam Kleczowski.
The Northern Hemisphere Glaciation (NHG), approximately 2.75 Myr was a time of critical environmental change in Earth's history with global cooling, increased aridity and the build up of ice-caps at the Poles. Research involves detailed analysis of an annually laminated sedimentary sequence from Hungary spanning 350,000 years between ~3.0-2.65 Myr. Results from this work are starting to provide for the first time a record of the rate, timing and response of vegetation change at this critical climatic threshold and the formulation of a new theory about the triggering mechanisms behind initiation of the NHG (Willis et al; 1999a; 1999b).
The impact of Neolithic farmers on the Hungarian landscape.
Prof. Kathy Willis, Pia Windland and Prof. Alisdair Whittle.
During the early Neolithic, archaeological evidence suggests that parts of the Great Hungarian Plain were densely occupied by the Körös culture. What was the impact on the landscape of some of Europe's earliest farmers? Did they initiate widespread clearance, changing the Hungarian Plain from the forest to its present-day open landscape? This project addresses these questions through detailed phytolith and pollen analyses of sedimentary sequences from two ox-bow lakes near Körös occupation sites.
The Kruger Environments Project.
Dr Lindsey Gillson
Funded by the Trapnell Fund.
Savanna ecosystems are dynamic; vegetation is influenced by complex interactions between edaphic conditions, herbivory, competition, climate, fire and human management at a range of spatial and temporal scales. Strategic Adaptive Management of the Kruger National Park, South Africa, is based on a heterogeneity paradigm, raising important questions for ecosystem management: Can habitat degradation be distinguished from background variability? What are the critical climatic thresholds and disturbances at which the ecosystems of Kruger park undergoes rapid change? At what point should managers intervene? Palaeoecological techniques are used to study vegetation change over time-scales of hundreds to thousands of years to investigate the role of climate, fire and disturbance in ecosystem dynamics.
Spatial and temporal vegetation patterns in Kruger National Park, South Africa.
Kristina Duffin and Dr Lindsey Gillson
Funded by the Trapnell Fund, Jesus College and University of Oxford.
Interpretation of fossil pollen records requires an understanding of the relationship between the percentages of pollen found in the fossil record and the spatial distribution and abundance of vegetation in the landscape. The project aims to simulate past landscapes based on fossil pollen counts, by comparing simulated pollen assemblages with actual pollen counts. By linking present day, decadal and palaeo time-scales in a nested hierarchy of temporal scales, this project refines the interpretation of palaeoecological data, thus facilitating its application in ecosystem management.
Fire history and long term vegetation dynamics in eastern Kruger National Park, South Africa.
Dr Anneli Ekblom and Dr Lindsey Gillson
Funded by the Andrew W. Mellon Foundation.
Fire is a main agent in shaping the heterogeneity of the savanna landscape and understanding the dynamics of fire ecology is important for the ecosystem management of Kruger Park. Through analysis of pollen, spores and microscopic charcoal particles the project will facilitate the understanding of the role of fires, natural and manmade, and its interaction with climate, herbivory and plant competition in shaping the savanna ecosystems of eastern Kruger and the adjacent Mozambique section over the long term. This understanding will be of importance for ecosystem management and will contribute to shaping policies of fire management in the future.
Long-term vegetation dynamics at the savanna-grassland boundary, South Africa.
Elinor Breman and Dr Lindsey Gillson
Funded by the Andrew W. Mellon Foundation.
The savanna-grassland ecotone consists of different vegetation assemblages at the limits of their environmental and competitive tolerance; it is therefore particularly sensitive to changes in climate and disturbances. This project aims to study the spatial and temporal changes in the savanna-grassland boundary and identify the position of climatic and disturbance thresholds. The project will contribute to the development of conceptual models which explore how feedbacks between climatic and anthropogenic factors can cause phase transitions in ecosystems and enable managers to intervene if ecological system or process is close to an intrinsic limit.
Using palaeoecology to address mining/conservation conflicts, Southeast Madagascar.
Malika Virah Sawmy, Prof. Kathy Willis and Dr Lindsey Gillson.
Funded by the Rufford Maurice Laing Foundation.
The littoral forest, ranked as high conservation priority, occurs along the eastern coast of Madagascar as small fragments. The assumption that people have fragmented the littoral forest has been used to support proposals for near complete removal for mining. However, little is known about the long-term ecology of the littoral forest. Have the forests always been fragmented, for example, or are the fragments a consequence of past sea-level rise, erosion processes or human disturbances? This project will combine palaeoecology, geochemistry and remote sensing to identify landscape-scale changes of the littoral forests over the past few thousand years. This information will be incorporated in a conservation management plan to improve biodiversity conservation.
The Ecological History of Sacred Groves in the Western Ghats, India.
Dr Shonil Bhagwat and Prof. Kathy Willis.
Funded by the British Ecological Society.
Sacred groves in the Western Ghats of India are small patches of forest protected by social tradition and religious taboo. What remains unclear, however, is whether they are an artefact of human management of the landscape or a relict of natural vegetation that was much more extensive in previous times. Using palaeoecological techniques this project aims to reconstruct the vegetation history of the sacred groves before, during and after human settlement; and provide the first detailed temporal study on the impact of cultivation in this cultural landscape.
Vegetation dynamics of Mongolia.
Luba Mandzy and Prof. Kathy Willis.
Funded by the Alliance of Religions and Conservation
The taiga and forest-steppe ecosystems of Mongolia are poorly understood, and there is debate over the role of humans and the extent of forest throughout the Holocene. This study aims to reconstruct the vegetation history of taiga and forest-steppe ecosystems of Monoglia using pollen, spores, charcoal and geochemistry. In particular, the goal is to understand how climate, people, fires and soil type influence vegetation dynamics, and how this landscape may evolve in the face of rapid environmental and social change.
Vegetation history and reconstruction of prehistoric landscape in North China.
Dr Yiyin Li, Dr Liping Zhou and Prof. Kathy Willis.
Funded by the Royal Society.
Archaeological investigations suggest that the Western Liaohe River Basin, located in southern Inner Mongolia, was one of the cradles of ancient Chinese civilization. Both agriculture and pastoralism have been important activities since human occupation around 8000 years ago. Long-term landscape conservation planning requires information about the 'nature' of this region. Has natural vegetation recovered or is the landscape a product of substantial and continued disturbance? This project aims to address this question using palaeoecological analyses. A special effort is made to identify plants associated with past human activities.