
Sophie Jane Tudge
About
My research project
Assessing and projecting the effects of global land-use change for agriculture, forestry and bioenergy on biodiversityLand-use change for agriculture is a major driver of biodiversity loss. However, food security is of growing concern and there is also potential to generate renewable energy from crops and tree plantations in the form of bioenergy. To tackle the interrelated biodiversity and climate crises, while ensuring food and energy security, there is an urgent need to understand how land can be used to provide food, energy and resources, while both conserving and restoring biodiversity.
I am investigating the effects on biodiversity of land-use change for agriculture and forestry, in particular for bioenergy, and the local- and landscape-scale factors that are involved. I am using ecological and geographic data, describing local biodiversity and environmental and agricultural variables, to explore biodiversity patterns and trends in croplands and plantations. I am also using projections for land-use change and biodiversity to help design more sustainable landscapes that are compatible with biodiversity conservation, food security and renewable energy generation in the future.
Supervisors
Land-use change for agriculture is a major driver of biodiversity loss. However, food security is of growing concern and there is also potential to generate renewable energy from crops and tree plantations in the form of bioenergy. To tackle the interrelated biodiversity and climate crises, while ensuring food and energy security, there is an urgent need to understand how land can be used to provide food, energy and resources, while both conserving and restoring biodiversity.
I am investigating the effects on biodiversity of land-use change for agriculture and forestry, in particular for bioenergy, and the local- and landscape-scale factors that are involved. I am using ecological and geographic data, describing local biodiversity and environmental and agricultural variables, to explore biodiversity patterns and trends in croplands and plantations. I am also using projections for land-use change and biodiversity to help design more sustainable landscapes that are compatible with biodiversity conservation, food security and renewable energy generation in the future.
News
In the media
ResearchResearch interests
My research interests include:
- Biodiversity conservation
- Sustainable agriculture
- Land-use change
- Biodiversity monitoring
- Bioenergy
- Tropical forest ecology
Research interests
My research interests include:
- Biodiversity conservation
- Sustainable agriculture
- Land-use change
- Biodiversity monitoring
- Bioenergy
- Tropical forest ecology
Publications
Few studies explicitly assess the robustness and practicality of occupancy analysis informed by local inhabitants, compared to estimates from conventional monitoring methods within different contexts. This study evaluates the efficacy and robustness of occupancy models based on camera trap data, and two locally informed methods: seasonal interviews and hunter diaries, for monitoring 13 hunted mammal species in south-eastern Cameroon. We triangulate estimates of detectability and occupancy to assess the precision and comparability of their estimates for different species, and their cost. Camera trap estimates are comparable with estimates from locally informed methods in 7 of 11 available cases, but produced the lowest detection probabilities for all species in both villages. While camera traps provide robust estimates for abundant species with a high detection probability, locally informed methods can provide estimates of occupancy comparable to camera trap estimates, but at significantly less cost. They are particularly useful where camera trap detection rates (p) are too low to produce robust occupancy model estimates, notably for rare or cryptic species. The methods, survey effort and animals that can be monitored robustly vary between villages. As such, consideration should be given before monitoring commences to ensure that the most effective and informative approach is used.
Human activity in African tropical rainforests continues to threaten wild mammals. Many rural communities are dependent on hunting, yet there is a widespread lack of baseline data on ecology and the sustainability of hunting. We investigated the impacts of human activity on mammal species composition and distributions within a community forest surrounding a village in the buffer zone of the Dja Biosphere Reserve in south-east Cameroon. We conducted a camera-trap survey in August–November 2017 and detected 24 mammal species, including Critically Endangered western lowland gorilla Gorilla gorilla gorilla, Endangered central African chimpanzee Pan troglodytes troglodytes and Endangered tree pangolin Phataginus tricuspis. We used occupancy analysis to explore relationships between indicators of human activity (distance to a road and the Reserve), habitat quality (distance to the river and tree cover) and the distributions of species. We found that the local distribution of threatened mammals was not apparently limited by human activity, and proximity to the road did not negatively influence occupancy for any species. However, most of the Reserve's large species were not detected, including the African forest elephant Loxodonta cyclotis and the largest ungulates, and the occupancy of two species commonly hunted for wild meat was positively correlated with distance from the village, indicating hunting may be unsustainable. Our results show that the community forest provides habitat for threatened species outside the Reserve and in close proximity to people. However, effective conservation management will require continued monitoring and research to determine whether current rates of hunting are sustainable.
Concerns about the impacts of climate change have led to increased targets for biofuel in the global energy market. First-generation biofuel crops contain oil, sugar or starch and are usually also grown for food, whereas second-generation biofuel is derived from non-food sources, including lignocellulosic crops, fast-growing trees, crop residues and waste. Biofuel production drives land-use change, a major cause of biodiversity loss, but there is limited knowledge of how different biofuel crops affect local biodiversity. Therefore, a more detailed understanding could inform more environmentally-conscious decisions about where to grow which biofuel crops. We synthesised data from 116 sources where a potential biofuel crop was grown and estimated how two measures of local biodiversity, species richness and total abundance, responded to different crops. Local species richness and abundance were 37% and 49% lower at sites planted with first-generation biofuel crops than in sites with primary vegetation. Soybean, wheat, maize and oil palm had the worst effects; the worst affected regions were Asia and Central and South America; and plant species richness and vertebrate abundance were the worst affected biodiversity measures. Second-generation biofuels had smaller, but still significant, effects: species richness and abundance were 19% and 25%, respectively, lower in such sites than in primary vegetation. Our models suggest that land clearance to cultivate biofuel crops reduces local biodiversity. However, the yield of biofuel from different crops influences the biodiversity impacts per unit of energy generated, and the geographic and taxonomic variation in effects are also relevant for making sustainable land-use decisions.