Paulina Varova | Lichens as natural air quality indicators: A study of species distribution across Urban, Peri-urban, and Nature Reserve sites in Gibraltar

MSc in Environmental Science & Climate Change

Image of Paulina Varova | Lichens as natural air quality indicators: A study of species distribution across Urban, Peri-urban, and Nature Reserve sites in Gibraltar

Research Project Overview

“My project aimed to determine whether lichen populations in Gibraltar can act as air pollution indicators. Overall, three sites across urbanisation gradient in Gibraltar were selected: Urban, Peri-urban and Nature Reserve. Three location from each of these sites, ranging from northern, mid-town and southern parts of Gibraltar were selected and analysed for lichen percentage covers, across three transects per each location, using a 25×25 cm quadrats spaced every 5 metres per transect (4x). Photographs of these quadrats were taken using a camera and with a standardised distance of 30cm of the quadrat from camera. This footage was then analysed for percentage cover per each species present within the quadrat, using PhotoQuad software. The data were then analysed using Excel and R studio. Results show overall higher lichen abundance in Nature Reserve, indicating high air quality compared to Urban and Peri-urban sites. Additionally, species which are considered pollution-sensitive and pollution-tolerant have been identified and used to determine the pollution levels across urbanisation gradient in Gibraltar.”

  • Primary Supervisor: Dr Awantha Dissanayake
  • Secondary Supervisor: Jemila Mellin

What type of research has it involved and what skills have you learned?

It has involved field-based surveys, using quadrats to measure lichen abundance, and statistical analyses to calculate the percentage covers. I have gained strong field-based surveying skills, specifically working with quadrats and environmental meter to collect environmental data (temperature, humidity, noise levels and light intensity). Additionally, I have gained significant data management and data analysis skills, working with number of statistical programmes.

Were there any partners/stakeholders on your project?

I was led by Leslie Linares, who has helped me to identify lichen species and define my methodology. Additionally, Leslie has provided photographs of lichens to help me identify the species and guided me throughout the research project period.

Why should the public know about this topic?

There is a lack of knowledge about lichens, not only in Gibraltar, but globally, people are not generally interested in lichens and often do not even recognise them. I believe lichens are very powerful especially for air quality indication and I also believe that with more awareness about lichens and their capabilities, general public would gain natural interest not only in lichens’ biology, but especially in air pollution.

What is the wider impact of your research?

This study may serve as a baseline for other, maybe more comprehensives studies, specifically incorporating chemical analysis. This way, some species may be used as highly valuable indicators and may assist in pollution reduction measures, not only in Gibraltar.

Keywords

Callinectes sapidus; marine invasive species; Mediterranean Sea; Gibraltar; citizen science; early detection; BRUV surveys; marine monitoring; stakeholder engagement; invasive species management.