A small answer to a big question. How do we measure climate change impact on forest ecosystems?
Written by Salina Abraham
It is well known that some of the most exciting parts to UN meetings are the side events. Today, IFSA’s partner IUFRO (International Union of Forest Research Organizations), held a side event on “Healthy forests for a prosperous environment: the multi-faceted aspects of forest degradation.” This event was held by the IUFRO Task Force on “Climate Change and Forest Health” with the intent to educate and improve understanding of interactions between forest and environment. In practice, this meant several scientists presented their findings in various topics related to climate change and forest health directly to policy makers and other stakeholders.
Of the many presentations – one that greatly interested me was a specific proposal of a global indicator on forests.
There have been robust discussions around the need to monitor and assess progress and of course, the importance of indicators to this end. Professor Christina Branquinho, from the University of Lisbon, underscored the need for global indicators not only on the drivers of climate change but also on the effect of climate change and the impact of adaptation and mitigation policies. Currently, indicators for forest health have revolved around measuring the number of species in an ecosystem and corresponding rates of extinction but she believes there’s a radically better way. The challenge – we need to measure the effects of climate change at the ecosystem level and somehow be able to see the impact of a 2 degree increase on different ecosystems (alpine and tropical for example) and on ecosystems with varying resilience.
Finding a global indicator that is observable at different scales and can reflect long term changes is not an easy task. But the indicator proposed made me smile – Professor Branquinho, suggested lichens.
The professor and her colleague walked us through the rationale for using lichens as a global indicator. First, lichens exist in almost all terrestrial ecosystems and have a long history of being used as indicators (for pollution and land use changes). Their value comes from the fact that they are directly controlled by the atmosphere, both temperature and precipitation. Additionally, there are standard methodologies in place to use them as indicators (2 used in practice, 1 by the US/Canada and the 2nd by Europe/Asia). Professor Branquinho’s team has proposed a framework to integrate these two methodologies and jointly analyze results to eliminate this issue. The team seeks to use changes in functional attributes (various shapes depending on different environments) rather than changes in species to measure effect. (functional diversity vs. species diversity)
As always, there are some challenges for interpretation on the global scale. The lichen respond to the most limiting factor of the environment, which could be sunlight, temperature, or precipitation depending on the environment. Currently, they have conducted studies in Brazil, Thailand, the USA and a few countries in Europe but the team is seeking to conduct pilot projects in more areas to fully assess feasibility. For now, it looks promising!
Do you see any problems with using lichen as indicators for ecosystem health or do you think that this is a great small answer to a big question? Let me know!