The role of ecologists in a changing world

By Rebecca McLeod 25/02/2010

I have always believed that we need to work hard to try and keep things as they are – to keep the environment in a ’natural state’. But perhaps as the world we live in begins to change dramatically, so too should my thinking. I recently attended a seminar by Professor Terry Chapin, President Elect of the Ecological Society of America. Professor Chapin told the audience, who were mostly ecologists, that we need to shift our mindset — we need to start thinking of ways that we can modify the landscape to make humans more resilient to a changing climate.

Professor Terry Chapin, President Elect of the Ecological Society of America
Professor Terry Chapin, President Elect of the Ecological Society of America

Whilst public debate continues about the validity of the science in the IPCC reports, animals and plants – apparently oblivious to all the chit chat – are changing their distributions on a massive scale. As the climate warms, butterflies, sea urchins and fishes, to name just a few, are moving further towards the poles. Marine animals are inhabiting deeper depths as water warms, and land plants and animals are living at higher altitudes. Along with these shifts in range come implications for humans – inevitably we will be forced to change the way we fish, hunt, farm, obtain water and interact with our environment.

Professor Chapin has been working in the Alaskan interior, investigating the effects of wildfires on forests and the humans who live among them. Wildfires are naturally occurring in these parts and have been a feature of the region for at least the last 6000 years. But what has changed recently is the frequency and intensity of the fires, with lots of fires breaking out in ever more common hot, dry years. Another shift over the past few decades has been the movement of indigenous people from small, nomadic communities, to larger more permanent towns. Where once, people used to move in response to fires, the fires now have the potential to cause major disruption and threat to communities.

There are two main forest types in the Alaskan back blocks — black spruce, which is fire prone and is associated with permafrost, and broadleaf forest, which is less flammable. After particularly severe fires in black spruce forests, broadleaf forests tend to regenerate. However, in some of the drier regions, it is possible that forest may not regenerate, with the land converting to grassland. And so it seems likely that the Alaskan landscape is likely to change dramatically in the future if the high frequency of wildfires continues. Large scale changes in plant coverage like this will affect numbers and distribution of wild animals such as caribou, which provide an important food source. The indigenous people are strongly linked to the land and the landscape is set to drastically change.

Fire consumes black spruce forest
Fire consumes black spruce forest

Professor Chapin is proposing that Alaskans take an active role in modifying the landscape around them, to protect them from the consequences of wildfires. Maybe this could involve harvesting forests that surround townships to decrease the fire risk. Fighting fires is an expensive business — perhaps large scale changes in landuse could lower the costs.

I have to say that these ideas make me more than a little uncomfortable. Maybe it’s my inner tree-hugger coming out… Surely the ESA aren’t encouraging us to cut down forests?! A quick read of a recent position statement from the society ’Ecosystem Management in a Changing Climate’ was somewhat comforting.

’Ecosystems are already responding to climate change. Continued warming–some of which is now unavoidable–may impair the ability of many such systems to provide critical resources and services like food, clean water, and carbon sequestration. Buffering against the impacts of climate change will require new strategies to both mitigate the extent of change and adapt to changes that are inevitable. The sooner such strategies are deployed, the more effective they will be in reducing irreversible damage.

Ecosystems can be managed to limit and adapt to both the near- and long-term impacts of climate change. Strategies that focus on restoring and maintaining natural ecosystem function (reducing deforestation, for example) are the most prudent; strategies that drastically alter ecosystems may have significant and unpredictable impacts.’

It seems that the extent to which we should physically modify landscapes (versus allowing changes to occur without intervention) will need to be assessed on a case by case basis. One thing that is certain is that ecologists have a vital role in predicting future ecosystem-level changes, and advising how to make humans more resilient to changing environments. The role of the ecologist is moving beyond describing ecosystems and investigating how they function. Ecologists will increasingly be turned to for guidance on adaptive solutions to climate change.