Ecosystem pressures

I asked Professor Lindsey Gillson, an ecologist studying the long term conservation of ecosystems, about her concerns regarding the Anthropocene. The extinctions of modern biota are being caused by factors such as habitat loss, habitat fragmentation and degradation. There are also problems with pollution and, of course, climate change.

Losing one species can have disastrous knock-on effects for other parts of the ecosystem – ‘trophic cascade’ where for example, the loss of a pollinator can lead to the collapse of other species. There is an increasing recognition about the delicate balance of ecosystems – watch this video about the re-introduction of wolves into the Yellowstone National Park.

These observations can remind us how dynamic ecosystems are – a particular challenge facing those interested in restoration work. How do we choose which point in the past to ‘restore’ to?

The paleo-records of the past can help us immediately by giving an idea of what our world has experienced with warmer climates – a 1000 years ago (Medieval Warm Period) and 6000 years ago (mid-Holocene multi-thermal). Although imperfect, we can see how the ecosystems responded to the higher temperatures. Using the data about the past can also help scientists to build models about how temperature affected ecosystems – getting these to accurately plot what did happen is a great test for the tools we will need to develop for future scenarios of ecosystem change.

Despite the serious threats facing our ecosystems, Prof Gillson was very optimistic about the possibilities for reducing destructive human behaviour. What do you think?