The waters off the Australian coast contain all sorts of sea life. You may see a sea-horse, a sea-star, a sea-urchin or sea-squirt; definitely some seagulls, sea-shells, sea lettuce and seaweed. And, if you wait long enough, you may even see a sea-cucumber, sea-turtle, sea-lion and seal.
We value this diversity in its own right. With our children, we gaze in rock pools at a spectacle that took millions of years to evolve.
We also value diversity for practical reasons. Diverse ecosystems are more stable and productive than poor and degraded systems. They are better at resisting invasion by unwanted exotic species.
Diverse ecosystems provide ecosystem services that benefit humans, like filtering water and storing carbon. And diversity – from invisible genes to gigantic ecosystems – is the seed of future adaptation and evolution. Diversity begets diversity.
In helping nature adapt to a new climate, our fundamental goal is to ensure that all of our actions create diverse, self-sustaining ecosystems. This sounds obvious, but some practices that we considered useful under a stable climate – such as restoring historical ecosystems and planting local species and local genetic stock – may constrain or reduce diversity under a new climate.
We can inject diversity into our activities in many different ways. A key way to promote diversity is to work with people with varied values, backgrounds and skills.
There will always be a lot of uncertainty about how the climate will change in each region, and how society and nature will respond to a new climate. Given this uncertainty, we should always strive to do things in more than one way instead of putting “all our eggs in the one basket”.
And of course we want “no regrets” approaches that don’t paint us into a corner and reduce options in the future. We really don’t know how lots of things will work out, so we need to keep as many options open as we can.
When animals from one isolated population of the endangered Mountain Pygmy Possum were crossed with animals from another population, their genetic diversity increased, the females had more offspring and the size of the population increased.
New research on Australia’s threatened mammals has shown that isolated groups of animals tend to have distinctive genes. This distinctiveness came about when the populations became isolated and could no longer inter-breed; the genetic diversity within the isolated populations declined. Each population now has less potential to adapt and evolve in the future; which is a big problem under a changing climate.
We can promote genetic diversity in isolated populations of animals and plants by connecting habitats so that animals and plants (and their seeds and spores) can move across landscapes. We can also introduce plants and seeds from nearby hotter and drier areas into local areas, to create “climate-ready” populations.
We can maintain distinctive habitats in each region by selecting species from close to the planting area instead of using plants from other parts of Australia or the world. Diverse, self-sustaining populations and ecosystems are a key to helping nature adapt to climate change.
This content is adapted with permission from text written by Dr Ian Lunt for the VicNature2050 booklet 10 things we can all do to help nature adapt to a new climate.
VicNature2050 was organised by the Victorian National Parks Association, The Royal Society of Victoria and The University of Melbourne’s Bio21 Institute, and supported by the Victorian Department of Environment, Land, Water and Planning and Parks Victoria.
Other organisations who have participated in the VicNature2050 partnership include La Trobe University; Deakin University; Greening Australia; and the Arthur Rylah Institute for Environmental Research.