Alpine Vegetation Changes

Research Project Briefing Note #1: An Integrated Assessment of the Impacts of Climate Change on Vegetation in the Victorian Alp

The reality of global climate change, and the effects of such change on ecosystems, is being increasingly supported by robust scientific data. The 20th century was the warmest for the past 1800 years, and since 1900 we have seen sea levels rise by 10-20 cm, snow and ice cover decline, and the distribution and phenology (the timing of seasonal events) shift in populations of plants and animals.

Rising global temperatures are likely to have extensive impacts on alpine environments globally. In Australia, alpine environments, along with high altitude tropical rainforests and the Great Barrier Reef, have been identified as being particularly at risk from the effects of global climate change, particularly rising temperatures.

Alpine environments in Australia are rare. They cover <1% of the continent, but despite this, they provide a wide range of goods and services. How are the soils, streams, plants and animals of these landscapes going to respond to climate change, and what will these responses mean for the water, soil and biodiversity resources that these landscapes provide to all Australians?

Project Aims and Intended Outcomes

To answer these questions we need information on the magnitude of predicted changes, the likely responses to these changes, the capacity of organisms, including humans, to adapt to change, and tools to both extrapolate research findings across landscapes and provide land managers with the means to assess the effectiveness of actual and proposed actions that aim to conserve the assets of the alpine region in the face of such change.

This project is designed to address these issues. The Project brings together a strong inter-disciplinary team of partners from several Universities, The CSIRO, SKI RESORTS, and the main Victorian Government agencies responsible for land management in the Victorian Alps.

The Project began in 2003, and there are three main components:

1. To experimentally warm the local microenvironment of a range of common alpine and subalpine plant species, and to document the responses of these species to changes in temperature.
2. To evaluate the genetic basis for survival and adaptive responses in key alpine species, and
3. To use mathematical models to explore the responses to climate change of the main alpine plant communities

The results of this research will inform land managers and planners about the range of options at their disposal to manage changes to protect critical elements of the alpine environment.

Research Project Briefing Note #2: The Responses of Alpine and Subalpine Plants to Increased Temperature

Climate change is upon us. The 20th century was the warmest century for the past 1800 years, and over this period snow and ice cover in mountain and polar regions declined. Rising global temperatures are likely to have extensive impacts on alpine environments across the world. However, the rates and directions of such potential change are generally unknown globally.

In this research project, we are using experimental field ecology, genetics and ecological modelling to address this issue (See Research Briefing Note #1 above). In the experimental field ecology part of the project, we are using growth chambers to warm the local environment of small patches of alpine grassland, and measuring the responses of the plants to such warming.

Project Aims and Intended Outcomes

The primary aim of the experimental part of the project is to warm the local microenvironment of a range of common alpine and subalpine plant species, and to document the responses of these species to changes in temperature and to changes in competition with neighbouring plants.

We are using an experimental protocol developed in the northern hemisphere for studying the impacts of climate change on alpine and polar ecosystems - the International Tundra Experiment (ITEX).

The ITEX program uses small (ca. 1-2m2) open-topped chambers (OTCs) or greenhouses, which passively warm air temperatures by 1-3o C. In the ITEX protocol, change in the phenology (leafing and flowering), growth and relative abundance (cover, height) of key, dominant species are measured. These are all important responses to climate change, and changes in response to experimentally altered climate have been detected in other ITEX experiments. Further details are on the ITEX website (http://www.itex-science.net).

This information will inform researches and managers about how rapidly different alpine plants may respond to rising temperatures, and which species may be most at risk from changing climatic conditions. The results of this research will provide information to land managers and planners about the range of options at their disposal to manage changes to protect critical elements of the alpine environment.

Further Information

Prof. Mark Burgman, University of Melbourne School of Botany
markab@unimelb.edu.au
Dr Dick Williams, CSIRO Sustainable Ecosystems
Dick.Williams@terc.csiro.au