Tropical Savannas CRC > Publications > Savanna Links > Savanna Links Archive > Issue 12, November - December 1999

Issue 12, November - December 1999


Savanna landscapes: defining health

The tropical savannas are managed by people with different viewpoints, who want to know if they are managing the land well. Yet how do we know if the savannas are healthy when “health” depends upon your point of view.

Health workshops | Existing measures | A healthy savanna | How definition will be used |

Typical savanna landscape of grass, termite mounds and scattered trees

Savanna landscapes: to preserve their health, we first need to define what we mean by "healthy landscapes". Photo: CSIRO

Health workshops

The Tropical Savannas CRC recently held two workshops to develop definitions of what we mean by “healthy” savanna country. We have done this because if we want to conserve and use the tropical savannas in the long term, then we need a way of measuring how sustainably we are managing the savannas now, and what changes may need to be made in the future.

In other words we need a way of measuring how “healthy” the country is, where “health” is a measure of those properties in the landscape that people value and want to maintain into the future. Thus a healthy savanna landscape might have viable populations of native plants and animals, sustainable pastoral activities or intact Aboriginal cultural values or a combination of all three depending on the scale considered.

Existing measures of landscape health

There are already several measures of the “health” of the savannas but they tend to focus on a particular set of properties valued by a particular group of people. For example, pastoralists have developed measures of pasture productivity and sustainability; parks managers have developed measures of biodiversity conservation; and Aboriginal communities have long-standing measures of the cultural values of the landscape.

But each measure on its own may not be a satisfactory way of gauging the health of whole regions or catchments as these different values may conflict with each other. The workshops, which involved a varied group of land managers, planners and researchers came up with a broad definition of savanna health as follows:

A healthy savanna

  • Maintains basic functions at all spatial scales including:
  • nutrient cycling
  • water capture
  • provision of food and shelter for fauna
  • Maintains viable populations of all native species of plants and animals at appropriate space and time scales; and
  • Reliably meets the long-term needs (material, aesthetic and spiritual) of the people with an interest in the savannas over the long term.

Under this definition, a healthy landscape needs to have basic functions intact, such as the ability to effectively store nutrients like phosporous and nitrogen and capture moisture so that it can support pastures, native vegetation, traditional foods etc. Viable populations of all plants and animals native to that landscape are also necessary—perhaps not at the scale of paddock, but certainly at the scale of a catchment.

Over and above these biophysical characteristics a healthy landscape also needs to satisfy various human values such as the ability to graze cattle sustainably and the ability to support traditional Aboriginal practices.

How would this definition be used?

To use this definition, land managers and others need a set of indicators that would vary depending upon the scale considered. To measure health at the level of a paddock or a reserve only a few indicators might need to considered: such as the coverage of perennial grasses or a measure of biodiversity. But at the level of a catchment a range of indicators would be needed to cover basic functions, biodiversity, pastoral and Aboriginal values.

The TS-CRC has already coordinated considerable research on a range of potentially useful indicators and properties. A major task for the TS-CRC in the future is to refine an appropriate set of attributes or properties of the savannas that different user groups value—and a set of easy to measure indicators that tell us how we are managing these properties. The Centre has therefore sought the views of a wide range of people, with interests in savanna management, to describe the attributes of a healthy savanna and to identify ways in which those attributes can be measured.

In short, the aim of this exercise is to develop shared ideas about what features of the savannas are particularly important and need to be maintained over the long run, and to develop well-understood and widely-accepted methods for tracking how well we are doing.

Contacts

Dr Peter Jacklyn
NRM Networks Coordinator
Office of Research and Innovation
Tel: 08 8946 6285

Mobile: 0429 091 470
Fax: 08 8946 7107

Charles Darwin University
DARWIN, NT 0909


Dr Peter Whitehead
School for Environmental Research and TS-CRC
Tel: 08 8946 6703

Fax: 08 8946 6703

Charles Darwin University
DARWIN, NT 0909