Integrated land use decision tools

Imagine it is 1835. Imagine I am John Batman. Now the record tells us that Batman was a murderous, syphilitic drunkard, so I hope this does not tax your imagination overmuch. I am exploring the unknown country around Port Phillip, having sailed there from Launceston in the Rebecca for that purpose. It is the evening of 8 June, and I write in my journal that on the previous day I explored 'a large river' which we now know as the Yarra, and I note rather prophetically that 'This will be the place for a village'.

Now a Queenslander like Senator Parer or me might suggest that exporting the likes of Batman to Port Phillip might improve the quality of both regions. And a Sydneysider might agree with John Pascoe Fawkner, who actually established the infant settlement later that year on the northern side of the river, rather than the southern side that Batman favoured. All right thinking Sydneysiders would know that any move closer to Sydney could be no bad thing in improving Melbourne.

Now what is going on here?

What is Batman doing? He is making a land use decision. He has collected some data about the nature of the land through his explorations, compared them against his needs, and come to a decision.

And what are we doing? We are second guessing that decision, just like Fawkner did. We are looking at Batman's decision and then comparing it against our needs and coming to a different conclusion from Batman himself.

This vignette describes nearly everything we need to know about land use: it requires information, it leads to a decision and it can cause reasonable people to disagree.

In this talk I want to look at each of these three in turn and see what it might mean to get better information, make better decisions, and have less disagreement.

Land use is the oldest issue of all ...

But before I dive into this argument, I want to offer a broader perspective from which, I argue, we should view the problem of land use. I would like you to draw back a little from the concerns of the last years of second millennium, and look at the problem of land use as a problem of all of human history, and perhaps even pulling further back, as a problem of all living things. From this perspective, we can see that the character of the problem has, like John (12:8) says of the poor, always been with us.

Let us first go back to the Pleistocene, about a million years ago. This was a time of great change, with a succession of ice ages, and with the last one ending only about twenty thousand years ago. Each of these periods was accompanied by great change in the Australian landscape. In the north, sclerophyll forests alternated with rainforests, while in the south, the forests were alternately dominated by eucalypts and Casuarina. As sea levels fell, vast new savannahs were created, even as the retreat decimated the Great Barrier Reef, reducing it to tiny refugia clinging precariously to the edge of the continental slope. As sea levels rose, the Reef expanded across the continental shelf drowning those landscapes.

These are vast changes in land use, although they affected the use of the land by organisms other than man. And they are far more significant than changes that have occurred in the last few hundred years.

Now let us move forward in time to when man's footprint first appeared on the Australian landscape - about 40,000 years ago according to many scientists, and being steadily pushed further back by others. This also was a time of great change.

Some of it was climatic, as the continent gradually became drier, but there is also strong evidence of anthropogenic change as the new invader became the dominant species of the ecosystem and imposed his will upon it. We see evidence of the deliberate use of fire to alter the landscape on a grand scale all across the continent, and we see the ecosystem responding as fire-sensitive species were replaced by fire-tolerant ones. The grassland, eucalypt and acacia assemblages that seem so characteristic of much of the Australian landscape are now thought by some scientists to be the product of the key land use practice of the first peoples - routine burning of the landscape. Indeed we can see the wholesale replacement of plant communities, one by another, on a breathtaking scale which rivals (and probably exceeds) the changes wrought by later human invasions of this continent and the introduction of agriculture and pastoralism.

This first invasion, with its powerful landscape-altering technologies, also changed the animal communities dramatically. The first colonisation of the continent was also accompanied by the wholesale destruction of a unique marsupial megafauna which could not resist the advanced predation technologies of these early hunters. Whole families of large marsupials rapidly became extinct. It was the equivalent of the destruction of the African megafauna in our times, with the proviso that, in Africa, we may have averted the catastrophe in the nick of time.

In Australia, there has been no subsequent faunal or floral change that can compare to these changes that occurred over the last tens of thousands of years.

What does this perspective show us?

I think it shows us first that the hand of man lies heavily on the Australian landscape, and that man has been actively using the land for a very long time. The extent and the magnitude of these land use changes make a mockery of some of the more strident advocates of wilderness. If wilderness has something to do with escape from human influence, then there is no wilderness in Australia. The whole landscape, together with our animal and plant communities, has been altered by the hand of man since his first arrival on these shores.

It also shows us that land use changes with time and that every bit of Australia has had different land uses, both human and non-human, in the past and will certainly have different ones in the future.

Finally it shows us that land use has a context, and that context is the history of the Australian landscape. The use of some one bit of Australia cannot be considered in isolation from the use of the land nearby, nor from its use in the past. This creates problems for the more mystical rump of the conservation movement which seems to regard the biodiversity of a piece of land as some sort of indwelling property of the land which of itself justifies a conservation land use. Biodiversity is a dynamic, objectively measurable property of the Australian ecosystem, continually undergoing change as the system responds to its environment. At any one place, it will have been both higher and lower in the past, and will certainly fluctuate in the future.

Indeed, we may draw two conclusions from our historical perspective. The first, exemplified by my comments on wilderness, is that sequential land use has been a feature of Australia's history since man first populated the continent. Indeed, history is nothing more than shorthand here for sequential land use, and issues like wilderness cannot be understood without this context.

The second is exemplified by my comments on biodiversity: many land use issues, such as biodiversity, are naturally multiple land use issues, and their satisfactory resolution depends more on a mature understanding of their dynamics than the static sequestering of land under single use regimes. Indeed Australia has pioneered the two classic multiple land use regimes of modern times. Both, I am happy to say as a marine biologist, are in the oceans: the Great Barrier Reef Marine Park - which has as its motto 'ours to use wisely' - and the international Convention on the Conservation of Antarctic Marine Living Resources. Both of these regimes encourage multiple use of the system with an emphasis on the conservation of biodiversity.

... but it now has a modern spin

So far, I have concentrated on the physical aspect of land use. But what of the social setting? Land use decisions are social decisions, so what sort of context does this provide?

In Australia, at least, and probably in the rest of the developed world, land use is the front line of sustainable development. It is where sustainable development issues are made concrete and where they are fought out. Land use is where sustainable development gets real. Sustainable development is itself a difficult area. It is a democratic response to the often competing demands of economic development and environmental protection. The inherent nature of these issues, as recent history has shown, are such that we must expect that there will be strongly held and widely different views through the community on any particular land use issue.

More Swiss army knife than digging stick

We now have the physical and social context to be able to sketch out the specifications for integrated land use tools, or land use decision support systems in the modern jargon. And already we can see that these will be tools of some complexity, more Swiss army knife than digging stick. They need to be complex because the issues we wish to deal with are themselves complex. Now we can use blunt instruments on complex issues if all we wish to do is smash them up, but if we wish to dissect them, to understand them, then our instruments need to be commensurate in complexity with the issue.

In considering the blades that our Swiss army knife needs, I will draw on, for examples, the TRACS decision support system developed in our Bureau to assist in the analysis of land use issues.

Objective and subjective

Land use decisions are a mixture of the objective and subjective. There is a raft of objective information about the issue, such as information about the biophysical and socioeconomic structure and dynamics of the area and its neighbouring regions, that needs to represented, analysed and synthesised. There is also a great deal of subjective information about the issue, such as the beliefs, concerns, wishes and fears of the stakeholders, that also needs to be represented, analysed and synthesised. Our tool needs to be able to represent each of these objective and subjective aspects of the issue independently. It also needs to accommodate the common subjective desire to place different weights or emphases on the various different aspects of the issue, both objective and subjective: for example I might think that the biodiversity of an area is of much more importance than its mineral potential, while you may think that water reservation is more important than agricultural use. Such weighting, of course, needs to be visible to all concerned, because eventually one will need to defend those biases with some sort of argument rather than mere assertion. Figure 1, for example, shows a representation of objective information about weather, and Figure 2 shows a representation of subjectively weighted information about agricultural suitability.

Figure 1. Visualisation of objective spatial information

Figure 2. Visualisation of subjective spatial information

 

Quantitative and qualitative

Much of the information used by our tool will be in the form of quantitative measurements of one sort or another. These generally make scientists, engineers and the like very comfortable and happy. We like playing with numbers, and we have all spent many years not only learning how to do it, but also building number crunching toys, such as computers and other scientific instruments, to play with. But not all the aspects of land use issues can be represented by numbers, much is qualitative. By which I mean 'yes or no', 'it comes in several flavours', or 'this is better than that'.

These qualitative aspects of the issue are not embedded deep down in the guts of the problem where they can be ignored, but right at the top, starting with the key land use question: 'Should we do this or not?'. Indeed land use itself is a qualitative issue, so we cannot ignore the qualitative aspects of the problem. The naive response is to force these inherently qualitative data into a quantitative mould - to pretend they can be treated like numbers. I call this overweening need to appear scientific by being numeric 'naive quantifism'; and heroic but flawed attempts abound in the land use game. We need not force data so. There exist rigorous representational and analytical methods which provide qualitative analogues for most quantitative methods, allowing qualitative data and analyses to exist side by side with their quantitative counterparts. A fully quantitative representation of annual mean temperature is shown in Figure 3, Figure 4 shows a qualitative representation of land tenure.

Figure 3. Visualisation of quantitative information

 

Multidisciplinary and multidimensional
Land use issues are intrinsically multidisciplinary. Any analytical tool with land use pretensions must be reachable by all the different disciplines - geology, geography, demography, ecology, economics, hydrology and so on - and must provide a framework for their integration. The representation of the data from the different disciplines in a common geographical frame of reference - that is, where things exist in the landscape - is the most common way of ensuring this integration.

Figure 4. Visualisation of qualitative information

The multidimensional aspect is more contentious. It follows from the multidisciplinary nature of the issue that it is also multidimensional. The problem is how to analyse and synthesise such multidimensional data. One common way is to 'boil down' complex multidimensional data into simple one-dimensional indices. Such 'indicators' are common in economics and becoming fashionable in environmental areas. But what they gain in simplicity, they lose in fidelity to the underlying processes they purport to indicate. A better strategy is to maintain the multidimensionality of the data at all times, and to develop views of the data system which are tailored to the particular question at hand. Such syntheses maintain a path to the original data and provide, ultimately better understanding. Figure 5 shows the results of the integration of multidisciplinary, multidimensional data.

Figure 5. Visualisation of multidisciplinary, multidimensional information

 

Zoom in and zoom out

I argued above that context is important in understanding land use. We need to understand the proposed land use in the context of land uses nearby in space and in time. The capacity for our land use tool to zoom in and zoom out is thus of crucial importance. Figures 6 and 7 show the increasing information available as one zooms in on the set of Australian drainage data.

Figure 6. Visualisation of 'zoom out' information

 

Accessible by non-specialists as well as specialists

In a multidisciplinary world, we are all non-specialists: we have all been recast, in a sense, as the gifted amateurs of the 19th century. While I might understand the ecology, I must take the geology and economics on trust. When everyone can only verify, as it were, a small bit of the whole, it is of the utmost importance that individuals feel confident in accessing that whole. In our work, we have found that the most effective way to build this confidence and achieve this accessibility is through a visual paradigm. The use of effective visualisation cuts through disciplinary barriers quickly and allows levels of integration and synthesis not achievable in any other way.

Figure 7. Visualisation of 'zoom in' information

And finally, our Swiss army knife must allow the exploration of alternative futures, through the development of 'what if' scenarios. We must be able to replace actual objective data with possible objective data, and we must be able to replace one set of subjective views with another to explore what the world might be like.

'This will be the place for a village'

And so we come, like John Batman, to the crux of the matter: will this, after all, be the place for a village? We have arrived at a question which is ultimately, always, qualitative: Yes or no?

Our tools, if they are useful, will have sharpened up our understanding of the question. They may even have sharpened up the question itself. They will have conjured up the past by embedding the question in a proper context of the history of the Australian landscape. They will have even invoked the future through the exploration of different possible scenarios. They will have catalysed our thinking about multiple and sequential land use.

And our tools, if they are very good, will have made arriving at a decision much easier. But if they are excellent, these tools will not make the decision for us - because for that we need people.

Acknowledgments

I thank Simon Veitch, the developer of our TRACS decision support system, for helpful advice and enlightening figures.