Modelling Spatial Patterns of School Choice

A couple of weeks ago I visited King’s Department of Education to give a seminar I entitled Agent-based simulation for distance-based school allocation policy analysis. The aim was to introduce agent-based modelling to those unaware and hopefully open a debate on how it might be used in future education research. This all came about as I’ve been working on modelling the drivers and consequences of school choice with Profs Chris Hamnett and Tim Butler here in King’s Geography Department.

Hackney School Admissions Brochure

In their recent research, Chris and Tim looked at the role geography plays in educational inequalities in East London. Many UK local education authorities (LEAs) use spatial distance as a key criterion in their policy for allocating school places: people that live closer to a school rank get allocated to it before those that live farther away. This is necessary because it’s often the case that more people want to send their children to a school than there are places available at it. For example, you can read about the criteria the Hackney LEA uses in their brochure for 2012.

Using data from several LEAs, Chris and Tim showed empirically how this distance criterion is related to school popularity. School popularity is indicated for example by the ratio of school applicants to the number of places available at the school (A:P) – some schools have very high ratios (e.g. up to 8 applications per place) and others very low (e.g. down to around one application per place). Furthermore, this spatial allocation criterion is an important influence on parents’ strategies for school applications, dependent on the location of their home relative to schools and their ability to move home.

These allocation rules, combined with parent’s strategies, produce patterns and relationships between schools’ GCSE achievement levels, A:P ratio and the maximum distance that allocated pupils live from the school. In Barking, for example, we see in the figure below that more popular schools have higher percentages of pupils achieving five GCSE’s with grades A* – C, and that these same popular schools also have the smallest maximum distances (i.e. pupils generally live very close to the school).

Empirical Patterns in Barking Schools

This spatial pattern can also seen when we look at maps of the locations of successful and unsuccessful applicants to popular and less popular schools in Hackney. For example, looking at the figure below (found in Hamnett and Butler 2011) we can see how successful applicants to The Bridge Academy (a popular school) are more tightly clustered around the it than those for Clapton Girls’ Technology College (not such a popular school).

Map of successful and unsuccessful applicants to two schools in Hackney

The geography of this school allocation policy, combined with differences in parents’ circumstances, suggests this issue is a prime candidate for study using agent-based modelling. Agent-based simulation modelling might be useful here because it provides a means to represent interactions between individual actors with different attributes (in this case schools and parents) across space and time. Once the simulation model structure (e.g. rules of interactions between agents) has been established, it can then be used to examine the potential effects of things like opening or closing schools (i.e. changes in external conditions) or changes in school allocation policy rules or parents’ application strategies (i.e. internal model relationships and rules).

I developed an initial ‘model’ as a proof of concept and which you can try out yourself. Things have progressed from that proof of concept model, and the model now represents changes in cohorts of school applicants and pupils through time, including the potential for parents to move house to be more likely to get their child into a desired school.

In the seminar with the Department of Education guys I presented some ouput from the recent modelling. I showed how the abstract model with relatively few and simple assumptions can start from random conditions to reproduce empirical spatial patterns in school applications and attainment outcomes like those described above (see the figure below)

School model screenshot

I also presented early results from using the simulation model to explore implications of potential policy alternatives (such as closing failing schools). These ideas were generally welcomed in the seminar but there were some interesting questions about the what the model assumptions might entail for maintaining existing policy assumptions and intentions (what we might term the rhetoric of modelling).

I’m exploring some of these questions now, including for example issues of how we define a ‘good’ school and how parents’ school application strategies might change as allocation rules change. These will feed into a research manuscript that I’ll continue to work on with Chris and Tim.

Agent-based models – because they’re worth it?

So term is drawing to an end. There’s lots been going on since I last posted here and I’ll write a full update of that over the Christmas break. I’ll just highlight here quickly that the agent-based modelling book I contributed to has now been published.

Agent-Based Models of Geographical Systems, is editied by Alison Heppenstall, Andrew Crooks, Linda See and Mike Batty and presents a comprehensive collection of papers on the background, theory, technical issues and applications of agent-based modelling (ABM) in geographical systems. David O’Sullivan, George Perry, John Wainwright and I put together a paper entitled ‘Agent-based models – because they’re worth it?’ that falls into the ‘Principles and Concepts of Agent-Based Modelling’ section of the book. To give an idea of what the paper is about, here’s the opening paragraph:

“In this chapter we critically examine the usefulness of agent-based models (ABMs) in geography. Such an examination is important be-cause although ABMs offer some advantages when considered purely as faithful representations of their subject matter, agent-based approaches place much greater demands on computational resources, and on the model-builder in their requirements for explicit and well-grounded theories of the drivers of social, economic and cultural activity. Rather than assume that these features ensure that ABMs are self-evidently a good thing – an obviously superior representation in all cases – we take the contrary view, and attempt to identify the circumstances in which the additional effort that taking an agent-based approach requires can be justified. This justification is important as such models are also typically demanding of detailed data both for input parameters and evaluation and so raise other questions about their position within a broader research agenda.”

In the paper we ask:

  • Are modellers agent-based because they should be or because they can be?
  • What are agents? And what do they do?
  • So when do agents make a difference?

To summarise our response to this last question we argue;

“Where agents’ preferences and (spatial) situations differ widely, and where agents’ decisions substantially alter the decision-making con-texts for other agents, there is likely to be a good case for exploring the usefulness of an agent-based approach. This argument focuses attention on three model features: heterogeneity of the decision-making context of agents, the importance of interaction effects, and the overall size and organization of the system.”

Hopefully people will find this, and the rest of the book useful! You can check out the full table of contents here.

Citation
O’Sullivan, D., J.D.A. Millington, G.L.W. Perry, J. Wainwright (2012) Agent-based models – because they’re worth it? p.109 – 123 In: Heppenstall, A.J., A.T. Crooks, L.M. See, M. Batty (Eds.) Agent-Based Models of Geographical Systems, Springer. DOI: 10.1007/978-90-481-8927-4_6

Philosophy of Modelling and RGS 2011

I just updated the Philosophy of Modelling page on my website. It’s not anything too detailed but I was prompted to add something by my activities over the last few weeks. I’ve been working on both making progress with my ‘modelling narratives’ project and a paper I’ve started working on with John Wainwright exploring the epistemological roles agent-based simulation might play beyond mathematical and statistical modelling (expected to appear in the new-ish journal Dialogues in Human Geography).

It’s only a few weeks now until this year’s Royal Geographical Society annual meeting (31 Aug – 2 Sept). I’m making two presentations, unfortunately both in the same session! It seems my work sits squarely within ‘Environmental modelling and decision making’, as the both abstract I submitted were allocated to that session on the Friday afternoon (Skempton Building, Room 060b; last session of the week so people might be flagging!). The first presentation will deal with the ‘generative’ properties of agent-based modelling [.pdf] and what that implies for how we might study and use that modelling approach, and the second will summarise the Michigan forest modelling work we’ve completed so far. Both abstracts are below.

This also seems a good point to highlight that King’s Geography Department are hosting a drinks reception on the Thurdsay evening from 18:45 at Eastside Bar, Princes Garden, SW7 1AZ. Free drinks for the first 50 guests, so get there sharpish!

Millington RGS 2011 Abstracts

Model Histories: The generative properties of agent-based modelling
Fri 2 Sept, Session 4, Skempton Building, Room 060b
James Millington (King’s College London)
David O’Sullivan (University of Auckland, New Zealand)
George Perry (University of Auckland, New Zealand)

Novels, Kundera has suggested, are a means to explore unrealised possibilities and potential futures, to ask questions and investigate scenarios, starting from the present state of the world as we observe it – the “trap the world has become”. In this paper, we argue that agent-based simulation models (ABMs) are much like Kundera’s view of novels, having generative properties that provide a means to explore alternative possible futures (or pasts) by allowing the user to investigate the likely results of causal mechanisms given pre-existing structures and in different conditions. Despite the great uptake in the application of ABMs, many have not taken full advantage of the representational and explanatory opportunities inherent in ABMs. Many applications have relied too much on ‘statistical portraits’ of aggregated system properties at the expense of more detailed stories about individual agent context and particular pathways from initial to final conditions (via heterogeneous agent interactions). We suggest that this generative modelling approach allows the production of narratives that can be used to i) demonstrate and illustrate the significance of the mechanisms underlying emergent patterns, ii) inspire users to reflect more deeply on modelled system properties and potential futures, and iii) provide a means to reveal the model building process and the routes to discovery that lie therein. We discuss these issues in the context of, and using examples from, the increasing number of studies using ABMs to investigate human-environment interactions in geography and the environmental sciences.

Trees, Birds and Timber: Coordinating Long-term Forest Management
Fri 2 Sept, Session 4, Skempton Building, Room 060b
James Millington (King’s College London)
Megan Matonis (Colorado State University, United States)
Michael Walters (Michigan State University, United States)
Kimberly Hall (The Nature Conservancy, United States)
Edward Laurent (American Bird Conservancy, United States)
Jianguo Liu (Michigan State University, United States)

Forest structure is an important determinant of habitat use by songbirds, including species of conservation concern. In this paper, we investigate the combined long-term impacts of variable tree regeneration and timber management on stand structure, bird occupancy probabilities, and timber production in the northern hardwood forests of Michigan’s Upper Peninsula. We develop species-specific relationships between bird occupancy and forest stand structure from field data. We integrate these bird-forest structure relationships with a forest model that couples a forest-gap tree regeneration submodel developed from our field data with the US Forest Service Forest Vegetation Simulator (Ontario variant). When simulated over a century, we find that higher tree regeneration densities ensure conditions allowing larger harvests of merchantable timber, and reducing the impacts of timber harvest on bird forest-stand occupancy probability. When regeneration is poor (e.g., 25% or less of trees succeed in regenerating), timber harvest prescriptions have a greater relative influence on bird species occupancy probabilities than on the volume of merchantable timber harvested. Our results imply that forest and wildlife managers need to work together to ensure tree regeneration and prevent detrimental impacts on timber output and habitat for avian species over the long-term. Where tree regeneration is currently poor (e.g., due to deer herbivory), forest and wildlife managers should pay particularly close attention to the long-term impacts of timber harvest prescriptions on bird species.

Summer 2011 Papers

Since I last posted, THREE of the papers I’ve mentioned here previously have become available online! Here are their details, abstracts are below. Email me if you can’t get hold of them yourself.

Millington, J.D.A., Walters, M.B., Matonis, M.S., Laurent, E.J., Hall, K.R. and Liu, J. (2011) Combined long-term effects of variable tree regeneration and timber management on forest songbirds and timber production Forest Ecology and Management 262 718-729 doi: 10.1016/j.foreco.2011.05.002

Millington, J.D.A. and Perry, G.L.W. (2011) Multi-model inference in biogeography Geography Compass 5(7) 448-530 doi: 10.1111/j.1749-8198.2011.00433.x

Millington, J.D.A., Demeritt, D. and Romero-Calcerrada, R. (2011) Participatory evaluation of agent-based land use models Journal of Land Use Science 6(2-3) 195-210 doi:10.1080/1747423X.2011.558595

Millington, J.D.A. et al. (2011) Combined long-term effects of variable tree regeneration and timber management on forest songbirds and timber production Forest Ecology and Management 262 718-729
Abstract
The structure of forest stands is an important determinant of habitat use by songbirds, including species of conservation concern. In this paper, we investigate the combined long-term impacts of variable tree regeneration and timber management on stand structure, songbird occupancy probabilities, and timber production in northern hardwood forests. We develop species-specific relationships between bird species occupancy and forest stand structure for canopy-dependent black-throated green warbler (Dendroica virens), eastern wood-pewee (Contopus virens), least flycatcher (Empidonax minimus) and rose-breasted grosbeak (Pheucticus ludovicianus) from field data collected in northern hardwood forests of Michigan’s Upper Peninsula. We integrate these bird-forest structure relationships with a forest simulation model that couples a forest-gap tree regeneration submodel developed from our field data with the US Forest Service Forest Vegetation Simulator (Ontario variant). Our bird occupancy models are better than null models for all species, and indicate species-specific responses to management-related forest structure variables. When simulated over a century, higher overall tree regeneration densities and greater proportions of commercially high value, deer browse-preferred, canopy tree Acer saccharum (sugar maple) than low-value, browse-avoided subcanopy tree Ostrya virginiana (ironwood) ensure conditions allowing larger harvests of merchantable timber and had greater impacts on bird occupancy probability change. Compared to full regeneration, no regeneration over 100 years reduces merchantable timber volumes by up to 25% and drives differences in bird occupancy probability change of up to 30%. We also find that harvest prescriptions can be tailored to affect both timber removal volumes and bird occupancy probability simultaneously, but only when regeneration is adequate. When regeneration is poor (e.g., 25% or less of trees succeed in regenerating), timber harvest prescriptions have a greater relative influence on bird species occupancy probabilities than on the volume of merchantable timber harvested. However, regeneration density and composition, particularly the density of Acer saccharum regenerating, have the greatest long-term effects on canopy bird occupancy probability. Our results imply that forest and wildlife managers need to work together to ensure tree regeneration density and composition are adequate for both timber production and the maintenance of habitat for avian species over the long-term. Where tree regeneration is currently poor (e.g., due to deer herbivory), forest and wildlife managers should pay particularly close attention to the long-term impacts of timber harvest prescriptions on bird species.

Millington, J.D.A. and Perry, G.L.W. (2011) Multi-model inference in biogeography Geography Compass 5(7) 448-530
Abstract
Multi-model inference (MMI) aims to contribute to the production of scientific knowledge by simultaneously comparing the evidence data provide for multiple hypotheses, each represented as a model. With roots in the method of ‘multiple working hypotheses’, MMI techniques have been advocated as an alternative to null-hypothesis significance testing. In this paper, we review two complementary MMI techniques – model selection and model averaging – and highlight examples of their use by biogeographers. Model selection provides a means to simultaneously compare multiple models to evaluate how well each is supported by data, and potentially to identify the best supported model(s). When model selection indicates no clear ‘best’ model, model averaging is useful to account for parameter uncertainty. Both techniques can be implemented in information-theoretic and Bayesian frameworks and we outline the debate about interpretations of the different approaches. We summarise recommendations for avoiding philosophical and methodological pitfalls, and suggest when each technique is best used. We advocate a pragmatic approach to MMI, one that emphasises the ‘thoughtful, science-based, a priori’ modelling that others have argued is vital to ensure valid scientific inference.

Millington et al. (2011) Participatory evaluation of agent-based land use models Journal of Land Use Science 6(2-3) 195-210
Abstract
A key issue facing contemporary agent-based land-use models (ABLUMs) is model evaluation. In this article, we outline some of the epistemological problems facing the evaluation of ABLUMs, including the definition of boundaries for modelling open systems. In light of these issues and given the characteristics of ABLUMs, participatory model evaluation by local stakeholders may be a preferable avenue to pursue. We present a case study of participatory model evaluation for an agent-based model designed to examine the impacts of land-use/cover change on wildfire regimes for a region of Spain. Although model output was endorsed by interviewees as credible, several alterations to model structure were suggested. Of broader interest, we found that some interviewees conflated model structure with scenario boundary conditions. If an interactive participatory modelling approach is not possible, an emphasis on ensuring that stakeholders understand the distinction between model structure and scenario boundary conditions will be particularly important.

Changing the ‘Targets and Timetables’ Climate Change Narrative

Earlier this week I was in Leipzig, Germany, to meet the Ecological Modelling research group at the Helmholz Centre for Environmental Research (UFZ) and one of my PhD supervisors, Dr. George Perry. While there I was lucky to meet and talk with some renowned ecological modellers: Thorsten Wiegand, who’s work includes spatial point process modelling (although some of his discussion with George about that was a bit technical for me!); Volker Grimm, proponent the ‘Pattern-Oriented Modelling’ approach (look out for a new review of this in Phil Trans. of the Royal Society in the near future), and Andreas Huth, notable forest dynamics modeller.

At UFZ I gave a presentation I entitled “Future Forests: Managing and Creating Forests for Biodiversity, Recreation, Timber and Carbon” in which I talked about some of the work I did in Michigan and the new project I’m working on now in the UK. The talk seemed to go down well and the research group had some very good questions, both about technical aspects of the modelling and the issues it is applied to (i.e. forest ecosystem management and woodland creation, including the Woodland Carbon Code). Thanks to Juergen Groeneveld for organising this (and his hospitality at UFZ).

Much of the data I presented regarding the Michigan work was collected by Megan Matonis. Her analyses of that data, on which I helped and supervised, are now available to read in a paper that is currently in press with Forest Ecology and Management (email me if you can’t access the online version).

Another interesting activity at UFZ was hearing Roger Pielke Jr. talk about the need to ‘change the climate change narrative’. In his talk he suggested that understanding all carbon policy can be boiled down to a single sentence;

‘people engage in economic activity that uses energy from carbon emitting generation’.

He emphasised that he thinks the “Targets and Timetables” approach to reducing anthropogenic carbon emissions is flawed. As an example, he used the case of the UK and the Climate Change Act of 2008 which set the aim of an 80% cut in the country’s carbon emissions by 2050 compared to 1990 levels, with an intermediate target of 34% by 2020. However, Pielke argues that given the ‘iron’ law of climate policy (that we cannot mitigate emissions by reducing GDP, both because people will pay only so much to mitigation now, and because increasing GDP is seen as a virtue by way of its effects on povety reduction) we cannot hit these types of targets.

Previous decarbonisation of the UK economy has been achieved by replacing the contribution to GDP from high-emitting manufacturing with low-emitting financial services. He wonders how long can this go and presented his estimate that for the UK to actually hit its 2020 target it will have to build more than 40 nuclear power stations in the next 10 years. In this context, he suggested that the building of a third runway at Heathrow was an insignificant concern (in terms of the new emissions it would generate) when there are still 1.5 billion people globally who do not have access to electricity. His argument is that we do not know how to achieve the targets and the timetables we have set ourselves.

Pielke argues that we must change the climate change narrative from

“We need to use less energy and fossil fuels are cheap

to

“We need more energy and fossil fuels are too expensive“.

This would allow these 1.5 billion people to access the electricity they aspire to whilst driving the growth of alternative, cleaner, sources of energy. I like this argument – and his one about making small steps towards these change to reach bigger changes – but it seems to run counter to his point about the insignificance of another runway at Heathrow (which by increasing capacity for flights would continue the narrative of cheap fossil-fuelled energy). Opening a third runway but only allowing non-fossil-fuelled aeroplanes to use it is ultimately most consistent with the change in narrative he argues for.

And of course, while at UFZ, George Perry and I took the opportunity to discuss past, current and ongoing work over beers and dinner. Mainly we discussed the idea surrounding the narrative properties of generative simulation models and on which I plan to submit a manuscript to a journal for publication soon. But we also thought about other areas of research including land use modelling (continuing our work in Spain) and landscape disturbance-succession modeling (including the use of the LFSM I’ve developed with paleo-estimates of wildfire regimes).

All-in-all a very interesting and productive trip!

The Politics of Expectations

Next year’s Annual meeting of the Association of American Geographers will be in Seattle. I was considering attending but I think it might be best to let the dust settle after moving back to the UK in January. Many others will be there however, including James Porter, a colleague and friend from PhD times at King’s College, London. On his behalf, here’s the call for papers for a session he’s organising at the meeting. Deadline is 1st October, more details at the bottom.

Call for Papers
The Politics of Expectations: Nature, Culture, and the Production of Space

Association of American Geographers, Annual Meeting, 12-16th April 2011, Seattle.

Session Organisers:
James Porter (King’s College London) and Samuel Randalls (University College London)

Expectations are incredibly powerful things. Whether materialized via climatic models, economic forecasts, or based on the promise of personalised medicines, expectations (and those who engineer them) play a deeply political yet often unsung role in bringing into being a particular kind of future as well as shaping a particular kind of present. Savvy actors seeking to engineer change may decide to write editorials, give press briefings, or try to normalise trust between the communities involved so as to enrol support and resources for an emerging marketplace (and consumer) they have envisioned. Such discursive as well as performative practices pre-emptively shape the social and economic context for developing technologies so that the actors involved not only develop their physical objects but also influence other people’s thinking. Rather than dismiss such efforts as exaggerated or self-serving claims, the “sociology of expectations” (cf. Brown, 2003; Hedgecoe, 2004; Law, 1994) points to the constructive, performative, and even destructive role such expectations have in today’s world where competition for funding, research impact and innovation are so intense. As many geographers researching the ‘commercialization of nature’ have noted (cf. Castree, 2003; Johnson, 2010; Lave et al., 2010; Prudham, 2005), expectations of future natures inhabit contemporary environmental management in a series of subtle and not so subtle ways for all actors.

But how are expectations created, configured, and stabilized? What, and whose, interests shape them, and in turn, whose interests do they shape? And why do some persist whilst others don’t? Such questions speak directly to the ways in which nature (and knowledge of it) is being increasingly commercialized and commodified through its interactions with science and technology. This session builds on controversies such as the climate change emails at UEA, medical trials, carbon forestry and much more to showcase how the “future” is mobilized to govern or proliferate uncertainty and justify particular mechanisms for managing environmental problems. Geographers are uniquely placed to comment on this providing theoretical depth and empirical evidence that sheds light on the commodification of nature whilst also contributing to the socio-technical analyses employed by science and technology studies scholars. We therefore invite papers addressing (though not limited to) the following questions:

  • Who constructs expectations and why? How / where do they get enacted (i.e. technological, sociocultural, artefacts, etc.)? And how do they get accepted, institutionalized, or perhaps resisted?
  • How are expectations of nature commercialized? To what extent are expectations central to processes of commercialization and does this vary depending on the specific environmental arena? Are there unnatural expectations?
  • Do expectations have agency? Can they be negotiated or adapted? If so, what role have geographers played in shaping past perceptions and might hope to play in the future?
  • What happens if a set of expectations is not successful? Why didn’t they succeed? And what lessons can we learn?

Abstracts should be sent to both James Porter (james.porter at kcl.ac.uk) and Samuel Randalls (s.randalls at ucl.ac.uk) by Friday 1st October 2010.

For conference information, see: www.aag.org/cs/annualmeeting

Leverhulme Early Career Fellowship

Around the time I wrote this blog about the National Assessment of UK Forestry and Climate Change Steering Group report I was thinking about writing a proposal to the Leverhulme Trust for an Early Career Fellowship. I found out recently that my proposal was successful and so from January 2011 I will be back at King’s College, London!

The Leverhulme Trust makes awards in support of research and education with special emphasis on original and significant research that aims to remove barriers between traditional disciplines. Their Early Career Fellowships are awarded across all disciplines and in 2010 approximately 70 were expected to be awarded to individuals to hold at universities in the UK. Given the emphasis on original, significant and cross-disciplinary research made by the Trust I looked for something that matched my research skills in coupled human and natural systems modelling but that pushed work in that area in a new direction. I thought back to the ideas about model narratives I have previously explored with David O’Sullivan and George Perry (but have not worked on since then) and Bill Cronon’s plenary address at the Royal Geographical Society in 2006 on the need for ‘sustainable narratives’. With that in mind, and given the UK Forestry and Climate change report I had been reading, I decided to make a pitch for a project that would explore how narratives from the use of models could help individuals identify how local actions transcend scales to mitigate global climate change in the context of the anticipated woodland planting that will be ongoing in the UK in future years. It proved to be a successful pitch!

I’m sure I will blog plenty more about the project in the future, so for now I will just leave you with the proposal rationale (below). I’m looking forward to getting to work on this when I get back to London, but before that there’s plenty more things to get done on the Michigan forest landscape ecological-economic modelling.

Model narratives for climate change mitigation
The abstract, vast, and systemic narratives that dominate the issue of global climate change do little to illustrate to individuals and groups how their actions might contribute to mitigate the effects of what is often framed as a global problem (Cronon 2006). Ways to improve the ability of individuals and groups to identify how their local actions transcend scales to mitigate global climate change are needed. In this research I will explore how narratives produced from computer simulation models that represent individuals’ actions can provide people with insights into how their behaviour affects system properties at a larger scale. Although the narrative properties of simulation models have been highlighted (O’Sullivan 2004), the use of models to develop localised narratives of climate change which emphasise individual agency has yet to be explored. Confronting individuals with these narratives will also help researchers reveal important underlying, and possibly implicitly held, assumptions that influence choices and behaviour.

This research will address the following general questions:

  • How can computer simulation models be better used to reveal to individuals how their local actions can contribute to global environmental issues such as Climate Change Mitigation (CCM)?
  • What are the narrative properties of simulation models and how can they be exploited to help individuals find meaning about their actions as they relate to global climate change?
  • By using simulation tools to spur reflection what can we learn about the factors influencing individuals’ choices and behaviour with regards CCM options?

Answering these questions will require a uniquely interdisciplinary research approach that spans the physical sciences, social sciences and humanities. Such ground-breaking, boundary-crossing work is necessary if we are to re-connect the physical sciences with the publics they intend to benefit and find solutions to large-scale and pressing environmental problems. For example, one of the key findings from a recent report by the National Assessment of UK Forestry and Climate Change Steering Group (Read et al. 2009) was that “[t]he extent to which the potential for additional [greenhouse gas] emissions abatement through tree planting is realized … will be determined in large part by economic forces and society’s attitudes rather than by scientific and technical issues alone” (p.xvii). The report also argued the need “to better understand and consider the role of different influences affecting choices and behaviour. Without the appropriate emotional, cultural or psychological disposition, information will make no difference.” (p.210). Narratives based on scientific understanding which portray how individuals can make a difference to large-scale, diffuse environmental issues will be important for fostering such a disposition. Simulation models – quantitative representations of reality which provide a means to logically examine how high-level and large-scale patterns are generated by lower-level and smaller-scale processes and events – have the potential to contribute to the construction of these narratives.

US-IALE 2010 Notes

The 25th US-IALE annual meeting I attended in Athens, Georgia, a couple of weeks ago was notable for the presence of so many important figures in the field of landscape ecology. Several gave interesting plenary talks and the Presidents Symposium had presentations by many of the previous US-IALE Presidents and past editors of the journal Landscape Ecology. I also attended interesting presentations and discussion in the wildfire symposium and elsewhere.

Plenary Presentations
In the introductory plenary Profs. Richard Forman, Gary Barrett and Monica Turner gave their views on the origins and state of the field. Forman described his PhD work, rooted in the theory of island biogeography, in a Pine barrens landscape. He told how he suddenly realised he had been ignoring the context of his ‘islands’ and decided to look at how he might consider his study area as a landscape of patches arranged in a mosaic. He also talked about the ‘ecumenicalism of landscape ecology’ and how it is an important field for the development of interdisciplinary human-environment research.

Barrett spoke about the importance of the Allerton Park meeting in 1983 and the relationship of landscape ecology to the LTER network. He highlighted that landscape ecology is a ‘meeting point of [ecological] theory and application’ and the creation of the journal Ecological Applications (but also noted the creation 27 years earlier of the Journal of Applied Ecology).

Turner, the organiser of the very first US-IALE meeting, pointed out how similar current research themes are to those of 25 years ago. Questions still of relevance to landscape ecology include those about the relative importance of different drivers of ecological patterns and the importance of heterogeneity for driving ecosystem processes and species interactions.

Of the other plenary presentations, I found Joe Tainter’s presentation very interesting. His ‘big’ talk discussed the rise and fall of civilisations from the perspective of social and cultural complexity and Energy Return On Energy Investment (EROEI). He highlighted that sustaining complex societies requires a high EROEI and used the Roman and Byzantine Empires as examples to illustrate this. He stressed that sustainability is an active condition of problem solving – the capacity for which must itself be sustained – and questioned whether renewable energy resources (such as solar and wind power) have sufficient EROEI to allow us to do that in the future.

Presidents Symposium
In the Presidents Symposium, Jianguo Wu provided a pluralistic and hierarchical perspective of landscape ecology. Wu argued that the goal of landscape ecology should not just be about reporting on landscapes but about changing them. He also argued that the human landscape is the ‘most operational spatial scale for sustainability science’. He highlighted the formation of two new sections in the landscape ecology journal; ‘Landscape Ecology in Review’ and ‘Landscape Ecology in Practice’.

These issues were taken up later in the same session by Paul Opdam who discussed the transfer of pattern-process knowledge to society (as he wrote about with Joan Iverson Nassauer). He argued that there are three ways to do this; i) by asking questions about how our scientific knowledge is used in practice by planners, managers and stakeholders, ii) developing methods by testing them in practice, and iii) co-producing knowledge with non-scientists. He also argue that practical application of knowledge is the key methods for the ‘learning scientist’ and that research along these lines would be welcomed in the Landscape Ecology in Practice section of the journal.

Wildfire Symposium
The wildfires session contained some familiar faces. Rachel Loehman and Maureen Kennedy presented progress on their wildfire-related models and Don McKenzie outlined his efforts to take much of the recent work towards a coherent ‘theory of landscape fire’. The key elements to this theory he suggested would be energy, regulation (management) and scaling. In particular he emphasizes that we need to work hard on understanding the importance of landscape memory and the legacy of previous wildfire events on future ones.

Particularly encouraging to see was the work by Paul Hessburg and Nick Povak on self-organization and wildfire scaling in California (using data for 1950-2007). They argued that broken-stick regression is needed to represented their wildfire frequency-area data, as scale free power-law behaviour is only present across about two orders of magnitude in the medium size fires. At the lower end of the frequency-area distribution (smaller, frequent fires) they suggested bottom-up controls on the wildfire regime due to insects, stand dynamics and topography, and at the upper end of the frequency-area distribution (larger, infrequent fires) they suggested top-down controls on the wildfire regime due to climate and geology. This work examining the drivers of different wildfire regime scaling statistics certainly seems to be the way to go.

Other Discussions
My presentation seemed to go down well and I got some interesting questions. Frederik Doyon of Université du Québec en Outaouai was particularly interested in our work in the mixed hardwood-conifer forests of Michigan. Also in my session, Maria Santos presented her work comparing culture and ecology between the Mediterranean oak woodland landscapes of Portugal and California. We discussed some of the links between her work and my PhD research.

All round it was a good meeting with some interesting discussions in the various plenary session, symposia and in the pub. Here’s to another 25 years of US-IALE.

US-IALE 2010 Preparation

Next week is the Twenty-fifth Anniversary Symposium of the US chapter of the International Association of Landscape Ecology (US-IALE). I’ll be in attendance in Athens, Georgia and am currently working on my presentation, entitled Ecological-economic modeling for sustainable forest management (scheduled for Thursday 8th, 2.20pm in room T/U). In the context of our larger modelling project I’ll present work we’ve published, stuff we’re still working on, and the initial results from putting it all together.

Several symposia have been organised and I plan to be at those that consider landscape ecology and wildfires, bioenergy and land-use change, and climate change and landscape connectivity. Particularly interesting should be Don McKenzie’s presentations on ecosystem energetics and scaling laws in the wildfire symposium and Paul Opdam’s presentations on Natura 2000 and the role of landscape ecology in the climate change symposium. Two of the plenary addresses I’d like to catch are Collapse and Sustainability: Lessons from History (Joseph A Tainter) and Linking Renaissance Ecologists with Citizen Scientists to Advanced Scientific Research and Literacy (Carol Brewer).

As usual CSIS has a strong presence at US-IALE this year with seven presentations, including the insights of Jack Liu and Wu Yang into the challenges and opportunities for landscape ecology and conservation in coupled human natural research, the analysis by Andres Vina and Xiaodong Chen of the potential conservation benefits that might be offset by natural disasters, Mao-Ning Tuanmu’s work on Giant Panda habitat and the work by Pete Esselman and Dana Infante on the National Assessment of the Status of Fish Habitat. The full list of CSIS presentations is below.

It’s shaping up to be a good couple of days! I’ll try to tweet and blog some thoughts as they arise during the conference and maybe reflect on things afterwards also.

CSIS Presentations at US-IALE 2010
6th April
Are conservation benefits offset by natural disasters? — The case of the May 12, 2008 Wenchuan Earthquake. Andrés Viña, Xiaodong Chen, Wei Liu, et al.

Coupling human and natural systems: Challenges and opportunities for landscape ecologists. Jianguo Liu

The spatial framework and results of the initial National Assessment of the Status of Fish Habitat. Peter C Esselman, Dana M Infante, et al.

7th April
Effects of human-environment relationships on the spatiotemporal dynamics of giant panda habitat. Mao-Ning Tuanmu, Wei Liu, Andrés Viña, et al.

8th April
Ecological-economic modeling for sustainable forest management. James D A Millington, Michael B Walters, Megan S Matonis, et al.

Mechanisms for effective conservation in coupled human-natural systems. Wu Yang, Wei Liu, Mao-Ning Tuanmu, et al.

Patterns and drivers of reforestation: A case study in the Qinling Mountains, China. Yu Li, Andrés Viña, Jianguo Liu

‘Mind, the Gap’ paper in press

I hoped it would be quicker than previous papers, but the review process of the ‘Mind, the Gap’ manuscript I worked on with John Wainwright hasn’t been particularly fast. I guess that’s just how it goes with special issues. I’ll discuss some of the topics we touch on in the paper in a future post. For now here’s the abstract – look out for the full paper on the ESPL website in the next couple of months.

Mind, the Gap in Landscape-Evolution Modelling
John Wainwright and James Millington
Earth Surface Processes and Landforms (Forthcoming)

Abstract
Despite an increasing recognition that human activity is currently the dominant force modifying geomorphic landscapes, and that this activity has been increasing through the Holocene, there has been little integrative work to evaluate human interactions with geomorphic processes. We argue that agent-based models (ABMs) are a useful tool for overcoming the limitations of existing, highly empirical approaches. In particular, they allow the integration of decision-making into process-based models and provide a heuristic way of evaluating the compatibility of knowledge gained from a wide range of sources, both within and outwith the discipline of geomorphology. The application of ABMs to geomorphology is demonstrated from two different perspectives. The SPASIMv1 (Special Protection Area SIMulator version 1) model is used to evaluate the potential impacts of land-use change – particularly in relation to wildfire and subsequent soil conditions – over a decadal timescale from the present day to the mid-21st century. It focuses on the representation of farmers with traditional versus commercial perspectives in central Spain, and highlights the importance of land-tenure structure and historical contingencies of individuals’ decision making. CYBEROSION, on the other hand, considers changes in erosion and deposition over the scale of at least centuries. It represents both wild and domesticated animals and humans as model agents, and investigates the interactions of them in the context of early agriculturalists in southern France in a prehistoric context. We evaluate the advantages and disadvantages of the ABM approach, and consider some of the major challenges. These challenges include potential process scale mis-matches, differences in perspective between investigators from different disciplines, and issues regarding model evaluation, analysis and interpretation. If the challenges can be overcome, this fully-integrated approach will provide geomorphology a means to conceptualize soundly the study of human-landscape interactions.