FOOD SECURITY: PERSPECTIVES OVER THE LAST 40 YEARS

Food security has undergone many changes since it came to global attention in the early 20^th century. The changes in definition have been numerous and have worked as a means to track and formalise the shifting perceptions around the issue. Food security has been perennial in the global south (specifically Asia, Latin America and Sub-Saharan Africa) and aid and trade histories have defined this socio-economic and climatic issues with political instability, poverty, institutional weakness as well as natural hazards playing a large role in shaping this field (Devereux and Maxwell 2001).

Food security has been defined in dozens of ways (more than 30 definitions are given in Maxwell 1996) with interest waxing and waning over time (Devereux and Maxwell 2001). Importantly three major paradigm shifts can be recognized throughout the last 40 years of food security thought (Maxwell 1996). The shifts in perspective on food security can be tracked as a move from a supply based approach at a global level to one focused on over-all development and a household and individual based approach. The paradigm shifts have been outlined and reviewed in-depth by Maxwell (1996) and can be defined as follows: (1) From the global and national to the household and the individual; (2) From a food perspective to a livelihood perspective; (3) From objective indicators to subjective perception. Each of these paradigm shifts occur around social, political and economic responses to the changing food system and solving the problem of food insecurity. This essay aims to highlight some of the developments that influenced the change in perspective moving from the 1970’s and culminating in our present understanding of food security.

The 1970’s began with a food crisis that highlighted the fragility of world food security (Shaw 2007), after decades of surplus production in the West (Borlaug 2000). The 1960’s ended with the disappointment and failure of the Green Revolution in Asia (Shaw 2007). The Green revolution, which started in the mid-1940’s in Asia, was expected to solve the world food security problem through technological innovations such as high yield cereals and grains, pesticides and fertilizers (Brown 1970). But 15 years after its beginnings in Mexico the Green Revolution failed to solve the global food security problem and despite food stocks almost doubling since the beginning of the revolution, food insecurity was still widespread (Borlaug 2000). The realisation of the failure of the Green Revolution came alongside two unusually large monsoon seasons in Asia (Shaw 2007) as well as crop failure in the USSR (UN 1975) which put pressure on international food aid. The 1970’s therefore began with a food crisis which led to the World Food Conference (WFC) in 1974 (United Nations 1975).

Prior to the 1974 World Food Conference, food security perspectives centred on supply and demand of food stocks premised on the Malthusian idea that a time would come when human consumption, as a result of population growth, would outstrip food production. The crisis of the early 1970’s seemed to highlight this perception with food aid increasing to fill the gap in production. The UN thus defined food security as the

Availability at all times of adequate world supplies of basic food-stuffs… to sustain a steady expansion of food consumption… and to offset fluctuations in production and prices (UN 1975).

This definition and the preceding crisis resulted in heavy subsidisation to the extent that “cropping patterns were distorted, domestic trade was repressed and consumer preferences were altered” (Stevens et al. 2003: 1). It appears as though these issues did not align with common perspective and governments continued, and many still do, to focus on national food sufficiency through a dependence on international aid and import (Harsch 1992). In addition to this unsustainable aid, it became clear that food insecurity could occur simultaneously with food surplus and it occurred to Sen (1981) that Malthus’s well known and pessimistic theory could be entirely incorrect.

Sen (1981) introduced the individual to the problem of food security with his theory of entitlements which makes the point that we do not live in a society in which food is equally distributed but one in which the amount of food a person has access to depends on what he owns and what he can get for what he owns through trade and production. This idea, commonplace in nutrition planning but ill-defined as a concept in food security (Devereux 1993), cemented the shift in perspective from a global issue of supply and demand to the household problem incorporating access and entitlement (Devereux and Maxwell 2001). Sen’s approach showed that famine, and hence cases of food insecurity, was not only dependent on food production but on sudden drops in the purchasing power of specific social groups and additionally that degrees of food security could exist in a single country (Shaw 2007).

The entitlements approach and its emphasis on the individual made a formal impact on the definition of food security through definitions stated by the Food and Agriculture Organisation (FAO 1983) and the World Bank (1986). Both definitions included the distinction of ensuring food security of people, as opposed to the general call for adequacy of food supplies stated in the 1975 definition. Thus food security became a more complex problem that included the highly contextual aspect of entitlements and individuals (Maxwell and Smith 1992). This essentially defines the conclusion of the first paradigm shift outlined by Maxwell (1996).

The entitlement approach, although revolutionary, was not without criticism. Maxwell and Smith (1992) and Swift (1989) outline some of the main criticisms of Sen’s analysis. Of importance is the household level analysis of the approach which ignores any uneven intra-household distribution of food. Additionally Sen assumes that inadequate food leads to death which ignores the importance of disease and famine related mortalities. The approach does not easily incorporate some important social systems such as social capital and social networks which play a role in understanding the complex structures which led to the next paradigm shift (Swift and Hamilton 2001).

The second shift occurred alongside the tremendous growth in urban areas and an acknowledgment of the complexity surrounding urban and rural livelihoods (Ruel et al. 1998). The food first approach of the entitlements theory, although broader and more complex than the supply approach, did not encompass much of the complexity surrounding the decisions and trade-offs between procuring food, maintaining assets and upholding social standings and life style (de Waal 1989). Through studying famine in Darfur, Sudan, de Waal (1991) found that people were willing to go hungry in order to avoid future hunger. It became apparent that households in both rural and urban settings may have multiple objectives beyond maintaining food security (Swift and Hamilton 2001).

The food first approach was largely premised on Maslow’s theory on the hierarchy of needs whereby food is assigned the utmost importance as a lower-order need fundamental to the organisation and maintenance of social life (Hopkins 1986). However the second paradigm shift in perspectives of food security recognised that this hierarchy of needs was not necessarily so simple and the framework of livelihoods, and especially sustainable livelihoods, offered a far more useful context in which to address the problems of food security (Swift and Hamilton 2001). This new framework includes the concept of security and a wider scope of risk avoidance than seen in the previous 20 years of food security analysis (Maxwell and Smith 1992). The concept of risk allowed for the inclusion of a future analysis of food security and the critical choices which needed to be made by policy planners as well as the rural poor in search of “entitlement protection” (Dreze and Sen 1991).

Combining risk and livelihoods in a new look at food security recognised the importance of vulnerability of households and the historic patterns that may have caused the current level of insecurity (Swift and Hamilton 2001). It also introduced the notion of resilience to food security perspectives with three types of households outlined by Oshaug (1985): enduring, resilient, and fragile households.  This approach extended the individual approach to studying food security introduced by the first paradigm shift even further and could be applied in a rural or urban context. The ideas of resilience and sensitivity provided a strong framework for the analysis of food security over time with the least secure households defined by high sensitivity and low resilience (Swift 1989). By the end of the 1990’s the concept of sustainable livelihoods was established and defined as follows:

A livelihood comprises the capabilities, assets (including both material and social resources) and activities required for a means of living. A livelihood is sustainable when it can cope with and recover from stressors and shocks, maintain or enhance its capabilities or assets, while not undermining the natural resource base (Scoones 1998: 5)

Assessing food security at a household level and through a sustainable livelihoods framework allows for the incorporation of concerns of poverty, gender issues, farming systems and governance (Swift and Hamilton 2001). The sustainable livelihoods approach realistically saw food security as just one aspect of survival within poor households (Davies 1996). Four important changes to the perspective on food security were introduced (Ericksen 2008). Firstly, as mentioned, the multiple objectives of households were recognized (Swift and Hamilton 2001). Secondly, the understanding that agriculture is not always the primary source of income and that other markets and economic trends play a role in household security (Ellis 2000). Thirdly the environment is recognised as an important asset (Scoones 1998), and lastly institutions were recognised as important in distributing and arranging both social and economic capital through fostering household livelihood strategies at multiple levels (Swift and Hamilton 2001). The new approach thus allowed for a broader understanding of the drivers and vulnerabilities causing food insecurity beyond a food first approach and an entitlements approach.

As the concept of food security changed the means of measuring food security was forced to change, thus the third paradigm shift began to take place (Maxwell 1996). Coming to grips with a personal level of assessment of food security meant that objective definitions of food security, such as sufficient calories per day, were no longer adequate (Maxwell 1996). A new subjective approach to food security was necessary. Subjective definitions of poverty have been recognized since the 1970’s (Townsend 1974) and their introduction to the concept of food security marks an important shift in understanding human needs and cultures.

It was recognized by Payne (1990) that definitions based on calorie requirements calculated using average adults and children and average levels of activity should be subject to constant revision as conditions change, and that nutritional requirements change as a function of health, size, workload and environment (Payne and Lipton 1994). A calorie requirement, which may have seemed like a simple means of measuring food security, was far more difficult when individuals are taken into consideration. It became increasingly obvious that a quantitative approach would not suffice (Maxwell 1996), and a new definition of food security was needed which could account for the complex individual physical and cultural dimensions of food.

The argument was then made that food security can only be obtained when access to quality, nutritionally adequate food which is culturally acceptable is possible without loss of dignity and self-determination and is consistent with access to other basic needs (Maxwell and Smith 1992). These definitions require reference to food insecure people as a means of understanding the delicate balances and trade-offs made in the search for food security, and as such subjective questioning and local level studies are imperative to the realisation of food security (Minhas et al. 1990; Bickel et al. 2000).

The 1990’s saw food security studied as a multi-disciplinary field and began with the International Conference on Nutrition jointly organized by the FAO and the World Health Organisation. The following years saw conferences on Human Rights (in 1993), Overcoming Global Hunger (also 1993), Social Development (World Summit in 1995) and eventually the World Food Summit (WFS) in 1996 (Shaw 2007). The frequency of international conferences can perhaps be seen as a mark of the global recognition of the problems of food security and poverty in the developing world and a result of the three important paradigm shifts leading to a more inclusive view of the possible causes of these widespread problems. The WFS resulted in a new definition of food security which has remained as the primary definition for the last quarter century:

Food security exists when all people, at all times, have physical, social and economic access to sufficient, safe, and nutritious food that meets their dietary needs and food preferences for an active and healthy life (FAO 1996: 2)

This definition was re-enforced in 2009 and extended to include four pillars of food security: availability, access, utilization, and stability (FAO 2009: 1). This definition is comprehensive and calls for action at all levels (Ecker and Breisinger 2012). The stipulation of an active and healthy lifestyle has more global bearing today than ever before. Previously the focus of food insecurity lay on the developing world and on health issues associated with under nourishment and starvation. In the last few decades, in fact since the 1970’s, obesity rates have been increasing in almost all demographics (Sassi et al. 2009). A shift has begun whereby global obesity rates are higher than previously recorded with an estimated 1.46 billion adults having a body mass index (BMI) of above 25kg/m²  of which 502 million adults were technically obese with BMI greater than 30 kg/m² in 2008 (Finucane et al. 2011). This gross extremism in food caloric shortage and surplus must be attributed to a failing food system (Swinburn et al. 2011).

Through the many definitions of food security over the past 40 years it appears as though we have settled on one that is able to incorporate the extremely complex nature of individual needs, entitlements, lifestyles and cultures. However the long term focus on the connection between poverty, underdevelopment and the global south has led to a one-sided view of food security which is only just coming into focus. Studies on food deserts and food swamps are now necessary in already developed countries of the global north (Rose et al. 2009). The future of food security studies must now embrace a world even more complex than previously imagined where morbidity as a result of lack and excess of food coexist.

A further complication to current perceptions and studies of food security and the food system is a changing climate. Climate change may affect food systems in multiple and unpredictable ways (Gregory et al. 2005). The realisation of the stress of Global Environmental Change (GEC) on the food system prompted the development of programmes such as the Global Environmental Change and Food Systems (GECAFS) which aims to improve the understanding of the relationship between the food and earth systems (Ingram et al. 2005). The system is more complex than ever and this has inspired the application of a socio-ecological systems (SES) approach (Ericksen 2008), whereby GEC drivers interact with socio-economic factors to impact food system outcomes related to stability, access and utilisation of food, and the GEC drivers are analysed through food system activities such as production, processing and distribution.

Ever more complex approaches to solving the global food security problem are being developed. The perspectives have evolved immensely in the last 40 years despite the failures to meet many of the goals set by the multiple summits and conferences over the decades. The problem is now, more than ever a humanitarian one, as it is increasingly obvious that the resources and knowledge required to end this century old problem exist.                                                               

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References

Bickel, G., Nord, M., Price, C., Hamilton, W. & Cook, J. 2000, "Guide to measuring household food security", Alexandria.Department of Agriculture Food and Nutrition Service.

Borlaug, N.E. 2000, "Ending world hunger. The promise of biotechnology and the threat of antiscience zealotry", Plant Physiology, vol. 124, no. 2, pp. 487-490.

Brown, L.R. 1969, Seeds of change. The Green Revolution and development in the 1970's. Pall Mall Press, London.

Davies, S. 1996, Adaptable livelihoods: coping with food insecurity in the Malian Sahel. Macmillan Press Ltd.

De Waal, A. 1991, "Famine and human rights", Development in Practice, vol. 1, no. 2, pp. 77-83.

De Waal, A. 1989, "Famine mortality: A case study of Darfur, Sudan 1984–5", Population Studies, vol. 43, no. 1, pp. 5-24.

Devereux, S. 1993, Theories of famine. Harvester Wheatsheaf.

Devereux, S. & Maxwell, S. 2001, Food security in sub-Saharan Africa. ITDG Publishing.

Dreze, J. & Sen, A.K. 1991, Hunger and public action, Oxford Clarendon.

Ecker, O., & Breisinger, C. 2012. The Food Security System: A New Conceptual Framework, IFPRI Discussion Paper 0166 March 2012

Ellis, F. 2000, Rural livelihoods and diversity in developing countries, Oxford University Press.

Ericksen, P.J. 2008, "Conceptualizing food systems for global environmental change research", Global Environmental Change, vol. 18, no. 1, pp. 234-245.

FAO (Food and Agriculture Organization). 1983, Director’s General Report on World Food Security: A Reappraisal of the concepts and approaches; Committee on Food Security, CFS. 83/4

FAO (Food and Agriculture Organization). 1996. Rome declaration on world food security and World Food Summit Plan of Action. Tech. Rep., Food and Agriculture Organisation, Rome.

FAO (Food and Agriculture Organization). 2009. Declaration of the World Summit on Food Security, WSFS 2009/2. Food and Agriculture Organisation of the United Nations, Rome.

Finucane, M.M., Stevens, G.A., Cowan, M.J., Danaei, G., Lin, J.K., Paciorek, C.J., Singh, G.M., Gutierrez, H.R., Lu, Y. & Bahalim, A.N. 2011, "National, regional, and global trends in body-mass index since 1980: systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9· 1 million participants", The Lancet, vol. 377, no. 9765, pp. 557-567.

Gregory, P.J., Ingram, J.S. & Brklacich, M. 2005, "Climate change and food security", Philosophical transactions of the Royal Society of London.Series B, Biological sciences, vol. 360, no. 1463, pp. 2139-2148.

Harsch, E. 1992, “Enhanced food production: An African priority”, Maxwell (ed.), Food Security in Africa: Priorities for reducing hunger, Africa Recovery Briefing Paper No. 6, United Nations Department of Public Information, United Nations, New York.

Hopkins, R.F. 1986, "Food security, policy options and the evolution of state responsibility", Food, the state, and international political economy: dilemmas of developing countries., , pp. 1-36.

Ingram, J., Gregory, P. & Brklacich, M. 2005, "GECAFS science plan and implementation strategy", ESSP report, Wallingford, vol. 2.

Maxwell, S. 1996, "Food security: a post-modern perspective", Food Policy, vol. 21, no. 2, pp. 155-170.

Maxwell, S. & Smith, M. 1992, "Household food security: a conceptual review", Maxwell and Frankenberger (ed.), Household Food Security: concepts, indicators, measurements. Rome and New York: IFAD and UNICEF.

Minhas, B.S., Jain, L., Kansal, S. & Saluja, M. 1990, "Rural Cost of Living: 1970-71 to 1983 States and All-India", Indian Economic Review, vol. 25, pp. 75-104.

Oshaug, A. 1985, "The composite concept of food security", Introducing nutritional considerations into rural development programs with focus on agriculture: a theoretical contribution. Oslo: Institute for Nutrition Research, University of Oslo.

Payne, P.R. & Lipton, M. 1994, How Third World rural households adapt to dietary energy stress: The evidence and the issues, Intl Food Policy Res Inst.

Payne, P. 1990, "Measuring malnutrition", IDS Bulletin, vol. 21, no. 3, pp. 14-30.

Rose, D., Bodor, N., Swalm, C., Rice, J., Farley, T. & Hutchinson, P. 2009, "Deserts in New Orleans? Illustrations of urban food access and implications for policy", Ann Arbor, MI: University of Michigan National Poverty Center/USDA Economic Research Service Research.

Ruel, M.T., Garrett, J.L., Morris, S.S., Maxwell, D., Oshaug, A., Engle, P., Menon, P., Slack, A. & Haddad, L. 1998, Urban challenges to food and nutrition security: A review of food security, health, and caregiving in the cities, IFPRI Washington, DC.

Sassi, F., Devaux, M., Cecchini, M. & Rusticelli, E. 2009, "The obesity epidemic: analysis of past and projected future trends in selected OECD countries", Organisation for Economics Co-Operative Development.

Sen, A. 1981, The Food Problem: Theory and Policy, Third World Quarterly vol. 4, no. 3, pp. 447-459.

Shaw, J.D. 2007, "World Food Security: A History since 1945”. Palgrave, Basingstoke

Stevens, C., Devereux, S. & Kennen, J. 2003, "International trade, livelihoods and food security in developing countries". IDS Report, Institution of Development Studies, University of Sussex, Brighton.

Swift, J. 1989, "Why are rural people vulnerable to famine?", IDS bulletin, vol. 20, no. 2, pp. 8-15.

Swift, J., Hamilton, K.. 2001, "Household food and livelihood security.", Devereux & Maxwell (eds.) Food security in sub-saharan Africa, ITDG Publishing., pp. 67-92.

Swinburn, B.A., Sacks, G., Hall, K.D., McPherson, K., Finegood, D.T., Moodie, M.L. & Gortmaker, S.L. 2011, "The global obesity pandemic: shaped by global drivers and local environments", The Lancet, vol. 378, no. 9793, pp. 804-814.

Townsend, P. 1974, "Poverty as relative deprivation: resources and style of Living", Wedderburn (ed.), Poverty, Inequality and Class Structure.

UN (United Nations) 1975, Report of The World Food Conference, Rome: New York 5-16 November 1974.

World Bank (1986) Poverty and Hunger: Issues and Options for Food Security in Developing Countries. World Bank Policy Study. World Bank, Washington, D.C.

Climate Change, Sustainable Development and Food Security

Last year I completed my honours in Biological Sciences. A monthly task set by the degree formed this blog which was meant to cover interesting new work in any biological field. During the course of the year I began to feel a need to work with the human part of the climate change problem which drew me towards the ACDI masters programme co-ordinated through the department of Environmental and Geographic Sciences at UCT.
My world has since shifted.

I don't think I'll have time to update this regularly but I am hoping to share some of the essays, assignments and programmes I hear of throughout the course of the year.

All feedback welcome.

Response to the Western Cape Government Green Economy Strategy Framework

Sustainable Development is the latest buzzword in the circle of individuals interested in the social aspects of climate change. The reality of an uncertain and unpredictable future necessitates drastic changes at a political and developmental level as adaption and mitigation are not necessarily options for the billions of individuals in developing nations around the world. Society has begun to realise that climate change is no longer an unknown on our collective doorstep but rather a system that is changing and negatively impacting millions of people. The largest impacts seem to be felt in developing and poor nations where the infrastructure and wealth are not available to mitigate the lack of basic resources such as food and water, especially in the face of extreme weather events such as floods and droughts which are increasing in magnitude and frequency worldwide. Solving the problems of developing nations in the face of a changing climate seems to make sense only through some sort of sustainable development.

Sustainable development is not a new term; in fact it was loosely defined for the first time in the 1987 Report on the World Commission on Environment and Development (Brundtland 1987). This report, commonly referred to as the Brundtland report, emphasised the need for economic growth as a means of keeping up with population growth and alleviating the crippling poverty that leaves millions of people vulnerable to the effects of global climate change. The report highlights the importance of merging environmental and economic goals as well as social development in the processes of decision making. The applications of these concepts lies in the hands of government and policy makers and it is in the light of sustainable development that I would like to present the Western Cape Government’s Green Strategy Framework (WCG 2013).

A commonly noted problem with development in third world and poor nations is the issue of the cost of ‘green’ development compared to the cheap fossil fuel fired development enjoyed by already industrialised nations. Undeveloped countries face the mammoth challenge of trying to catch up to developed countries, alleviate poverty and the associated evils, and reduce or nullify any environmental impact. This is the paradox of desiring economic growth while avoiding environmental harm. South Africa is a developing country; however the Western Cape is a unique case in that a relatively high level of industry and infrastructure already exists and the provincial government has made the decision to become the lowest carbon province and a green hub of the African continent (WCG 2013).

The premier of the Western Cape, Helen Zille, stated in 2013 that the province aims to become the leading green economic hub, not only in South African, but on the African continent. This will supposedly be achieved through the ‘Green is Smart’ programme outlined in The Green Economy Strategy Framework (WCG 2013). The strategy hinges on five smart ‘Drivers’: Living & Working, mobility, eco-systems, agri-production and enterprise. These drivers are said to be made possible through five ‘Enablers’: Infrastructure, Capabilities, Knowledge Management, Rules and Regulations, and Finance. The Framework ‘Green is Smart’ outlines multiple projects and initiatives with both market and private sector focus which are aimed to catapult the economy of the Western Cape through growth and into sustainability. This strategy is a step away from the traditional development practices of the third world, which are largely fossil fuel dependent, and towards the smart, but ambitious, sustainable development route. In her State of the Province Address, Helen Zille stated that the Western Cape green economy formed part of the R2 billion worth of foreign direct investment (FDI) over the last four years (SAnews.gov.za 2014).

The ‘Green is Smart’ Framework acknowledges that the Western Cape  is predicted to be one of the provinces most negatively affected by climate change and cites this as a primary incentive for a shift to a green economy. Both the Framework and Finance and Economic Development MEC Alan Winde, state that the Framework is the best way to mitigate the threat of climate change (Barnes 2013, WCG 2013). Statements such as these identify a gap in the understanding of the effects of climate change and the real goal of sustainable development. A green, oil independent future is surely the smartest option given the current state of affairs but a green economy certainly does not remove the risks and effects of an already largely altered climate. In light of global climate changes perhaps instead of a green economy framework the provincial government should be looking to sustainable livelihoods and economic self-sufficiency.

Although some of the goals of the Framework seem misaligned, such as the possibility of reducing the impact of climate change on the province through a shift to a green economy, the goal is aligned with one of the major policies of Helen Zille’s party, that of job creation. The Framework is said to be likely to create 12 000 jobs by 2015, 16 000 by 2020 and 20 000 by 2025 (Barnes 2013). This is a necessary attempt to curb the extremely high unemployment rate in the Western Cape and is recognition that the quality of economic growth is as important as growth itself. A problem recognized by the Brundtland report is that growth is inherently unsustainable. The concept of sustainable development, according to the report, should centre on the satisfaction of human needs which, in developing countries, are food, clothing, shelter and jobs (Brundtland 1987). The Green Economic Framework seems only concerned with a fraction of these basic needs and as such is not a sustainability report.

The Western Cape is the first provincial government to prepare a document of this form and is a major step towards supporting sustainable projects on a provincial level. The national government recognises the importance of growth in the green business sector. Jacob Zuma stated, after his State of The Nation Address, that the green economy is a vital area of growth as the formal economy cannot absorb all job seekers (SAnews.gov.za 2014). What it comes down to is actual implementation of these projects and the action to achieve these goals. The Brundtland report’s section on sustainability ends with the key point “What matters is the sincerity with which these goals are pursued and the effectiveness with which the departures from them are corrected” (Paragraph 82 Chapter 2, Brundtland 1987). A governing body which cares about the quality of growth and the future livelihood of its people is far ahead of one which merely recognises that Green is Smart and that growth is necessary.

                                                                                                                                    

References

Brundtland, G.H. 1987, "World Commission on Environment and Development (1987): Our Common Future", World Commission for Environment and Development.

Western Cape Government, 2013, Green is Smart. Western Cape Green Economy Strategy Framework 2013.

Premier Zille outlines W Cape state of Affairs 2014, accessed 03 March 2014, http://www.sanews.gov.za/south-africa/premier-zille-outlines-w-cape-state-affairs

Barnes, 2013. Cape plans to green economic hub, accessed 03 March 2014, http://www.iol.co.za/business/news/cape-plans-to-green-economic-hub-1.1546665#.UxRFffm4qgg

LANDSCAPE ECOLOGY: A COMPLEX APPROACH

This is the essay I wrote for the Honours mid-year Theory Seminars, it's quite long and complex but I really enjoyed writing it and maybe it will actually be read here.

Introduction

The biggest questions facing humanity, and especially ecologists, in the 21^st century involve our relationship with our surroundings. Advances in technology and industry, as well as an exponentially expanding population, result in an immense pressure that is placed on the ecosystem. For this reason special attention is required to understand the systems that we rely on and which are most affected by our actions. Landscape ecology is one field which offers a host of tools to study ecosystems with a sociological component. Landscapes exist as a manifestation of ecosystems on a scale that is specifically and explicitly important to humans. The scale at which humans interact with the environment is critically relevant in this field of ecology.

 A key problem facing ecologists is the loss of biodiversity and the potential implications for services on which humans depend. Loss of services includes, among others, decreased water quality and disrupted pollination systems or nutrient cycles. An understanding of the fundamental processes which govern these systems seems imperative to ensure a healthy socio-ecological future. However, the ecosystems which govern these relationships form extremely complex systems in which interactions at macro-scales influence processes, trophic-structures, productivity and nutrient fluxes among components and various scales. The interactions of the components of the system accordingly feed back into the macro-scale resulting in a hyper complex system, the understanding of which is vital in resolving the issues facing mankind today (Levin 1998).

Our current understanding of the systems that govern ecology encompasses various facets from community compositions to molecular ecology and from the study of a single plant to the biogeography of biomes. Major jumps in our understanding of the processes entailed in ecology are rare, and in this sense the emergence of a new field is particularly noteworthy. One field specifically studying the relationships between patterns and processes is the relatively young field of landscape ecology. The development of this field has been aided by increases in landscape use and change over the last century (Risser and Iverson 2013) and the field has undergone an interesting evolution from its founding days as a subject struggling to combine small scale biotic studies with large scale land use changes to one which is multidisciplined and actively incorporates a range of scales. The field has grown from one with little definition into one of the most mathematically intriguing and complex fields in ecology today. The search for multiscale patterns has extracted landscape ecology from a simple descriptive field into one that may blur the lines between mathematics, physics, chemistry and ecology. In addition landscape ecology has approached a fascinating point in which the human imposed definitions are likely to be redefined through the application of complex systems theory. The complex practices entailed in landscape ecology today may be one of our greatest defences in a rapidly changing and unpredictable world.

The emergence of Landscape Ecology

                For decades, if not centuries, the need to understand our surroundings has both captivated and haunted biologists and geographers. Those most afflicted with the desire, dedicated their lives to the understanding of landscapes, and this work was encouraged by the historic need for planning in increasingly human-dominated landscapes. Before biologist and botanist Carl Troll coined the term Landscape Ecology in 1939, the bulk of work on this topic was constrained to geography, botany and ecology in a land-use framework (Risser et al 1984). At this time there was no canonical definition of a landscape and the pioneers of landscape ecology had varying ways in which they approached the topic but it was essentially viewed as landscape geography. The foundation of the subject has firm rooting in Europe; however the field had little focus as evident by the many definitions of the subject and the approaches used. For example Troll defined landscapes as an objective “organic entity” (Troll 1950), while his contemporary Ernst Neef, defined landscapes in terms of the uniformity and specificity of their land-use (Neef 1967). These two definitions are inherently different: Troll’s view, contrary to Neef’s, leads to the understanding that a landscape is not a mental construct which can be redefined in an anthropocentric relativistic way. The view of a landscape as separate from the definitions imposed by human understanding is paramount to the development of landscape ecology.

The simultaneous shift in ecological studies from individual organisms, populations and community structure to ecosystem analysis, from the 1940s to the 1960s, aided the development of the field of landscape ecology (Risser and Iverson 2013). In the 1970s “landscape-level” studies attained a “level” of prominence, especially in Europe where the field was recognized as landscape geography (Risser et al 1984). In addition theoretical and technical advancements in ecology such as island biogeographic theory, patch dynamics and spatial simulation modelling, were steadily growing and raising interest in the spatially heterogeneous and complex processes governing patterns. Despite this interest, by the beginning of the 1980s there was still no generally accepted framework which could incorporate the diverse ideas of multiple landscape patterns and the movement of energy and organisms across spatially heterogeneous landscapes. Developments in the use of mathematical models, especially in population biology (Levin 1968), began to play a role in landscape ecology and allowed for growth in ecosystem science.  Very little attention, however, was paid to spatial heterogeneity, and very few models incorporated a spatial component (Risser and Iverson 2013).

In the early 1970s the United States of America’s National Science Foundation (NSF) ran the International Biome Program (IBP) which conducted studies on managed and unmanaged geographic ecosystem types; it involved measurements within ecosystem types as well as ecosystem-level mathematical models. The studies began to recognize the importance of heterogeneity in the interactions between sub-units. High levels of heterogeneity complicated attempts to select and interpret the roles of driving variables. The results of the IBP led to the NSF’s Long-Term Ecological Research project (running from the late 1970s and continuing today) which aimed to include landscape heterogeneity in its design and in its measurement of biodiversity, productivity and abiotic cycles (Risser and Iverson 2013). In light of these programmes and the undeniable importance of heterogeneity in landscape research, the NSF granted funding to the Illinois Natural History Survey – whose goal had been to develop a large Geographic Information System for Illinois – to hold a workshop which would strive to outline and contextualise the directions and approaches of “landscape ecology” as a developing field. Little did the attendees of the workshop realise that the discussions of those three days in rainy Allerton Park, Illinois, would define a new paradigm in ecology, especially in the United States (Risser and Iverson 2013). The workshop was led by Paul Risser, Richard Forman and James Karr with 25 participating ecologists, including one representative each from Canada and France, and the remainder from the United States (Risser and Iverson 2013). All of the attendees were experts in their field and none realised that they were outlining an essentially new multifaceted field in ecology (Risser 1984,Wu 2013).

There were two essential outcomes of the Allerton Park workshop, as outlined in Risser and Iverson’s 30 year anniversary review (Risser and Iverson 2013). The first served to define landscape ecology and the second solidified the importance of the field in the understanding of ecological processes with respect to heterogeneity. Risser (1984) reported on the workshop and describes the outline of what was to become the North American vision of landscape ecology:

“Landscape ecology is not a distinct discipline or simply a branch of ecology, but rather is the synthetic intersection of many related disciplines…, viewing landscape ecology as a branch of ecology, would…tend to exclude the formal analysis of human cultural processes that form landscapes…. Understanding landscapes requires that we deal with human impacts contributing to the landscape phenomenon, without attempting to draw the traditional distinction between basic and applied ecological science or ignoring the social sciences”

In the last three decades of landscape ecology key questions, the basis of which were raised at the Allerton Park workshop, have been expanded upon and defined. A review of landscape ecology on the 30^th anniversary of the workshop by Wu (2013) outlines some of the defining questions and topics of landscape ecology, as demarcated then and as facing the science today. The report released after the workshop (Risser et al 1984) defined the questions as follows: (1) “How are fluxes of organisms, materials and energy related to landscape heterogeneity?” (2) “What past and present processes result in the patterns seen in landscapes?” (3) “How is the spread of disturbance affected by landscape heterogeneity?” (4) “How can an understanding of landscape ecology improve resource management practices?” These four basic questions are no less valid today than they were 30 years ago, although the science has come a long way in answering parts of them (Wu 2013). Wu (2013) outlines an updated version of these questions. As the science has grown, so have the sciences on which landscape ecology can draw, especially those lending to analytical processing, computing capacity and mathematics of complex systems, allowing an expansion of the questions that landscape ecology can ask, and concurrently answer. In 2001 the US Association of Landscape Ecology held their 16^th symposium at which the “Top 10 List for Landscape Ecology in the 21^st Century” was produced through contributions from 15 leading landscape ecologists. Wu (2013) elaborates on these 10 key research topics, as follows: (1) ecological flows in heterogeneous landscapes, (2) processes, causes and consequences of land-use and land cover change, (3) nonlinear dynamics and landscape complexity, (4) scaling, (5) methodological development, (6) landscape metrics and related processes, (7) integrating anthropogenic effects into landscape ecology, (8) optimization of landscape pattern, (9) landscape sustainability, and (10) data acquisition and accuracy assessment. The four original questions outlined at Allerton Park are still prevalent in ecology today, allowing for some modernization while the introduced questions show the range of interest that has developed in the field.

Of the 10 key topics that outline the direction of landscape ecology, the concept of nonlinear dynamics and complexity has led to a remarkable coalition of the fields of ecology and mathematics. The need to identify patterns, already in themselves complex, at various scales of space, time and organizational complexity, is a cornerstone of landscape ecology. Due to this feature of the science the adoption of the concept of complex adaptive systems has benefited the field of landscape ecology. Before the idea of complex adaptive systems was introduced to landscape ecology by figure heads such as Milne (1998) and Levin (1998), the main approach to understanding the complexity of landscapes was the paradigm of hierarchies (Urban et al 1987). By the late 1980s the idea of a landscape as a mosaic of patches generated by processes operating at various scales was widely accepted (Urban et al 1987). The formation of these patterns had been in consideration for some years, with Levin’s (1978) work on planktonic communities as an ideal study for patterns functioning over patches. Based on this research, patterns were thought to be results of disturbances, biotic processes and environmental constraints with each of these processes acting at different scales, both within and across processes (Levin 1978). This level of complexity in landscape ecology has been approached from two main perspectives in the last 30 years; that of a set of nested levels of processes and interactions (the “hierarchy approach”), and that of studying each level and the translation from one level to the next (the “complex adaptive systems approach”).Both ideas, which are indeed linked, will be discussed in the following section of this essay.

Tackling Complexity

The inherent complexity of landscapes necessitates a multiscale or hierarchical approach in its analysis. Urban et al (1987) applies a definition to landscapes which has become somewhat traditional, specifically that landscapes are seen as a mixture of patches of various size, of various origins, in various stages of regeneration, approaching microenvironmental equilibria at various rates. Hierarchy theory views the complexity of this landscape as patterns organized in a special way, with processes and patches occurring at characteristic scales. In particular these scales are positively correlated in space and time (Figure 1). In general, low-level events occur on a smaller scale with more frequency than do large-scale events. The characterisation of these scales allows for the complexity to be viewed as containing a degree of organization which can be broken down into levels. Hierarchy theory provides guidelines for defining the levels of a system.

Figure 1. The scaling of vegetation patterns across time and space (Urban et al 1987)

The levels of the system are nested and when viewed as individual parts, can contribute to an understanding of the complexities of the landscape. Hierarchy theory thus allows for explanations of landscape ‘behaviour’ as the interaction among the parts, and of patterns that translate across the hierarchical scales. Importantly the levels of a system are related to each other and are functionally defined. This is a mentally constructed way of viewing a landscape, the primary benefit of which is the ability to resolve the complexity of dynamics and spatial patterns at a range of scales into a few variables and a set of constraints each relative to the reference level.

Hierarchy theory did not evolve as a consequence of landscape ecology, rather it is a concept already viewed as classical by Urban et al (1987), which was merely applied as a paradigm for understanding the complexity of landscapes. The formal view of hierarchy theory is commonly thought to have been introduced to landscape ecology by Allen and Starr (1982); however Urban et al (1987) recognise the early work by Watt (1947) and Whittaker (1953) in defining the concept.

Hierarchy theory as formally applied defines a three-tiered nested system in which the levels are relatively isolated and each level operates at distinct scales; however the boundaries of the levels may be difficult to define. Concepts of the theory usually apply to scale-related principles while many of the real world applications involve organizations defined by human-centric concepts such as populations or biomes, which may be inappropriate for the description of underlying processes (Hay 2002). Despite this downfall in hierarchy theory, the idea of levels in a landscape is exceedingly useful and likewise plays a part in complex theory.

The arrival of Remote Sensing as a tool to capture the patterns of landscapes allowed for a new framework to be adopted by landscape ecologist. The plethora of information available, in addition to the increase in computational power, made the processing of characteristics of systems with a large number of components interacting in non-linear fashions and exhibiting adaptive properties possible.  This new framework builds on Complex Systems theory and mathematics from the 1960s and 1970s and has been used in economics, computer science and more recently, ecology (Hay 2002). Landscapes when viewed from a complex systems approach have an updated definition from the one outlined by Urban et al (1987).In this light, landscapes can be seen as “open systems that extract high quality energy from the sun, and respond with the spontaneous emergence of organized behaviour so that their structure and function are maintained” (Kay and Schneider 1995). An important characteristic of complex systems is that they lend themselves to a nested hierarchical structure, and complexity theory views these hierarchies in a slightly different way to that of conventional hierarchy theory. A fundamental characteristic of Complex Systems is the appearance of levels and of self-organization.

Complexity as a science is difficult to define as it entails a vast assembly of contrasting approaches. A few of the many concepts and approaches include cellular automata, interacting particle systems, self-organization, non-linear dynamic systems, fractals, and artificial life (Milne 1998). Complexity in itself can be approached in two distinct ways, one way embraces the complexity as an inevitability and studies it by breaking it down into subsets defined and controlled by a small number of processes. This first view correlates well with the hierarchies paradigm, however if the complexity of the living system emerges from a large number of random associations and interacting factors then the system is appropriately complex to be studied through the framework of complexity theory, the second way in which to view a complex system. Complexity theory draws on ideas, concepts and theories from Catastrophe theory, Chaos theory, Hierarchy theory, Non-Equilibrium Thermodynamics and Self-Organization theory (Hay 2002). According to complexity theory the levels that emerge are a result of the systems self-organization.

By applying a complex systems approach to ecology, the natural levels which emerge in the complex system can be investigated through the analysis of a multitude of variables in multifarious models in which the levels and hierarchies are made obvious by scale thresholds separating scale domains represented by sharp transitions in patterns (Meentemeyer 1989). The advances in complexity theory provide opportunities for landscape ecology as the study of a non-linear system which includes feedbacks leading to a self-organized behaviour over a wide range of spatial and temporal scales (Levin 1992). In addition a complex systems approach enables a synthesis of the understandings developed for each level in a system and translating that theory from one layer to another (Milne 1998). One aspect that may help to cement the application of complexity theory to landscape ecology can be seen in the study of scaling relations. Scale, as mentioned, is one of the key aspects of landscape ecology, the search for invariant scaling relations and the possible processes that generate them makes up a large portion of the work done in the field (Wiens and Milne 1989). Scaling relations can be used to delineate the domain of a hierarchy level (Milne 1998).

The discovery of scaling relationships that exist in this way would indicate that the system is controlled by first principle rules that occur across a range of scales (Meakin 1993). Traditionally biological sciences operate in a framework that emphasizes analysis of variance in a somewhat descriptive sense. Descriptions tend to be based on interest levels which exist in the frame of the viewer, as such processes and patterns tend to be anthropocentrically defined. The search for invariant scaling relations is in contrast with these ideas, complexity theory searches for invariant system properties which may transcend the boundaries of the human conceptual frameworks. The current state of the application of complex theory is working to objectively reveal domains of length and time scales over which processes operate (Wiens and Milne 1989).

Complex Adaptive Systems

The ecosystem is a complex system which presents itself in a different way to other complex systems as it involves adaptability and sustained diversity. These two points define the biosphere as a special type of complex system known as a complex adaptive system (CAS). Descriptions of other CAS’s can be found in Arthur et al (1997) especially as applied to any economy. Examples of CAS’s are found in everything from cells to meta-communities and the idea was applied to ecosystems as recently as 15 years ago. Levin (1998) championed the usefulness of a CAS approach to ecosystems, in particular as a tool to investigate the relationship between the organization of biodiversity and the functioning of systems.

Not all complex, self-organising systems are adaptive and Levin (2003) outlines the point that in order to be considered adaptive some form of selection must take place, and in these situations it is crucial to distinguish at what levels selection is taking place. This task is non-trivial, and may be impossible as selection may be occurring on multiple interacting scales. In general Levin (2003) defines CAS’s according to three properties: (1) Diverse range of individual components, (2) localized interactions among components, and (3) a self-directed process that uses feedback systems and the outcomes of the interactions in order to enhance the state of the system. Complex adaptive systems are thought to contain a level of self-organization which emerges in the form of patterns at higher levels and are a result of localized interactions and selection processes at lower levels (Levin 1998).

The basic properties of a CAS have been proposed in many different ways (Levin 1998), one slightly different way was outlined by Holland (1995) in identifying four properties of any CAS:

Aggregation – Basic elements of a system are inhomogeneously organized, as such patterns of hierarchies are a natural consequence of self-organization and an essential element in the development of a system. It is important that the hierarchies and assemblages are not imposed on the system by any human definition; rather they emerge as a feature of CAS’s.

Non-linearity – Local rules of interactions in a system change as the system develops. This is seen in the systems dependence on the chance events which occur at the system’s inception. The events at the beginning set the system on a path which it is in some way restricted to. This feature manifests as resilience in some systems.

Diversity – The generation and maintenance of diversity is fundamental to adaptive evolution and it is therefore necessary in adaptive systems. Diversity within functional groups allows for buffering and homeostasis for critical ecosystem processes.

Flows – Fluxes of energy, material and information characterise any system and allow for interconnectedness of the components of an adaptive system, without which individuals would be existing in random collections. Flows are responsible for the way in which the self-organization emerges.

The ecosystem displays these properties (Levin 1998) and therefore the application of complex theory to ecosystems is opening up a new way in which to view the systems landscape ecologists have been attempting to understand for centuries.

Applications of Complex Systems Theory

In the case of CAS’s, and complex theory in general, a major deterrent to its entrance into the main stream is the host of non-trivial mathematics that accompany the theories. Although mathematics and complexity are daunting subjects, they are inherently objective and can therefore enlighten our understanding of systems if understood and appropriately applied. The field of complex systems is relatively new and applications and empirical evidence is not something that can easily be found in landscape ecology. However there are a few interesting studies which are applying the concept of complex theory to ecosystems and in this way revealing a host of promising and interesting ways in which landscapes and ecosystems can be understood.

One such example of this is in the prediction of critical transitions in systems (Scheffer et al 2009). Complex systems have been shown to have tipping points in which a sudden shift to a contrasting regime may occur, this is apparent in many systems including medicine and economics but has also been seen in ecosystems (Scheffer et al 2001). By adopting the complex systems approach these points may be predicted (Scheffer et al 2009). So far work on basic models has produced remarkable accuracy in predicting transition points, while application of the method to more complex systems is showing promise. Examples in landscape ecology have been found, such as self-organization in vegetation patterns possibly indicating imminent vegetation loss (Rietkerk et al 2004), and, in systems ruled by local disturbance, scaling laws which govern the structure of patterns have been found to vanish as a critical transition approaches (Kéfi et al 2007).

The technique of renormalization group analysis is one that was developed in physics (Creswick et al 1992) and can be applied to landscape ecology in a complex systems approach. The technique allows for thresholds and domains to be detected as critical phenomena (Milne 1998). The renormalization strategy aims to determine processes at the level of the individual and aggregate the system to coarse scales in order to make predictions of scaling exponents for macroscopic patterns (Creswick et al 1992). An example of the application of this concept to a landscape occupied by trees is provided in detail in Milne (1998). Scaling and renormalization approaches contrast with traditional approaches to ecology which tend to focus on empiricism and analysis of variance, this approach searches for invariant system properties (Milne 1998) and can be thought of as a more “first principles” approach to modelling systems.

The acceptance of landscapes as complex systems has facilitated collaboration between ecology and computer science, especially in the form of remote sensing and spatial analysis. Growth in technology of data collection at large scales and extents with high resolution has provided an excess of multi-spatial, multi-spectral, and multi-temporal resolution data (Hay 2002). This ability to observe landscapes at a large scale, along with complex data analysis tools such as Scale-Space theory (Lindeberg 1994), creates the possibility of a framework which may assist in automatically defining critical landscape thresholds, domains of scale, ecotone boundaries, and the grain and extent at which scale-dependent ecological models could be developed  (Hay 2002, Blaschke and Hay 2001).

A Better Approach

The use of a complex systems approach to landscape ecology works to fundamentally remove any bias that could be applied to ecosystems by the human scale that we perceive the world to function at. By fully embracing the complex systems approach it seems it may be possible to allow landscape ecology to express its own laws and define its own boundaries. Although many of the boundaries and patterns that we observe may be rightly attributed to processes, especially as some may coincide with the scale at which we perceive the environment, however the possibility of revealing unknown processes, scales or levels is too exciting to ignore.

Given the necessity to understand the processes that govern the ecosystem that we depend on a solid framework for viewing the landscapes is imperative. Ernst Neef may have been introducing the bias of human construct to landscapes when he classed them as large scale spatial arenas in which humans interact with the environment, but he was not wrong. Our landscapes, although separate entities which have their own processes and patterns, are the most direct link that humans have to the ecosystem. For this reason, I believe that an understanding of the complexity of the processes that govern the patterns of the ecosystem in which we exist, is of the utmost relevance. There is no doubt that by understanding the mechanisms behind biodiversity, species assemblages, vegetation patterns or energy flows through a system, we can optimize our management of these systems and thus better utilise and conserve them.

The growth of landscape ecology over the last 30 years is a remarkable story on its own. Adding in the revolutionary approach of conceptualising systems as complex entities which create patterns as a result of finite local processes results in an exciting new age for landscape ecology and ecology as a whole. Landscape ecology seems to be rushing forward towards a multidisciplinary field in which the tools to answer questions as well as discover questions never asked may be possible. Perhaps it may at least be possible to separate the knowable unknown from the truly unknown, as Levin (2002) eloquently said in reference to the development of statistical mechanisms. The daunting introduction of complex mathematical notions to practitioners more comfortable in the physical world should be mollified by the exciting possibilities that the coalition of fields creates.

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