Fig. 5. Influential events and drivers in the history and policy of natural resources relating to agriculture.

Characterization of the system

Part of problem formulation is the dynamic characterization of the problem, that is, as a pattern of behavior over time. This is done through a set of reference modes and other descriptive data that show how the problem arose and how it might evolve in the future (Sterman 2001). In this study, we selected five variables, consistent with the “Rule of Hand” (Holling et al. 2000) and the first of four provisional propositions (Table 1) about SESs (Gunderson et al. 2002b) that, we propose, characterize the problem dynamically. They were selected from the ecological, economic, and social systems, and are (1) the area of productive land, (2) the number of agricultural establishments, (3) farmer age, (4) farmer terms of trade, and (5) the wheat yield. In systems analysis, it is the structure of the variables that gives rise to the behavior of the system.

Ecological reference modes of system behavior dynamics of land use

The conceptual model of the dynamics of land-use change patterns is shown in Fig. 6. The land-use system in the WA agricultural region can be classified into six major land-use types:

Fig. 6. A conceptual model of land-use change patterns in the Western Australia (WA) agricultural region. The return of land to secondary native vegetation in WA is under investigation.

(1)

primary native vegetation: natural native vegetation at or near climax, or regenerating by natural stages of succession;

(2)

cropland: cultivated and planted annually with food crops;

(3)

pastureland: covered with grasses, legumes, or herbaceous species for grazing livestock;

(4)

commercial plantation: land deliberately planted and maintained in tree monoculture and often in exotic species;

(5)

secondary native vegetation or regrowth: land cleared in large areas (often former crop or pasture land) left to natural succession, usually sufficiently degraded not to return to primary native vegetation (in the WA agricultural region the rates of return are unknown); and

(6)

unproductive land: land that has been so degraded that it produces virtually no useful species. Usually supports very little growth and will not return naturally to categories 1 or 5.

The predominant progression in the WA agricultural region is from primary native vegetation to productive broadacre agricultural system. Although persistent as an intensive agricultural system for more than 100 years, the land use has been dynamic. From a landscape dominated by native vegetation in the late 19th century, it became virtually treeless by the 1990s. The history of the dynamics of land-use change is illustrated by classifying and identifying the temporal patterns of land-use change between 1900 and 2000 and predicted changes to 2050 (Fig. 7). The greatest rates of clearing (Fig. 8) occurred in three phases, the first from 1900 to 1930 (144 000 hectares per year), the second from 1949 to 1969 (364 000 hectares per year) and the third from 1969 to 1994 (164 000 hectares per year) (Burvill 1979, Beeston et al. 1994). In the WA agricultural region, significant areas of non-productive land, due to inundation and soil salinity, appeared within 100 years of the first major phase of land clearing for agriculture. Sixteen percent of the area had developed soil salinity by 2000 and is now largely unproductive (National Land and Water Resources Audit 2001). One very important point is the time delay between the direct cause, land clearing, and the effects, inundation and the appearance of soil salinity, a slowly emerging ecological variable. Temporal separation between cause and effect often contributes to the intractable nature of problems (Meadows 1982). Recently, some land-use change from cropland to commercial forestry has occurred, in part to combat the hydrological imbalance. However, this represents a very small proportion of the total land area and occurs mostly in areas with rainfall greater than 600 mm; it will have no positive effects for large areas that are or will become salt affected. In 2000, the Environmental Protection Authority (EPA) took a strong position with a presumption against land clearing in the southwest of Western Australia for agricultural purposes and, in recent years, most applications referred to the EPA by the Commissioner of Soil Conservation have been denied.

Fig. 7. Changes in land-use in the Western Australia (WA) agricultural region, 1900–2050. (Sources:* 1900–1994 Beeston et al. (1994) and Burvill (1979); ^ Predicted 2000–2030 Government of Western Australia 1996).

Fig. 8. Rates of clearing land in the Western Australia (WA) agricultural region, 1890–2000. (Sources: Burvill (1979), Beeston et al. (1994)).

The condition of remaining native vegetation will continue to decline due to other effects including salinity, grazing and pest invasions and many more trees will eventually be lost from the landscape (Saunders et al. 2003). The line for the percentage of land use that is unproductive is based on values for agricultural land at risk from salinity in 2000 and the predictions of the extent of salinity (33%) in 2050 and 2300 are based on groundwater trends and “best guess” future land use (Hatton 2003, Hodgson et al. 2003). Hydrological equilibrium is predicted to be achieved between 2030 to 2050 in some areas on the western edge of the agricultural region but may take as long as 300 years in the eastern parts of the region (Hodgson et al., unpublished). The prediction of the amount of land that will become unproductive (33%) is based solely on the effects of salinity and does not include any other forms of land-degrading processes that may partially reduce soil fertility, such as acidification, sodicity, and erosion (National Land and Water Resources Audit 2002). To place this rate of change in the global context, one estimate of the total conversion of primary native vegetation to cropland worldwide was 10.7 million km², of which 20% was subsequently abandoned (Lambin et al. 2001).

Social-economic reference modes of system behavior

The socio-economic variables used in this conceptual model of the WA agricultural region were wheat yield, farmer terms of trade, and the number of agricultural establishments between 1900 and 2000 (Fig. 9 a, b, and c, respectively). Farmer age is also discussed in the text.

Fig. 9. Social and economic reference modes: (a) Trends in wheat yields in Australia and Western Australia between 1900–1994 (sources: Hamblin and Kyneur (1993), Passioura (2002)). (b) Trend in Australian farmer terms of trade between 1960–2000. Farmer terms of trade: the ratio of the index of prices received by farmers to the index of prices paid by farmers. Reference year 1997–1998 =100 (source: National Land and Water Resource Audit 2002). (c) Trend in the number of agricultural establishments in Western Australia agricultural region between 1900–2000 (sources: 1900–1976 Burvill (1979), 1977–1994 Australian Bureau of Statistics (1979–1997), 1995–2000 ABARE (2002)).

Wheat yield (economic production target)

Since the 1960s, farmers have faced constantly increasing costs and declining terms of trade, countered by increased productivity and efficiencies in recent times. Increases in crop production since 1960 have come from increases in yield (National Land and Water Resources Audit 2002). The trends for wheat yield for Australia and Western Australia between 1900 and 2000 (Hamblin and Kyneur 1993, Passioura 2002) are shown in Fig. 9a. The productivity gains for Australia occurred in three phases, 1900, 1950, and 1990, the greatest gains being achieved since 1990 (Passioura 2002). The significance of the increasing wheat yield is that it must be viewed against the economic background. If farmers are to continue to grow wheat, productivity must increase at a sufficient rate to counter the combined effects of declining terms of trade, the short-term fluctuations of climate, and world commodity prices. It was reported that Australia had the lowest rate of increase in wheat yield between 1950 and 1990 compared with its competitors in the world market (Hamblin and Kyneur 1993). The profitability of Australian agriculture, with its orientation towards export trade, remains closely linked to price fluctuations in international markets (Australian Greenhouse Office 2000). The trend of increasing wheat yield whilst achieving productivity targets under conditions of command and control policy masked other social and ecosystem variables that indicated a system in a state of change.

Agricultural terms of trade

Declining agricultural terms of trade (Fig. 9b) (falling prices of agricultural commodities compared with the price of farm inputs) have made it increasingly difficult for small and marginal enterprises to maintain their livelihoods solely by engaging in agricultural activities. Large numbers of farmers in broadacre agriculture in Australia had a zero or negative profit at full equity on the basis of a 5-year average to 1996–1997 (National Land and Water Resources Audit 2002). With no profit, there is little opportunity to adopt sustainable land practices that may include land-use change, and may be potentially risky and costly to adopt in the short term (Cary et al. 2002). Clearing is motivated by the pursuit of agricultural profit, either for immediate returns or for future gains through improved land values (Burvill 1979, Australian Greenhouse Office 2000), and is a practice considered to be one of the greatest natural resource threats in Australia.

The number of farm establishments and farmer median age

The number of farms in the WA agricultural region rose to a maximum of approximately 23 000 in 1968 (Fig. 9c). Since then, this number has been declining. It dropped to approximately 9 000 in 2000. Although the lifestyle of some farmers with small enterprises became less economically viable, farm adjustments and restructuring did not always follow the neo-classical course of farm exits and property amalgamation (Barr 2000), and the decisions are classed as being boundedly rational (Walker et al. 2002), made with imperfect knowledge and context specific. On many farms, the main adjustment was abandoning the expectation of intergenerational transfer; coupled with this, there was a deferral of farm exit in response to a perceived lack of alternatives available to broadacre operators. Consequently, the number of older farmers increased. In Western Australia, the mean age of farmers increased from 48 to 52 years between 1990 and 2000 (ABARE 2002). A similar trend was also recorded for changes in farmer age throughout Australia (Barr 2000). Barr (2000) contends that there will be a major restructuring of farming enterprises caused by the unsustainable rise in farmer age as older farmers exit the industry.

The reference modes show an increasing area of unproductive land, declining terms of trade, rapidly declining number of farm establishments and an increasing average age of farmers over time. Although the wheat yield is increasing, this increase is not as strong as in other countries that compete in the global marketplace. These features were found to be common characteristics of commodity systems (Sawin et al. 2003) and are considered to be examples of diminished sources of novelty, which increase vulnerability of the system, the fourth provisional proposition about SESs (Table 1). The reference modes, together with the historical account, were used to identify the adaptive cycles in the region, described below.

The events or practices that characterized the different phases of the adaptive cycles are summarized in Table 7. The management history of the region between 1889 and 2003 can be described by two iterations of the adaptive cycle, the first occurring over the 60 years between 1889 and 1949, and the second over the 63+ years between 1949 and 2003.

First cycle

For the first 60 years of the Western Australia colony's history, pastoral activities were developed ahead of agriculture; only 28 000 ha were developed for cropping by the 1880s. In the period labeled the “Move Forward,” Western Australia government policy drove development; railways were initially constructed along valley floors and, consequently, the land adjacent to the railways was cleared for agriculture first (Frost and Burnside 2001). Government institutions, such as the proclamation of the Homesteads Act (1893) and the Land Act (1898) that set out the concessions and conditions for obtaining farmland, enabled land-use planning and accelerated land release for agriculture. By the late 1920s, 50% of the area now identified as the WA agricultural region was cleared of native vegetation. Prices for both wool and sheep were high. The features of this period are characteristic of the forward loop (r-K) of the adaptive cycle. In the adaptive cycle, this is explained by an increase in the capacity or potential for change and an increase in the degree of connectivity among the variables (Table 2). However, variables may become over-connected, reducing resilience, and the cycle moves into the backloop. The 16-year period between the Great Depression of the 1930s and WWII was marked by hardship in agriculture, with low potential for change and low resilience. Record low prices for wool and wheat and dry climatic conditions caused farms to be abandoned, producing conditions in which novelty could occur. Recovery began in 1945, major advances in technological and scientific innovation occurred, and there was also institutional change, such as farm amalgamation to make farm sizes more viable. The internal structure was low, which allowed the potential for change to increase. The resilience to external disturbance was also greater at that time. This completed one iteration of the adaptive cycle (Table 7).

Second cycle

The second iteration and the frontloop of the adaptive cycle began with the Post-war (WWII) Boom. Fuel was cheap and abundant, labor was also abundant, and these factors combined with favorable climatic conditions and a development-orientated Government to produce a rapid expansion of agricultural lands. The rate of clearing increased from 36 000 ha a year between 1930 and 1949 to 364 000 ha a year between 1949 and 1969 (Fig. 8), which increased the area of cleared land from approximately 50 to 90% of the region. The major commodities experienced high prices in the 1960s (Burvill 1979, Hamblin and Kyneur 1993), resulting in overproduction on the global market of wool and wheat. This period is represented by the exploitation to conservation phases (r to K) of the adaptive cycle. There followed a “Troubled Decade,” marking the beginning of the backloop of the adaptive cycle with the release phase, in which the Australian Government introduced quotas to regulate the production of wheat, and prices fell. Land degradation was perceived as a greater problem and there was a drier than average period. From 1980 onward, there was massive change and reorganization in institutions at the regional level, marking the beginning of the reorganization phase and continuing the backloop through to the present. Two marked examples of institutional change are the unprecedented alliance of the Australian Conservation Foundation and the National Farmers Foundation, who joined together to try to combat the growing problem of salinity. The need to allocate lands for conservation was also recognized at this time and was implemented through the Conservation Through Reserves Program. In the 1990s, further institutional reorganization occurred through the construction of partnerships across scales in government from regional natural resource groups to state and national organizations. In 2003, institution restructure continues, including the development of policy that incorporates economic solutions for NRM. Increasingly, market-based mechanisms and creation of property rights for ecosystem services are being promoted for NRM policy (National Action Plan for Salinity and Water Quality 2002a).

Lock-in Trap

The WA agricultural region is an ecological system whose species mix has been transformed for commodity production. The area of original native vegetation was reduced to less than 10% of its original extent. Hydrological modelling (Hodgson et al., unpublished) predicts the continuing loss of area of native vegetation, further reducing biodiversity. The ecosystem has been transformed from a species-rich system to a specialized system with low species richness and loss of system function. There are high costs to maintain productivity function and ecosystem function. For example, agriculture supports an extensive industry to maintain productivity, including the costs of fertilizers, new wheat varieties, and agronomy to mitigate soil degradation including acidification and soil erosion, drainage, and revegetation (Passioura 2002). An extreme example of the costs of maintaining ecosystem function is provided by Toolibin Lake and its catchment in the WA agricultural region (Toolibin Lake Recovery Team and Toolibin Lake Technical Advisory Group 1994). In 1990, the lake was listed as a wetland of international importance under the Ramsar Convention and was selected as a Natural Diversity Recovery Catchment in 1996. Both increasingly saline surface water inflows and rising saline groundwater seriously threaten the biodiversity values and the ecosystem function of the lake. The protection of these functions requires a complex integrated management strategy comprising a number of actions, including changing agronomy practices in the catchment, surface water management, and increasing groundwater discharge with groundwater pumping to lower the watertable below the lake (Wallace 2003). The WA agricultural region has lost important system components involved with the hydrological cycle and the system has been irreversibly modified.

The reference modes portray the WA agricultural region as a system with resource depletion, environmental pollution, and social decline. Could we conceive that the WA agricultural region is in a poverty trap or alternatively in one of the other pathological states? Holling et al. (2002c) proposed that an adaptive cycle will cease to be adaptive because the potential and diversity have been eradicated by misuse or an external force, and they use as an example the degradation of savannas that enters an irreversible eroding state (Holling and Gunderson 2002). Human activity such as agriculture may “mine” the resource (for example, soil (Passioura 1999)) in a lock-in situation, in which the land manager is under greater and greater pressure to produce more, while the economic return from the land diminishes, either because of lowered productivity, reduced terms of trade, or both. Ultimately, the ecological system will become severely impoverished as the variables and players in the commodity system become more tightly connected, causing the resilience to increase because the system has reached such a depauperate state that it is extremely stable. Greater connectivity emerges from complex systems of relationship and dependence between producers and the agro-industry they support. This situation is represented by one of the remaining two unaccounted pathological states. This state we have labeled “lock-in” which, in economics, describes an industry that has so much “sunk-costs” that it may continue to degrade the resource it relies upon until the capital is totally removed. The lock-in pathological state has low potential for change, high connectivity, and high resilience. High resilience would mean a great ability for the system to resist external disturbances and persist due to the depauperate ecological system.

Scale and dynamics

The duration of each of the two cycles described above is synchronous with the third and the fourth long-wave economic Kondratiev cycles. The upwaves of the Kondratiev cycles shown in Table 5 are in the order of 50–60% of the total duration of the cycle, and this is consistent with the duration of the forward loop in the two adaptive cycles that describe the behavior of the WA agricultural region. The model for the adaptive cycle heuristic was developed for biological systems in which the characteristics for biological processes may be described by means of a slow build-up of resources in the frontloop in the order of 75% of the total time, as suggested by Walker (2002), or capital that can be lost in one catastrophic event. However, the driving variables in the WA agricultural region were the long-wave economic cycles that do not conform to the organismic model of long, slow accumulation of capital and comprise between 40–60% of the total cycle time.

Macroeconomics and technological development were the prime drivers behind clearing native vegetation in the development of agricultural land in Western Australia, as promoted and sanctioned by government policy. The duration and structure of the two cycles in the WA agricultural region, with an area of 14 million ha (Legislative Assembly Western Australia 1990), is inconsistent with those found for the Goulburn Broken Catchment (Walker et al. 2002) with an area of 2.4 million ha (Goulburn Broken Catchment Management Authority 2002). In a resilience analysis of the dynamics of the Goulburn Broken Catchment in Victoria, Australia, stakeholders identified an historical profile of major events and developments in the catchment (Walker et al. 2002). These factors were, in general, socio-economic; from them, Walker et al. (2002) identified four periods of major changes over 150 years (1750–2000) and suggested that a general pattern, where 75% of time is spent in the forward loop (exploitation to conservation phases, with slow accumulation of capital), may be typical for regional systems. However, this finding of Walker et al. (2002) is inconsistent with the pattern found in the WA agricultural region in which, over its 114-year history, only 66 and 48% of the time was spent in the forward loop or the upwave of the Kondratiev cycle, respectively. One possible explanation for the temporal differences is the difference in spatial scales of the two regions which may have resulted in a greater influence of more local events in the Goulburn Broken region; for example, the influence of the depression of the 1890s before the significant agricultural development in Western Australia, regional drought and dust storms, and poor success of stone fruit, for example. The regions also differ markedly in biophysical characteristics. On first appearance, although not directly comparable, the durations of the adaptive cycles between the WA agricultural region and the Goulburn Broken Catchment may appear inconsistent, but the authors believe that further detailed analyses and additional case studies would be beneficial and add strength to the argument.

Thresholds, stability, and resilience

A key aim of resilience analysis (Walker et al. 2002) is to identify thresholds, their nature, and what determines how they prevent the system from moving into an undesirable system configuration. Ecosystems of renewable resources threatened by the interactions of economic and social systems may lose resilience (i.e., the ability to absorb shocks and disturbances) and may suddenly break down or settle into a different system with less resilience (Gunderson and Holling 2002). This implies that there are thresholds at which the levels of stress will lead to the disruption of the system, the first of the six assumptions ascribed to complex systems (Walker et al. 2002).

The ecological buffering that helps a system cope with surprise (Folke et al. 2002) has been lost from the WA agricultural system, that is its resilience, the tendency of a system to remain unchanged, or nearly unchanged, when exposed to perturbation (Hansson and Helgesson 2003). For example, loss of perennial vegetation and consequent elevation in watertables saturates the subsoil, reducing its ability to absorb further rainfall and its buffering capacity, particularly under conditions of greater than average rainfall. Often a system can be stabilized by increasing the size of a buffer (Meadows 1970) but, like the hydrological system, it is a physical entity the size of which cannot be changed. As a result, flood events have occurred, such as was experienced in the Moore River catchment in the northern area of the WA agricultural region in 1999 (Water Studies Pty Ltd 2000) and in the Avon River catchment in 2000 (Hatton and Ruprecht 2001). In addition, the predicted changes in annual total rainfall and distribution for the southwest of Western Australia, in the form of extreme events, as a consequence of global climate change (CSIRO 2001) may create periodic crises that could have an overwhelming impact on the SES. When there is little or no ecological buffering capacity, or it has been exceeded, the control shifts to regional economic, demographic, or social factors. The potential impact could be a retraction of the area under annual cropping, with areas being abandoned or a threshold being reached in the number of farmers, as hypothesized as a major restructuring of the rural demographics by Barr (2000), with enterprises at the margins exiting the agricultural industry.

Agricultural intensification was a major feature of the second adaptive cycle. It was agricultural intensification involving changes in technology that largely masked the degradation of natural resources and helped to produce the perceived stability in the system. Novelty in technology effectively redefined the system and thus prevented the whole system from crossing critical thresholds and changing from one stable state to another. Even with the ability to redefine the system by creating novel futures through technological advances, this system will still rely on a continuous stream of new technologies, institutions, or social adaptations to add resilience and maintain the adaptive capacity of the whole system.

Technological advances make single variable interventions or create interventions without regard for their impacts on other parts of the systems. This has been described as human propensity to focus on “single cause-and-effect solutions” (means–ends logic designed to solve a particular problem) (Westley et al. 2002), and this has serious implications for continuing resource misuse. For instance, as a solution is found for each problem, it will create other effects, referred to as side effects or perverse and unintended effects. In economics, side effects are often called externalities and an important component of ecological economics is estimating the value of these externalities (Costanza et al. 1997). The creation of new institutions (e.g., policies and markets) is being promoted in Australia as one way to help to account for the full costs to society of NRM (Agriculture, Fisheries and Forestry - Australia 2001, National Action Plan for Salinity and Water Quality 2002a).

Policy responses

In the WA agricultural region, we have shown that the time-dependent nature of the problems in economic–ecological systems, feedback concepts in systems theory, the transformations in interrelated human and natural systems, and mismatches of scale between human responsibility and natural interactions have contributed to a Lock-in Trap. An example is the effects of clearing land, which were known in the early 1900s but not treated seriously until the 1990s. Reactive policy and command and control management in response to crises has dominated the WA agricultural region, each new policy responding to the effects (side effects or unintended effects) of the past policy. This is a well-known phenomenon in system dynamics, “policy resistance” (Sterman 2001) that is also described as the bite-back paradox in large-scale systems (Gunderson et al. 2002c). A sequence of three types of NRM policy can be recognized over time in Western Australia (Allison and Hobbs, submitted). Command and control or regulatory policy was in place from the 1890s until the 1990s. The second policy approach was voluntary participatory policy encouraging partnerships of institutions at catchment, regional, state, and national levels. The third approach, now promoted at the national level, involves market-based mechanisms to manage natural resources (National Action Plan for Salinity and Water Quality 2002b) in response to a perceived lack of property rights, which is proposed as a cause of natural resource degradation. It is no longer reasonable to assume that environmental feedbacks are not a dynamic component of the economic system (O'Neill et al. 1998). This is not a new concept and many papers in the literature identify the link between the economic and the ecological system, for example Daly (1991).

When faced effects that are perceived as crises, management options fall into one of three general classes of response. The first is to do nothing and wait and see if the system will return to some acceptable state while sacrificing benefits of the desirable state. The second option is to actively manage the system and try to return it to a desirable stability domain. The third option is to admit that the system is irreversibly changed, and hence the only strategy is to adapt in a world characterized by crises and shifting stability domains. All three of the responses were seen sequentially in the WA agricultural region. The problem of soil salinity was known early in the history of the WA agricultural region and for economic, social and political reasons the Government chose to ignore the scientific advice and released land for agriculture in areas known to be susceptible to salinity and in areas known to be marginal for agriculture because of both climatic variability and poor soil characteristics. The second response was to put in place actions directed at fixing the symptom (the bite-back phenomenon), as opposed to actions to address the systemic causes of the problem. For instance, many tree planting programs designed to alter the changing hydrological patterns failed and advice on where and what to plant changed as our scientific understanding of the hydrological system improved.

The third and current response contains a number of strategic actions aimed at adapting to the current situation. One strategy of current policy is that of environmental triage, in which it is acknowledged that some areas will not be able to be managed positively and no further pubic funds will be directed to these areas. The second strategy is the introduction of market-based instruments. This is based on the premise that many of the changes including biodiversity loss are caused by inadequate institutions, in particular ill-defined property rights (Hanna and Munasinghe 1995) and the impact of this on resource use. The design of institutions such as property rights is a major thrust in Australia natural resource policy. Young and McCay (1995) argue that by adding flexibility and renewable structures to property right regimes they can be adapted to incorporate social and environmental objectives, and this is one way to increase resilience. However, the use of market-based instruments for NRM is in its infancy and further research is required to better understand the relationships between various property rights regimes and the dynamics of complex systems where the interactions between variables occur at different temporal and spatial scales.

Nonetheless an important research question would be “Are there times within the economic cycle that provide times of greater leverage for different types of policy?” In other words, is it possible to create policies that are most appropriate for the dynamics of the system; “Let the policy fit the time.” In the agricultural industry, times of rapid change and restructuring may be the most appropriate period to implement policies that create the greatest change to meet the desired objectives of society; for example retiring severely degraded land, allocating land for conservation of biodiversity and the maintenance of ecosystem services. This may be particularly relevant if there is a trend away from the family farm to the corporate far, which is able to adopt precision farming methods which can identify areas which give little return or incur a cost to the farmer (Passioura 2002). Such areas may be retired out of production and planted for biodiversity and ecosystem function benefits. Alternative policy approaches which have met with some success in achieve sustainable resource use, in specific circumstances, take the form of social institutions such as supply and production limits, certification for best practices, tax and payments based on stewardship that expand the goals of the natural resource economy to encompass more than the standard definition of efficiency (Sawin et al. 2003).

Natural resource problems are characterized by increasing complexity and unprecedented connectivity both within scales and across scales. Conventional environmental decision-making methods have been unsuccessful in resolving these problem situations because of our lack of understanding in certain areas of system science, discussed in the introduction. We proposed that the use of a number of different tools increased our understanding the problem situation, from an epistemological perspective.

In this paper we have made a diagnosis of the current situation of WA agricultural region by applying a systemic approach. We developed a conceptual model of how we perceive the problem situation. The conceptual model was composed of the history of the system, the reference modes that characterized the behavior of the system over time, and their interpretation with reference to long-wave economic cycles and the adaptive cycle. The development of the history was the first important step in an examination of the SES but histories tend to be static and event orientated. However, we overcame this static interpretation by constructing reference modes and interpreting the behaviour through the use of the adaptive cycle metaphor and the Kondratiev cycles. Our conclusion was that the two adaptive cycles described in the WA agricultural region were synchronized with the 3rd and 4th Kondratiev cycles. Because the Kondratiev Cycles are based only on economic and political behavior, the inclusion of resilience theory moves beyond the economic and political behavior of the system and requires causal explanations not only for the economic cycles but also for the ecological and social behavior of the system. The integration of these tools has shown not only the dominance of the long-wave economic cycle in the WA agricultural region but also how the economic cycles composed of fast moving variables have been largely decoupled from the slow moving ecological variables.

We suggest that the current state of the WA agricultural region is the balance between those processes that erode resilience and those processes that have maintained it through the expansion of the thresholds. The continuing degradation of natural resources shown by the reference modes is a syndrome that involves the breakdown of several resilience mechanisms. The changes in land-use and the ensuing natural resource degradation are rooted in economic, demographic and social changes that link the variables in the ecological system to those in the social system. We showed that resilience in the WA agricultural region was derived from functional reinforcement across and within scales, and the adaptive capacity from across systems through interaction between the social-economic system and the ecological system. We claim that the driving forces in the dynamics of the WA agricultural region were macroeconomics mediated to some extent by institutional factors such as government policy and markets.

Through the application of the metaphor of the adaptive cycle, Holling et al. (2002a) proposed that ecological collapses and the subsequent need to innovate, create, reorganize, and rebuild, are inevitable consequences of human interactions with nature. The WA agricultural region exhibits the common pattern of westernized commodity systems in which the stabilization of the agro-ecosystem (one system) has led to the progressive decline of the whole system. The adaptive cycle metaphor is applicable to the WA agricultural region, has shown the sequential progression between the phases that maximize production and accumulation and the phases that maximize invention and reassortment in the socio-economic system. We propose that successive cycles in the socio-economic system will continue to impact on the slow ecological variables reducing the potential or capital through time. However, we might ask the question “Is it possible for the system to escape the Lock-in Trap?” For this we have to make further inferences from resilience theory.

The application of proximate drivers (policy instruments) aimed at the mitigation of any or all of the three symptoms of the commodity system may produce short-term changes. However, as described above, policy resistance will most likely occur. In contrast, for systemic change to occur, Gallopin (2002) suggests that three pillars of decision making, willingness, capacity and understanding, must be applied. Any change in these three areas will require the application of ultimate drivers that shape the fundamental structure of values, knowledge and empowerment.

Using the metaphor of the adaptive cycle, the Lock-in Trap is characterized by low potential for change, high degree of connectedness among the structural variables and, because of the extremely degraded state, a high resilience to change. The system has become vulnerable as sources of novelty have been eliminated and as functional diversity and cross-scale functional replication are reduced. This suggests that the forces of the commodity system will continue to produce the three symptoms, the erosion of the resource base, increasing environmental pollution and continuing social decline within the region, all else being equal.

Responses to this article are invited. If accepted for publication, your response will be hyperlinked to the article. To submit a comment, follow this link. To read comments already accepted, follow this link.

The corresponding author is grateful for financial support from a Murdoch University Research Scholarship. The authors are grateful to anonymous reviewers for the constructive comments. Thanks to Frank Murray for his comments on the manuscript. Thanks also to Donald Burnside, Charlie Nicholson and Bryan Jenkins for many stimulating discussions on NRM that have contributed to this paper. We are also grateful for the technical support of Kevin Hardman and Alan Rossow for drawing some of the figures. We are grateful to Island Press for granting permission to use elements of Figure 3-12 from Holling, C. S., L. H. Gunderson and G. D. Peterson. Chapter 3, Sustainability and panarchies from Panarchy: Understanding Transformations in Human and Natural Systems, L. H. Gunderson and C. S. Holling, eds. Copyright ( 2001 by Island Press. Reprinted by permission of Island Press, Washington, D. C., and Covelo, California, USA.

In the history of Western Australia, agriculture and natural resource policies were reactive, in response to reports about the declining condition of soil, land, or water. Figure 5 presents a chronological sequence of those factors considered to be the most significant and influential in either changing the direction of policy or identifying the direction of change. Soil erosion was the first category of natural resource degradation to attract legislation directed at its mitigation, namely the Sand Drift Act (Western Australia) 1889.

In 1916, a Royal Commission was appointed to review agriculture (Royal Commission on the Agricultural Industries of Western Australia 1917) and the mallee lands in the southeast of Western Australia (Royal Commission on the Agricultural Industries of Western Australia 1918). Following this review, a map was prepared defining the area considered to be the safe rainfall limit for wheat. This line became known as the Brockman Line after the Surveyor-General F.S. Brockman; it is shown in Fig. 1 (Burvill 1979). Even then, agriculture extended beyond this line, raising concern about the long-term viability of agriculture in these areas. Soil salinity was already apparent in the mallee region but was discounted as a concern in the report of 1918 (Royal Commission on the Agricultural Industries of Western Australia 1918). However, within another 10 years, soil salinity was again presenting as a problem in certain soil types.

The dust bowl in the USA in the 1930s and widespread wind and water erosion in Australia led to a revived interest in soil conservation as a national concern. During the years of the Depression and the War (WWII), the federal Soil Conservation Act 1938 and, in Western Australia, the Soil Conservation Act (Western Australia) 1945 were enacted in direct response to the extent of the problem. They were soon followed by the establishment of the federal Standing Committee on Soil Conservation in 1946. During this period, a combination of social, economic, and ecological factors caused many farmers to declare bankruptcy and abandon their farms (Burvill 1979). Wheat prices dropped from $23 (AUD) to $8 (AUD) per ton in the early 1930s. Simultaneously, the wool price dropped, removing the opportunity for farmers to move between the production of these two commodities, which was common practice in the ley-farming method. The rate of clearing dropped by about 75%, from 143 750 ha a year before 1929 to 36 789 ha a year between 1930 and 1945 (Fig. 6).

In stark contrast to the poor conditions (economic, environmental, and technical) in the period labeled the Depression and the War, the 20 years of the Rural Boom were the only period of untroubled prosperity (Frost and Burnside 2001). At this time, a combination of four key factors in the economic, social, ecological, and technological systems encouraged very high rates of clearing. These were: cheap fuel; increasing technology in the form of heavy machinery and the use of heavy chain to clear native vegetation; high wheat and wool prices; and government policy encouraging the clearing of 1 million acres per year. The prices for both wheat and wool escalated in the early 1950s, the period following WWII. In 1950–1951, wool was approximately ten times the value it was during the war and wheat reached five to eight times the value of crops in 1930 to 1944. As a result of these four factors, the rates of clearing increased by a factor of ten, doubling the area cleared from 6.48 million hectares in 1949 to 13.77 million hectares in 1969, to capitalize on the high commodity prices (Cary et al. 2002).

The Rural Boom was sustained by both ecological and technical factors. Favorable rains for a 10-year period between 1958 and 1968, combined with technological advances in fertilizers, operated to overcome soil deficiencies and encouraged the expansion of agriculture into areas with proportionately more second- and third-class soils. Third-class soils were classified as marginal and it was not expected that landholders would clear such land, although invariably they did (Australian Greenhouse Office 2000). Once the limiting factors of soil deficiencies had been overcome, climate rather than soil capability was, in most instances, the limiting factor in agricultural production. Expansion into areas with poorer soils and less reliable rainfall, beyond the Brockman Line (Fig. 1), laid the way for many future difficulties in the following decades, particularly in extended periods of dry climatic conditions. Technological innovations in other areas of the agricultural industry occurred, producing new chemicals for the control of pests and weeds, new crop varieties, and new farm machinery that together increased the intensity of agricultural production.

The Rural Boom from 1949 to 1969 produced record numbers of sheep and record quantities of wheat, causing an oversupply on world markets (Burvill 1979). In response, the Australian Government intervened by introducing wheat quotas in 1969, the beginning of the Troubled Decade. Wheat production dropped by one third between 1969 and 1972. In the late 1970s, new trends in agriculture emerged that were accompanied by new constraints. The general trend in agriculture was toward increased specialization, more technically complex and more intensive agriculture. The lack of infrastructure that had constrained agriculture in the past was replaced by the limitation of unreliability of the growing season due to annual rainfall variability, particularly in the newer, less favorable, areas developed after 1950 during the Rural Boom. Declining agricultural terms of trade (falling prices for agricultural commodities compared with the price of farm inputs) compounded the problem, making it increasingly difficult for small farmers to maintain their livelihoods solely by engaging in agricultural activities (Barr 2000). Large numbers of farmers left agriculture during the Troubled Decade. The number of agricultural establishments in Western Australia fell from approximately 23 000 to 17 800 between 1968 and 1976, the trend being mirrored throughout Australia (National Land and Water Resources Audit 2002).

In the Troubled Decade, soil conservation again began to emerge as a matter of national importance and concern, triggered by a rising conservationist ethos and increased land degradation caused by two decades of pro-development agricultural policies in the 1950s and 1960s. By the end of the 1970s, it was estimated that just over half of Australia's agricultural land was degraded (Department of Environment, Housing, and Community Development 1978).

In the 1980s, the environment became a political issue and, in 1988, the Australian Conservation Foundation and the National Farmers Federation engaged in a cooperative agreement to combat the problems of land degradation at the national policy level (Toyne and Farley 2000). The joint action of these two groups, which previously had taken opposing positions on land conservation policy, was an unprecedented effort to try to solve an intractable national-scale problem. As a consequence of this alliance and in collaboration with the Federal Government, the National Soil Conservation Strategy was released in 1989 aimed at mitigating land degradation.

As the environmental movement increased its pressure, the Federal Government declared the “Decade of Landcare”' initiative in the 1989 Statement on the Environment, under the National Landcare Program, a voluntary community participatory program supported by funding through the National Heritage Fund (see Fig. 5). During the Decade of Landcare, the rate of land clearing dropped from 188 000 ha per year between 1977 and 1994 to about 42 800 ha per year between 1994 and 2001. The Landcare Plan was an important strategy that helped inform and change the attitudes of many land managers in relation to the need to change current land management practices. However, a change to more sustainable land-use practices requires more than a change in attitude (Cary et al. 2002).

The Landcare Plan was criticized even by its originators (Toyne and Farley 2000) for its lack of strategic and co-ordinated action. The most recent coordinated regional approach comes under the National Action Plan for Salinity and Freshwater. The Western Australia Government signed a bilateral agreement with the Federal Government in 2002 (Government of Western Australia 2002) to initiate the National Action Plan in Western Australia, coordinated and delivered by the newly formed Natural Resource Management Council through the Western Australia State Natural Resource Policy (Government of Western Australia 2001).

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