Development of a Carrying Capacity Assessment Model for the Australian Socio-Environmental Context
* PhD Thesis: The development of a carrying capacity assessment model for the Australian socioenvironmental context (Research PhD). By Murray Lane. A THESIS SUBMITTED TO THE FACULTY OF SCIENCE AND ENGINEERING OF QUEENSLAND UNIVERSITY OF TECHNOLOGY, 2014
"There are clear signs that society is threatening the biophysical limits of our shared environment and that the size, distribution and behaviour of the population is to blame. The ongoing worsening of crises like water, food, soil and energy depletion, climate change, biodiversity loss and environmental degradation serves to illustrate that the current human situation is not sustainable. The seven billion-strong global human throng is exerting such pressure on our existing societal and environmental systems as to suggest a re-evaluation of existing approaches to the way in which land and resources are managed and to the very structures that allow these problems to escalate. A whole-of-system approach would see a realignment of priorities whereby the economy is viewed as a subsystem of society and the environment provides the backdrop to all societal systems. In order to achieve a sustainable socioenvironmental balance, society’s resources will increasingly need to be produced and accounted for, much closer to where they are to be used. New societal strategies need to be developed in order to cope with the challenges ahead and a re-localised system of resource usage is one potential systemic change that may facilitate more sustainable future lifestyles. Carrying capacity assessment provides one important tool for estimating the ability of landscapes to support the demands of local populations. Carrying capacity assessment offers a way to assess our resource needs and also determine how best to meet these needs in the future. This process establishes direct causal relationships between a specific landscape, timeframe and people, and inherently links these aspects to systems of land usage and social function.
A key aim of this research is to highlight how society’s understanding of constraints to the productive capacity of its resource base is vital to its long-term survival. This was achieved through the development of an online model, the Carrying Capacity Dashboard, which links a population to the potential biophysical capacity of its environment.
By accessing and reconfiguring existing data, this research has developed a flexible, robust and easily-accessible carrying capacity assessment tool. It offers user choices relating to climate, diet, land-use, agricultural techniques, energy consumption and nature conservation, and also provides dynamic responses to online users. This educative feature is a valuable innovation to carrying capacity modelling which can assist in future societal decision-making processes relating to consumption patterns, land-use planning, population control and systems design.
Analysis developed from the Dashboard tests the effects of various resource consumption patterns on carrying capacity and highlights the degree to which various regions are over or under capacity. Three scales of analysis were employed – national, state and regional; and it was found that the most significant determinant of carrying capacity is the proportion of cropping land within any one state or region. Findings also reveal that Australia’s current short-term carrying capacity is estimated to be over 40 million. However, if calculated on a regional basis, the nation’s carrying capacity is reduced by almost half, suggesting that national resource utilisation would currently be more efficient than at the regional scale, even though future resource constraints may necessitate greater regional self-sufficiency. Longterm projections were also tested and carrying capacities both at a large and smallscale were found to be much smaller in a future fossil-fuel depleted context. Ultimately, this research indicates that an entire systemic change is required to place society back on the path towards sustainability. Such changes entail a future decentralisation of the population, agricultural and recycling practices instituted at local or regional scales and a rapid reduction in the reliance on non-renewable resources."
The Tokugawan Period in Japan as exemplifying ecological and population stability
"Japan’s Tokugawan period, between 1600 and 1868, was one of relative peace, prosperity and strikingly unusual population stability. From a carrying capacity perspective, this period highlights one potential ideal; reflecting a societal system that was both resource self-sufficient and well aware of its population limits. In this regard, Japan’s Tokugawan era provides a rare example of a population not only stabilised within the carrying capacity of its landscape but also conscious of the extent of these limits and dedicated to the difficult task of maintaining population numbers within such constraints.
The Tokugawan or Edo era began when Tokugawa Ieyasu took control of Japan in 1600 after a long period of internal conflict.213 While the first century of this era featured a rise in the Japanese population from about 20 million to 30 million people, the next 150 years is marked by very little change in population numbers214 until the Meiji Restoration after 1868 ushered in an escalation in population which today stands at over 120 million.
There is little doubt that the population stability evident during the Tokugawan era did not occur by chance, nor did it occur through Malthusian checks. Indeed, this period is noted for its prosperity rather than any deprivation. Rather, at a household level, the Japanese population was acutely aware of the optimum size and configuration of family makeup and took various steps to control it. Smith proposes that population control occurred through a series of initiatives such as, “low registered fertility and mortality, wide spacing of births, early stopping of childbearing by married women, and small completed families.” Smith examined one particular Japanese village in order to illustrate Tokugawan population dynamics and found that while abortion and contraception may have occurred, the practice which most significantly influenced family planning was infanticide. He argues that infanticide was used to control the gender sequence, the spacing of births and the overall size of families and that it was practiced by both large wealthy land-holders and poor tenant farmers alike.220 Given the stability in population numbers during this period, it can be assumed that families merely replicated existing numbers. According to Hanly and Yamamura, “[p]arents sought to rear a family of about three to four children.” Exact replication would suggest a family with only two children, but the additional one or two children suggested here may be accounted for by either premature death or childless adults. The optimum composition of Tokugawan families was also consciously regulated and according to Smith, the over-riding motivation was socioculturally based. He states that all families wanted one or two male children to supply a male heir and also to provide farm labour. However, any more than one or two males risked eventual competition over inheritance rights so female offspring were often deemed more desirable once the males were born.
While providing a salient historical exemplar of population control and stasis, to be relevant to the processes of carrying capacity assessment, the Tokugawan experience need also to provide evidence of a societal awareness of the landscape’s bio-physical limits and a commitment by the population to live within them. Evidence to support this notion is clear, but circumstantial. While there are no apparent records of villages or families stating that they restricted the population size to the biophysical limits, there is ample evidence that villagers were well aware of such limits, suggesting, as Macfarlane222 says, “an attempt to balance fertility and resources.” The way in which widespread awareness of resource production can be ascertained is through examination of the Tokugawan taxation system. At the beginning of this period, an assessment, called the kokudaka, was made of the productive capability of every Japanese village, with the resultant data being used to tax each village in the rice and other grains that were produced. According to Smith,223 these land registers aimed to, “register within a small and more or less carefully defined area - usually a village - each taxable field; to record the name of its holder, its extent, the quality of its soil, and its estimated yield… The kokudaka therefore was an estimate of normal yield with adjustments for factors affecting taxable capacity.” These records were openly assessable to all villagers, were updated throughout the Tokugawan period224 and formed the basis of their communal civic contributions. While they were designed for taxation rather than carrying capacity objectives, the result was the same – each Japanese family was acutely aware of the productive capacity of their farm and village, at a scale within which the vast majority of their resources were drawn. This high degree of self-sufficiency makes an examination of Tokugawan Japan even more relevant for carrying capacity-based exemplars. Not only was the nation as a whole relatively cut off from the rest of the world, but as Smith225 notes, each village was made up of mutually dependent families which, “attained a degree of self-sufficiency that was impossible for any of its members alone - a self-sufficiency imposed by physical isolation and the rudimentary state of the market.”
Another salient point in the exploration of the relevance of carrying capacity issues to the Tokugawan exemplar is the fact that Japan was effectively at or just below full population capacity by about 1700 when the population stabilised. As highlighted by Macfarlane,226 “there was also no open frontier for the Japanese,” they were forced into a choice between population stability or population overshoot, and all evidence suggests that they chose the former. One example of resource constraints limiting population size occurred in a village in Totomi Province where population records show that there were two types of local families; the ones in place prior to 1741 and those arriving after this date. As Smith227 explains, “[t]his particular date is significant since no new land was brought under cultivation after that. This year the absolute limit on the expansion of arable was apparently reached. Families founded afterwards, therefore, had access to land only as tenants, and they were probably placed under political disabilities to discourage any further increase in their number.” The example offered by Tokugawan Japan fulfils the criteria of a carrying capacity-led population dynamic. At a village level, this society was relatively selfsufficient; it was well aware of the productive potential of its landscape and it went to great lengths to maintain a population size within these biophysical limits. Far from being repressive, dreary or repugnant, this era is celebrated for its peacefulness and prosperity. Despite a stable population, there were quite significant changes and advancements in technologies and demography. As Smith228 explains, “the very success of the Tokugawan system created conditions favourable to change; cities grew, communications improved, productivity in agriculture increased, industry spread from town to countryside.” (https://eprints.qut.edu.au/67485/1/Murray_Lane_Thesis.pdf)