As Our Common Future insisted in 1987, “Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” Since the Industrial Revolution, human development has accelerated so much that its sustainability has come into question. Here I would like to present my proposal for what we should do to make our civilization sustainable. There are three major problems, namely the restriction of population growth, the maintenance and restoration of vegetation, and the utilization of renewable energy.
1. Birth Control by Education
It is the vast expansion of energy consumption that has brought about the current destruction of the environment and exhaustion risk of the resources. Energy consumption increases after the Industrial Revolution and especially rapidly after the latter half of the 20th century, as the figure below indicates.
The amount of energy consumption is the product of multiplying population and energy consumption per capita. Which should we reduce?
Technological innovation can reduce energy consumption per capita without derogating the quality of life. It is also important to minimize the damage of the high-entropy waste that the consumption of energy emits to the environment. Undoubtedly, the innovation of energy and environmental technology is crucial. Technological innovation, however, becomes powerless to reduce total energy consumption, if the population continues to increase at the present rate. Population growth has a high correlation with total energy consumption, which has especially grown rapidly after the latter half of the 20th century, as the figure below indicates.
But, as we see in this chart, the growth rate of the world population has dropped since the 1960s with the declines in fertility.
What causes the declines? The total low fertility rate is conspicuous among advanced countries. Among the lowest are countries in East Asia and Europe, where parents are eager for their children’s education. Among the highest are African countries, where parents exploit children as laborers. Many children mean a high cost in advanced countries and a high income in developing countries. That is why the total fertility rate is low in advanced countries and high in developing countries.
In advanced societies that make much of an academic career, women marry late because of long-term education and bear fewer children. We can attribute the negative correlation between education and fertility rate to the fact that “as literacy improves, fertility rates tend to decrease.”
Education can sublimate sexuality up to science and art. Recent research shows that higher intelligence operates as a protective factor against early sexual activity during adolescence. In an advanced society where the information industry has developed, people can enjoy various amusements and an interest in real sex wanes. People will get interested in multiplying their memes in the virtual world rather than their genes in the actual world.
These various factors have brought the transition from a labor-intensive or capital-intensive economy to a knowledge-intensive economy. Lester C. Thurow calls this transformation of the economy “the third industrial revolution”.
In the third industrial revolution intellectual property rights are becoming more important as other sources of competitive advantage become less important.
To promote this trend, I propose introducing a Pigovian tax on childbirth. It might sound unpleasant because it is as if bearing a baby is like emission of a harmful substance. So, I propose calling it “upbringing insurance”.
Suppose parents must pay an insurance premium for childbirth, it will reduce the birth rate, because parents have to pay all costs to bring up their children and the government does not offer subsidies. The essence of the Pigovian tax is the internalization of externalities. Even if they get unable to bring up their children, insurance enables the children to receive enough education. In short, introducing this compulsory insurance has two effects, the reduction in birthrate and the elevation of the academic level of workers.
Although developing countries have produced poor-educated workers, these workers would be redundant in the future because of computerization and automatization. Simple work is no longer the work for humans but computers and robots. What will be important in the future labor market is not the quantity but the quality of labor.
The upbringing insurance will decrease population but increase excellent engineers because investment in education per capita increases. As I said at the beginning of this division, what is important to reduce total energy consumption is technological innovation and restriction of population growth. The increase in excellent engineers will promote technological innovation.
Some are afraid that the current decreasing fertility rate and mortality rate will stagnate the economy temporarily because the ratio of retiring-age population to working-age population will increase for a while. Here again, the transition to the knowledge-intensive economy can solve the problem. Human physical ability wanes as he or she ages, while aging does not so rapidly weaken human intellectual ability. The knowledge-intensive economy makes older but experienced workers useful.
2. Organic Agriculture
In order to meet the increasing demand for crops and livestock caused by the rapid population explosion after the Industrial Revolution, modern man has been clearing forests to create farmland and pastureland. The following figure depicts how the development of modern civilization has caused the disappearance of virgin forests in the United States.
The upper left figure, from 1620, shows the distribution of old-growth forests when the English Mayflower arrived in Plymouth. At that time, the eastern part of the Americas was covered with dense old-growth forests. Eventually, however, European immigrants eroded the old-growth forests, and today, very little remains. Although not depicted on this map, artificial forests are now increasing due to reforestation. In fact, the current forest cover is not even close to the level of 1620.
Desertification (soil degradation with little or no vegetation) is of course undesirable. Plants not only offer us food, fuel, materials for building, clothing, medicine, etc. but also coordinate water and temperature. To prevent desertification, we should abandon modern non-sustainable agricultural practices and restart the organic agriculture that we used to engage in.
The United States Department of Agriculture defines organic agriculture as a “concept and practice of agricultural production that focuses on production without the use of synthetic pesticides“. This definition is insufficient. Organic agriculture should not use any agrochemicals including herbicide and chemical fertilizer. Since it makes the most of useful bacteria such as mycorrhizal fungi, leguminous bacteria, crops need only a little manure. We should not manure too much, because excessive manure induces insects and pathogenic germs.
Organic agriculture makes our farming sustainable. Thanks to mycorrhizal fungi, crops can grow without pesticide and herbicide and with little manure and water. Moreover, mycorrhizal fungi absorb and store carbon underground. The New Farm that promotes “organic farming” lays stress on this function. According to the New Farm, organic matter can remain as stable carbon compounds for thousands of years in the ground.
Before forests and grasslands were converted to field agriculture, soil organic matter generally composed 6 to 10% of the soil mass, well over the 1 to 3% levels typical of today’s agricultural field systems. The conversion of natural grasslands and forests around the globe works to elevate atmospheric carbon dioxide levels significantly. Building soil organic matter by better nurturing our forest and agricultural lands can capture this excess atmospheric carbon dioxide, and preserve more natural landscapes.
Another important thing to stop desertification is to reduce livestock farming. Livestock farming is the major cause of desertification. We should eat the meat of aquatic animals instead of terrestrial animals and reduce our excrement to the land so that inorganic nutrients, especially phosphorus, circulate between the land and the sea.
You might be afraid that this change of animal protein source would exhaust marine resources, but the reduction in human population and retrieval of inorganic nutrients can prevent a drain on marine resources. Enriching the resources on the land enriches the resources in the sea.
As the wall of the Minoan palace at Knossos shows, the Mediterranean Sea used to be rich in marine resources. The deforestation and overgrazing enhanced by the Ancient Greek and Roman civilizations deteriorated the land and reduced the influx of inorganic nutrients, while they have remained at the bottom of the sea. Modern civilization is doing throughout the world on a large scale what the Greek and the Roman did around the Mediterranean Sea on a small scale in the Ancient.
Another concern about my proposal is the way to reduce human excrement (feces and urine) to a field. You cannot directly apply human excrement. Aerobic fermentation should decompose it into the water, carbon dioxide, and residual minerals that can be manure. Joseph Jenkins who advocates composting human excrement for agriculture named it “humanure”.
This disposal may appear quite filthy and unsanitary. But mixing human excrement with sawdust at a high temperature (over 50 degree Celsius) annihilates the pathogenic colon bacilli, parasitic insect eggs and so on and decompose it without emitting an offensive odor. A Japanese company has developed such a toilet named “Bio-Lux”that consumes no water, but the device requires no high technology. Everybody can easily make this dry toilet that produces humanure.
3. Utilization of Biomass
The primary energy source that humans have used as food and fuel is biomass. It means humans depend on low-entropy resources that plants make from solar energy. Here I am using the concept of biomass in a broad sense so that it implies both living and dead biological material. Here, most of the fossil fuels (coal, petroleum, and natural gas) are biomass.
The energy we consume in our bodies derives from biomass. Some of our food derives from plants and other from animals, but since the resource value of the latter derives from the former, we can say we depend on plants for food.
We have also depended on plant-derived biomass for fuel. The primary fuel has changed from wood to coal, from coal to petroleum, from petroleum to natural gas. Most of the resource value of these fuels comes from plants. We have kept the low-entropy structure of our body systems and our economic systems with biomass as a high-temperature source and water as a low-temperature source.
Of course, human civilization has not depended only on the photosynthesis of plants. Humans have used waterpower or wind power. Even before the Industrial Revolution, we used them through watermills and windmills, but these could not be the major energy source except in Holland.
Today various technologies to use renewable energy such as geothermal power, solar power, tidal power, wave power, wind power, and so on, are under development, but these will not be the main source of our energy, because they generate power regardless of human demand. So, the biomass power generators must fill the gap between demand and supply.
People rarely regard fossil fuels as renewable energy. This sounds strange. Coal, petroleum, natural gas—all these are now being produced newly and naturally. We regard them as exhaustible because we consume them a hundred times faster than nature produces. The same thing applies to living biomass. If we do not decrease the amount of consumption and consume living biomass instead of dead biomass, living biomass will soon run out as well.
People often say, “Biomass energy is carbon neutral, but fossil fuel energy is not.” This is not true. Living biomass energy is not necessarily carbon neutral and fossil fuel energy is not necessarily carbon positive. Consumption of living biomass is carbon neutral only so far as emitted carbon and sunk carbon keep the balance. If combustion of biomass, whether it is living or dead, exceeds carbon sink, it will increase carbon dioxide concentration.
There is some reason for the belief that biomass energy is carbon neutral, but fossil fuel energy is not or that biomass energy is renewable, but fossil fuel is not. Only a small fraction of living biomass becomes fossil fuel. The rest breaks up and releases carbon dioxide. Using living biomass as fuel emits less carbon dioxide than using fossil fuel and it is far easier to renew living biomass than fossil fuel.
Anyway, if we intend to continue sustainable and carbon-neutral consumption of biomass, we must reduce the amount of biomass energy consumption to the amount of biomass energy plants can produce. The amount of renewable energy is limited. That is why I emphasized the necessity of reducing the world population in the first chapter.
Maybe many people do not agree to such an austere proposal. Some will say, “It is primitive to rely on the natural energy source. We should hurry the development of nuclear fusion energy so that we can get an inexhaustible energy source soon…” Even if nuclear fusion energy comes to practical use and solves the energy problems, the increasing world population will cause a food crisis, because nuclear fusion energy cannot supply energy consumed in our bodies. Even if agricultural technologies keep advancing, global desertification will make the food crisis inevitable.
Here we must reflect on what on earth our progress is. Human progress consists in qualitative improvement of information systems in science, technology, and culture, not in quantitative enlargement of material systems. Of course, the more babies we bear, the more likely to appear the excellent human resources are. But the increase in education investment per capita will also keep producing them without making a big impact on the environment. Thus we can reduce our material civilization to the capacity of the plants.
Now, how should we use biomass in the future? The traditional method, namely direct burning, is not desirable, because it emits various pollutants such as nitrogen oxide, sulfur oxide and so on that pollutes the air. It will be the least harmful to gasify or ferment biomass, collect fuel gasses such as hydrogen and methane to generate electricity through fuel cells.
Some believe naively fuel cells are clean generators that do not emit carbon dioxide. Certainly fuel cells themselves do not emit carbon dioxide, but the production of hydrogen from biomass emits carbon dioxide. To reduce the emission of carbon dioxide, some try to capture carbon dioxide from power plants and subsequently store it in underground geological formations or deep oceans.
It is doubtful whether this carbon sequestration results in the restoration of fossil fuels. We should use more natural and reliable ways to restore biomass energy. Two primary sources of anthropogenic CO2 emission are the combustion of biomass and the production of cement. So, storing carbon in living biomass and limestone (calcium carbonate) is preferable.
As for artificial storage of carbon in living biomass, Osaka Gas Co. Ltd. and Tsukuba city developed a “tri-generation system” that applies waste heat and carbon dioxide as the by-product of power generation to growing plants in greenhouses.High CO2 concentration enhances the carbon fertilization of plants with sink organs, such as melon. The agricultural industry in Holland has already put this sort of tri-generation to practical use.
As for artificial storage of carbon in limestone, it can serve as recycling cement. Used cement is fragile and has quality problems. Jun Iizuka proposes a method of supplying high-pressure CO2 to waste cement powder, abstracting calcium from it by carbonic acid, and producing pure calcium carbonate.
Another way to prolong carbon sequestration is to encourage the construction of wooden houses. It not only stores carbon for a long time, but it also reduces the usage of cement, thus reducing the emission of carbon dioxide. When we pull down wooden houses, the waste wood becomes biomass fuel and reduces the consumption of fossil fuel.
Now that I presented my proposal for sustainability, Let me sum up the proposal.
- To make human civilization sustainable, we must first reduce population. The coming knowledge-intensive economy makes simple labor unnecessary. We should reduce childbirth on one hand and increase educational investment per capita on the other.
- To stop desertification, we should substitute organic agriculture for modern agriculture, eating the marine animal for eating the terrestrial animal, and reduce human excrement to the ground as manure, thus forming a sustainable circulation of nutrients.
- If we succeed in reducing the world population and greening the desert, we can use biomass as fuel. If the production of biomass by plants and its consumption by animals keep the balance, our economy becomes sustainable and carbon neutral.
If human civilization remains thousands of years hence, the terraforming of another planet and the permanent self-sufficient human habitation of locations outside Earth will be possible. Before having such a dream, we should first solve the imminent problems of the resources and the environment to avoid the extinction of the human species.
- Lester C. Thurow. Fortune Favors the Bold: What We Must Do to Build a New and Lasting Global Prosperity. HarperCollins e-books (2009/10/13).
- Joseph Jenkins. The Humanure Handbook: A Guide to Composting Human Manure. Joseph Jenkins Inc. (2016/12/26).
- Miriam Otoo et al. Resource Recovery from Waste: Business Models for Energy, Nutrient and Water Reuse in Low- and Middle-income Countries. Routledge (2018/3/20).
- Prabir Basu. Biomass Gasification, Pyrolysis and Torrefaction: Practical Design and Theory. Academic Press (2018/6/29).
- United Nations General Assembly. “Report of the World Commission on Environment and Development: Our Common Future“. Chapter 2: Towards Sustainable Development; Paragraph 1. Transmitted to the General Assembly as an Annex to document A/42/427 – Development and International Co-operation: Environment; United Nations General Assembly (March 20, 1987).
- Max Roser. “The size of the world population over the last 12.000 years.” Licensed under CC-BY-SA. Based on estimates by the History Database of the Global Environment (HYDE) and the United Nations.
- Max Roser. “Annual world population growth rate (1950-2100).” Licensed under CC-BY-SA. Data sources: Observations: US Census Bureau & Projections: United Nations Population Division (Medium Variant 2015 revision).
- Top 20 countries with the lowest total fertility rate are Hong Kong, Macau, Singapore, Taiwan, Lithuania, Northern Mariana Islands, Czech Republic, Belarus, Japan, Bosnia and Herzegovina, Ukraine, Moldova, Slovenia, Poland, Latvia, South Korea, Spain, Italy, Andorra, Slovakia; while top 20 countries with highest total fertility rate are Mali, Niger, Uganda, Somalia, Afghanistan, Yemen, Burundi, Burkina Faso, Congo, Angola, Sierra Leone, Congo, Liberia, Mauritania, Guinea, Malawi, Oman, Mayotte, Gaza Strip, Chad in this order. Data from CIA (2007) Rank order of total fertility rate, The World Factbook 2007.
- How does education affect fertility rates in different places?" Population Module. Lesson 3. Center for Global Geography Education.
- Halpern, Carolyn Tucker, Kara Joyner, J. Richard Udry, and Chirayath Suchindran. “Smart Teens Don’t Have Sex (or Kiss Much Either).” Journal of Adolescent Health 26, no. 3 (March 2000): 213–25.
- Lester C. Thurow (2003) Fortune Favors the Bold: What We Must Do to Build a New and Lasting Global Prosperity. p.170.
- Source of 1620, 1850, and 1920 maps: William B. Greeley, The Relation of Geography to Timber Supply, Economic Geography, 1925, vol. 1, p. 1-11. Source of TODAY map: compiled by George Draffan from roadless area map in The Big Outside: A Descriptive Inventory of the Big Wilderness Areas of the United States, by Dave Foreman and Howie Wolke (Harmony Books, 1992).
- United States Department of Agriculture. “Glossary of Biotechnology Terms“. Last Updated: 03/18/2009.
- New Farm Field Trials (2003) Organic farming sequesters atmospheric carbon and nutrients in soils – White paper, organic farming sequesters atmospheric carbon.
- Joseph Jenkins (2005) The Humanure Handbook – A Guide to Composting Human Manure, 3rd edition.
- Seiwa Denko (2007) Bio-Lux.
- Osaka Gas (2004) Contributing to Environmental Conservation Locally, Nationally and Overseas. p.4.
- Jun Iizuka (2002) 廃セメントを用いた二酸化炭素排出量削減プロセス. Tokyo University, Department of Environment systems.