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Identifying the limiting factors

One limiting factor is traditional basic cultivation patterns and mind sets. In different social and ecological conditions very different cultivation methods and philosophies have evolved. The most marked difference is that between intensive gardening-like agriculture in densely populated areas of Asia and "industrial" agriculture in those areas of the world that were brought under cultivation by European emigrants or colonizers within the past 500 years.

In the old cultures, land was scarce and population was dense. Thus, a high yield per surface unit was the overriding need. In the Americas, on the other hand, land was abundant, the population was low, and labour was in short supply. Thus mechanization and large scale agriculture were appropriate and successful. At present the latter model dominates world agriculture. Its domination is fortified by mainstream economic theory and international trade interests and rules, as well as by cheap transport and telecommunications. But will it be the proper long-term strategy for feeding the dramatically growing world population in a sustainable way? Would not the "outdated" agricultural models from China, (peasant) Europe, India, and Japan be a more appropriate starting point? Could these older models be modernized and adapted to the needs of the future?

Another limiting factor is underestimation of the real importance of agriculture in the industrialized economies.8 Owing to its minor contribution to the GNP of industrialized economies (typically 2-5 per cent), agriculture is largely neglected in mainstream economic analysis. But agriculture plays a key role in every scenario as the essential life-support system.9 This is due to five major features:

1. Because agriculture is the industry nearest to nature, ecological deficits become apparent much earlier here than in any other branch of the economy.

2. Agriculture satisfies the most basic needs of humankind: it feeds us.

3. The consequences of disregarding sustainable patterns have been more serious in agriculture than in any other sector of the economy; '`modern" industrialized agriculture has turned out to be unsustainable within two generations.

4. The long-term prospects for the world food situation are so critical that, if civilized humankind is to survive, corrective action is urgent.

5. Agriculture is the indispensable source of organic material streams in a sustainable future world economy.

A further limiting factor is that modern economics and management theory have encouraged a short-term and reductionist view of agriculture. Successful industrial strategies, characterized by "lean production," rapidly changing technologies, short depreciation periods, and minimization of external influences in process design, are now being transferred to agriculture.10 The evaluation of agricultural production strategies (systems) by impersonal "market forces" leads to a short-term calculus. But the physical and biological nature of the system itself implies that the appropriate time-frame for measuring sustainable and economically viable agricultural supply systems is much longer: at least 20 years (for example, to observe three periods of a seven-fold crop rotation requires 21 years) and perhaps as much as 100 years (Harrington 1992). Agriculture is an inherently interacting system that should make use of all natural synergism's.

To evaluate agricultural strategy on a short-term basis is to create inappropriate expectations. Thus agriculture is globally being driven towards the industrial model. But this systems coercion is in blunt contradiction to eco-system needs, which require biodiversity (CE 1995), site orientation, and a massive reduction of material flows.

There is a high degree of consensus that sustainable land use in developing countries should rely on small-scale mixed agriculture in order to husband environments with a low ecological buffering capacity as well as to feed and employ the population. But the opposite is demanded for industrialized countries (Schmidheiny 1992). The negative reaction of leaders in developing countries is not surprising. They consider this advice to be self-interested and neo-colonialist; they regard it as an attempt to preserve the oligarchic economic structure of the world economy. Hence they unwisely imitate the inappropriate patterns of the industrial world, even when they are not directly imposed by "Western-style" agro-business.

A logical consequence is that soil erosion and the leaching of agrochemical into groundwater are out of control in non-OECD countries. In fact, more than three-quarters of world soil destruction takes place in the third world. The massive problem of soil erosion demands a drastic change in production systems towards more stewardship and husbandry of soils and landscapes. The present pattern of production is leading to a decrease in the productive agricultural area by up to 16 million ha per year (ISOE 1995). Therefore, without change, a higher production volume for an increasing population would (will) have to be achieved on a decreasing area.

Another limiting factor is water. The exploitation of water resources, which brought nearly a 2 per cent increase in productivity in the first three post World War II decades, cannot be augmented, at least not without major investments and dislocations (as in the Three Gorges project in China). Pollution of water resources by wasteful agricultural practices (especially excessive use of synthetic nitrogen fertilizers and pesticides) will have to be reduced in many cases in order to save drinking water reserves. Inputs of agrochemical must also to be limited in order to guarantee the integrity of food chains.

To compound the difficulties, most mainstream cultivation systems have been brought to a rather high level of productivity. This means that the law of diminishing returns has to be taken into account in planning the future. In the context of the standard model, this implies that higher industrial inputs will be necessary to increase productivity further, thus shortening the time-horizon within which non-renewable external resources (oil, natural gas, phosphates, potash) will still be available. These are the major raw materials for agrochemical (fertilizers, pesticides, and herbicides). These fossil resources are finite and will last at most for some 100 years, if consumption is not slowed down. But the opposite (i.e. acceleration) is the probable outcome of present policies.11

Yet another limiting factor is that the food potential of the oceans (and aquaculture) will not be a sufficient alternative at least as far as fish is concerned. There is strong evidence that the world's traditional fishery resources are also already overexploited (see, for example, Weber 1995).

Is a collapse of the agricultural system inevitable? The logic of the curve of population growth suggests that either humans are already overtaxing the carrying capacity of the environment, or they soon will. This implies a real danger that we will eventually consume our own "seed corn," i.e. our life-support system. Without a basic change in population growth rates, consumption patterns ("lifestyle"), and supply technology, present developments resemble a forest fire in a strong wind. The system's breakdown can be expected.

As far as agriculture is concerned, the limiting factors enumerated above can be summarized in a nutshell: intensified conventional mainstream high-in-put/high-output agriculture is not sustainable in the long run. This is because short-term advantages are offset by long-term disadvantages in the form of increasing destruction and loss of soil and water resources. In addition, the pattern of ever increasing inputs of fossil energy and raw materials cannot continue indefinitely, for reasons of eventual scarcity as well as environmental reasons.

The food needs of an exponentially increasing world population could not be met, in the long run, even if we assume the most optimistic possible increases in area productivity. Besides slowing down population growth, increasing the efficiency of nutrition will be an indispensable supplementary measure (especially the reduction in luxury meat consumption).12

If the present trends of soil degradation and population growth are projected without change,13 there would be very few regions in the world in 2025 able to satisfy the nutritional needs of their own population, even relying on a diet of grain, tubers, and legumes (i.e. cutting meat consumption to a minimum) (ISOE 1995). Therefore the often-heard argument that there is only one way to avoid serious social upheavals in the future, namely to feed the growing world population by employing intensified industrial patterns of production, cannot be a realistic solution.

This judgement is supported by the annual "State of the World Reports" by the Worldwatch Institute, which point to an approaching crisis. In recent times several events and studies have underlined the view that agriculture will be the crucial sector in world economic development. In 1991 the Conference on Agriculture and the Environment, organized by the Food and Agriculture Organization of the United Nations (FAO) and the Government of the Netherlands, analysed the world situation and worked out an Agenda for Action to meet food needs without mining the natural resource base and thus consuming the life-support systems of future generations and probably even of our own. The loss of 5-7 million hectares 14 of arable land per year through soil degradation was reported, with an annual global loss of topsoil running at 24 billion tons. (For an even bigger estimate, see Editor's Note above.) There was a general consensus that the situation demands urgent action. It was generally agreed that it is not only the symptoms of unsustainability in agriculture (land degradation, desertification and deforestation, water pollution, loss of soil productivity and natural processes, diminishing wildlife habitats and genetic diversity, air and climate effects, etc.) that have to be changed. The change must extend to the underlying dynamics of our societies.

Some other studies support this position (Hohmeyer and Gärtner 1992; FAO 1993; Pimentel et al. 1994; ISOE 1995). The reduction in vital agricultural reserve capacity implied by "business-as-usual" scenarios is likely to lead to increased starvation in developing countries and to mass migration. It may also to social, economic, political, and - last but not least - military conflicts. In worst-case scenarios, such catastrophes could destroy the social achievements that most countries value so highly and assume to be guaranteed.

Some economists dismiss these warning studies with epithets such as "neo-Malthusian," the implication being that Malthus was long ago disproved or discredited. There are even strategic papers, such as the "Study on the perspectives for the rural areas in the European Community" of the Netherlands Scientific Council for Government Policy (1992), that see such large long-term surpluses of agricultural goods that only about 50 per cent of the productive land of the European Union will be needed in the future.

Those who attack Malthusianism per se can be met by pointing out that there is a decisive difference between the present situation and that in the eighteenth and the nineteenth centuries. Even in the nineteenth century there were still large new areas available for colonization and cultivation, especially in the Americas. Moreover, older cultivated areas and species had not reached ecological limitations associated with mono-culture, chemical use, and toxification of soil and groundwater.

As to the food surplus scenarios, it has to be pointed out that all these scenarios are based on the assumption that industrialized countries will continue to run their economies unsustainably. Societies that cover basic demands for organic raw materials and energy by plundering non-renewable fossil resources within a few generations have no need to reserve land for an enduring harvest of solar energy. By limiting agricultural production to the food sector and by boosting food production via cheap fossil-based inputs (chemicals and energy), they can and do produce artificial, but temporary, surpluses. These are not sustainable, however.

Because the introduction of general conditions of sustainability cannot be circumvented in the long run, agricultural politics is confronted with a (politically) painful dilemma. The choice is between short-term maximization even to the point of generating unwanted surpluses - and long-term sufficiency. This dilemma cannot be resolved by relying on market forces alone, because the latter are unavoidably short term and private in nature and do not reflect the larger public interest.

Anticipatory strategies leading the market to a long-term optimum are therefore necessary. The reasons are evident: population growth cannot be stopped quickly; water resources have already become scarce, especially in developing countries (FAO 1993); the use of chemical fertilizers and pesticides in agriculture has to be controlled and curtailed in order to protect the groundwater, especially in developed countries (OECD 1993). The accepted principles of precaution and plausibility in risk management underline this position.

In this context a few remarks on international trade policy as it concerns agriculture are appropriate. The results of the Uruguay Round of the General Agreement in Tariffs and Trade (GATT) reflect the short-term market calculus (GATT 1994). Calls by environmentalists for measures allowing protection of future-oriented long-term sustainable agricultural systems within a system of fair trade are denounced by trade negotiators as "green protectionism." Trade negotiators argue that agriculture must accept the same rules as the industrial sector. Yet industrial undertakings normally do not need a site-oriented design. Their adaptation time to changing circumstances is shorter, and the same holds for the depreciation period. Further, the co-production of public goods (such as harmonious landscapes, biodiversity, and potable water) is, for practical purposes, non-existent in industry. The timeframe of the trade calculus is even shorter than the industrial one.

In addition, long-term food security concerns seem inconsistent with providing favourable trade treatment to regions that gain a short-term comparative advantage by operating unsubstainably. Examples include risking soil erosion through irrigation with "fossil" groundwater and clearing rain forests and steep hillsides to provide cattle pasture for less than a decade before the thin layer of topsoil is lost. Myopic decisions in international economic development planning are the rule, rather than the exception. Proven and sustainable cultivation systems are routinely sacrificed for unsustainable short term advantages, not only in the Amazon or Central America and in disadvantaged areas such as the European Alpes-Maritimes and Ligurian Alps, terrace agriculture in Yemen, or mountain agriculture in India and Pakistan, but also in the advantaged areas of the northern hemisphere.15

The so-called "green box" measures (the "Blair House Agreement" of 1992) are an attempt to mitigate some symptoms.16 This has broadly the character of a "social end-of-the-pipe treatment strategy," because the listed measures are strictly palliative. They leave the underlying dynamics unchanged. Therefore the environmental impacts of agriculture are not changed at the roots. (For more details see Editor's Note above.)

Does this mean that agriculturalists, as a minority that cannot significantly influence the economic mainstream, must be advocates of intensification of the presently dominating patterns of agricultural production in order to keep humanity alive and fed in the short run, in spite of the warnings of ecologists, environmentalists, and rural developers? The key to a strategy of hope is the answer to the following crucial question: Are there other systems of sustainable agriculture at our disposal that can achieve the high area productivity of mainstream (high-input/high-output) agriculture but that have the potential to feed the growing mega-cities of the future?

The technological feasibility of sustainable agriculture

It should not be necessary to emphasize yet again to the readers of this book that an essential characteristic of sustainable future economic systems must be to minimize the energy and material inputs per service (production) unit, in all sectors. In the realm of food production, organic agriculture is the most appropriate concept. By careful husbanding of soils and landscapes, by relying on site-oriented biodiversity in order to be able to use a maximum of natural synergisms, and by intensive nutrient recycling it minimizes external inputs. Thus, it achieves a maximum net harvest of solar energy in forms usable to humans. In this way it preserves and even improves the soil and achieves the highest possible yields in a way that can be practiced for a virtually unlimited time-horizon. In the remainder of this paper, small-scale mixed agriculture in developing countries will not be addressed specifically. Its merits are widely accepted and documented (e.g. Hiemstra et al. 1992; Radtke 1995). I refer to the experience of institutions such as the Bakara Agricultural College in Molo, Kenya. This started as a conventional training school, but it has evolved into an exemplar of site-oriented small-scale mixed agriculture including agroforestry in order to achieve a maximum of sustainable yield and a diverse diet, unburdened by the residues of agro-chemicals detrimental to human health.

The emphasis hereafter is on the potential of organic agriculture in the present bread-basket countries of the North (i.e. in the industrialized countries). In the following paragraphs, the principal concepts, historical examples, and actual comparisons are presented as evidence that there is a realistic and socially beneficial way out of the "Malthusian food trap" if we are prepared to surmount and challenge the rules of the present game.

The gardening concept

There is evidence that a gardening-like cultivation system with a high input of labour (~0.3 persons per ha), a high turnover of nutrients, and a balanced pattern of mixed cropping is capable of out producing low-labour (mechanized) agricultural production systems by at least three-fold. In times of worldwide structural unemployment it would be a wise strategy to rely on this concept in order to meet future food shortages. But the intelligent intermediate step would be to preserve the skills needed to manage highly productive mixed agricultural systems that later can be more easily intensified towards a gardening like pattern of cultivation. In this light, small-scale mixed agriculture can be seen as the starting block for stepping up agricultural productivity in the future in a sustainable way.

Germany in World War II

I observed an example of (enforced) low-input/maximum-output agriculture in my youth. I was adopted by a farmer family after my father was killed by the Nazis. According to all traditional expectations, Germany - being cut off from all external supplies of food, fertilizers, and agro-chemicals - should have come to starvation point within at least one or two years. But, in spite of massive military destruction, organic agriculture guaranteed the necessary minimum supplies until the end of the war. In fact, invading Allied forces found and captured strategic food reserves in storehouses. Over and above its own population, the German agricultural system had to feed an additional customer in the east because the Red Army could not rely on its own supplies. The dramatic (but temporary) food shortage of 1945 occurred because spring planting was impeded by warfare and seeds were destroyed or consumed for food throughout much of the countryside.

The example of German war agriculture also answers one standard argument against small-scale mixed agriculture, the argument that long-distance supply to towns and cities is not manageable. Even with primitive means (such as horse-drawn wagons and trucks powered by gas from wood pyrolysis), with processing and packaging mainly in small units by hand, an efficient system of collection, storage, and distribution was organized. This task would surely be achieved much more easily by employing advanced technology (microelectronics, informatics, and telecommunications) for networking and designing satisfactory supply systems. Crisis scenarios that were simulated in the 1980s for the Netherlands, Germany, and Finland confirm this past experience (Bakker 1985; Henze 1980; Kettunen 1986).

The potential of organic agriculture in temperate climates

Some preliminary remarks have to be made with respect to the validity of existing comparisons between conventional and organic agriculture.17 First there is a general tendency to underestimate the productivity of organic agriculture for four reasons:

1. Organic agriculture stems from a revolutionary `'bottom-up" movement. It still has relatively little scientific support, because R&D funding by government and industry is directed to support mainstream activities.

2. In order to achieve full productivity by building up the humus content of soils and optimizing the farmer's skills (including the choice of appropriate crop rotations and intermediate crops), a "learning" period of about 10 years is typically necessary.

3. Organic farmers have always asked for support because of the initial yield-lag during the transformation phase.

4. In many cases shortage of affordable labour is a limiting factor, because the question of labour intensity cannot be addressed within the present system of agricultural support and mainstream economic philosophy. This bottleneck could be overcome by a future ecological tax reform that taxed the consumption of nonrenewable materials and primary energy carriers on the one side and reduced the direct and indirect taxation of labour on the other.

Thus assessment of the productivity potential of organic agriculture has also to take into account these short-term temporary disadvantages. Comparisons between conventional and organic agriculture, assuming similar endowments of labour and machinery, suggest a much higher energy efficiency for organic agriculture. The improvement ranges from 48 per cent to 64 per cent. But there is a corresponding short-term drop in yield of up to 30 per cent (Haas and Köpke 1994; Berardi 1977). One study observed a 10 per cent reduction in natural produce yields when comparing 14 pairs of conventional and organic farms in the eastern central states of the United States (Lockeretz et al. 1976). A 1980 study by the US Department of Agriculture (USDA 1980) in the US Midwest found not only a much higher energy efficiency for organic agriculture but also similar or better average yields per surface area unit. In the case of wheat there was no significant difference between the two. In the case of soybeans, organic methods produced 14 per cent higher average yields.

In Europe a number of similar studies have been made (Granstedt 1990; Rist et al. 1989). They have estimated a 20-30 per cent reduction in yields, based on the average performance of organic farms. Bechmann et al. (1992) propose compensating for the yield reduction by changing the European diet (reducing the present physiologically detrimental over consumption of meat). Meyer (1989), building on a study by Rist, has calculated for the Canton of Zug (in Switzerland) that only 1,430-1,600 m2 (0.14-0.16 ha) of organically farmed land would suffice to feed one adult person. This differs favourably from the 0.5 ha demanded by Pimentel et al. (1994) in order to provide a diverse nutritious diet of plant and animal products. To take an extreme case, a diet based largely on potatoes could feed an adult person from only 110 m2 assuming maximum productivity and from 300-400 m2 assuming average productivity (Walker 1979).

Based on these facts it is possible to make the following rough judgements. The earth is now providing about 4.6 billion ha of land usable for agricultural purposes. About one-third is arable land and two-thirds permanent grassland (ISOE 1995). Divided by a world population of 5.77 billion in 1996, the current world per capita endowment amounts to 0.25 ha of arable land and 0.50 ha of grassland. Thus there is still sufficient (but not ample) room for adjustment towards a global eco-restructuring of the agricultural supply systems without the threat of increased starvation. On the contrary, given appropriate incentives, humanity could save its resource base for future generations and still achieve food security.

In assessing future potentials, the performance of the best farmers should serve as a measuring rod, because they are the spearhead of future development. Personal observation of Austrian organic farms, especially the well-documented model farm of Hermann Pennwieser, shows that within a period of 10 years the humus content of soils increased by one-third (1.5-2 per cent per annum), and that soil life, soil structure, and water storage capacity also increased significantly (Sinabel 1991). One surprising effect is also that the incidence of plant diseases actually decreased, which indicates a strengthening of the plant's immune systems. The average yields of these organic farms are at the same high level as in comparable Austrian conventional farms.

Besides estimating the potential of sustainable organic agriculture, it is also important to assess the resource conservation potential of organic agriculture if it were adopted globally. The energy efficiency of organic agriculture has already been noted. In addition to the examples cited above, a US study by Lampkin (1990) concluded that conventional high-input/high-output agriculture consumes 2.3 times more energy compared with organic farms.

The contribution of organic farming vis-ā-vis soil erosion is vitally important. There is clear evidence that soil erosion can be drastically reduced. Reganold et al. (1987) observed a yearly erosion of 8.3 t/ha on organic fields and 32.4 t/ha on conventional ones. Erosion is reduced by three major characteristics of organic agriculture:

- crop rotation, the concept of evergreen agriculture (continuous coverage of the soil by plants), mixed cropping, and underseeding reduce the susceptibility of soil to erosion (Lindenthal et al. 1996);

- augmentation of the humus results in a better soil structure, a higher stability of aggregates, greater penetration by roots, and better water storage capacity (Gehlen 1987; Reganold et al. 1987; Maidl et al. 1988; Beyer et al. 1989; Unger 1989; Diez 1991; Mäder 1993);

- careful (soft) soil cultivation also cuts the risk of erosion.

Higher plant nutrient efficiency

It is usually argued that there are no alternatives to the present high inputs of nitrogen, phosphorus, and potassium (NPK). If all farmers of the world were to follow the high-input model, the minable deposits of phosphorus would be exhausted in about 80 years (Scheller 1991, 1993). The same holds for potassium and for fossil organic resources, which are the base of nitrogen fertilizers (Barney 1980). In addition, the high energy input for the supply of mineral fertilizers has to be taken into account. Nutrient-efficient cultivation techniques are, therefore, a conditio sine qua non for long-term sustainable food supply

Organic agriculture tries to achieve maximum nutrient recycling by integrating plant and animal production and by using all by-products and wastes. Following this concept, nearly balanced nutrient cycles can be achieved (FAT 1994). As far as phosphorus and potassium are concerned, use of the nutrient reserves in the soils and of their geo genous potential, combined with the recycling of organic residuals, can be considered to be a proper intermediate strategy. In the very long term, agriculture must achieve a near closure of nutrient material cycles.

Nitrogen efficiency deserves a separate comment. Conventional agriculture now imports nutrients in nearly unlimited quantities, which have resulted in a nitrogen surplus (N-surplus) in areas where this has been going on for many years. In contrast, organic agriculture limits itself to nutrient recycling and to legumes as sources of nitrogen. In addition, organic farms normally observe the restriction of not more than two large animal units per hectare. Because organic farms are forced to economize on nitrogen inputs, the N-surplus on organic farms is much lower. For the agricultural areas of Germany, for the years 1991 and 1992, Isermann et al. (1994) have calculated a surplus of 145 kg N/ha. In contrast, organic agriculture caused smaller N surpluses of 37-76 kg/ha (Haas and Köpke 1994). This is clearly reflected in the nitrate content of groundwater. Research in Bavaria found that on average the nitrate content was 79 ppm/litre under areas of conventional agriculture with livestock raising and 42 ppm/ litre without livestock (Brandhuber and Hege 1992). Under organically farmed areas the nitrate content of groundwater was, on average, 27 ppm/litre, thus being within safe limits.

Agriculture has always tried to optimize the living conditions of plants and animals and to protect them. Organic agriculture has the same aim. Enlightened organic agriculture therefore does not refuse external aids completely (as some fundamentalists do), but it cuts them to a minimum and tries to rely mainly on the employment of natural synergisms and intensive care. Under these auspices, further increases in the effectiveness and productivity of organic agriculture can be expected. This judgement is underpinned by the fact that political support and public funding of research work in this field are also increasing (USNRC 1989; Lindenthal et al. 1996).

Based on the above evidence, it can be said that pragmatic organic agriculture is a realistic pathway to feed the growing world population and to secure the natural resource base needed for a long term sustainable future. But it has to be complemented by other measures, especially efficiency of food distribution. Most important of all, there must be effective measures to stabilize world population in order to secure a high quality of life for all citizens of the globe in the long term.

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