Low Input Farming: Merits and Limits

Extracts from Ceres No. 144 (Vol. 25, No. 6)
November-December 1993

Conversation with the counter-revolutionaries

Inspecting the toolbox

Strength through flexibility

Conversation with the counter-revolutionaries

Just how organic is the low-external-input movement?

When is less really more, and new actually old? The catchwords and tenets of the post-Second World War Green Revolution in farming are fast being replaced in the public mind by those of a counter-revolution, as yet unnamed, whose own vocabulary sounds properly technocratic, but which in fact harks back to traditions that may be hundreds of years old: words like "sustainability," "biodiversity," "integrated systems" and "low-input" now buttress the more familiar "organic farming." But what is everyone talking about, and just how organic is the "low-input" movement? Bradley Busetto asked the International Federation of Organic Agriculture Movements (IFOAM) for its view. IFOAM members Susan Milner, Coen van Bueningen and Boudewijn van Elzakker responded.

Susan Milner and Coen van Bueningen

BB: What are the objectives of IFOAM?

CVB: The objective is to further organic production, plain and simple, and thus represent every link in the production chain. This includes the agricultural worker (through farmers' groups), trade groups, processing groups, and standards and certification boards. It's an attempt to provide unity to the growing organic movement. Over 600 groups at all levels in more than 80 countries are represented, with many thousands of individual farmers involved.

SM: We're not interested just in the organic product, but in the entire process of organic production. Looking beyond the technical level, we're trying to grasp social aspects - like fair trade - and look at them from the point of view of groups in the South who see agriculture as not just a technical solution but part of a social/economic dynamic as well.

BB: What are the advantages of turning to organic agriculture?

BVE: It's difficult to generalize, because examples of successful organic farming systems can be found in many different conditions. A major advantage of course is that it stops environmental degradation. Organic techniques are used to regenerate degraded areas. A second advantage is that, because of diversification, it offers farmers a much more secure income than when they rely on only one or two outputs. The consumption of byproducts improves the health of the farm family.

Thirdly, farmers maintain nutrient balances in the soil through locally available organic materials or recycled farm wastes. Soil nutritional status is thus better maintained in areas where access to synthetic inputs is limited or where they are too expensive.

Finally, health hazards posed by pesticides and herbicides fall by the wayside.

BB: Exactly what is low-external-input agriculture; what are its principles?

BE: Low-external-input farming reduces as much as possible the use of external inputs like pesticides, herbicides and synthetic fertilizers and replaces them with internal inputs. The basic principle is that farming is seen as both agro- and ecosystem management. The farmer is managing a farm with coherent diversity. The important concepts are diversification of both crops and animals, crop rotation, and organic matter cycles. Low-external-input agriculture does not prohibit synthetic inputs. It's just that when the principles are applied, the need for synthetics disappears. Techniques vary from the use of traditional knowledge to use of modem bacterial herbicides and insecticides which replace their synthetic equivalents. Mixed cropping, green manuring, composting, use of local organic materials, reduced tillage and biodynamic preparations are also included. These things are little more than common sense. Developing these skills with the farmer is the biggest problem.

Low-external-input agriculture does not prohibit synthetic inputs

BB: What does the au courant word of the day, "biodiversity," imply?

BE: Simply that biodiversity sustains the genetic resource base of both crops and animals, while improving the chances for natural control of pests and diseases. Also, it improves the system's productivity and the agrosystem's sustainability.

BB: How accepted is organic agriculture today?

CB: Organic farming isn't exactly new. Many so-called traditional systems have worked for a long* time without external inputs and chemicals - and are still working. The best proof that organic farming can work is that it has worked for a long time. This doesn't mean it can't be improved. It certainly has to be. But to improve it, it's not necessary to use external inputs. There are other ways. Here I feel FAO is weak. The Organization feels that agricultural improvement means putting in chemicals. That's a one-sided view. In some cases, that approach is viable, but in others it's not. And I feel we have a role to play in developing traditional systems that are still low-external-input without chemicals. The means to do this involves the concept of nutrient balances including organic matter. Science today has a lot more information about what is happening with soil resources, and with these data many traditional systems can be improved without chemicals. There are other ways.

BB: What about regions, like parts of Asia, with high population densities and ever more degraded soil conditions, that have to keep pumping in more nitrogen to keep up their rice production? How can low-external-input agriculture work in places like these?

BE: The fact is that very often systems are being degraded because the external inputs are not properly used. The Green Revolution technology is only accepted marginally. It's amazing that in the Philippines rice is fertilized with urea only. Does the crop not extract other nutrients? The right use of external inputs is a matter of education and improving farmer knowledge. In organic farming, the need for external inputs is reduced through nutrient cycling and an input like labor. When other external inputs are necessary, they are organic materials. You can make biologically intensive production systems with above average yields, employing more people, using renewable, organic resources.

SM: Admittedly, you have to balance population pressures to some degree as well. If you have degraded soils, you need to build up soil fertility, and when the fertility is there you have to try to maintain it. The problem at the moment is that people have tried for too long to use the soil as something to extract from, without trying to recycle things back into it.

The intensification of an agricultural system need not mean automatically putting in more chemicals. There are different ways - intercropping, green manuring, recycling of manure, planting things at different times, so as to maximize the potential of a piece of land. You can use cropping systems so that you have a diversity of crop species that complement each other. You can plant crop combinations that are less susceptible to pest attacks, so that you don't have to keep relying on the pesticides used with monocultures. This is a wholistic farming system which is much more complex and thus both knowledge-intensive and management-intensive.

Integrated copping: in Thailand, mixed coffee and upland rice, planted in bench terraces, help to slow once-severe soil erosion

BB: How do low-input systems compare with high-synthetic-input agriculture in terms of yields, especially in the developing countries?

BE: Here's a good example: The International Rice Research Institute (IRRI) in the Philippines is breeding varieties which produce up to eight tons per hectare twice a year, with high technology and high chemical inputs. This is the maximum yield at the moment in high-external-synthetic-input agriculture. However, the average Filipino fermer does not have sufficient access to these inputs, or finds them too expensive, and instead produces 2.5 tons per hectare, twice a year. In China you can still find traditional, intensive organic systems where even human excreta are recycled to the fields; It has been documented by Dr. Li Zhengfang, a Chinese government scientist, that in such intensive systems up to five tons are produced, twice a year. So here you can see the optimum yield with high-external-synthetic inputs, compared to the reality for the average farmer, and somewhere in between that, what is being achieved today with internal organic inputs in China.

BB: Do nutrition problems arise when farmers, especially in the developing world, stick to only one crop in hope of high yields?

BE: Yes. For instance, some Filipino farmers are producing large quantities of rice, and are still malnourished because they cannot purchase other foods. In the past, farmers were not just growing rice, but had more diversified systems. There were, for example, fish, snails and edible frogs in their paddy fields, providing food and manure. The monocropping of today, coupled with increased use of pesticides in the fields, means that no other substantial animal life exists in the paddy fields any more. The farmer has to live completely on his rice, and the sales of his rice, where in the past part of his protein intake was covered from the fish in his paddy field. In low-external-input agriculture we are striving to return to these traditional, diversified farming systems.

BB: Where have you seen successful applications of modern low-input agriculture?

BE: I was recently in the Philippines, as a consultant for UNCTAD - an agency which has gotten the message about organic agriculture - and I saw very successful examples of rice farms which had diversified into vegetables, fruits, fish and some small farm animals. The farmers had a much better income than from rice alone, and the nutritional and health status of their families was much better too. In Nicaragua, we've seen an alley cropping system introduced that was sustainable, increasing crop yields and feeding some animals, so that farmers actually stopped using their former method of shifting cultivation. The only inputs were seeds of leguminous trees and knowledge. Very often training of farmers is the only main input required. Not all of the techniques used are truly "modem," but are very often traditionally based, so that farmers pick up on them easily. The main idea is diversification, meaning both crop diversification and rotation, and a diversity of animals, if possible. The concept of a mixed farm with crops and animals subsisting together is important. Secondly, one must focus on the optimum management of organic matter and nutrient cycles.

BB: How can people in a country with degraded soils and high population growth survive during a conversion to modern low-input systems?

BE: What is important in the conversion period is to introduce strict organic matter management, to improve the organic content of the soil, while at the same time continuing to feed the local population. In lowland rice-growing areas, planting a leguminous crop like lablab beans (Dolichos lablab) restores depleted nitrogen, improves soil structure, provides a fodder for animals and even humans, who can eat the leaves as a vegetable and the beans as a source of protein. This crop can be grown instead of rice, but also in between rice crops, during the conversion period. In upland areas with high population density you often see a distorted kind of shifting cultivation. Here you can introduce an agroforestry system like alley cropping, which stops erosion and is more productive and sustainable. It certainly isn't always true that yields fall when you convert to organic. When you change from rice monocropping to rice/fish, the system'' s productivity (including rice and fish output) is higher. Given proper crop rotation, high population communities should be able to eat during the conversion period.

BB: What about the issue of costs? Isn't low-external-input agriculture quite labor-intensive, and thus costly?

CB: This is an argument that is often used - wrongly. In many places, yes, low-input agriculture is more labor-intensive. But in countries in the developing world, this is not such a problem. Labor there is relatively inexpensive, while chemicals and mechanization are correspondingly expensive. If all of the subsidies are taken off farming with chemicals, the chemicals become yet more expensive. If chemicals aren't used, the savings can outweigh the added cost of extra labor.

SM: The purchasing power of people who buy food is very limited in the developing world. If you apply a high-synthetic-input system which is quite costly in the production stage, you inevitably end up passing this cost on to the consumer. If the agricultural market were consumer-driven, and not distorted by subsidies, perhaps the consumer would not pay the high prices. Therefore the production system would be forced not to be costly, and the farmer would stop using purchased chemicals. I'm told this has actually taken place in certain areas of Nigeria.

A load of manure: farmers in the mountains of Bhutan improve soil condition by transporting animal waste to their hillside fields

BB: Can low-input farming produce higher net incomes for farmers in marginal areas?

BE: Yes, sometimes. In a diversified system there are a lot of by-products, which the farmer might use for his own nutrition or sell on the market. When a farmer has animals for traction, for instance, he grows fodder for his animals, while the animals produce manure, draft power and perhaps also mill. When the farmer feeds waste products to a pig, the pig produces meat or cash, as well as manure which the farmer can use to fertilize his fields. A closed nutrient cycle results, and higher system-wide incomes may result.

BB: So the crucial economic factor isn't just the elimination of expensive chemical inputs, but rather the importance of diversification?

BE: Yes, absolutely. When the farm is diversified, the result is that the farmer needs less chemicals and synthetic fertilizers, and in general has fewer external costs.

BB: Do you think subsidies would be helpful in future wide-scale conversions to organic agriculture in developing countries?

BE: I have my doubts as to whether subsidies on organic products will work well. In all countries - developing and developed - there is a lot of administrative misuse of subsidies. And it also costs governments lots of money (to fund subsidy programs), which is not really attractive, especially in developing countries. It would be more attractive to tax the less environmentally friendly inputs, such as herbicides or fertilizers - call it an ecotax, if you like. This would mean income for the government, and it would also be easier to regulate.

BB: Have you seen any serious change in attitude from traditionally agribusiness- influenced governments toward organic farming?

SM: I think there has been a realization that certainly in Western agriculture the system in place has not achieved its objective.

BB: What was its objective?

SM: In Europe, at least, it was food security. Now there is an overload of food. There is overproduction because the whole market has been distorted by different incentive schemes, to make sure farmers were given a guaranteed price. This has led to more intensification to get higher yields, and that has driven soil degeneration. This intensification has been through increased inputs, increased mechanization, use of high-yield varieties - all the things people associate with the Green Revolution. As a consequence of seeing the need to change policy in order to stop the surplus, and the problems of pollution and soil degradation, there is now an increasing tendency to look at what low-external-input systems have to offer. And, at least from the donor side, people believe now that low-input systems should be developed in the developing countries as well.

BB: Are the attitudes of developing country governments changing?

BE: Unfortunately, they are not changing too quickly. Since the Green Revolution, government policies especially in the developing world have -been centred on high-input agriculture, and there is very little tendency to look for other technologies. In developing countries, organic agriculture is so far entirely the business of NGOs. There is usually a big gap between the ministry of the environment and the ministry of agriculture. Also, development aid and credit programs like the International Monetary Fund (IMF) and the World Bank are still really based on this Green Revolution concept of supplying farmers with inputs and everything will be OK. But this is obviously not the case. A change of mentality is required within the international organizations, especially with the funders, and perhaps then local changes will follow.

BB: What are some of your observations, good or bad, of FAO?

SM: There seems to be a shift toward lower-input agricultural systems, at least at the policy level, which is good. Also, integrated pest management and integrated nutrient systems are currently being talked about at FAO. However, FAO has not provided clear definitions of these new integrated, wholistic concepts.

"Research on organic farming does not reach the users - the farmers"

CB: These integrated, more wholistic pest and nutrient systems suppose a system completely different from FAO's structure, and FAO has still not adapted.

BB: What are the major obstacles preventing the wider dissemination of organic agriculture worldwide?

SM: I think access to information is a major problem. People who want to know about low-input systems - not just stop using fertilizers or chemicals, or whatever, but to actually know how to farm in a sustainable way - don't necessarily have access to the proper information. I think there must be some additional research on this issue. There is a need for training programs which directly instruct farmers, and train extension people in low-input systems, so that a critical mass forms of people involved, and the information can be passed on. At the moment, there isn't the information available, and the extension services are not trained in low-input agriculture.

BB: Are you working on this problem?

SM: A lot of research has been done on organic agriculture, but the information does not reach the users, the farmers. Right now we are creating a useful network of organic agriculture information that can be used particularly in the developing world. A lot of this information is in isolated areas. We should focus on farmer-based research on low-input systems, to get the information available to those who need it, to develop training materials on low-input systems. There is a need to build on what is happening and to communicate between the different actors - research institutes, NGOs and farmers - so that they are all actually reinforcing each other rather than working in isolation. We would hope also to create a mutual forum where the different actors can come together to exchange ideas. What we hope is that there will be a shift from ecological agriculture, low-input agriculture being somewhat marginal to being somewhat mainstream. For this, the people making policy decisions must be aware of the potential.

Inspecting the toolbox

Three alternatives
But is it sustainable?
Example: the virtues of velvet bean
Example: water buffalo health care
Example: crop-livestock-fish farming

A look the means for achieving sustainable agriculture

By Coen Reijntjes, Bertus Haverkort and Ann Waters-Bayer

Thirty years after the launching of the Green Revolution - and despite its outward successes - delegates to the United Nations Conference on Environment and Development (UNCED) were forced to admit that crop yields are stagnating or even declining in many countries, rural poverty is increasing and the natural resource base in far too much of the world is being seriously degraded. Concluded the conference: "Major adjustments are needed in agricultural, environmental and macro-economic policy, at both national and international levels...to create the conditions for sustainable agriculture and rural development."

Before starting to make those adjustments, however, it might be a good idea to look through our technological tool box and see what kind of equipment there is to work with. If we pick the wrong tools, the process of adjustment could be reduced to mere cosmetic tinkering - and the pressure of earth's growing populations and deteriorating environment won't leave time for that.

Three alternatives

Essentially, there are three alternatives available: 1) Integrated Green Revolution Agriculture, 2) Organic Agriculture, and 3) Low-External-Input Agriculture. The differences between the alternatives are not always apparent, and in many cases they overlap. What each can contribute to "feeding the world" depends on specific situations, including the existence of external factors, such as subsidies that make inputs more or less expensive and the capacity of farmers, development workers, researchers and policy-makers to adapt to new conditions.

Integrated Green Revolution Agriculture - Under this alternative, the basic tools of the Green Revolution - intensive use of external inputs (synthetic fertilizers, pesticides, herbicides), increased irrigation, development of high-yielding hybrids and the mechanization of labor - are retained. But much greater efficiency is imposed so as to limit damage to the environment and human health. Some organic techniques are also selected and combined with the high-input techniques to create integrated systems (Integrated Plant Nutrient Supply, Integrated Pest Management) that reduce the need for toxic chemicals. Sophisticated biotechnology is employed to produce higher-yielding or pest-resistant plant varieties.

This option may be a possibility for regions with very favorable production conditions - including good soils and climate, the availability of large amounts of investment capital and the existence of the necessary infrastructure (research facilities, extension networks, road and transport grids, etc.).

Organic Agriculture - This option excludes the use of inorganic chemicals altogether, relying entirely on mechanical and organic/biological techniques to maintain soil fertility and sustain yields. Many of its proponents agree, however, that a transition period is sometimes necessary, in which use of synthetics can be scaled down gradually. Organic farming tends to work best where sufficient organic material is naturally present or where chemical fertilizers are not available.

Low-External-Input Agriculture - An increasing number of farmers, development workers and scientists are coming to the conclusion that capital-intensive Green Revolution techniques are simply not a feasible alternative for the poorest of the 1.4 billion farmers who live in tropical regions with ecologically, geographically and developmentally less favorable production conditions. In these relatively diverse, complex, risk-prone areas, far away from markets, external inputs are either too expensive or simply not available. To optimize productivity, farmers must depend on local resources and ecological processes, recycling and site-specific genetic material. External inputs can't be excluded but should be used strategically so as to complement internal inputs or deal with emergencies, such as unexpected pest attacks. Social factors must also be taken into consideration, using resources such as indigenous knowledge and institutions to foster social cohesion, self-reliance, stronger local economies and human dignity.

These, in fact, are some of the basic ideas behind low-external-input agriculture.

But is it sustainable?

Unfortunately, just like Green Revolution agriculture, low-external-input agriculture is not always sustainable. Farmers are obtaining a significant part of their income from nutrient-mining, and degradation of agricultural land is widespread. Considerable human and financial investment will be needed to regenerate it.

The technology needed to make low-external-input agriculture sustainable can come from various sources: agro-ecological science; empirically developed ecological farming systems (organic farming, permaculture, regenerative agriculture, natural farming, biodynamic farming etc.); traditional and indigenous knowledge, and new directions in conventional agricultural sciences. Frequently, the same techniques can be used both to make low-external-input agriculture more sustainable and to make Green Revolution agriculture less chemical-dependent. Indigenous knowledge, based on farmers' own experiences with their local agro-ecosystems, provides a basis for technology development. Where innovation and experimentation by farmers have been stimulated through participatory technology development, rehabilitation of site-specific systems has succeeded.

Small stock an integral part of most organic systems, providing food, a source of cash income, as well as mature

Scientific understanding of truly sustainable low-external-input agriculture is still in its infancy, but some basic principles have emerged to guide the process of system development:

1) Improve conditions for plant growth by managing organic matter and enhancing soil life. Soil life and soil organic matter play a key role in enhancing soil structure, the availability of nutrients and water, and in preventing nutrient and soil losses in tropical agriculture. But this has been generally acknowledged only recently. A soil cover of dead or living plant biomass provides a favorable microclimate for soil life, protects the soil from erosion by sun, wind and water and adds important nutrient reserves.

2) Make better use of nutrients and balance nutrient flow. Nutrient deficiencies and imbalances are the main constraints to crop production and health. A negative nutrient balance means the natural capital of the farm is being mined, yield and protective plant biomass cover will gradually decrease and the system will degrade. Where sufficient external inputs of organic or chemical fertilizers or purchased fodder or concentrates are not available, other technologies can be used. Prevention of erosion, nutrient harvesting, recycling of organic matter, nutrient pumping by deep-rooting plants, fixing nitrogen and mobilizing phosphates, using animals to collect nutrient and organic matter and careful handling of fertilizers can help to prevent and compensate for losses and exports of nutrients and organic matter. If compensation cannot keep the nutrient flow in balance, integration into a wider market economy should be limited.

Example: the virtues of velvet bean

Farmers in small villages on the northern coast of Honduras are planting velvet bean (Mucuna pruriens) along with maize to obtain high yields, control erosion and lower weeding and land preparation costs.

In this humid tropical region the mean temperature is 28°C, precipitation averages more than 3 000 millimetres a year, and altitudes vary from sea level to high mountains. Cropping seasons are January to June and July to December, but most farmers grow only one maize crop a year during the first season. Farmers using velvet bean for the first time sow it one to two months after sowing maize. When they harvest the maize, they leave the belt-over stalks on the fields. Velvet bean starts covering the stalks and soon takes over the field. By December, large quantities of legume foliage (50 to 70 tons per hectare) begin to dry out and cover the soil with a layer up to 20 centimetres thick. The next maize crop is planted through this layer, which suppresses weeds and allows adequate establishment of the maize. In the second year, velvet bean seeds volunteer from the year before, and the cycle continues with the sowing of new maize. The farmers obtain maize yields of 2 700 to 3 250 kilograms per hectare - more than double the national average - without using chemical fertilizer.

The continuing use of legumes is bringing about changes in the entire farming system. Plowing is being replaced by no-tillage, and migratory farming is slowly disappearing because farmers have found a cheap and simple way to make their land more productive.

Farmers adopted velvet bean without promotion by private or government agencies. Because they are familiar with growing maize, they quickly recognized the benefits of the innovation. Most of their income comes from maize. Low yields mean low income, which was the situation before velvet bean was introduced. Moreover, using velvet bean costs next to nothing - the seed is passed on from farmer to farmer. Because cultivation of velvet bean fits into the normal farming practices for maize, farmers can make more effective use of labor and resources. For more information contact: CIDICCO, Apdo. 278-c, Tegucigalpa DC, Honduras.

3) Manage flows of solar radiation, air and water to improve production and minimize damage. Flows of solar radiation, air and water can be manipulated with plant canopies and soil cover or by technical means to create micro-environments for the best possible growth and to prevent damage. Multi-storey cropping to make best use of light, shading, mulching, solar radiation for drying crops, irrigation, water harvesting and the many techniques that can be used for water and soil conservation all fit this agro-ecological principle.

4) Use prevention and safe treatment to cut damage by plant and animal pests and diseases. Farmers who use integrated systems and techniques that minimize the need for cures won't get caught on the pesticide treadmill. Researchers are developing integrated pest management, but so far it is aimed at decreasing the need for chemical pesticides for specific commodity crops. Food and other crops used in small-scale farming are still largely neglected by everyone - except farmers themselves.

Over centuries of experimenting, traditional farmers have developed many site-specific techniques - multiple cropping, trap crops, flooding, rotation, mechanical traps, plant-derived pesticides and medicines and locally adapted plants and animals with high resistance to prevailing diseases - to reduce damage from pests and disease. And their indigenous crops, trees and animals have additional advantages. Along with high resistance, they provide useful products and nutritious foods. Smallholders also exploit wild plants and animals. Although information on these indigenous, unconventional or underexploited genetic resources is sketchy, enough is known to indicate that they play a critical role in meeting the needs of people living under diverse, complex and risk-prone conditions.

Example: water buffalo health care

The water buffalo is highly appreciated by subsistence farmers because it provides traction, food and manure, as well as assurance for bad times. The animals are well worth extra care, and two farmer-innovators in the Philippines have come up with their own methods.

Low-external-input farming is labor rather than capital-intensive, and often involves the whole family. Here a Nepalese child transplants rice

Ramón Pelisco, a tenant farmer in Pamahawan, Leyte, who has one water buffalo with a calf, some chickens and pigs, makes his own herbal medicine to treat buffalo for severe diarrhea. He uses the herbaceous plant albahaka (Hyptis suaveolens), which grows abundantly in marginal areas. His procedure is to:

· take three fresh rootstocks of albahaka;
· wash them thoroughly with water;
· boil them in one litre of water until only about 375 millilitres of liquid is left;
· allow it to cool;
· put it into a 375-ml bottle, and give it to the animal;
· give a fresh solution every morning and afternoon for four consecutive days.

Albahaka also has other uses. It can treat diarrhea in humans and, when placed in chickens' nests, it minimizes lice infestation.

Tito Pael owns and farms seven hectares of sloping land in Altavista, Leyte. He grows coconut, coffee and maize and raises water buffaloes, goats, pigs and chickens. To deworm his buffalo calves, he extracts about 40 ml of pure coconut milk from finely ground coconut meat without adding water and mixes it with one egg from his chickens. He pours the mixture to the calf in the afternoon and then allows the calf to wallow the next day. If he sees no sign of internal parasites coming out he repeats the medicine, which is usually effective after two treatments.

5) Exploit complementarity and synergy in genetic resources. Agro-ecosystems with a high degree of diversity are likely to be more stable than those with only one species, and give the farmer more security - but only when the components are chosen well. It is important to recognize that simple diversity does not necessarily lead to stability and can even cause instability.

Functional diversity can be achieved by combining plant and animal species that have complementary characteristics and are involved in positive, synergistic interactions. The complementary characteristics may be different requirements in terms of light, nutrients, rooting depth, growing time or labor. The effects of synergy may be to improve growth through intercropping, to provide protection against damaging flows of water or wind or to produce waste products that serve as feed for other plants and animals. The result is improved stability and greater productivity.

When crops, trees, animals and humans are not complementary they may compete for land, solar energy, water nutrients, food or labor and influence each other for the worse by creating an unfavorable microclimate or transferring pests. Although competition cannot be entirely eliminated, it is minimal in good combinations of genetic resources. The farmer has to find the best possible balance between positive and negative aspects of the components - weighing loss of space, for instance, against creating a better microclimate or fixing nitrogen.

Example: crop-livestock-fish farming

Integrating crops, livestock and fish - a highly nutritious and valuable traditional food - in small-holder farming systems has ecological and economic advantages. By making full use of on-farm and adjacent resources, the systems work to conserve rather than to destroy the habitat. They are productive and profitable because they utilize wastes from one enterprise as inputs in another. And they exploit micro-environments within the farm system that add to farm productivity and security.

" Diversity does not necessarily lead to stability, and can even cause instability"

Farmers in Vietnam developed an effective system that combines rice, vegetables, chickens, cattle, fish and shrimp. They cultivate rice and raise shrimp in trenches, which also provide water to irrigate the vegetables grown in a mulch of rice straw on dikes made from trench mud. Immediately after trenching, they put chicken and cattle manure into the rice field trenches to promote phytoplankton blooms for the fish and shrimp to feed on. Although the shrimps' diet is primarily natural, they are also fed during their first two months with farm-grown by-products such as germinated rice grain, cassava flour, rice bran, coconut and groundnut oilcake and trash fish from the irrigation canals. Mango and eucalyptus branches are put in the trenches to keep out cattle and poachers and to provide the undisturbed habitat shrimp need.

The integration raises the system's overall productivity and lowers costs. The shrimp and fish eat rice weeds, thus cutting weeding expenses by a third. And chemical fertilizer input can be reduced by 30 per cent with no detrimental effect on rice production because animal manure and fish faeces fertilize the paddy. For more information contact: Clive Lightfood, ICLARM, MC P.O. Box 1501, Makati Metro Manila 1299, the Philippines.

The challenge is to discover which combination of plants, animals and inputs will improve security and productivity and conserve resources given the constraints of land, labor and capital. Multiple cropping, agroforestry and crop-livestock integration all help to exploit functional diversity. When exploited to its fullest degree, functional diversity provides complex, integrated farm systems that make the best possible use of available resources and inputs and thus limits the need for external inputs - to the benefit of farmer and field alike.

Coen Reijntjes, Bertus Haverkort and Ann Waters-Bayer are co-authors of "Farming for the future: an introduction to low-external-input and sustainable agriculture," from which this article is adapted.

Strength through flexibility

Diversity and flexibility
Diversification via new crops
A cure for sub-Saharan Africa
Integrating crops and livestock

Farmers' own experiments may lead the way to eventual food security

By William Grisley

No one disputes the need to find ways of farming that can meet rising demands for food without wreaking havoc on our natural resource base. But there's plenty of argument about what such high-output, yet sustainable production systems should look like. At one end of the spectrum is purely organic farming, at the other, the highly specialized, agrochemical-intensive monocrop and monolivestock systems of industrial agriculture.

Somewhere in between are alternative food producing schemes which emphasize intensification through both crop and livestock diversification and integration. These systems may well hold the best promise for the future, and today farmers across the developing world are continually experimenting with variations on the alternative theme. Their results can provide guidance - not only for the farmers themselves, but for researchers, development workers and government planners as well.

Diversity and flexibility

Before looking at some actual examples, it should be noted that the advantage of alternative production systems is that they are not set systems. Because of their diversity and flexibility, they offer vast opportunity for farmers in many agro-ecological environments - especially in countries where Green Revolution technologies are too expensive or inappropriate: The marginal production areas of Asia, Latin America and most of Africa fall into this category.

Diversified, integrated systems do require some inputs, and farmers must decide how much and what kind of internal and external inputs to use. If low levels of mineral fertilizers and crop and livestock protection chemicals are used, will production meet growing consumer demand? Will the systems meet farmers' objectives and be economically sustainable? High levels of external inputs will increase productivity, but will the systems still be economically and ecologically sustainable?

The type and operation of production system really depends on whether a farmer plans to produce or buy inputs. Deciding whether to produce or buy involves the economics of on-farm input production, and trade-offs between internal and external input use. On-farm production of organic fertilizer requires an abundant and reliable source of biomass and ample labor and/or mechanical power. If land fallowing and green manure crops are used to produce biomass, scarce cropland must be sacrificed and additional labor be used to harvest and incorporate the material. If livestock manure is available it requires more labor and management for collection, transport and incorporation.

Most farms in developing countries produce organic fertilizers, and farmers use complex cultural practices developed by long trial and error to control pests and diseases and guard against uncertain weather. They mix crop varieties and intercrop in the same field, relay crop, control crop residues and select disease-free seeds and plant cutting materials. They must accept the costs of foregoing crop production and increased labor and management, but most have few if any alternatives.

The economics of internal input production and use at farm level aren't favorable in some areas, and will become still less so as farm size continues to shrink and soil fertility decline. Internal inputs are expensive to produce and distribute, supplies are limited, and quality is uneven. There just isn't enough biomass material and labor in most areas to produce the organic fertilizer needed for high yields. Farmers' indigenous cultural control methods are also limited in supply and effectiveness, especially today when crops and crop varieties, livestock types and production methods are changing fast.

Diversification via new crops

But these changes can also work to the farmers' advantage. New crops and varieties that increase yields or reduce risks can help by allowing for greater diversification of cropping and fanning systems, while increasing overall sustainability. They can be incorporated directly into an existing system with minimal change and sometimes require few, if any, additional external inputs. For example:

· In Zambia, the introduction of soybeans is leading toward sustainability on small farms that traditionally used shifting cultivation methods to maintain soil fertility. More than 60 000 small-scale farmers are producing soybeans as a partial replacement for traditional food grain legumes, which are more susceptible to diseases and pests. Their risks are reduced, and their returns rise. Soybeans are now an important cash crop and are increasingly being used in the preparation of protein-rich foods for human consumption. Nitrogen fixation by soybeans also benefits maize, the basic food staple. Yields increase 20 to 30 per cent when maize is sown in a rotation with soybeans.

In the dry season, transhumant herders bring their cattle into farming areas to graze - and leave manure on - the harvested fields

· In Brazil, the release of new bean varieties has enabled both large- and small-scale farmers to increase productivity and returns. With the new varieties, bean yields rose by 26 per cent and gross returns by 16 per cent, and the cropping and farming system became more sustainable. Overall, the new varieties increased the value of bean production by over US$20 million annually.

· In Rwanda, a densely populated country desperately in need of increased food supplies, introducing climbing beans into areas where they were not traditionally grown made a big difference. Farmers realized a threefold increase in yield and a 500 per cent increase in gross margins by planting climbing beans instead of traditional varieties. By 1992, more than 160 000 farmers were using the new climbing bean production system. But the outlook is not entirely good. It took not only new varieties but also farmyard manure to produce the dramatic results, and fertilizer is a problem in Rwanda. The country lacks supplies of mineral fertilizer and manures are expensive and scarce. Constraints in the production of organic fertilizers and high import costs of mineral fertilizers could threaten the long-term sustainability and spread of the new climbing bean production system.

· In Vietnam, new maize varieties and technology that shortens the production cycle have enabled farmers to intensify their cropping system in the traditional rice-producing areas of the Red River Valley. During the cool, dry winter season large areas of unused paddy land are being sown to maize using an ingenious transplanting technology. By 1990, more than 250 000.hectares of winter crop maize were sown using the new technology. Yields were in the two-ton range, 30 per cent higher than the countrywide average. Here too, more mineral fertilizer was needed, but proved worth the expense. Excess maize supplies went into the production of pigs, which now provide large quantities of much-needed manure for intensive paddy rice production. With increased use of mineral fertilizer allowing for an increase in the production of organic fertilizers, the system as a whole is now more highly productive and perhaps more sustainable.

A cure for sub-Saharan Africa

Are high-yielding varieties and the use of mineral fertilizers a cure for the endemic low yields and increasing unsustainability of cereal production in sub-Saharan Africa? The Sasakawa-Global 2000 Project seems to think so, at least for selected areas. Results from farmers' fields are encouraging.

In Tanzania, high-yielding maize and sorghum varieties combined with applications of mineral fertilizer increased yields and gross returns by more than 200 per cent. The results with maize were similar in Zambia and only slightly less spectacular with maize and sorghum in Ghana, where yields rose by 100 to 200 per cent and gross returns by 60 to 900 per cent. Farmers in Togo and Benin, reported increases in maize yields of 50 to 100 per cent. High-yielding sorghum varieties and mineral fertilizers outdid traditional practices in the Sudan by more than 130 per cent.

"The path for action is to build on what farmers are already doing"

These results are dramatic and encouraging. But can resource-poor farmers afford the costs and bear the risks of using low-to-medium levels of mineral fertilizers? The project provided the credit and assured availability of seeds and fertilizer on a timely basis. Without direct project support of this kind there is concern that the high-yielding cropping systems introduced will not be viable. Yet, few alternatives for increasing cereal yields in Africa are readily available. Farmers in the project areas are unable to produce levels of organic fertilizer that can significantly increase crop yields. Land areas for production of biomass materials and labor are both critically in short supply.

Integrating crops and livestock

Many believe the key to development of a high-output, sustainable agriculture production system is integrating crop and livestock production on the same farm. Crops provide the feed for livestock, which, in turn, provide manure to maintain soil fertility. Simple in concept, but does this synergetic relationship actually work in practice?

· In the highlands of Kenya, favorable climatic conditions, a growing demand for milk and decreasing farm size led to the emergence of the zero grazing dairy production system. The system has allowed small-scale farmers to increase their incomes and thus their overall food security even as farm size drops. The farmers harvest cultivated napier grass every day to feed the confined dairy cattle. In theory, they are supposed to collect manure and return it to the grass plots to maintain soil fertility, but recent surveys have shown that only about one-half of all manure produced is actually going to forage plots. The farmers use the remainder on cash crops, principally horticulture crops and coffee, or simply leave it unused. Mineral fertilizers are used to make up part of the soil nutrient loss on forage plots, but soil mining is clearly occurring, and the long-run sustainability of the zero grazing system may be called into question as soil fertility levels decline further. Larger quantities of mineral fertilizers or less diversion of manure to cash crop production may be required to keep the system sustainable.

· In China, ammonia-treated straw technology is being used to produce cattle feed on both large- and small-scale units. Traditionally, large quantities of wheat straw were burned because of its low feeding value. Research and practice have shown that feeding of the straw once it is ammonia-treated is highly profitable. These profits can be significantly increased with supplementary feeding of cottonseed cake, a high-value protein feed that is locally produced. The manure produced by the cattle is then used on the winter wheat and summer cotton crops. This is another case where increased mineral fertilizer use contributes to an increase in organic fertilizer production.

· In Mali, livestock have been combined with cotton farming to form a profitable integrated system. The cattle make two important contributions. First, by using oxen for traction seed-bed preparation, planting and cultivation can be completed on a timely basis. Secondly, livestock manures are returned to cotton fields to supplement - but not replace - mineral fertilizer. Mineral fertilizer remains crucial because there are not enough livestock to produce the quantities of nutrients needed to keep the system at its current level of productivity and profitability.

These cases suggest the path for action is to build on what farmers are already familiar with and doing successfully. In many marginal areas, farmers are already successfully intensifying production through diversification of cropping systems and integration of crop and livestock systems. Even small-scale farmers will experiment with new technologies and readily utilize external inputs if they have the means and the returns are attractive.

But increased external input use does not by itself imply greater unsustainability. In fact, evidence suggests just the opposite when the inputs are properly used. This is an important point. Use of external inputs, especially new crops and varieties, mineral fertilizers and crop and livestock protection chemicals allows for greater flexibility in the cropping and farming system. This flexibility adds scope for higher production, profits and hence sustainability over the long term.

William Grisley is an agricultural economist and FAO consultant.