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Sustainable production systems

Over 400 million rural households are involved in agricultural production in the world, more than 90 percent of them situated in developing countries. These farm households are the principal decision-makers with regard to the use of crop and grazing land for food production, water for irrigation, energy for farm operations, and trees for fuelwood and construction. In the overall management of their production systems, farmers employ a complex mixture of traditional and new practices, the latter acquired through contacts with government research and extension services, international organizations and NGOs, and the private sector. Encouraged or discouraged by government policies and regulations, market conditions and price signals, farmers are making short- and long-term management decisions on crops to be grown, livestock to be kept, technologies to be adopted and investments to be made.

During the past three decades, production practices and systems have undergone profound changes, spurred on by the rapid increase in food demand, rural and urban population growth and technological change. While most production systems, ranging from shifting cultivation and pastoral systems to crop-based or mixed crop/livestock systems, are inherently sound and sustainable on an individual basis, their rapid multiplication and intensification may impose stress on the wider agro-ecosystem in which they are situated. An under-standing of complex production systems in relation to farm-household-environment relationships in areas with different resource endowments and agro-ecological conditions is important in the planning of sustainable development. (See panel)


The term LISA - low-input sustainable agriculture was coined in developed countries in the light of the environmental hazards caused by high or, more often, excessive inputs of fertilizers and pesticides. Not only do these overdoses constitute a threat to the environment, but they also represent a costly production factor. It is against this background that low inputs' were equated with sustainable agriculture'. In the case of industrialized countries, low inputs) actually means a reduction of the high levels current in modem' agriculture. It is misleading, however, to apply this same concept to agriculture in developing countries, where corresponding input levels are generally low. Here sustainability problems are generally those of depletion rather than of pollution. Loss of soil fertility results from a continuous mining of plant nutrients without their adequate replenishment. The age-old method of shifting cultivation - which made it possible to grow crops for a few years on nutrients derived from burning the forest - can no longer meet the demands of the present populations, let alone those of future generations.

Clearly, maximum use should be made of local resources such as crop residues, green manures and biological nitrogen fixation, but it must also be realized that residual organic matter cannot replace the harvest that is removed. Furthermore, large areas of acid soils in the tropics are inherently poor, so that even the organic matter they produce is very low in plant nutrients. Therefore, a combination of organic materials and mineral fertilizers, sufficient to replenish the plant nutrients removed by the crops and to enhance soil fertility, should be promoted.

FAO is actively supporting the development of Integrated Plant Nutrition Systems (IPNS) as an approach that is economically viable, environmentally sound and conducive to the urgently needed increases in food production. Naturally, IPNS has to be 'tailored' specifically to the resources available in different agro-ecological conditions, and also adapted to various farming systems. It would be preferable, therefore, to advocate BISA - a balanced inputs sustainable agriculture - rather than LISA. The term balanced' refers to an adequate and feasible combination of organic and mineral inputs, taking into account the availability of organic material and labour. Balanced' also points to the need to ensure a supply of the three basic plant nutrients, N. P and K, since organic material supplies only a substantial amount of N.

Integrated Pest Management (IPM) is another key component in sustainable agricultural systems. By keeping the use of chemical pesticides to a minimum and applying principles based on pest ecology (e.g., pest life cycles, predator/prey relationships), methods of cultivation and production can be adjusted so that farmers reduce their costs while avoiding the risks of excessive use of pesticides.

In the developing countries, LISA is often broadened to LEISA (low-external-input sustainable agriculture), to take account of the cost of purchased inputs which small farmers can afford rarely. The solution is not, however, to deny farmers the use of inputs. Such an attitude would be comparable to solving the problem of the hungry by recommending an even lower food intake. It is the task of public policy to create the economic motivation, and the infrastructure, necessary to give people access to the inputs they need

Since the early 1980s, FAO has focused on the development of agricultural production and farming systems in a holistic manner, and to this end a farming systems analysis and development approach was adopted in the Regular Programme and field work. Initial activities were targeted on the development of methodologies and procedures for the implementation of this approach in field projects and programmes Such methodologies include: production and farm data analysis, rapid rural appraisal techniques, analysis of indigenous production practices, the economics of cropping systems and the preparation of long term multidisciplinary programmes for on-farm technology testing. Emphasis is also given to training, through guidelines for seminars, informal workshops with universities, and the implementation of regional training programmes. Existing methodologies will be further developed to enable household and production systems to be integrated with multiple family objectives that include probability, equitability and sustainability. A new focus is given to the integration of traditional and modern farm and crop management practices and to the reduction of risks through on-farm and off-farm diversification of rural incomes, particularly in fragile ecosystems such as mountains, semi-arid areas and forests.

Forest resources

Environmental factors
Forestry for people
Research and cooperation
Sustainable forest use

Environmental factors

Much of the public concern about conservation of the environment and the depletion of natural resources focuses on large-scale deforestation, wasteful logging practices and excessive fuelwood consumption, particularly in the developing countries. In both developed and developing countries, the damage regularly caused by fire is recognized as a major threat to forests and the environment, especially in semi-arid tropical and Mediterranean areas. In developed countries environmental problems in forests are largely due to air pollution and acid rain, although more recently the threat of climate change has added a new dimension. (See panel)


A build-up in the atmosphere of the so-called greenhouse gases has been clearly documented over recent decades and a doubling of carbon dioxide (CO2) has been predicted by the middle of the twenty-first century. This may cause the earth's climate to become significantly warmer, with the major changes predicted to occur at higher latitudes. Changes in rainfall and rainfall patterns may also be expected.

The primary source of CO2 build-up is the combustion of fossil fuels, which account for approximately 5.4 billion tonnes of carbon per year. However, deforestation, which is eliminating considerable amounts of biomass, particularly in the tropical forest areas, also contributes to this build-up. The amount of CO2 thus released is estimated at 1.6 billion tonnes per year. On the other hand, natural forests, plantations, and trees in non-forest areas are capable of storing carbon as woody tissue. Considerable amounts of carbon may be absorbed through reforestation and afforestation and by increasing the stocking and production of existing forests. Worldwide, atmospheric carbon is estimated to be increasing by approximately 3000 million tonnes annually. The natural atmospheric pool of carbon is estimated at 700000 million tonnes. Although it would, in theory, seem feasible to capture a significant portion of the yearly increase through accelerated tree planting, capturing the full excess would require an unrealistic input of some 500 million hectares of high-yielding plantations in the immediate future. The initial cost would be some US$200-500000 million. As a measure of comparison, about 1.1 million hectares of plantation were established in 1980 in the tropical world, and although the rate of planting has increased significantly during the 1 980s, it falls far short of the total area needed to capture the excess carbon in the atmosphere.

It is clear that forestry can contribute substantially to capturing CO2, and it is therefore important to diminish the rate of deforestation; increase the rate of afforestation/reforestation; improve the management of natural generation of trees and shrubs; improve the management and productivity of existing forests, including intensive protection against fire, diseases and insect pests; and increase the conversion of mature wood to durable wood products.

FAO's contribution in this field lies first and foremost in its role as coordinating agency for the implementation of the Tropical Forests Action Programme (TFAP) the general aim of which is to strengthen and harmonize international cooperation in tropical forestry. It constitutes a forestry response to climate change at national as well as regional and global levels. It promotes the sustainable management of tropical forests, afforestation/reforestation and tree planting, all of which are key components in limiting the amounts of carbon dioxide present in the atmosphere.

In its publication Climate Change and Global Forests' FAO reviewed the status of knowledge as of 1989. It is recognized that predictions on future climate change merit concerted action by the world community viz. dissemination of information on the role of forests as sinks and sources of carbon dioxide; protection and buffering of forests arid trees against destruction; potential effects of climate change on the distribution and productive capacity of forest ecosystems, and adoption of global and national strategies aimed at a better scientific understanding of the processes involved. However, it is also recognized that massive reforestation for the sole purpose of sequestering CO2 cannot be justified at the present time.

Natural forests are essential to life and human well-being. Being renewable, and for as long as they are conserved and managed sustainably, they can satisfy the large, diverse and often conflicting demands which people make on them. They play a crucial role in regulating the atmosphere and the climate. They absorb solar radiation, influence the hydrological cycle and moderate local climates. Forest cover on steep and fragile mountain slopes moderates surface run-off and soil erosion, thereby reducing downstream siltation of reservoirs irrigation systems and fish habitats, and the threat of flooding Of croplands and homes Similarly trees and woody vegetation play a major role in arresting land degradation and controlling wind erosion and desertification in dry zones.

Forests are major stores of carbon They provide raw material for income-earning activities by local and national communities and a variety of products used by forest dwellers and rural people for food, fuel, fodder and medicines. At the same time, they conserve genetic resources and important wildlife habitats. An important consideration of natural forest management is to ensure that selected areas are preserved on a scale that can maintain biodiversity and take into account the interests of forest dwellers.

FAO regularly monitors world forest resources. In 1980, in collaboration with UNEP, the Organization carried out an assessment of tropical forest resources. A further global assessment is just being completed with 1990 as a reference year, and preliminary results show the rate of tropical deforestation to be 17 million hectares per annum, thus confirming it as a major environmental problem.

In addressing the impact of forestry on the environment as well as the influence of the environment on forests, FAO concentrates on the environmental influences of sound forest management and utilization. Forest management includes a range of interventions from complete protection to management of timber and other forest products in three basic production systems: natural forests, plantation forests and agroforestry. FAO focuses on two main areas. The first entails providing assistance to Member Countries in the management of their tropical high forests, with special attention to sustainability and multiple use. In support of this, the Organization has published reviews of management systems in Africa, Asia, and Latin America and the Caribbean. FAO has also published guidelines for the integration of genetic resource conservation into productive forest management systems. A second area is the management of woodlands and shrublands in dry zones, with people's participation and the integration of livestock activities.

Plantation forests serve primarily to rehabilitate degraded lands and to produce wood for fuel and industrial purposes. While they may have a low amenity value, well-planned and managed plantations, making use of suitable species matched to the requirements of sites and with the objective of serving clearly defined markets, can have a positive impact on the environment. In arid and semi-arid areas special attention is devoted to combatting desertification (See panel)


The consequences of uncontrolled land use are often disastrous. Deprived of their vegetation cover, the shallow soils on tropical hillsides may be stripped away during a single rainy season. Nowhere is environmental stability more critical than in the arid and semi-arid regions of Asia, the Middle East and Sub-Saharan Africa. In these dry lands the heavy demand for fuelwood, the overgrazing of livestock and the clearance of marginal lands for dry farming of cereals leads inevitably to extension of the desert.

Reforestation projects using drought-resistant tree species can stabilize and enrich impoverished soils, while shelter, shade and improved water retention can create conditions suitable for sustained agriculture. The trees provide fodder for livestock, fuelwood and building timber, and even cash crops. Training and extension activities associated with the conservation measures encourage the gradual settlement of nomadic rural populations.

FAO has helped many countries to develop strategies for combating desertification. Projects on sand dune stabilization have been undertaken in southern Morocco, coastal Senegal, Mauritania and Somalia. Particularly important is the assistance provided to the eight countries of the Interstate Committee for Drought Control in the Sahel (CILSS) in their major programme of creating village fuelwood plantations in that drought-ravaged region.

An important aim in arid zones is to encourage greater diversification of production, particularly for the provision of fodder and wood, through integrated agro-sylvo-pastoral systems. The large number of FAO-assisted rangeland management projects operating in North Africa and the Near East provide a wealth of new information and experience in this respect. This is being passed on through workshops and training courses to develop skills in fodder, fuelwood and shelterbelt provision, and in many other aspects of arid-zone management and integrated rural development.

Forestry for people

Agroforestry and tree planting outside forests can help to restore degraded lands, rehabilitate salt-affected land, stabilize sand dunes by tapping moisture and nutrients in the deep soil layers, provide windbreaks and shelterbelts, help protect and improve crop yields, and provide sources of fodder, fuelwood and green manure. In agroforestry, woody perennials are integrated with crops and/or animals on the same land management unit in order to obtain the best returns on a sustainable basis. Other FAO initiatives include provision of seed through genetic improvement work, the installation of seed storage facilities, training and networking, and the introduction of multipurpose species and dryland species particularly in Africa.

Planting trees helpsrestore degraded lands and stop desertification. In Bangladesh, schoolchildren participate in a community forestry programme.

One of the essential objectives of sustainable development is the attainment of economic viability through sound land use. Providing employment and income to rural people through sustainable forest exploitation offers a more environmentally sound alternative than clearing the forests for non-sustainable forms of agriculture such as shifting cultivation or cropping on fragile and marginal soils. Pilot studies in tropical countries have demonstrated that closed forests can be managed sustainably for timber and other forest products while maintaining environmental benefits and conserving irreplaceable genetic resources. However, a key factor is the political will of countries to institute effective programmes. Constrained by serious socio-economic and institutional difficulties, many developing countries are unable to support the degree of commitment required. The implementation of the Tropical Forests Action Programme and the provision of assistance to countries in policy formulation, strategy and planning will help consolidate their capabilities in forest management.

Public and political reaction to forest operations deemed detrimental to the environment is becoming more severe - a tendency evidenced by recent proposals for boycotting the use of tropical wood, and by proposals made in several developed countries to ban imports of tropical timber unless it can be proved to have come from a forest managed on a sustainable basis. However, blanket bans are largely ineffective: they are even likely to aggravate deforestation as local communities and national planners will look for more remunerative alternative land-uses. A better conservation strategy is to increase the economic benefits gained from using the forests and to strengthen the institutional capacity needed to ensure sustainability of productive forest management. Forest products harvesting, transport and processing need not cause serious environmental damage, and can contribute significantly to the pressing and legitimate needs of countries to utilize this natural resource for development. Proper monitoring and control can ensure that appropriate harvesting and road construction techniques are used, and that timely action is taken to regenerate harvested sites. FAO is giving particular attention to ways of improving logging practices so as to reduce waste, environmental damage and loss of the forest's productive capacity.

Forest resource appraisals are part of FAO's mandate. This map and table, based on data collected for the Forest Resources 1990 Project, give preliminary area estimates for countries lying predominantly in the most tropical zone.

Research and cooperation

The effects of air pollution and acid rain are so far evident mainly in temperate and boreal forests. It is estimated that almost 15 percent of the growing stock of 17 European countries has been moderately to severely damaged by air pollution and that the decrease in productivity in those forests is related to either location-specific or transboundary pollution. In the first case, notably in the immediate vicinity of polluting industries, there is a clear causal relationship between forest die-back and measurable chemical changes in the environment such as increased soil acidity. Transboundary pollution, a term often used for air pollution that cannot be readily attributed to a specific source, is also leading to measurable changes in soil acidity. Many European countries have already started nationwide monitoring systems to discover the extent and trends of forest decline and to gain more knowledge of the causal relationships involved. In addition, national and international legislative action has been taken to control and reduce harmful emissions.

There is an urgent need to greatly expand our knowledge of the forest resource and its values, and to assess more accurately its potential to meet the multiple demands for forest products on a sustainable basis. A much wider application of sound forest management practices is needed and, where feasible, there must be an increased role for trees on agricultural lands, particularly in marginal areas.

FAO has given strength to the concept of sustainable development in its work with other international agencies such as UNEP (forest resources assessment and conservation of genetic resources); the International Tropical Timber Organization (ITTO) (preparation of guidelines for sustainable forest management and plantation development; IUCN (national systems of protected areas and environmental management); and WRI, co-founder of the Tropical Forests Action Programme. Further work is being carried out in FAO to examine ways and means by which environmental and sustainability considerations could be integrated into all stages of the project planning and implementation cycle.

The Tropical Forests Action Programme (TFAP) has become an important means of providing policy advice and planning assistance to developing countries in order to combat forest degradation and to promote sustainable forestry development. The TFAP aims to establish a process through which all interests, public and private, cooperate in the sustainable management and utilization of forest and tree resources with the support of the international community.

Sustainable forest use

Sustainability cannot be achieved without the intimate involvement of other sectors, such as agriculture, if wasteful and unplanned expansion of other land uses onto forest lands is to be avoided Key policy aspects which require concerted attention are land use and tenure, national financial incentive mechanisms, forest industries development,. institutional reforms and people's participation. Local needs for forest goods and services must also be given a much higher priority.

Before more forest land is considered for allocation to agricultural purposes, attempts must be made to increase agricultural productivity on existing farm and range lands and to ensure that sustainable agriculture will be possible on any land that is converted from forest. Governments need to develop land use policies aimed at achieving efficient use of land while striking a balance between environmental requirements and the pressing needs for increased food production and income generation.

If forest resources are to be used sustainably they mud be treated as a capital asset in the national accounts.

If forest resources are to be used sustainably they must be treated as a capital asset in the national accounts. Government pricing policies must reflect the true value of forest resources, including the full costs of establishing, regenerating and managing the public forest estate. Most developing countries are forced to maximize the use of their land and natural resources to support economic and social development and to pay their debts. In this respect, the potential for environmentally sound use of trees and forests is important in recent years however, governments have tended to neglect the forest industry sector in order to address short-term and more politically expedient concerns. Wherever feasible, the potential for development of appropriate forestry enterprises should be pursued by developing countries at all levels, from small-scale local industries to larger forest industries.

Wild animals are one of the most important direct contributions of the forests to the well-being of local people. Major efforts should be made to assess, manage and utilize these resources with a view to their inclusion in national economic development plans. Forest management should include the application of techniques designed to increase the sustainable yield of meat from forest-based animals. As such an approach could lead to significant improvements in forest development efforts, not only those aimed at commercial production but also those concentrating on conservation of the resource base. FAO is actively engaged in developing the potential of wild animals to contribute to rural economies and to improving the nutrition levels of rural people. (See panel)


With the domestication of animals and the development of settled agriculture, humans gradually moved from complete dependence to partial dependence on wild animals for meat. Nonetheless, in all cultures of the modern world, wherever people eat meat, there is still a significant demand for wild game: in Sub-Saharan Africa, its proportion of total protein supplies is exceptionally high.

There is little information on the nutritional value of traditionally preserved game meat. However, there is evidence that when fresh, game meat compares favourably with domestic meat in terms of mineral, vitamin, fat and protein content. Game meat is leaner and the yield from wild animals is similar to or even exceeds that of domestic stock. Perhaps the most important measure of the local value of game meat comes from studies that have asked people what they value most from forests. Many of those surveyed considered the worst impact of forest conversion to be the loss of game meat in the area.

Many of the species important as food are taken for granted: they are over-exploited and their habitats abused. This leads to local elimination of significant resources. For many, income from hunting is an essential part of a subsistence economy. However, hunting tends to become excessive and requires management if the resource base is to be maintained.

Both domestic stock and wild animals convert vegetable matter to meat, but vested interests invariably favour the former. While the meat production potential of wild animals compares favourably with that of livestock, indigenous animals continue to be deliberately exterminated in favour of livestock. The elimination of wild animals does not, however, lead to optimal utilization of range. Domestic animals are selective in their feeding and not all range plants are utilized. A variety of animals with complementary feeding requirements can be much more advantageous. Thus, suitable mixes of domestic and wild animal species in combined production systems have economic and ecological advantages.

Management systems and technologies should be developed to improve such integration and increase total meat production. Both kinds of meat are in demand, but the additional income for sport hunting and recreation is an added benefit.

In developing countries, attempts to integrate wild animals into cropping systems are rare. Wild animal production can be more easily integrated with tree crops than with large-scale food crops, which replace all existing vegetation, and in the latter case, it is important to maintain suitable wild animal habitats by creating hedges, windbreaks and shelterbelts.

Although many governments have resorted to law enforcement to control wildlife exploitation, such laws are commonly disregarded where resources and short-term survival are linked. Conservation for its own sake does not work. There can be no long-term future for wildlife or protected area management where local people are antagonized. Instead, they should benefit from the management of these resources and have a vested interest in their conservation as sources of food and income. The requirements of tourism and meat production need not be mutually exclusive.

If rural people do not perceive that sustainable forest management is to their advantage, no amount of government decrees or plans will achieve the desired effect. People's participation in decision-making and management, and in the sharing of benefits, should therefore be given high priority in forestry development. FAO has carried out a wide variety of studies and demonstration activities to develop participatory approaches and mechanisms for the management, production and utilization of renewable natural resources by rural people themselves. The 'Forests, Trees and People' programme aims at the appropriation of forest and tree-related practices by rural people so that forestry is a real benefit to them, not only through physical benefits but also through environmental and cultural outputs and services.

An important aspect of the contribution of forests to the environment and to people's welfare is the role of trees in urban and pert-urban areas. There is a growing demand in urban societies for forested or tree-covered spaces and FAO, recognizing this need, has included urban forestry in its Programme of Work for 1992/93.

Many environmental concerns related to forestry are local in nature. However, the increased international concern over global environmental issues calls for more action at the international level and on a global scale, by both developed and developing countries. FAO has assisted the international community to reach a consensus on a set of principles for the management of forests. For the present, 'a non-legally-binding authoritative statement of principles for a global consensus on the management, conservation and sustainable development of all types of forests' has been worked out within the framework of the preparatory process for UNCED. These principles will have to be considered alongside those embodied in existing and proposed international agreements, including the International Undertaking on Plant Genetic Resources, the proposed International Convention for the Conservation and Utilization of Biological Diversity and the proposed Framework Convention on Climate Change.

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