Viewpoints to consider... Issues to explore

Roger Leakey has chosen excerpts from four books - their subjects ranging from Africa to the Amazon, and local knowledge to ecological restoration - that illustrate the breadth and depth of agroforestry, and give a taste of recent trends in theory and research./GJM

Cultivating knowledge

For thousands of years farmers have been adapting crops to diverse environments and experimenting with and developing new varieties. The interaction between people, the environment and their food crops has provided the world with a wide range of crops and a remarkable diversity of varieties within single crops… These interactions have also resulted in a human capacity to further develop crops through a process of continuous adaptation and experimentation…

Agricultural modernisation, commercialisation, intensification of production, and destruction of habitats are promoting genetic erosion, and threatening both this diversity of local crops and the processes which sustain it. This also results in a loss of farmers’ knowledge of crops and of their capacity to maintain and develop diversity. Institutionalised crop breeding relies to a considerable extent on landraces originating in the major centres of diversity in the South. The genetic material available for this modern crop breeding is therefore being diminished. While genetic erosion threatens the world’s base of food plants, the erosion of knowledge threatens the human capacity to maintain and further cultivate this diversity…

[This book] examines the threat to global agricultural diversity and the implications for agroecosystems. It addresses the need to develop appropriate research and development strategies which build upon the capacity of farmers to experiment with crops, and the knowledge they have acquired of diversity. Farmers’ experiences with diversity provide an important framework for the development of conservation strategies…

A challenge facing the agricultural sciences is to develop methodologies and institutional forms, which will enable farmers to build upon their skills in adapting crops to the environment... In recent years there has been growing realisation that human activities contribute considerably to genetic diversity. Conservation strategies can benefit from building linkages with the crop development strategies of rural people. Farmers have created and managed environments where plants could evolve under selective pressure. These environments differed from those occurring in those ‘wild’ environments only marginally disturbed by people. They have adapted their farming practices, crops and varieties to different environments, thus creating a diversity of agroecosystems, crops and varieties. Such ecological and genetic diversity provides security for the farmer against pests, disease and unexpected climatic conditions…

In contrast, modern agriculture is largely concerned with standardisation and attempts to homogenise the environment to achieve optimal production conditions... The development of more environmentally sustaining technologies requires the transformation of these strategies. Greater emphasis needs to be placed upon preserving the diversity of crop varieties, crop species, agroecosystems, regions and societies…

Recent concerns with the environment and natural resources management… have resulted in a growing emphasis on developing research approaches which build upon the capacities of farmers to engage in experimentation and adapt technologies to local needs. These approaches place a strong emphasis on the local knowledge of farmers, both as an entry point for new research and as a relevant resource which complement shortcomings in scientific approaches to interaction with the environment…

Recent interest in local knowledge of genetic resources needs to be treated with caution since, in this age of biotechnology, control over diversity in plant genetic resources offers the promise of considerable wealth and economic power to the agribusiness world. This is reflected in the recent rush to establish patents over life forms. In this struggle the odds are very much stacked against small farmers. Through control of world legal, market and political knowledge, agribusiness interests are likely to be able to use research into local knowledge for narrow commercial interests, rather than for the long-term development and environmental needs of marginalised farmers. There is the risk that discovery, while potentially progressive, can precede exploitation…

An adequate response to this challenge requires that, beyond developing methodologies and institutional approaches for building linkages between farmers and researchers, research addresses the policy dimension of crop development. This requires the elaboration of a critique of the institutional and commercial settings of research, a critique that has the potential to influence policy frameworks and promote change and reform in such areas as legislation, intellectual property rights and agricultural research management. This critique must also create pressures for technology institutions to become more transparent and responsive to the needs of the majority of farmers. At the same time, local organisation needs to be strengthened in order to increase the capacity of farmers to manage local development, to analyse the wider environment in which their crop development activities unfold, and to exercise pressure over institutions and policy makers. These are challenges which can only be met when socio-cultural, biological and political economic perspectives are combined consistently and logically.

De Boef W., K. Amanor. and K. Wellard, with A. Bebbington 1993. Cultivating Knowledge: Genetic Diversity, Farmer Experimentation and Crop Research. London, Intermediate Technology Publications. This book presents a number of case studies from Africa, Latin America and Asia that examine a suite of issues surrounding the repercussions of the expansion of agribusiness on the interests of small-scale farmers. Contact: Mr. Guy Bentham, Sales and Marketing Director, Intermediate Technology Publications Limited, 103-105 Southampton Row, London WC1B 4HH, UK; Tel. +44.171.4369761, Fax +44.171.4362013, E-mail itpubs@itspubs.org.uk,
Website http://www.oneworld.org/itdg/publications.html

Rehabilitation of degraded pasture in Amazonia

The 6.2 million square kilometer Amazon Basin is the world’s largest remaining preserve of tropical forest and a large C [carbon] pool. By 1988 … development strategies aimed at settling the landless poor and integrating Amazonia into the Brazilian national economy had led to the deforestation of between 20 – 35 million hectares. Of the cleared areas, the dominant land use was, and continues to be, low productivity cattle pasture, over half of which is thought to be in some state of degradation. There are an estimated 20 – 35 million hectares of abandoned pastures in the Amazon basin, and these abandoned lands may take 50 to 100 years to develop into mature secondary forest. Meanwhile, local farmers and new migrants to the Amazon continue to clear primary forest for transitory food, cash crop, and pasture systems, and eventually abandon the land as it loses productivity. Rehabilitating the productivity of these abandoned pasture lands has the potential to convert large areas from sources to sinks of C, while providing for the well-being of people in the region and preserving the world’s largest undisturbed area of primary tropical rainforest.

Agroforestry systems are well suited to improve land productivity and conserve natural resources in the Amazon. To rehabilitate the productivity, C sequestration, and biodiversity of the huge expanses of low biomass, abandoned pastures in the Amazon, we have designed and are testing four agroforestry multistrata systems (sequences of crops, pastures and trees). The systems were designed on the basis of an intensive farmer survey and the results of two decades of soil/plant research in the Amazon. A key specification of the design was to optimize both biological productivity and economic returns, while minimizing nutrient losses through a combination of biological and modest chemical inputs…

The dominant vegetation at the site is moist, evergreen forest. The soil is a Xanthic Hapludox and the rainfall is c. 2800 mm yr-1. The degraded and abandoned pasture vegetation consists of 39 species representing 34 genera and 23 families. The most abundant tree species were Laetia procera, Vismia amazonica, Vismia lateriflora, and Visma cayennensis. The most frequently encountered herbaceous species were the competitive forbs Borreria verticillata and Rolandra fruticosa. Many of the species and genera detected at this site have been reported in species inventories of abandoned pastures at other locations in the Amazon. Total above ground biomass on the abandoned pastures corresponds to about 5% of the biomass reported for primary forests on Oxisols in the Amazon and less than half of that reported for other secondary forest regrowth of similar age. This is a reflection of moderate to high site disturbance intensity which hinders successional regrowth when the pastures were abandoned…

Four agroforestry systems were developed as promising prototype systems for rehabilitation of degraded pastureland in the western Amazon. Two agrosilvicultural (trees and crops) and two agrosilvopastural (trees, crops and improved pasture) systems were established. The treatments imposed were designed to provide comparisons between moderate and intensive land use within each of these agroforestry systems. Tree species comparisons in each option were chosen on the basis of local farmer practices and for specific uses, e.g., as live fences (Gliricidia sepium), fruit (Theobroma grandiflorum, Inga edulis, Bactris gasipaes, Bertholettia excelsa, Malphigia emarginata, and Carica papaya), firewood (Inga edulis) and timber (Swietenia macrophylla and Schizolobium amazonicum). Planting density and pattern for each tree species involved considerations of canopy architecture and whether competition among species was a desirable trait. Peach palm, for example, was planted at high density because half of the plants are harvested every 12-14 months for heart-of-palm. Annual crops (Oryza sativa, Manihot esculenta, Zea mays, Vigna unguiculata) were planted during the initial periods of tree and pasture establishment, but were eventually phased out of the systems by tree shading or competition with grasses and forage legumes. Animal grazing of the grass-legume pastures in the agrosilvpastoral treatments began in 1996…

The systems are now 6 years old and all the components have been installed. In the first two years, the high input agrosilvopastural system produced 2.5t ha-1 of maize and cowpea and 20t ha-1 of cassava. The agrosilvicultural systems produced 0.4t ha-1 of rice, 14t ha-1 of cassava and 20.1t ha-1 of fruit (Theobroma grandiflorum, Malphigia, Eugenia, papaya, and passion fruit). The high market value of the fruits makes the latter system more attractive for farmers.

Weed management was crucial to ensuring successful establishment and growth of the crop and fruit species. On average plots contain 1.4t ha-1 of weeds containing 22kg N, 2kg P, 22kg K, 8kg Ca and 4kg Mg ha-1. Weed biomass was applied as mulch to fruit trees so that the nutrients released from the weeds would partially offset the cost of weeding. The diversity of plants appearing in the agroforestry plots was double that found in the abandoned pasture controls. We encountered 65 species distributed across 40 genera and 18 families.

The spatial arrangements in the agrosilvopastoral systems successfully inhibited the attack of Hypsipylla grandella on mahogany and resulted in clean stems of 6 m in three years before attacks were observed. The pole tree Columbrina glandulosa proved to be an excellent species for multistrata systems, reaching 10 m in 3 years. All plant species responded positively to added nutrients. There was a dramatic shift in functional groups of soil macrofauna in the agroforestry systems compared to the abandoned pasture controls. Earthworm population increased significantly in the system containing peach palms. Measurements of total nutrient and carbon stocks, green house gas fluxes, macrofauna dynamics and system productivity and profitability are in progress.

Fernandes E.C.M., R. Perin, E. Wandelli, S.G. de Souza, J.C. Matos, M. Arco-Verde, T. Ludewigs and A. Neves. 1999. Agroforestry systems to rehabilitate abandoned pastureland in the Brazilian Amazon. Pages 24-26 in F. Jiménez and J. Beer, editors, Multi-strata Agroforestry Systems with Perennial Crops. Turrialba, CATIE. This book presents the proceedings of a recent conference held at CATIE and provides much current information about multistrata systems, especially in Latin America. Contact: Ms. Laura Coto, Head, Orton Memorial Library, CATIE, 7170 Turrialba, Costa Rica;
Tel. +506.5561016, Fax +506.5560914,
E-mail lcotor@catie.ac.cr,
Website http://www.catie.ac.cr

Farms, trees and farmers

[In this book] we consider whether the patterns of tree growing behaviour that have been observed and analysed enable the formulation of stronger hypotheses about the role of trees and tree products, and about requisites for tree growing by farmers, and provide a more focused starting point for the process of defining the need and potential for policy, programme or project interventions… As the variety and complexity of the array of different roles played by trees in rural livelihood strategies becomes clearer, it is evident that there are few answers of general application…

As has been demonstrated in nearly all of the situations examined here, there have been, and continue to be, significant changes in the way farm households employ trees and tree products over time, with many of the changes being both substantial and rapid. Furthermore, the general trend in different regions experiencing agricultural intensification has been towards more intensive tree planting… Production and use of tree products at the village level are in practice often embedded in complex resource and social systems, within which most of the factors that affect our ability to intervene with forestry solutions at the village level are of a non-forestry nature. They are primarily human factors, connected with the ways the people organize the use of their land and other resources…

Where trees do serve a purpose in terms of household objectives, they will often contribute to meeting environmental and distributional concerns as well. But it needs to be clear that any broader resource and environmental benefits that may accrue from tree stocks emerge as a by-product of, and are subordinate to, farmers’ pursuit of their livelihood goals…

Tree planting can be explained as being one or more of four categories of response to dynamic change:
• to maintain supplies of tree products as wild sources decline due to deforestation or loss of access
• to meet growing demands for tree products as populations grow, new uses emerge or external markets develop
• to help maintain agricultural productivity in face of environmental degradation
• to contribute to risk reduction and risk management in face of needs to secure rights of tenure and use, to even out peaks and troughs in seasonal flows of production and income and in demands on labour; or to provide a reserve of biomass products and capital available for use during times of stress or emergency…

With most situations experiencing reduction in access to off-farm supplies, growing demand, declining site productivity and increased exposure to risk, it should not be surprising that tree planting activity does increase as agriculture and landuse become more intensive. Though it would be incorrect to assume that this always happens, there is a general progression towards more planted trees as agriculture and pressures on land intensify, and existing trees diminish, within most systems. It is also clear that a substantial part of the increase in farm tree growing reflects the fact that, as pressures on their labour and other resources increase, many farmers are responding by reducing the intensity of use of their land, or part of their land. Faced with shortages of labour and other inputs to agriculture (compost, fertilizer, etc.), farmers abandon their poorer or more distant lands, or put them under less intensive use, in favour of concentrating the use of available inputs on the more favourable sites…

It has long been argued that private growing of such a long-gestation crop as trees will occur only if there is security of tenure over the land on which they are to be planted. However, the thesis that this degree of security can only be provided by private ownership of the land has increasingly been questioned. The occurrence of privately planted trees in a wide variety of tenurial contexts indicates that such generalizations are not necessarily accurate… In Eastern Africa, the most important factor affecting tree growing appears to be the existence or absence of rights of exclusion, in particular exclusion of grazing on the household’s fallow fields. Where this is discouraged, because livestock management is important, or where it cannot be enforced, tree growing is unlikely to take place. Where farmers can exercise this degree of control, economic factors are probably more important than land tenure in determining decisions about tree growing… Where governments intervene to tighten control over forest resources on public land, this can undermine or eliminate local rights of use, and can accelerate the shift towards greater dependence on privately planted resources…

As agriculture shifts from a predominantly subsistence basis to greater involvement in market transactions, tree growing at the farm level becomes exposed to a number of influences. Markets for factors of production affect the availability and cost of land and capital, and choices between activities that draw upon these factors in different amounts and proportions. Access to purchased inputs such as fertilizer can permit shifts away from extensive land uses involving trees. Access to market outlets for tree products can extend the range of the farm household income generating options… Local markets for fruits, fuel, poles and other tree products develop, often first as barter trade, as shortages emerge, as increasing demands on the time of women leave less time for gathering what is needed to meet household needs, and as rising incomes allow some the option of purchasing rather than gathering or growing.

Arnold J.E.M. 1997. Retrospect and prospect. Pages 271-287 in J.E.M. Arnold and P.A. Dewees, editors, Farms, Trees and Farmers: Responses to Agricultural Intensification. London, Earthscan. This book brings together results of the work of a number of researchers who have examined the changes in tree management taking place in different parts of the world. Contact: Earthscan Publications Limited, 120 Pentonville Road, London N1 9JN, UK;
Tel. +44.171.2780433, Fax +44.171.278142,
E-mail earthinfo@earthscan.co.uk,
Website http://www.earthscan.co.uk

More people, less erosion

The view which this book takes of the environment–population debate differs from most others… We are seeking to explain why environmental recovery has succeeded, and the role in this of various actors, including, very importantly, the local inhabitants…

Some have taken the view that rapid population growth leads inevitably to increased poverty and natural resource degradation, through, amongst other things, land scarcity, falling fallows, deforestation, cultivation of marginal lands, conditions favouring large families and underdeveloped human capital… Our view has been conditioned by two factors. The first is the evidence we have amassed of the reversal of degradation in Machakos (Kenya) of rising productivity and living standards, and successful exploitation of lands previously deemed unfit for agricultural use. The second is the knowledge that population growth has been accompanied by specialisation, diversification of the economy and an increased rate of technological change, which has outpaced any threat to the depletion of resources. We therefore see, in this instance, population increase as positive, not negative…

In pursuing improvements in their livelihoods, the Machakos people have not destroyed their environment, despite their poverty and the riskiness of their semi-arid climate. That there was a real environmental problem in the 1930s has been shown in the photographic record. The change that has taken place was not due to changes in rainfall systems. Soil erosion has been eliminated on much cultivated land and there are signs of improvements in grazing lands. The spread of population and stock into agroecological zones 5 and 6 has not so far resulted in any irreversible loss of productive capacity, although there has also been an increase in the woodiness in the vegetation. Some areas formerly under natural vegetation are now conserved and productive arable fields, as are areas that were formerly degraded and almost bare grazing lands. The fuel shortage has never reached the often-predicted crisis point and there are now more trees grown for many different purposes. Agricultural output on a per head and per hectare basis has increased in value substantially, with food output tracking population growth. The only area where improvement in resources is in doubt is in the maintenance of soil fertility levels where we have been unable to reach firm conclusions. However, we have shown that fertility depends on management. Agricultural incomes are now supplemented by much more non-farm work than was formerly available. The huge growth in the output of non-subsistence products has developed jobs in marketing, processing and the satisfaction of new consumer demands…

Conservation has been the result of the farmers’ own investments of labour and capital into land improvement and development, at times assisted by external advice and capital. The physical changes have been accompanied and underpinned by changes in Machakos society, which developed its knowledge and management capacity, and which broadened the basis of local leadership. This enabled it to select, evaluate, develop and use different technologies, and to react to changes in the markets for its labour, land, and feasible outputs… We accept the view that technological change is both impelled by population growth and facilitated by the increased human interaction to which it gives rise. We see new technologies as coming from many sources, including, importantly, the farmers themselves…

We regard the availability of capital and security, knowledge of opportunities and technologies, economic incentives and access to jobs, land, or markets, as necessary conditions to enable people to respond to population pressure either by out migration to seek jobs, or by settlement of new lands, or by intensification of agriculture and the diversification of the local economy in situ…

The switch to farm-tree promotion that took place under the Machakos Integrated Development Programme recognised the value placed on privately owned economic trees. A quiet revolution in farm tree management has increased the value of output per hectare and is consistent with the imperative of intensification…

The discussion here has shown the importance of attention to population density and to access to markets and knowledge, which increasing population density helps to facilitate. What is appropriate at a high level of population density may be a misuse of scarce labour resources at low population densities. At low densities, population growth assists development, by providing labour and facilitating access to markets and to information. In Machakos, rising output volume has accompanied a rise in population densities to over 400 km2 in the higher potential areas. The people who have the best knowledge of the changing costs of land and labour and of the market opportunities for products and labour are the inhabitants.

Tiffen, M., M. Mortimore and F. Gichuki. 1994. More People, Less Erosion: Environmental Recovery in Kenya. Nairobi, African Centre for Technology Studies and London, Overseas Development Institute. Based on a field study of landuse change in Machakos District in Kenya, this book comprehensively summarizes the results from a project by ODI and the University of Nairobi that illustrates population growth need not have negative impacts on either peoples’ livelihoods or the environment. Contact: ODI, Portland House, Stag Place, London, UK; Tel. +44.171.3931600, Fax +44.171.3931699,
E-mail odi@odi.org.uk