The Potential of
Agroecology to Combat Hunger in the Developing World
Miguel A. Altieri
Department of Environmental Science, Policy and Management
University of California at Berkeley
Peter Rosset
Institute for Food and Development Policy/Food First
Oakland, CA
Lori Ann Thrupp
World Resources Institute
Washington, DC
Hunger and malnutrition affect nearly 800
million people in the developing world. By and large those problems
are not due to an absolute scarcity of food, however, but to the more
complex issues of who grows food and how and where it is grown, how
it is distributed, and finally, who has access to it. In this complicated
web of causality, inequality is the outstanding driving force behind
hunger. Misuse and over-exploitation of natural resources are other
central factors underlying food gaps. Any technological policy for rural
and agricultural development then, must be judged on, among other factors,
whether it tends to increase or decrease inequity in the distribution
of and access to resources and food, and whether it ensures sustainability
of resource use.
Proponents of a second Green
Revolution (GRII) generally argue that scarcity and low agricultural
productivity cause food insecurity and will also aggravate global hunger
in the future. Those holding this perspective usually believe that "overpopulation"
and food scarcity cause hunger, and likewise, dwell on aggregate global
food production/consumption figures to justify GRII, but seldom look
at distribution and disparities at the local or regional level. Therefore
they propose a new wave of agricultural intensification based on stepped
up fertilizer and pesticide use in Africa and parts of Latin America,
bioengineered crop varieties, and trade policies that would allow northern
food supplies to cover for any food gaps remaining in the
South after GRII. Likewise, they usually promote the agroindustrial
model that stresses uniformity, standardized technologies for large-scale
high-input and mechanized systems, aimed at maximizing yields of commercial
crops, to fuel a global food system.
Yet, evidence suggests that this GR approach
is unlikely to be the appropriate strategy to end hunger. Serious concerns
have been raised by economic analysts, NGOs (non-governmental organizations),
and farmers in many parts of the world, about the validity of this approach.
Earlier versions of the GR technological package have in many cases
generated soil, pest and weed problems, sometimes leading to long-term
yield decline. Bioengineering produces varieties that are not locally
adapted, and must be purchased by cash-strapped farmers. The widespread
introduction of such varieties poses environmental risks and can reduce
the genetic diversity of food crops and varieties, elevating risk and
food insecurity for farmers in many areas. Dumping of Northern food
surpluses is already a key factor depressing productivity in the South.
The GR II emphasis on capital-intensive, off-farm, chemical inputs,
is likely to both reinforce yield leveling or decline, and generate
further inequity, thus making it a less than ideal policy package for
attacking hunger.
In contrast, the agroecological approach
favored by increasing numbers of farmers, NGOs, and analysts around
the world, offers several advantages. First, it is a alternate path
to agricultural productivity or intensification that relies on local
farming knowledge and techniques adjusted to different local conditions,
management of diverse on-farm resources and inputs, and incorporation
of contemporary scientific understanding of biological principles and
resources in farming systems. Second, it offers the only practical way
to actually restore agricultural lands that have been degraded by conventional
agronomic practices. Third, it offers an nvironmentally sound, and affordable
way, for smallholders to sustainable intensify production in marginal
areas. Finally, it has the potential to reverse the anti-peasant biases
inherent in strategies that emphasize purchased inputs and machinery,
valuing instead the assets that small farmers already possess, including
local knowledge and the low opportunity costs for labor that prevail
in the regions where they live. Thus it is an approach that is likely
to decrease, rather than exacerbate, inequality, and also enhance sustainability.
Box 1: THE MEANING AND PRINCIPLES
OF AGROECOLOGY
Agroecology is a scientific discipline
that defines, classifies, and studies agricultural systems from an ecological
and socioeconomic perspective. It is also considered the scientific
foundation of sustainable agriculture as it provides ecological concepts
and principles for the analysis, design, and management of productive,
resource-conserving agricultural systems. Agroecology integrates indigenous
knowledge with modern technical knowledge to arrive at environmentally
and socially sensitive approaches to agriculture, encompassing not only
production goals, but also social equity and ecological sustainability
of the system. In contrast to the conventional agronomic approach that
focuses on the spread of packaged uniform technologies, agroecology
emphasizes vital principles such as biodiversity, recycling of nutrients,
synergy and interaction among crops, animals, soil, etc., and regeneration
and conservation of resources. The particular methods or technologies
promoted by agroecologists build upon local skills and are adapted to
local agroecological and socioeconomic conditions. The implementation
of such agroecological principles within the context of a pro-poor,
farmer-centered rural development strategy is essential for healthy,
equitable, sustainable and productive systems.
Today there are thousands of examples where
rural producers in partnership with NGOs and other organizations, have
promoted and implemented alternative, agroecological development projects
which incorporate elements of both traditional knowledge and modern
agricultural science, featuring resource-conserving yet highly productive
systems such as polycultures, agroforestry, the integration of crops
and livestock, etc.
There is enough evidence available todaydespite
the fact that researchers have paid scant attention to these systemsto
suggest that these agroecological technologies promiss to contribute
to food security at many levels. Just how productive and sustainable
they are is to some degree still an empirical question. But it is likely
that the prevalence of similar systems among smallholders is a factor
in the universally observed inverse relationship between farm size and
production, whereby smaller farms make far more productive use of the
land resources than do large farms. Yet, even medium and large scale
producers are increasingly making use of the agroecological approach,
recognizing the advantages of these principles and techniques over conventional
approaches.
Critics of such alternative production
systems point to lower crop yields and in high-input conventional systems.
Yet all too often it is precisely the emphasis on yielda measure
of the performance of a single cropthat blinds analysts to broader
measures of sustainability and to the greater per unit area productivity
obtained in complex, integrated agroecological systems that feature
many crop varieties together with animals and trees. There are also
cases where even yields of single crops are higher in agroecological
systems that have undergone the full conversion process.
Assessments of various initiatives in Africa,
Asia and Latin America show that agroecological technologies can bring
significant environmental and economic benefits to farmers and communities.
If such experiences were to be scaled up, multiplied, extrapolated and
supported in alternative policy scenarios, the gains in food security
and environmental conservation would be substantial. In this article
we summarize some cases from Latin America and Africa to explore the
potential of the agroecological approach.
Stabilizing the Hillsides of Central
America
Perhaps the major agricultural challenge
in Latin America is to design cropping systems for hillside areas, that
are both productive and reduce erosion. Several organizations have taken
on this challenge with initiatives that emphasize the stewardship of
soil resources, utilization of local resources, and inputs produced
on-farm.
Since the mid 1980s, the private voluntary
organization World Neighbors has sponsored an agricultural development
and training program in Honduras, to control erosion and restore the
fertility of degraded soils. Soil conservation practices were introducedsuch
as drainage and contour ditches, grass barriers, and rock wallsand
organic fertilization methods were emphasized, such as chicken manure
and intercropping with legumes. Program yields tripled or quadrupled
from 400 kilograms per hectare to 1,200-1,600 kilograms, depending on
the farmer. This tripling in per-hectare grain production has ensured
that the 1,200 families participating in the program have ample grain
supplies for the ensuing year. Subsequently COSECHA, a local NGO promoting
farmer-to-farmer methodologies on soil conservation and agroecology,
helped some 300 farmers experiment with terracing, cover crops and other
new techniques. Half of them have already tripled their corn and bean
yields; 35 have gone beyond staple production and are growing carrots,
lettuce and other vegetables to sell in local markets.
Throughout Central America, CIDDICO and
other NGOs have promoted the use of grain legumes to be used as green
manure, an inexpensive source of organic fertilizer to build up organic
matter. Hundreds of farmers in the northern coast of Honduras are using
velvet bean (Mucuna pruriens) with excellent results, including corn
yields of about 3,000kg/ha, more than double than national average,
erosion control, weed suppression and reduced land preparation costs.
The velvet beans produce nearly 30 t/ha of biomass per year, or about
90-100 kg of N/ha per year. Taking advantage of well established farmer
to farmer networks such as the campesino a campesino movement in Nicaragua
and elsewhere, the spread of this simple technology has occurred rapidly.
In just one year more than 1,000 peasants recovered degraded land in
the Nicaraguan San Juan watershed. Economic analyses of these projects
indicate that farmers adopting cover cropping have lowered their utilization
of chemical fertilizers (from 1,900 kg/ha to 400 kg/ha) while increasing
yields from 700 kg to 2,000 kg/ha, with production costs about 22% lower
than farmers using chemical fertilizers and monocultures.
Scientists and NGOs promoting slash/mulch
systems based on the traditional "tapado" system, used on
the Central American hillsides, have also reported increased maize yields
(about 3,000 kg/ha) and considerable reduction in labor inputs as cover
crops smother aggressive weeds, thus minimizing the need for weeding.
Another advantage is that drought resistant mulch legumes such as Dolichos
lablab provide good forage for livestock.
These kinds of agroecological approaches
are currently being used on a relatively small percentage of land, but
as their benefits are being recognized by farmers, they are spreading
quickly. Such methods have strong potential and offer important advantages
for other areas of Central America and beyond.
Agroecology in the Andean Region
In Peru, NGOs have studied pre-Columbian
technologies in search of solutions to contemporary problems of high
altitude farming. A fascinating example is the revival of an ingenious
system of raised fields that evolved on the high plains of the Peruvian
Andes about 3,000 years ago. According to archaeological evidence, these
waru-warus, platforms of soil surrounded by ditches filled with water,
were able to produce bumper crops despite floods, droughts and the killing
frosts common at altitudes of nearly 4,000 meters.
In 1984, several NGOs and state agencies
created the Projecto Interinstitucional de Rehabilitación de Waru-warus
(PIWA) to assist local farmers in reconstructing the ancient systems.
The combination of raised beds and canals has proven to have important
temperature moderation effects, extending the growing season and leading
to higher productivity on the waru-warus, compared to chemically fertilized
normal pampa soils. In the district of Huatta, reconstructed raised
fields produced impressive harvests, exhibiting a sustained potato yields
of 8-14 t/ha/yr. These figures contrast favorably with the average Puno
potato yields of 1-4 t/ha/yr. In Camjata, potato yields reached 13 t/ha/yr
and quinoa yields reached 2t/ha/yr in waru-warus.
Elsewhere in Peru, several NGOs in partnership
with local government agencies have engaged in programs to restore abandoned
ancient terraces. For example, in Cajamarca, in 1983 EDAC-CIED together
with peasant communities initiated an all-encompassing soil conservation
project. Over 10 years they planted more than 550,000 trees and reconstructed
about 850 has of terraces and 173 has of drainage and infiltration canals.
The end result is about 1,124 has of land under conservation measures
(roughly 32% of the total arable land), benefiting 1,247 families (about
52% of the total in the area). Crop yields have improved significantly.
For example, potato yields went from 5 t/ha to 8 t/ha and Oca yields
jumped from 3 to 8 t/ha. Enhanced crop production, fattening of cattle
and raising of alpaca for wool, have increased the income of families
from an average $ 108 per year in 1983 to more than $ 500 today.
In the Colca valley of southern Peru, PRAVTIR
(Programa de Acondicionamiento Territorial y Vivienda Rural) sponsors
terrace reconstruction by offering peasant communities low-interest
loans or seeds and other inputs to restore large areas (up to 30 has)
of abandoned terraces. The advantages the terraces are minimizing risk
in times of frost and/or drought, reducing soil loss, broadening cropping
options because of the microclimate and hydraulic advantages of terraces,
and improvement productivity. First year yields from new bench terraces
showed a 43-65% increases of potatoes, maize and barley, compared to
these crops grown on sloping fields. The native legume Lupinus mutabilis
is used as a rotational or associated crop on the terraces; it fixes
nitrogen, which is available to companion crops, minimizing fertilizer
needs and increasing production. As shown in Table 1, though yields
are greater in chemically fertilized and machinery prepared potato fields,
energy costs are higher and net economic benefits are not necessarily
greater than the agroecological system. Surveys indicate that farmers
prefer this alternative system as it optimizes the use of scarce resources,
labor and available capital, and is accessible to even poor producers.
These kinds of methods are being scaled up and multiplied, showing great
potential for improvements in productivity and sustainable food security
throughout the region.
Integrated Production Systems
A number of NGOs promote the integrated
use of a variety of management technologies and practices. The emphasis
is on diversified farms in which each component of the farming system
biologically reinforces the other components, for instance where wastes
from one component become inputs to another. Since 1980, CET, a Chilean
NGO, has engaged in a rural development program aimed at helping peasants
reach year-round food self-sufficiency while rebuilding the productive
capacity of their small landholdings. The approach has been to set up
several 0.5 ha model farms, which consist of a spatial and temporal
rotational sequence of forage and row crops, vegetables, forest and
fruit trees, and animals. Components are chosen according to crop or
animal nutritional contributions to subsequent rotational steps, their
adaptation to local agroclimatic conditions, local peasant consumption
patterns and, finally, market opportunities. Most vegetables are grown
in heavily composted raised beds located in the garden section, each
of which can yield up to 83 kg of fresh vegetables per month, a considerable
improvement to the 20-30 kg produced in spontaneous gardens tended around
households. The rest of the 200-square meter area surrounding the house
is used as an orchard, and for animals, (cows, hens, rabbits and langstroth
beehives).
Vegetables, cereals, legumes and forage
plants are produced in a six-year rotational system within a small area
adjacent to the garden. Relatively constant production is achieved (about
six tons per year of useful biomass from 13 different crop species)
by dividing the land into as many small fields of fairly equal productive
capacity as there are years in the rotation. The rotation is designed
to produce the maximum variety of basic crops in six plots, taking advantage
of the soil-restoring properties and biological control features of
the rotation.
Over the years, soil fertility in the original
demonstration farm has improved, and no serious pest or disease problems
have appeared. Fruit trees in the orchard and fencerows, as well as
forage crops are highly productive. Milk and egg production far exceed
that on conventional farms. A nutritional analysis of the system based
on its key components shows that for a typical family it produces a
250% surplus of protein, 80 and 550% surpluses of vitamin A and C, respectively,
and a 330% surplus of calcium. A household economic analysis indicates
that, the balance between selling surpluses and buying preferred items
provides a net income beyond consumption of US$ 790. If all of the farm
output were sold at wholesale prices, the family could generate a monthly
net income 1.5 times greater than the monthly legal minimum wage in
Chile, while dedicating only a relatively few hours per week to the
farm. The tiime freed up is used by farmers for other on-farm or off-farm
income generating activities.
In Cuba, the Asociación Cubana de Agricultura
Orgánica (ACAO), a non-governmental organization formed by scientists,
farmers and extension personnel, has played a pioneering role in promoting
alternative production modules. In 1995 ACAO helped establish three
integrated farming systems (called agroecological lighthouses)
in cooperatives (CPAs) in the province of Havana. After the first six
months, all three CPAs had incorporated agroecological innovations (i.e.
tree integration, planned crop rotation, polycultures, green manures,
etc.) to varying egrees, which, with time, have led to enhancement of
production and biodiversity, and improvement in soil quality, especially
organic matter content. Several polycultures, such as cassava-beans-maize,
cassava-tomato-maize, and sweet potato-maize were tested in the CPAs.
Productivity evaluation of these polycultures indicates 2.82, 2.17 and
1.45 times greater productivity than monocultures, respectively. The
use of Crotalaria juncea and Vigna unguiculata as green manure have
ensured a production of squash equivalent to that obtainable applying
175 kg/ha of urea. In addition, such legumes improved the physical and
chemical characteristics of the soil and effectively broke the life
cycles of insect pests such as the sweet potato weevil.
At the Cuban Instituto de Investigaciones
de Pastos, several agroecological modules with various proportions of
the farm area devoted to agriculture and animal production were established.
Monitoring of production and efficiencies of a 75% pasture/25% crop
module, reveals that total production increases over time, and that
energy and labor inputs decrease as the biological structuring of the
system begins to sponsor the productivity of the agroecosystem. Total
biomass production increased from 4.4 to 5.1 t/ha after 3 years of integrated
anagement. Energy inputs decreased, which resulted in enhanced energy
efficiency (from 4.4 to 9.5) (Table 2). Human labor demands for management
also decreased over time. Such models have been promoted extensively
through field days and farmers cross visits. Similar results have been
obtained by ICLARM researchers in Philippines, where integrated rice-based
systems with livestock, aquaculture, tree and vegetable components have
proven to be productive, efficient and profitable, given labor availability
and secure tenure.
In the African context, positive results
from agroecological approaches have also been achieved. In Senegal,
for example, the Senegal Regenerative Agriculture Center is working
to promote sustainable agriculture based on soil regeneration for small-scale
farmers who have suffered from soil degradation. The cropping system
is a millet-groundnut rotation, and legumes and intercropped with cereals.
Compost is also being used to restore soil fertility. Cows, goats, and
sheep are usually kept by each household, and their manure is collected
for the compost mixture. This project is operating in 11 villages, with
active farmer participation. Results show that farmers can obtain an
increase in millet grain of more then 400 kilograms per hectare if they
put on at least 2 tones of compost. Similar yield increases were achieved
with chemical ertilizers, but the cost-benefit ratio was less favorable.
In Tanzania, a Soil Erosion Control and
Agroforestry project was begun in 1980 in the Lushoto district. It included
planting of perennial grass along contours to alleviate soil erosion
and promote soil regeneration, as well as use of contour strips of trees,
shrubs, and creeping legumes. The combination of these integrated methods
reduced erosion by an average of 25 percent, and improved soil health.
Trees species are also valuable for fodder. Total yields per hectare
increased by 64 percent for areas with grass strips, and 87 percent
for areas with contours. Gross marginal returns were 74 percent higher
in the contour systems compared to conventional approaches. These practices
are being adopted by hundreds of people in this district, and offer
promising alternatives for many other similar farming areas.
Current experiences in Ethiopia also show
the importance of respecting and upholding agroecological principles.
In this country, as in other African nations, there have been heavy
pressures to promote GR II technologies, particularly through the widespread
imposition of uniform wheat and maize varieties, and a technology package
policy that requires farmers to buy fertilizers and other inputs. However,
local people and government and NGO officials have opposed this model,
recognizing the problems and risks it entails, and they have defended
and upheld the use of their diverse valuable local varieties of teff,
sorghum, millet, and other grains that provide food security for the
people. They also have worked on revival and "rescuing" of
local seed varieties in community-based seedbanks, and promote integration
of diverse sustainable farming practices in food security efforts.
These examples offer evidence of positive
results, and also indicate increasing adoption and spread of the methods,
as farmers realize their benefits for food security and sustained production
for market as well. In many parts of the world there is great potential
for even wider application of these agroecological approaches.
Conclusions
Throughout the developing world in
addition to the examples summarized abovethere are thousands of
experiences of sustainable agriculture implemented at the local level
by farmer organizations, NGOs, and other agencies. These experiences
demonstrate the feasibility of intensifying production, regenerating
and preserving soils, and maintaining biodiversity, based on agroecological
technologies and locally available resources. In fact, data from documented
cases show that when correctly managed, agroecological systems:
- exhibit more stable levels of total
production per unit area over time,
- produce economically favorable rates
of return, in both energetic and monetary terms,
- provide a return to labor and other
inputs sufficient to provide an acceptable livelihood to small farmers
and their families,
- ensure soil protection and conservation
and enhance agrobiodiversity.
The combination of stable and diverse production
with relatively high levels of production, internally generated and
recycled inputs and nutrients, favorable energy input/output ratios
and articulation of both subsistence and surplus for market production,
is a clear indication of what the agroecological strategy of intensification
can achieve. This approach also enables farmers to reduce dependency
on external capital-intensive inputs, to take advantage of local resources,
and to avoid the vulnerability associated with monocultural production
systems. As such, it is a more equitable and sustainable strategy than
the conventional GR approach. These experiences show direct improvements
for household food security and livelihoods. The values of such an approach
are also being recognized and shown by scientists/researchers in the
science of agroecology and its applications. Even modern commercial
agriculture enterprises who have become tired of the high costs and
constraints of conventional chemical-oriented approach are now realizing
that the state of the art in achieving success farming requires
significant changes, to better understand, respect, uphold and enhance
agroecological principles and biological limitations/capacities. As
we move toward the 21st Century, agriculture should take on a new orientation
or paradigm to achieve win-win-solutions; this orientation should be
ecologically and socially oriented, knowledge-based, and farmer-friendly.
A major question often asked is why hasnt this agroecological
approach spread more rapidly in recent decades? A major xplanation is
that powerful economic/corporate and institutional interests have backed
R&D for the conventional GR agroindustrial approach, while R&D
for agroecology and sustainable approaches has been largely ignored
or even ostracized. Only in recent years has there been growing realization
of the advantages of alternatives.
Since there is increasing evidence and
awareness about the advantages of agroecological alternatives, how can
this approach and associated technologies be multiplied and adopted
more widely and consistently, worldwide? Clearly, a technological or
ecological approach is not enough. Major changes must be made in policies,
institutions, and methods of R&D to ensure that these agroecological
alternatives are adopted, made accessible equitably and broadly, and
multiplied, so that we can realize their full benefit in terms of food
security.
The challenge is to increase the investment
and research into this strategy, and to scale-up projects that have
already proven successful, thereby generating a meaningful impact in
the income, food security and environmental integrity of the worlds
population, and especially the millions of poor farmers yet untouched
by modern agricultural technology. Existing subsidies and policy incentives
for conventional chemical approaches must be dismantled, and institutional
structures and partnerships and educational processes must change to
enable this agroecological approach to blossom. In addition, participatory,
farmer-friendly methods of technology development must be incorporated,
ensuring that women, men, elders, and marginalized poor farmers or labor
groups are included in development of alternatives. If we fail to seize
this opportunity, the existing cases will remain as "islands of
success" in a sea of deprivation, merely living testimonies of
the potential of the "path not taken" to feed the rural poor.
On the other hand, if we go forward to widely support and develop an
agroecological approach, humanity can benefit from its potential to
address the inequity, hunger and environmental degradation that so often
accompany high-input, energy intensive, corporate-style agriculture.