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  • From: "TradingPostPaul" <tradingpost@riseup.net>
  • To: livingontheland@lists.ibiblio.org
  • Subject: [Livingontheland] Organic matter, microbes, and plant health
  • Date: Sat, 06 Oct 2007 20:59:37 -0600


the original link for this was
http://www.fao.org/DOCREP/005/AD090E/AD090E00.HTM
it can be found at google cache
http://64.233.167.104/search?q=cache:P2yqwgRgOJYJ:www.fao.org/DOCREP/005/AD0
90E/AD090E00.HTM+http://www.fao.org/DOCREP/005/AD090E/AD090E00.HTM&hl=en&ct=
clnk&cd=1&gl=us&client=firefox-a

First here's an excerpt:
Organic matter, microbes, and plant health

"Soil organisms contribute a wide range of essential services to the
sustainable
functioning of all ecosystems. They act as the primary driving agents of:
nutrient cycling, regulating the dynamics of soil organic matter, soil
carbon
sequestration and greenhouse gas emissions; modifying soil physical
structure
and water regimes; enhancing the amount and efficiency of nutrient
acquisition
by the vegetation; and enhancing plant health. These services are not only
critical to the functioning of natural ecosystems but constitute an
important
resource for sustainable agricultural systems."

"Each type of soil organism occupies a different niche in the web of life
and
favours a different substrate and nutrient source. Most soil organisms rely
on
organic matter for food; thus a rich supply and varied source of organic
matter
will generally support a wider variety of organisms."

"Building of soil fertility is the cornerstone of organic agriculture.
Organic
practices create suitable conditions for soil biotic and abiotic resources
through: manipulation of crop rotations and strip-cropping; green manuring
and
organic fertilization (animal manure, compost, crop residues); minimum
tillage;
and avoidance of pesticides and herbicides use. Scientific research in
Europe
has demonstrated that organically-managed soils significantly increase
biological activity and total density and diversity of soil
micro-organisms.
Such biodiversity enhances nutrients recycling and soil structure."

from Organic Agriculture: The Challenge of Sustaining Food Production,
United
Nations Sub-Group Meeting on Wildlife, Biodiversity and Organic
Agriculture,
Ankara, Turkey, 15-16 April 2003
------------------------------------------------

United Nations Thematic Group
Sub-Group Meeting on Wildlife, Biodiversity and Organic Agriculture
Ankara, Turkey, 15-16 April 2003

ORGANIC AGRICULTURE:
THE CHALLENGE OF SUSTAINING FOOD PRODUCTION
WHILE ENHANCING BIODIVERSITY

Nadia El-Hage Scialabba
Secretary
Priority Area for Inter-Disciplinary Action on Organic Agriculture
Food and Agriculture Organization of the United Nations
Rome, Italy
nadia.scialabba@fao.org
Table of contents

1. INTRODUCTION

2. THE BELOW-GROUND FOOD CHAIN: SOIL BIODIVERSITY

3. THE FARMING SYSTEM FOOD CHAIN: GENETIC RESOURCES FOR FOOD AND
AGRICULTURE

4. THE ECOSYSTEM FOOD CHAIN: WILDLIFE BIODIVERSITY

5. CONCLUSIONS

APPENDIX - ORGANIC AGRICULTURE IN PROTECTED AREAS AND BUFFER ZONES - CASE
STUDIES

BIBLIOGRAPHICAL REFERENCES
1. INTRODUCTION
1.1 The problems

Environmental degradation. After half a century of high intensive input
agriculture, the yield gap between best practices and farmers' fields
remains large, agricultural lands continue to shrink and global
environmental threats are a reality, e.g. erosion of biodiversity,
desertification, climate change and other transboundary pollution.
Agriculture intensification contributes to over 20 percent of global
anthropogenic greenhouse gas emissions1. Agricultural activities affect 70
percent of all threatened bird species and 49 percent of all plant
species2. Uniform cultures have dramatically reduced the number of plants
and animals used in agriculture; currently, 1 350 breeds face extinction,
with two breeds being lost each week3. Biodiversity erosion is exacerbated
by the loss of forest cover, coastal wetlands and other wild relatives,
important for the development of biodiversity and essential for food
provision, particularly in times of crisis.

Hunger. Despite FAO's and other institutions' efforts for global food
security, the benefits of increased agricultural production often bypass
the poorest sections of the world population. Over 450 million farmers have
never had access to Green Revolution technologies such as mechanization,
irrigation, improved seeds and breeds, and synthetic fertilizers and
pesticides4. The World Food Summit stressed that hunger is a problem of
access to means of food production or means to purchase food.

Dependence. Although agriculture remains the world's single largest
employer, rural economies suffer from sharp decline in real food prices and
loss of entrepreneurial capacity. The terms of international exchange
favour importations at the expense of local production. Developing
countries, which traditionally have had a net surplus in agricultural
trade, increasingly depend on food imports. The conventional food
production model ties farmers into conditions of dependence on large
corporations to buy agricultural inputs (seeds, fertilizers, pesticides)
and to sell their produce5.
1.2 The need for a paradigm shift

Nature conservation. Protecting biodiversity at genes, species and
ecosystem levels through germplasm banks and protected areas is not
sufficient. The maintenance costs of gene banks are high, up to half of the
material collected is in need of regeneration, and "freezing" genetic
resources denies their evolution. Biodiversity is best maintained through
sustainable utilization and selection by food providers. Animals move
across boundaries and ecosystems are not immune to air and water pollution.
The 12 percent of global land areas "fenced" for nature protection are
located within or around a 40 percent land surface used by agriculture and
forestry. Food systems should be viewed as an integral part of the
ecosystem. "There is a need to manage agricultural land as part of a larger
landscape that explicitly considers ecological functioning"6.

Rural livelihoods. Rural communities need land to derive livelihoods.
National parks and protected areas have always had local culture as
components of the landscape. Ecotourism management by local residents
generates supplementary income for both management of protected areas and
rural livelihoods. Agritourism creates new opportunities for farm
employment, specialty foods and safe agro-ecosystems. There is a need to
reconnect farmers to the land by linking their productive activities with
nature conservation. A symbiotic relationship between agriculture and
natural landscape exists in the presence of ecologically managed systems.

Food self-reliance. Poor farmers and market-marginalized communities need a
food production model that relies on local natural resources and ecological
management. Where food surpluses are generated, markets should guarantee
"fair" prices. Managing local resources without having to rely on external
inputs involves substituting purchased (private) goods by (public)
knowledge of natural processes that optimize competition for nutrients and
space between species within the agro-ecosystem. By stressing
diversification and adaptive management, agricultural systems can improve
soil and water quality and the ecological services that support
agriculture, while significantly decreasing vulnerability to weather
vagaries or other factors. Where markets for ecologically-produced food
exist, farmers' return on labour are higher through consumers' willingness
to pay higher prices.
1.3 Organic agriculture and biodiversity in international agreements

Organic agriculture offers a means to address food self-reliance, rural
development and nature conservation. The common thread in this ambitious
goal is the sustainable use of biodiversity; in terms of both agriculture
contribution to biodiversity and biodiversity contribution to agriculture.

To be successful, organic agriculture needs functional groups of species
and essential ecosystem processes as its main "input" to compensate for the
restriction on (or lack of) synthetic input use. In fact, a close
relationship exists between organic agriculture and the maintenance of
biodiversity. This is expressed in the rules and regulations that govern
certified organic agriculture and by the practical experiences of organic
farmers around the world. Selected international codes and agreements
expressing the organic agriculture-biodiversity linkages and need for
further consideration are the following:

* The Vignola Declaration and Action Plan on the Relationship Between
Nature Conservation, Biodiversity and Organic Agriculture of the
International Federation for Organic Agriculture Movements, the World
Conservation Union and the World Wide Fund for Nature. This Declaration
recognizes that "organic agriculture is essential for conserving
biodiversity and Nature" and "asks environmentalists, farmers, politicians,
industry and international institutions to support and develop organic
agriculture as the most ecologically-sound agricultural system"7.
* The FAO/WHO Codex Alimentarius guidelines for Organic Food define
organic agriculture as "a holistic production management system which
promotes and enhances agro-ecosystem health, including biodiversity,
biological cycles, and soil biological activity. The primary goal of
organic agriculture is to optimize the health and productivity of
interdependent communities of soil life, plants, animals and people"8.
* The Convention on Biological Diversity (CBD) "encourages the
development of technologies and farming practices that not only increase
productivity, but also arrest degradation as well as reclaim, rehabilitate,
restore and enhance biological diversity and monitor adverse effects on
sustainable agricultural biodiversity" such as "inter alia, organic
farming"9. Furthermore, the CBD Global Strategy for Plant Conservation
includes outcome-oriented global targets for 2010 whereby using plant
diversity sustainably considers, among others, organic food as an indicator
of direct measures to reach the target of "30 percent of plant-based
products derived from sources that are sustainably managed"10.
* The Ninth Session of the Commission on Genetic Resources for Food and
Agriculture recommended that FAO further studies the "contribution of
genetic resources to the economies of member countries, the impact of
agricultural subsidies on biodiversity, and the competitiveness of organic
agriculture"11.

1.4 The role of organic agriculture in enhancing biodiversity

In organic agriculture, biodiversity is both instrument and aim. Natural
ecological balance, below and above ground, is key to its success. A
healthy soil is the base for food production and a diversity of plants and
animals on land prevents pest and disease outbreaks. Although organic
agriculture is committed to the conservation and enhancement of
biodiversity, many systems today remain limited to input substitution. To
be unlocked, the real potential of organic agriculture on biodiversity
requires a stronger shift to a systems approach, based on improved
understanding of ecosystem functions.

The presentation below describes the promising, but still scattered,
results observed in organic agriculture systems. The food chain is
described for soil systems, farming systems and the larger ecosystem. This
involves descriptions of the impact of organic management on soil
biodiversity, genetic resources for food and agriculture and wildlife
biodiversity. The latter is substantiated by a series of 19 case studies,
presented in Appendix.
2. THE BELOW-GROUND FOOD CHAIN: SOIL BIODIVERSITY
2.1 Living soils for agriculture

Soils contain enormous numbers of diverse living organisms assembled in
complex and varied communities. Soil biodiversity reflects the variability
among living organisms in the soil - ranging from the myriad of invisible
microbes, bacteria and fungi to the more familiar macro-fauna such as
earthworms and termites. Plant roots can also be considered as soil
organisms in view of their symbiotic relationships and interactions with
other soil components. These diverse organisms interact with one another
and with the various plants and animals in the ecosystem, forming a complex
web of biological activity. Environmental factors, such as temperature,
moisture and acidity, as well as anthropogenic actions, in particular,
agricultural and forestry management practices, affect to different extents
soil biological communities and their functions.

Soil organisms contribute a wide range of essential services to the
sustainable functioning of all ecosystems. They act as the primary driving
agents of: nutrient cycling, regulating the dynamics of soil organic
matter, soil carbon sequestration and greenhouse gas emissions; modifying
soil physical structure and water regimes; enhancing the amount and
efficiency of nutrient acquisition by the vegetation; and enhancing plant
health. These services are not only critical to the functioning of natural
ecosystems but constitute an important resource for sustainable
agricultural systems.
2.2 Healthy soils from agriculture

Capturing the benefits of soil biological activity for agricultural
production requires adhering to the following ecological principles:

* Supply of organic matter. Each type of soil organism occupies a
different niche in the web of life and favours a different substrate and
nutrient source. Most soil organisms rely on organic matter for food; thus
a rich supply and varied source of organic matter will generally support a
wider variety of organisms.
* Increase of plant varieties. Crops should be mixed and their
spatial-temporal distribution varied, to create a greater diversity of
niches and resources that stimulate soil biodiversity. For example, diverse
habitats support complex mixes of soil organisms, and through crop rotation
or intercropping, it is possible to encourage the presence of a wider
variety of organisms, improve nutrient cycling and natural processes of
pest and disease control.
* Protection of soil organisms' habitats. The activity of soil
biodiversity can be stimulated by improving soil living conditions, such as
aeration, temperature, moisture, and nutrient quantity and quality. In this
regard, reduced soil tillage and minimized compaction - and refraining from
chemical use - are of particular note.

Improvement in agricultural sustainability requires, alongside effective
water and crop management, the optimal use and management of soil fertility
and soil physical properties. Both rely on soil biological processes and
soil biodiversity. This calls for the widespread adoption of management
practices that enhance soil biological activity and thereby build up
long-term soil productivity and health.

Adaptation and further development of soil biodiversity management into
sustainable land management practices requires solutions that pay adequate
consideration to the synergies between the soil ecosystem and its
productive capacity and agro-ecosystem health. One practical example of
holistic agricultural management systems that promote and enhance
agro-ecosystem health, including biodiversity, biological cycles and soil
biological activity is organic agriculture.
2.3 Organic agriculture nurtures soil biodiversity

Building of soil fertility is the cornerstone of organic agriculture.
Organic practices create suitable conditions for soil biotic and abiotic
resources through: manipulation of crop rotations and strip-cropping; green
manuring and organic fertilization (animal manure, compost, crop residues);
minimum tillage; and avoidance of pesticides and herbicides use. Scientific
research in Europe has demonstrated that organically-managed soils
significantly increase biological activity and total density and diversity
of soil micro-organisms. Such biodiversity enhances nutrients recycling and
soil structure. The impact of organic management on soil biological
activity and related benefits is summarized below12:

* Abundant earthworms and arthropods. Organic management increases the
abundance and species richness of earthworms and beneficial arthropods
living above ground, and thus improves the growth conditions of crops. The
biomass of earthworms in organic systems is 30-40 percent higher than in
conventional systems, their density even 50-80 percent higher. Compared to
the mineral fertilizer system, this difference is even more pronounced.
More abundant predators help to control harmful organisms (i.e. pests). In
organic systems, the density and abundance of arthropods, as compared to
conventional systems, has up to 100 percent more carabids, 60-70 percent
more staphylinids and 70-120 percent more spiders. This difference is
explained by prey deficiency due to pesticide influence as well as by a
richer weed flora in the standing crop that is less dense than in
conventional plots. In the presence of field margins and hedges, beneficial
arthropods are further enhanced, as these habitats are essential for
over-wintering and hibernation.
* High occurrence of symbionts. Organic crops profit from root
symbioses and are better able to exploit the soil. On average, mycorrhizal
colonization of roots is highest in crops of unfertilized systems, followed
by organic systems. Conventional crops have colonization levels that are 30
percent lower. The most intense mycorrhizal root colonization is found in
grass-clover, followed by the vetch rye intercrop. Roots of winter wheat
are scarcely colonized. Even when all soils are inoculated with active
micorrhizae, colonization is enhanced in organic soil. This indicates that,
even at an inoculum in surplus, soil nutrients at elevated levels and plant
protection suppress symbiosis. This underlines the importance of
appropriate living conditions for specific organisms.
* High occurrence of micro-organisms. Earthworms work hand-in-hand with
fungi, bacteria, and numerous other micro-organisms in soil. In organically
managed soils, the activity of these organisms is higher. Micro-organisms
in organic soils not only mineralize more actively, but also contribute to
the build up of stable soil organic matter. The amount of microbial biomass
and decomposition is connected: at high microbial biomass levels, little
light fraction material remains undercomposed and vice versa. Thus,
nutrients are recycled faster and soil structure is improved.
* Microbial carbon. The total mass of micro-organisms in organic
systems is 20-40 percent higher than in the conventional system with manure
and 60-85 percent higher than in the conventional system without manure.
The ratio of microbial carbon to total soil organic carbon is higher in
organic systems as compared to conventional systems. The difference is
significant at 60 cm depth (at 80 cm depth, no difference is observed).
Organic management promotes microbial carbon and thus, soil carbon
sequestration potential.
* Enzymes. Microbes have activities with important functions in the
soil system: soil enzymes indicate these functions. The total activity of
micro-organisms can be estimated by measuring the activity of a living
cell-associated enzyme such as dehydrogenase. This enzyme plays a major
role in the respiratory pathway. Proteases in soil, where most organic N is
protein, cleave protein compounds. Phosphatases cleave organic phosphorus
compounds and thus provide a link between the plant and the stock of
organic phosphorus in the soil. Enzyme activity in organic soils is
markedly higher than in conventional soils. Microbial biomass and enzyme
activities are closely related to soil acidity and soil organic matter
content.
* Wild flora. Large organic fields (over 15 ha) feature flora as six
times more abundant than conventional fields, including endangered
varieties. In organic grassland, the average number of herb species was
found to be 25 percent more than in conventional grassland, including some
species in decline. Vegetation structure and plant communities in organic
grassland are more even and more typical for a specific site than in
conventionally managed systems. In particular, field margin strips of
organic farms and semi-natural habitats conserve weed species listed as
endangered or at risk of extinction. Animal grazing behaviour or routing
activity (e.g. pigs) was found important in enhancing plant species
composition. Weeds (often sown in strips in organic orchards to reduce the
incidence of aphids) influence the diversity and abundance of arthropods
and flowering weeds are particularly beneficial to pollinators and
parasitoids.
* High-energy efficiency. Organic agriculture follows the ecosystem
theory of a closed (or semi-closed) nutrient cycle on the farm. Organic
land management allows the development of a relatively rich weed-flora as
compared to conventional systems. Some "accompanying plants" of a crop are
considered useful in organic management. The presence of versatile flora
attracts beneficial herbivores and other organisms that improve the
nourishment of predatory arthropods. When comparing diversity and the
demand of energy for microbial maintenance, it becomes evident that diverse
populations need less energy per unit biomass. A diverse microbial
population, as present in the organic field plots, diverts a greater part
of the available carbon to microbial growth. This increases the turnover of
organic matter, with a faster mineralization and delivery of plant
nutrients. Finally, more organic matter is diverted to build up stable soil
humus.
* Erosion control: Organic soil management improves soil structure by
increasing soil activity and thus, reduces erosion risk. Organic matter has
a positive effect on the development and stability of soil structure. Silty
and loamy soils profit from organic matter by an enhanced aggregate
structure. Organic matter is adsorbed to the charged surfaces of clay
minerals. The negative charge decreases with increasing particle size. Silt
is very susceptible to erosion since it is not charged, but organic-matter
layers on the silt surface also favour aggregates with silt.

3. THE FARMING SYSTEM FOOD CHAIN: GENETIC RESOURCES FOR FOOD AND
AGRICULTURE13

There are several hundred millions of small farmers in the world who do not
have the economic means to buy high yielding seeds or the synthetic
fertilizers and pesticides necessary for conventional cultivation. Many of
these have opted for the maintenance or re-introduction of organic systems
based on traditional forms of agriculture. These promote the use of
varieties and breeds that are better adapted to local stress conditions and
do not require unavailable inputs such as, for example, veterinary drugs.

There are also farmers who have opted for organic agriculture, in part
because they wish to produce healthy and environmentally-friendly food, and
also because they are attracted by the strong demand for organic products
and the related premium prices. Market driven farmers should, as a minimum,
rotate crops as the first step towards improving agricultural biodiversity.
This is one of the methods required by organic certification bodies as well
as by financial programmes. These farmers have also opted for sowing
locally-adapted species and varieties that are more resistant to disease
and local environmental conditions because synthetic fertilizers and
pesticides cannot be relied upon.

The adoption of organic agriculture methods requires farmers to follow a
series of agronomic practices (e.g. crop rotations, crop associations,
green manure and maintenance of vegetation between rows) that make
organically managed systems biologically much more complex than
conventionally managed systems. Organic farms make use of larger numbers of
plant and animal species than conventional systems. As a result, the large
pool of genetic resources for food is maintained and other useful
organisms, such as predators, pollinators and soil micro-organisms are
increased - for the very benefit of the agricultural system.

The contribution of organic agriculture to the survival of centres of
diversity and to under-utilized species, varieties and breeds is described
below. The specific requirements of organic farmers for a productive
genetic material, in conditions of low-input and harsh environments, are
generating innovative approaches to research and development; the emergence
of participatory systems of selection and distribution of appropriate
genetic material is presented.
3.1 Maintenance of centres of diversity

The continued cultivation of crop species within their centres of diversity
plays a fundamental role in the maintenance of genetic diversity.
Preserving the integrity of centres of diversity through ecologically-sound
agriculture is an indispensable inheritance for agriculture and as such,
for food security for future generations. It is the genetic variability
that allows populations to adapt to changing environmental conditions.

In centres of diversity, the introduction of organic practices is aiding
the conservation, through cultivation, of populations with high genetic
variability. The maintenance of agricultural production in centres of
diversity requires market outlets for peasants and indigenous communities.
The new income opportunities offered by organic markets reverse the present
trend of abandoning land which has previously been economically
uncompetitive.

Examples where organic agriculture created viable means for in situ
conservation and use of areas with diverse genetic heritage include:
producing and processing cocoa in Mexico to sell Maya chocolate to
tourists, and the maintenance of naturally-pigmented cotton in Peru,
resistant to pests, diseases and drought. These organic market
opportunities provide for the economic viability of thousands of farmers
and processors and maintain genetic variability for future generations.
3.2 Revival of under-utilized species, varieties and breeds, often on the
verge of extinction

In the past, agriculture has played an important role in the maintenance of
genetic diversity. The substitution of a large quantity of species for only
a few and the adoption of high yielding and uniform varieties from a
genetic point of view, has caused a significant reduction in the genetic
inheritance of cultivated species. Many agricultural species, varieties and
breeds which have played an important role in the human diet and
traditional cultures have practically disappeared over the last century.

Organic farmers breed varieties for quality, nutrition, resistance and
yield, in reduced input growing conditions. Research has shown that these
characteristics are more likely to be found in older native cultivars. In
particular, open pollinated varieties and indigenous breeds offer diverse
and regionally adapted characteristics that are better suited to organic
agriculture.

In the last decade, the adoption of organic agriculture has indirectly
established a rescue process of species, varieties and breeds threatened by
under-use or extinction. The restoration and enhancement of under-utilized
species and varieties has been motivated by specific demands of both
consumers and farmers.
3.2.1 Consumers' demand for food with specific health characteristics

For the rescue of varieties threatened by extinction, the development of a
market is fundamental and it is here that organic agriculture plays an
important role as the price premium gives an additional value to the
product. This is especially the case now that there is a consumer' interest
in traditional, speciality and organic products.

Many consumers search for quality aspects, for either health reasons (e.g.
gluten-free crops, other medicinal properties or high fibre content) or
culinary traditions (e.g. gastronomy, taste and local diets).

Examples where organic agriculture has allowed the maintenance and
improvement of species and varieties that otherwise would suffer strong
genetic erosion or extinction include: the discovery of the nutritional
value of the gluten-free quinoa in Peru and saraceno grain in Italy;
re-introduction of local rice varieties in traditional diets and culture in
Indonesia; and economic viability of the Garfagnana spelt in Italy. These
cases provided for the survival of poor communities in marginal areas and
valorized endangered genetic resources.
3.2.2 Farmers' demand for crop varieties productive under low-input
conditions

The majority of crop varieties available on the commercial market are not
suitable for organic cultivation methods as they have been selected for
production dependent on irrigation and large quantities of synthetic
fertilizers and pesticides. Many of these are hybrids and are not
open-pollinated. In the last few years, the problem has worsened following
the arrival on the market of genetically modified varieties.

The selection objectives of organic agriculture differ from those for
conventional agriculture. It is of crucial importance to utilize the
genotype potential for an improved adaptation of varieties to the low-input
conditions prevailing in organic agriculture.

The necessity for organic farmers to find methods for obtaining quality
products with good yields and limited production costs is greater than for
other farmers. Besides the fact that organic farmers cannot apply synthetic
inputs, their use of organic fertilizers, natural pesticides and other
permitted substances is uneconomical in the long-term. Permitted external
inputs as such are relied upon mainly during the conversion period to
organic agriculture or under exceptional circumstances. The comparative
advantage of certain varieties to withstand local natural stress,
especially in marginal areas, leads organic farmers to adopt biodiversity
management as their main productive strategy.

Empirical organic breeding systems have been based on the selection of
individuals better adapted to the local environment and that are more
resistant to pests and diseases. Many of these systems have demonstrated
interesting results in restoring and improving local varieties.

Examples of restoration of varieties and breeds include: the rescue, in
Germany, of an old variety of wheat with a vegetative cycle that allows the
absorbency of nitrogen available in sandy soils; in Cuba, the success of
local pumpkin varieties is used as the basis for the refinement of
methodologies for the selection of varieties for low-input situations.
3.2.3 Farmers' demand for breeds adapted to environmental conditions and
diseases

Animal breeding for high performance and selecting for early maturity have
led to increased susceptibility to diseases, joint inflammation and
mastitis as well as circulatory, metabolic and fertility problems of
livestock. Loss of breeds is exacerbated by the narrowing genetic base of
modern breeds and hybrid lines. The trend towards inbreeding increases the
degree of genetic uniformity in the animals and hence, susceptibility to
infection, parasites or epidemics.

A significant proportion of local breeds remains in the care of pastoral
people and traditional livestock owners in developing countries (e.g. pigs
in China, cows in India and poultry in Asia and Latin America). Local
breeds are suitable for free ranging and robust, thus viable in marginal
areas. While the yield may be less in the short-term, animals are more
resilient and able to survive in the long-run.

Examples where organic agriculture restored, through utilization, genetic
resources resilient to local natural stress include: productive rearing, in
Italy, of authochthonous races of the Maremmana cattle, on the verge of
extinction, due to its suitability to grow in marshy environments, and the
re-establishment of native poultry in South Africa, due to their resistance
to Newcastle disease.
3.3 Alternative systems of selection and distribution of organic genetic
resources

Historically, farmers have managed many varieties and breeds according to
agronomic and culinary properties. Considering the need for a wide gene
pool to improve and multiply genetic resources for food and agriculture,
breeding requires access to seeds and breeds from the formal and informal
sectors. Open pollinated varieties, which represent an important gene pool
for resource-poor farmers living in marginalized and stress-prone areas,
are rapidly vanishing. They are replaced by very few hybrid varieties which
require inputs not available to poor farmers and which entail dependence on
large seed companies.

Limitations and threats associated with crops have stimulated many organic
farmers, especially in the horticulture sector, to produce their own seeds.
In order to do this, they have often had to rescue local varieties and
develop their own system of selection and distribution. In many cases, the
systems include the exchange of seeds between farmers as a fundamental
instrument (e.g. organic seed fairs).

Organic systems encourage the preservation and expansion of older, locally
bred and indigenous varieties and breeds. Farmers who save their own seeds
can gradually increase crop resistance to pests and diseases by breeding
for "horizontal resistance". Horizontal resistance is the ability of a crop
to resist many or all strains of a particular pest (which differs from
breeding for "vertical resistance" to have a gene to resist one specific
strain of a disease). By exposing a population of plants to a certain
disease or pest (or to several pests at one time), then selecting a group
of the most resistant plants and interbreeding them for several
generations, a given population becomes more resistant than the original
population. Horizontally resistant cultivars are well adapted to the
environment in which they were bred, but may be less suitable for other
growing conditions.

Benefits derived from new varieties bred by farmers require a legal system
of common ownership that allows equitable access and benefit sharing. The
biodynamic network of farmers and breeders in Germany provides an example
of how such a system could be organized: trials, selection and evaluation
of genotypes adapted to low-input conditions is made by farmers and common
ownership of new varieties is shared by the community.

Organic agriculture is providing an important contribution to the in situ
conservation, restoration and maintenance of agricultural biodiversity. The
spontaneous establishment of participatory systems of research and
development is shaping a simple and practical system of equitable sharing
of benefits derived from genetic resources for food and agriculture. The
growth pattern shown by the conversion to organic agriculture throughout
the world suggests that this contribution is likely to increase still
further.
4. THE ECOSYSTEM FOOD CHAIN: WILDLIFE BIODIVERSITY
4.1 The inter-dependency between wildlife and agriculture

According to the IUCN Red List of 2000, approximately 70 percent of all
endangered species of birds and 49 percent of all plant species are spoiled
by agricultural activities and approximately 25 percent of the world's wild
animals and plants is running the risk of extinction by the middle of this
century.

Agricultural productivity depends upon the maintenance of ecological
balances and the natural properties of plants and animals. The fundamental
role of maintaining (or restoring) biodiversity is demonstrated through
ecological services such as pollination of crops, predation for biological
control of pests, micro-organisms' maintenance of soil fertility and other
services vital to the food web.

On the other hand, agriculture has the same important role in wildlife
conservation, provided that it avoids the use of substances (e.g.
pesticides) that could have a harmful effect on natural species and that it
maintains food and shelter through a diversified landscape and permanent
vegetation (e.g. trees, hedges and fields margins). Finally, a type of land
use that provides suitable biological corridors is essential for wildlife
conservation.

Nature conservation has traditionally consisted of geographically targeted
efforts. While this approach has resulted in a number of successes for rare
species or key locations, worrying declines of protected species have
occurred. A healthy environment is a prime objective for the conservation
of vital terrestrial ecosystems and the wildlife in it. Natural faunal and
floral species have strong connections with agriculture, whatever their
habitats are, especially as agricultural fields occupy much of the earth's
land surface.

Protected areas simply cannot be viewed in isolation from the communities
within and near them. Almost everywhere, rural dwellers claim historical
rights on protected areas which governments have, at a point in time,
declared "protected" for national interest. People inhabiting within or in
the neighbourhood of protected areas depend directly on their resources for
a living. In India, for example, at least three million people live in
protected areas and many other millions live in their proximity. In Latin
America, about 86 percent of national parks are inhabited by indigenous
people and migrants14. This very dependency on protected areas and its
diversity of life forms imposes ecological farming policies. If nature is
to be protected successfully, protected area dwellers should be given
agricultural choices which are not environmentally destructive and
economically rewarding.

Considering that the relationship between wild biodiversity and agriculture
is reciprocal, the protection of wildlife, biodiversity and natural areas
must include a correct management of agricultural systems.
4.2 Organic agriculture and nature conservation

There is no doubt that farmers are the most important managers of natural
resources. Several studies indicate that organic agriculture safeguards
non-agricultural biodiversity and offers a viable alternative in protected
area categories where human activities are allowed. Most importantly, the
huge land surface surrounding protected areas requires an agro-ecosystem
management that preserves the safety and integrity of the landscape. If
farm land bordering and connecting protected areas employ organic methods,
there is no reason to fear the loss of wildlife or contamination of air,
water and soil. These buffer zones are critical to the success of
conservation in the protected areas.

Organic agriculture enhances people's ability to live in harmony with
nature and to derive economic benefit from their land. Considering that
most protected areas traditionally belonged to local villagers, organic
agriculture allows local people to maintain some control over their land,
protect land and biodiversity through their farming practices, reap its
benefits for themselves and, at the same time, conserve and improve the
natural environment.

The direct impact that organic agriculture has on ecosystems can be seen on
different scales: on-farm, farm margins, and overall ecosystem. While
on-farm biodiversity has been discussed in the sections above, the
following sections will consider the interactions of organic agriculture
with the wider landscape, namely protected areas and buffer zones.
4.3 Organic agriculture in protected areas and buffer zones15

Certain protected area categories allow sustainable land-use activities
such as organic agriculture, management of non-timber forest products,
fishing, subsistence hunting and ecotourism. Organic farming within
protected areas is a growing practice that can "help to define and control
sustainable land uses in those protected areas containing significant human
populations16".

There are some 350 Biosphere Reserves in 85 countries to protect
ecosystems. The area surrounding a biosphere reserve, named buffer zone17,
plays a critical role because activities carried out here strongly
influence the core of the protected area itself. Often buffer zones are
areas dedicated to agricultural practices. Conversion to organic systems
can reduce the detrimental effects of conventional farming, and can provide
sustainable systems, suitable for the management restrictions governing
buffer zones, and consequently to natural ecosystem conservation.

The protection of the natural heritage must consider the impact, be it
positive or negative, that human activities have on it. The characteristics
of agriculture make it one of the main activities to be practised in
protected areas and buffer zones. Organic agriculture offers a suitable
alternative in ecosystems where geographic and morphological conditions are
favourable to human activities, such as wetlands and lowland forests. Also,
the ecological services offered by organic agriculture in biological
corridors are of extreme importance.

Although outside the scope of this paper, the opportunity to develop
(on-farm) agritourism or (around farm) ecotourism for city dwellers, who
appreciate a healthy and diversified rural landscape, creates new income
opportunities for organic farmers.
4.3.1 Organic agriculture and wetlands conservation

Wetlands are defined in the Ramsar Convention as "areas where water is the
primary factor controlling the environment and the associated plant and
animal life. They occur where the water table is at or near the surface of
the land, or where the land is covered by shallow water"18. Wetlands are
present in every country, from the tundra to the tropics. Their ecological
importance derives from their capacity to host high concentrations of
birds, mammals, reptiles, amphibians, fish and invertebrate species. In
fact, wetlands are boundary areas that combine the components of marine,
fluvial and terrestrial ecosystems.

In addition, many functions of wetlands derive from the interactions of
different properties of soils, water, plants and animals. Some of these
functions include, for example, water purification, water storage, flood
mitigation, recharge and discharge of underground aquifers (by the movement
of water), and stabilization of local climatic conditions.

Natural wetlands are among the most threatened ecosystems in the world.
Their high productivity and the morphologic characteristics make wetlands
excellent areas for many human activities, especially agriculture. Often
the damage caused by land reclamation for agriculture or unsustainable
practices leads to the disappearance of wetland areas and corresponding
biodiversity. Suitable management is therefore a critical priority to save
these fragile ecosystems.

Organic agriculture can help wetland conservation, by providing suitable
habitats for wildlife species, reducing water pollution and, at the same
time, offering a valid economic alternative to the exploitation of natural
resources.

Examples where the avoidance of synthetic inputs and cropping strategies
employed by organic farmers in wetlands offered breeding and feeding
habitats for endangered wildlife include: return of cranes and storks in
the cereal production in Muravia Park, Russia and of egret and heron in
rice production in the El Ebro Delta, Spain. Organic beef production in the
Pantanal Region, Brazil, created natural grasslands vital to wild mammal
herbivores in an area considered the world's biggest ecological sanctuary
(including many endangered species such as the Pantanal marsh deer) and
which previously suffered from deforestation of savannah and implementation
of artificial pastures for beef.
4.3.2 Organic agriculture in protected forest areas

Human activities such as modern agriculture and grazing can be a serious
threat to forest ecosystems and hence, for a large percentage of the
world's flora and fauna. In fact, the practice of clearing the tree cover
often interrupts the continuity of canopy, an essential characteristic for
genetic and specific biodiversity flow. In many cases, the same
agricultural fields are also a barrier to wildlife movement, and pollution
from agrochemical abuse may have negative impacts on forests.

Organic management in forest areas has the potential to reduce the loss of
biodiversity caused by these agricultural activities. The organic systems
utilized in forest areas are shade and sun cultivations. In the first case,
the plants are grown under a canopy that consists of original forest trees
or selected plants. In the latter, there is no forest cover on the
agricultural field.

Although yields of full sun production are often higher than for shade
cultivations, the latter provide timber, fuelwood and other fruits, and
have a lower soil erosion rate. Shade plantations have been shown to be
highly beneficial to biodiversity conservation in tropical forest
ecosystems, including millions of migratory birds and other animals and
plants.

For example, the Smithsonian Migratory Bird Centre's research has
demonstrated that bird species are almost twice as large in shade coffee as
in sun coffee19. Shade coffee cultivation therefore offers important
conservation opportunities as the structural profile of shade coffee farms
is similar to natural forest, providing habitat suitable for resident birds
and migrants. As a result many scientists and conservationists believe that
shade coffee plantations are ideal zones for migratory birds.

The Northwest Shade Coffee Campaign has obtained statistical data on shade
coffee as compared to sun coffee and has shown how shade cultivations are
preferred by bird species (approximately 150 compared with 20-50 species),
mid-size mammals (24 species compared with almost none) and several species
of ants, beetles, amphibians, epiphytes and others. Smithsonian Migratory
Bird Centre's studies indicates that at least 180 species of birds live in
Mexican shade coffee and cocoa fields (much more than on other agricultural
lands), and that 90 percent fewer bird species live in Colombian sun coffee
plantations than in shade coffee20.

Researchers highlighted the capacity of the canopy cover to support
secondary structures (e.g. epiphytes, parasites, mosses and lichens), which
in turn support arthropods, amphibians and other living beings. Another
relevant fact is that shade coffee hosts a large density and diversity of
predators and parasitoids involved in the control of insect pests. Shade
coffee offers an optimal habitat also for other tropical forest species,
such as beetles, ants, wasps and spiders, and supports a high diversity of
many vertebrate groups (small mammals as opossums, squirrels, mice and
bats)21. Finally, areas of high ecological value located around coffee
farms are protected.

Examples of the co-existence of shade organic cultivations and richness of
biodiversity in forest ecosystems include: shade coffee in the buffer zones
of El Trionfo Biosphere Reserve, Mexico; shade cacao in the tropical forest
of Montes Azules Biosphere Reserve, Mexico; and yerba mate in the
threatened Atlantic rainforest of the Guayaki Biological Reserve, Paraguay.

Examples of conversion to organic agriculture to reduce pressure on
endangered forests include: land exchange between Del Oro orange production
and Guanacaste Conservation Area in Costa Rica to restore rare native
forests; organic bananas to protect the threatened Guaraquecaba Atlantic
forest and its extraordinary biodiversity in Brazil; and the
re-introduction of native species through agroforestry in Ampay Forest
Sanctuary in Peru. In all these cases, local communities' income was raised
while providing benefits to the environment.
4.3.3 Organic agriculture in biological corridors

Corridor zones link protected areas with one another and either remains
under wild cover, or are managed to ensure that human land use is
compatible with the maintenance of a high degree of biological
connectivity. These areas have a fundamental ecosystem function forming
part of a large-scale ecological web.

To be effective, biological corridors must offer suitable habitats to
wildlife, thus the maintenance of a healthy environment is necessary. Areas
joining parks or reserves are equally important for biodiversity
conservation as they ensure ecosystem connectivity. These "linkage" areas
often host agricultural systems but if they are managed in an unsustainable
manner, the vitality of these corridors decreases or is totally hindered.

Careful organic management in agricultural land between (and sometimes
inside) the protected areas has permitted the creation of important
biological corridors and allowed the protection and increase of biological
diversity. Through on-farm structured vegetation and canopy tree diversity,
organic agriculture has demonstrated its capacity to provide livelihoods to
farmers while providing easier movement of animals between managed forests
and protected areas.

One of the largest, most unique conservation efforts presently underway in
the world is the Meso-American Biological Corridor that runs across seven
countries, covering an area of 770 000 km2, from Panama to Mexico. Examples
of organic cultivations include: shade coffee in the buffer zone between El
Imposible and Los Volcanes National Parks in El Salvador where hundreds of
endemic and threatened birds, mammals, reptiles and trees strive; and shade
cacao and bananas in the Talamanca-Caribbean Biological Corridor and its
buffer zones, Costa Rica, where most of the fauna is endemic. Organic
systems offer habitats similar to intact forests, providing suitable refuge
for migratory and resident birds and foraging for many forest mammals,
including species at risk.

Organic land management and bird conservation programmes exist in several
northern countries. Examples include: organic crop and livestock production
in Brandenburg, Germany where the higher presence of skylarks has been
observed; and organic farming inside a wildlife corridor that connects
Adirondak National Park and Lake Champlain in the State of New York, USA.
5. CONCLUSIONS

Farmers and forest dwellers are the main users and managers of the earth's
natural resources. Land management, including its domesticated and wild
biodiversity, relies on agricultural activities that build
self-regenerating food systems. The sustainable management of farms and the
appropriate agricultural and environmental policies have a great
responsibility with regards to the linkages between agriculture and nature
conservation.

Meeting food needs while protecting the natural heritage is a challenge
shared by all countries of the planet. Organic agriculture can meet this
challenge head-on by:

* promoting market-based incentives that compensate farmers for their
stewardship efforts, thus maintaining their economic viability;
* replacing polluting agricultural practices with approaches that can
reverse the dramatic trends in biodiversity loss;
* thriving on community participation in land conservation.

Organic agriculture has demonstrated its ability to not only produce
commodities but also to "produce" biodiversity at all levels. However, it
is logical to assume that in wild areas, organic agriculture is a
disturbance to natural habitats by the very fact of human intervention. In
any case, it offers an important step towards a solution to many of the
threats that conventional agriculture has on biodiversity. Organic
agriculture should be considered simply as the most appropriate starting
point from which additional conservation needs, where they exist, can be
built. Its widespread expansion would be a cost-efficient policy option for
biodiversity.

Research and development is necessary to better understand the complex
ecological processes as well as the management capacity of farmers. If
organic agriculture is given the consideration it merits, it has the
potential to transform agriculture as the main tool for nature
conservation. Reconciling biodiversity conservation and food production
depends upon a societal commitment to supporting organic agriculture.



1 OECD, 2001.
2 IUCN, 2000.
3 FAO, 2000.
4 FAO, 2002.
5 FAO, 2002b.
6 Scherr, 2003.
7 IFOAM, IUCN, WWF, 1999.
8 FAO/WHO, 1999.
9 Convention on Biological Diversity, 1996.
10 Convention on Biological Diversity, 2000.
11 Commission on Genetic Resources for Food and Agriculture, 2002.
12 FiBL, 2000.
13 For further details of examples mentioned under this section, see N.
El-Hage Scialabba , C. Grandi and C. Henatsch, 2003.
14 McNeely J.A., 1999.
15 The case studies mentioned under this section are in Appendix.
16 Stolton S. and Dudley N. in WWF website.
17 Buffer zone is defined as "an area on the edge of a protected area that
has land use controls and allows only activities compatible with protection
of the core area, such as research, environmental education, recreation,
and tourism" (FishBase Glossary).
18 Ramsar Convention on Wetlands website.
19 Smithsonian, 1994.
20 Greenberg R., 1994; Smithsonian Migratory Bird Center, 1994 in Rice R.
and Ward J., 1996.
21 Perfecto et al., 1996; Perfecto I. and Snelling R., 1996, Estrada A. et
al., 1994, in Rice R. and Ward J., 1996.







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