Agroecology and SustainableDevelopment

Dr. Emilio Pérez Castellón

Visiting Scholar UC Berkeley

Mentor: Dr. Miguel A. Altieri

Norman E. Bourlag International Aghricultural Science andTechnology Fellows Program for Central America

Concepts

• Agroecology

– Application of ecological concepts andprinciples to the design and management ofsustainable agroecosystems, provides a framework to asess the complexity ofagroecosystems (Altieri, 1995)

Concepts

• Sustainable development

– Sustainable development is development thatmeets the needs of the present withoutcomprimising the ability of future generationsto meet their own needs (Bruntland, 1992)

Agroecology purpose

• What is the reason to bother talking aboutagroecolgy?– Is FOOD being produced in sufficient

amount?– Is this food being produced in an

environmentally sound way?– Are food and natural resources key issues in

human development?

Human and environmentalproblems

• Population growth• Wasteful of resources• Destruction and degradation of wildlife

habitats• Extinction of plants and animals• Poverty• Pollution• Problems are interconnected and are

growing exponentially

Human population

• World population, more than doubled in only 44 years

• 2.5 billion in 1950• 5.5 billion in 1996• Estimations:

– 8.2 billion in 2025– 10-11 billion in 2050– 14 billion in 2100

Environment and food production

• Human activities have disturbed 73% ofthe earth´s land area

• Producing food by conventional meansses more soil, water, plant, animal, andenergy resources and causes more pollution and environmental damage thanany other human activity

• Only 15 plant and 8 animal species supply90% of our food

Environment and food production

• Genetically Modified Organism (GMO)– 1999 enough food to feed 8 billion– Food available: 4.3 pounds/person/day

(Grains, beans, nuts, meat, milk, eggs, fruitsand vegetables)– US: 7 out of 10 pounds of grain are fed to

animals– Developing countries devote thousands of ha

to feed cattle in USA and Europe

Environment and food production

• Genetically Modified Organism (GMO)– Haiti:

• 1986 imported 7,000 tons of rice• 1996 imported 196,000 tons• Effects? Land and economical losses,

unemployement, poverty, hunger, malnutrition, etc.– Paradigm one gene-one constraint (pest,

drought, soil)– No scientist can ascertain that GMO foods are

risk free

Environment and food production

• Genetically Modified Organism (GMO)– Advocation for UDC high-capital and input-

intensive approach– Instead:

• Agroecological model, biodiversity, recycling ofnutrients, synergy among crops, animal, soils, andother biological components, regeneration andconservation of resources

– 22 million ha of land under organicmanagement

Agroecology purpose

– Excess pesticides

– Excess fertilizers

– Low SOM content

– Low SB activity

– Moisture imbalances

– Monoculture

– Low functional biodiversity

– Genetic uniformity

– Nutrient deficiencies

•Causes of agroecosystems dysfunction

The ecological consequences of monoculture with special reference to pest problems and the agrochemical treadmill.

Monoculture

Natural vegetation displacement

Intensive use of fertilizers

Intensive use of pesticides

Massive suply of

host plants

Destruction of beneficial

habitat f

Herbicides Insecticides

Nutricional imbalance in

crops Resistance to insecticides

Elimination of natural enemies

Host plant switch

Reduction in biodiversity

Higher vulnerability to

pests

Recruitment of herbivores

Disruption of natural control

In situ completion of life cycles

Elimination of trap crops and insectary plants

harboring natural enemies

Pest resurgence

Secondary pests More severe pest problems

Treadmill Effect

Lower effectiveness of insecticides Higher use of insecticides Higher costs of production Yield decline in the long term

Agroecology purpose

• What is agroecolgy´s main goal?

– To provide the knowledge and methodologynecessary for developing an agriculture that ison the one hand environmentally sound andon the other hand highly productive, sociallyequitable and economically viable.

Principles of Agroecology

• Enhance recycling of biomass andoptimizing nutrient availability andbalancing nutrient flow.

• Securing favorable soil conditions for plantgrowth, particularly by managing organicmatter and enhancing soil biotic activity.

Principles of Agroecology• Minimizing lossess due to flows of solar

radiation, air and water by way of microclimatemanagement, water harvesting and soilmanagement through increased soil cover.

• Species and genetic diversification of theagroecosystem in time and space.

• Enhance beneficial biological interactions andsynergisms among agrobiodiversity componentsthus resulting in the promotion of key ecologicalprocessess and services.

The components, functions, and enhancement strategies of biodiversity in agroecosystems. COMPONENTS FUNCTIONS ENHANCEMENT

Pollinators Predators

and parasites

Herbivores Noncrop

vegetation Earthworms Soil mesofauna

Soil microfauna

Intercropping Agroforestry Rotations Cover crops Nontillage Composting Green manure OMA Windbreaks

Pollination

Genetic introgression

Population regulation

Biological

control

Biomasa consumption

Nutrient cycling

Competition Allelopathy Soruces of

natural enemies Crop wild relatives

Soil structure

Nutrient cycling

Decomposition

Predation

Nutrient cycling

Nutrient cycling

Disease

suppression

AGROECOSYSTEM BIODIVERSITY

A classification of dominant agricultural agroecosystems on a gradient of diversity and vulnerability to pest outbreak.

Decreasing level of biodiversity

Increasing possibility for pest buildup

Perennial crop based

Tropical home gardens Agroforestry

Mixed cropping

Annual crop based

Rotations Monoculture

Multilayered

Monolayered

Cover crops

Monocultures

Relay cropping

Legume based

Non legume based

Plantations Orchards

Cover crops

Monocultures

Intercropping

Vegetables Strip

cropping

Row cropping

Grains

Agroecology purpose

• Land Equivalent Ratio, LER

– The relative land area required for sole cropsto produce the same yields as intercropping.

– LER = YA + YB / SA + SB

– YA and YB individual yields from crops in intercropping

– SA and SB same species yields as sole crops

Family

Crops&

IPM

AFS

MinorLivestock

Soils&

Water

Inputs Outputs

MoneyMaterials

Knowledge

ProductsDiversification

Tecnology

Farming System Model

Socioeconomic Analysis

Medicinal Plants Trials in five farms, Pacora

Rosa Jamaica

Noni

Medicinal Plants Trials in five farms, Pacora

Shampoo & candels workshop

Lombriculture

Milking goats

Fodder bank trial

Leucaena

Marango Quelite

Minor livestock shelters

Solar pannels

Centrifugal waterpump

Future Collaboration• Contacts• Organization• Information

• Funds needed for:

• Training• Research• Publications• ICT

Thank you for your kind attention!!!!!

Comments, questions?