Agriculture Reference
In-Depth Information
components of systems. It also recognizes that ecosystem services upon
which society depends flow from managed landscapes, and that evaluat-
ing an ecosystem on the basis of a single indicator cannot capture the
ecosystem's full range of benefits.
Miguel Altieri proposed three chief characteristics of agroecology: a
systems framework of analysis, a focus on both biophysical and socio-
economic constraints on production, and use of agroecosystem or region
as a unit of analysis.
34
More recently, Altieri has described agroecology
as optimizing agroecosystem processes, which correspond rather well
with the practices promoted by California's agroecological partnerships
(see table 1.1).
35
The term “agroecology” was created in Mexico by ecol-
ogists, agronomists, and ethno-botanists as an agricultural development
framework in opposition to the Green Revolution.
36
In its original form,
agroecology helped peasants improve their indigenous farming practices
as an alternative to high input, chemical-intensive agriculture.
Agroecology in advanced industrialized countries necessarily draws
more from ecological sciences than from traditional, indigenous ethno-
botanical knowledge more typical of the developing world. Over the past
50 years, industrialized US agriculture has discarded the ecological
wisdom inherent in farming systems that integrate animals and crops.
Here growers must learn to manage nutrients in ecologically informed
ways, and devise alternatives to essentially ecologically irrational tech-
nologies (e.g., organophosphates). An agroecological or farming systems
perspective identifies nutrient loss and non-target pesticide impacts as
consequences of leaky, poorly assembled, and brittle systems.
37
Coping
with these as symptoms is essentially a holding action, and authentic
solutions require rethinking the design and management of agroecosys-
tems based on principles derived from the study of natural ecosystems.
Agroecology proposes developing strategies and practices informed by
the science of ecology, adding biological diversity to farming systems,
and managing their interactions for synergistic benefits for the farmer
and society. Ideally, nutrients would no longer leak from the system
because they would be circulated back to other organisms, such as
manures serving as plant fertilizers. “Pest” populations would not
explode to economically damaging levels because the niches they exploit
would be occupied by a range of other organisms, or their populations
would be regulated by predators or parasites. For example, instead
