Ecoagriculture: 3 Goals Food production Biodiversity conservation Human livelihoods

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Ecoagriculture: 3 Goals
• Food production
• Biodiversity conservation
• Human livelihoods
Ecoagriculture’s goals are for reducing
poverty while improving water quality +
environmental sustainability
Ecosystem Services for Free!
• Goods: food, wood, medicines
• Regulating: pest control, flood
control, climate stabilization
• Supporting: pollination, soil
formation, water purification,
oxygen formation
• Cultural: aesthetic, religious,
recreational
Is this
sustainable
tree use?
Wood Harvesting – Is this
sustainable ?
The Ecoagriculture Approach
As an alternative strategy to industrial agriculture,
an ecoagriculture approach works by mimicking
natural systems to create a new ecosystem,
including perennials and native species.
By mimicking and re-creating an eco-system,
biodiversity, stability, fertility, resilience and
resistance are increased, there-by strengthening
the overall agricultural system.
Ecology is study of interactions between
• non-living components in the environment…
–
–
–
–
–
–
–
light
water
wind
nutrients in soil
heat
solar radiation
atmosphere, etc.
AND…
Living Organisms - Oh, it’s a web!
•
•
•
•
Plants – Trees, shrubs + herbs
Pollinators – birds, bees, flies, butterflies, bats!
Predators – birds, bugs, mammals, microbes
Microbes + Fungi – plant/soil symbioses, food web
• Ecology…views each locale as an integrated
whole of interdependent parts that function as
a unit. Can a farm mimic a natural habitat?
Farm
Or
Biome
caribou
tundra
Climax: a community that has reached a steady state under
a particular set of environmental conditions.
Natural Systems
A forest does not
require outside
fertilizers or
pesticides or
irrigation,
yet nutrients in
the soil, insect
ratios, water are
typically keep in
proper balance.
Oregon “old growth” climax forest
Different Wildlife use Different Stages of
Successional Environments
Ecoagriculture Strategy
• In the Agricultural Landscape:
1. Minimizing agricultural wastes and pollution
2. Conserve water, soils and native plants + animals
3. Using crops, grass, and tree combinations to mimic
ecological structures + functions of natural habitats
4. Minimize or reverse conversion of habitats
5. Protecting and expanding habitat patches
6. Develop ecological corridors and networks
Whole Farm Approach
The whole farm approach combines an integrated system that
works with nature: reducing tillage and careful application of onfarm nutrients, building soils, using renewable resources and
using less pesticides with plant and animal diversity.
Food Forests
• Food forests are not ‘natural’, but are designed
and managed ecosystems that are very rich in
biodiversity and productivity.
http://www.youtube.com/watch?v=-5ZgzwoQ-ao&feature=relmfu
Costa Rica – Shade crops
Soils – Inputs and Tillage
• Soil health and fertility is fundamental for plant
growth.
• Fertility can be built with organic inputs from the
farm. Compost breakdown stimulates more
microbial activity.
• No till methods are frequently utilized, even when
harvested, roots that remain in the ground, thus
not disturbing the soil and continuing to retain the
carbon within.
Fertilizers
Chemical additions are not
required as the system is closed
and entirely self-supportive,
additionally needed amendments
will be provided from organic byproducts of the
system. http://climatelab.org/Ecoagriculture
The Nitrogen Cycle
ADD FIG. 2.21
18
Cover Crops
Growing plants such as rye, clover or vetch after harvesting
a cash crop can provide multiple benefits, including weed
and insect control, erosion control, and improved soil
quality. Cover crops help reduce erosion worldwide.
Conservation Tillage
Many soil conservation
practices – contour tillage,
reduced tillage, and no-till,
all help to prevent soil loss
from wind and water
erosion.
Contour tillage systems
also help minimize soil
compaction, conserve
water and store carbon to
reduce carbon dioxide
emissions.
The Carbon Cycle
ADD FIG. 2.20
21
Till vs No=till Soils
Organic Agriculture
and soil quality
• The organically treated soils were physically more
stable and were found to be biologically more
active than conventional.
(DOK trials, Mäder et al., 2002)
• Under organic farming the soil organic matter captures
and retains more water in the crop root zone.
• Water capture in organic fields can also be 100% higher
than in conventional fields during torrential rains
. (Rodale Institute,
2008)
Biodiversity
• The key to an ecoagriculture system is biodiversity.
The more diverse a system is, the more stable it is,
and the more resilient it becomes.
• “Diversity provides the system with built-in
resilience to changes and cycles in climate, water,
insects and pests, grazers, and other natural
disturbances.”4
Organic Ag is good for biodiversity and
biodiversity is good for Organic Ag !
Organic farmers use more
Agro-ecological methods:
•
•
•
•
Mixed crop rotations, intercropping, …
Grasslands and green manure,
Habitats and non-farmed areas
Non-chemical pest management
Promoting functional diversity means enhancing
and benefitting from Ecological service functions:
•Pollination
•Pest and disease prevention
•Biodiversity preservation,
•Soil quality
•Resilience
•In situ conservation of genes
Animals
• Ecoagriculture uses animals to forage for weed
seeds, fertilize with their manure, and cultivate by
scratching and rummaging, which all contribute to
the health of the system. “Wastes” are also a fuel.
fuel
fertilizer
Animals
• By integrating animals into the system, instead of
separating them, the amount of food needed,
expended energy, and time used are all reduced.
Lamb
farming in
Oregon
Pest Controls
• Ecological insect and weed management avoids
solutions that can harm good insects and animals.
• It instead combines biological controls like trap
crops, hand removal of weeds + insects, birds, and
integrated pest management techniques.
Many uses of a chicken.
The Ecoagriculture approach
http://www.youtube.com/watch?v=ObLrbE6ADB8&feature=results_video&playnext=
1&list=PLA65F6C2CE6CCC4D1
Organic Agriculture promotes biodiversity
Scienific evidence…..
RESEARCH (Bengtsson et al., 2005):
• Species richness (# of species) 30% higher in organic farms (n=32)
– Birds, Plants
– Predatory insects, carabidae
• Species abundance (Commoness of species) 50% higher in organic farms
(n=117)
– Weeds, Soil organisms (earthworms)
– Predatory insects, carabidae
– Not potential pest species!
Causes for higher diversity and abundance under organic farming:
•Non use of pesticides & fertiliser
•Friendly treatment of hedgerows and non-crop habitats on organic farms
•Preservation of mixed farming and diversified land use
Hole et al., 2005 (n=76)
Agro-ecological methods could also be used in non-organic
- but in reality is not!
Economic Opportunity in Nepal
• Biodiversity provides more diverse food and
growing options, which creates flexibility in
economic opportunities for farmers.
Economic Opportunity in Oregon:
Provides an adequate and dependable farm income,
Promotes opportunity in family and farm communities
Mustard Plants are good Nitrogen fixing species
Nitrogen-fixing crops can be integrated into a system,
adding a protein source for humans and livestock, as
well as nutrients for the soil.
Perennials
• Ecoagriculture uses as many perennial
species as possible within a designed system.
• This creates the least amount of disturbance
possible to the soil.
Perennial crops
• Perennial crops have
deep roots which
prevent erosion;
• they require less
fertilizer and water;
• the roots can serve as
carbon sinks and help
offset C02 emissions.
Experimental Perennials vs Annuals
Utilizing perennials also means trees
as part of the system.
Utilizing
water
through the
use of a
swale
and crops
Wetland Habitats
• Conservation of wetlands in farming areas critical for native
bird populations.
• Modern agriculture ditches/ dries out soils, uses toxic
pesticides and removes weeds/ non-crop vegetation.
• Working with farmers to protect and enhance wetland
habitats by preserving and planting buffers benefits both
farmers and birds as birds provide a lot of “free”pest control.
Habitat
Water gurgling from a well is flooding Craig Gautreaux's rice and
crawfish fields, turning the farm into a wetland for migratory
birds whose usual Gulf of Mexico wintering grounds are
threatened by the oil spill. 7/29/2010
http://www.msnbc.msn.com/id/38475970/ns/us_news-environment/t/feds-farmers-create-habitats-
migrating-birds/#.T4c7JpkvkWA
Water
• Slow, spread, sink, shade, and store, are
imperative in ecoagriculture systems.
• When water is slowed down and spread out
and sunk, erosion is reduced and absorption
is increased.
• Shading helps reduce evaporation, thereby
making available water more efficient.6 This
is done with an increased use of trees,
mulches, and cover crops.
Ecoagriculture Goals
 Achieves the integration of natural biological
cycles and controls,
 Protects and renews soil fertility and the natural
resource base,
 Optimizes the management and use of on-farm
resources,
 Reduces the use of nonrenewable resources and
purchased production inputs,
 Minimizes adverse impacts on health, safety,
wildlife, water quality and the environment.
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