Merging the best of the Green and Blue Revolutions : Integrating

aquaculture with agriculture

Kevin Fitzsimmons University of Arizona, Professor

World Aquaculture Society, Past-PresidentAmerican Tilapia Association, Sec./Tres.

Global food crisis

Rapidly increasing population Diversion of foods to fuels Increased costs for water, fertilizer, fuel Multiple demands for farmland (urban

sprawl, industrial and mining, solar and wind generation, wildlife conservation, watershed protection, etc.)

Need for second generation biofuels

Need new model for food production

Green Revolution – huge increase in food production, but heavy reliance on irrigation, fuel and fertilizer

Blue Revolution – almost 50% of seafood is farm raised, but many environmental impacts (effluents causing eutrophication, algae blooms, cage conflicts with other users in oceans, bays and lakes)

Green RevolutionBenefits

Large increases in yield Improved varieties

Needs Increased demand for

trained specialists Sophisticated farmers

Costs

Large demand for fertilizer

Increases in irrigation (area, amount, frequency)

Less “organic” More pollution

Needs More education & training

Blue RevolutionBenefits

Large increases in seafood yield

Domesticated stocks

Needs Increased demand for

trained specialists Sophisticated farmers

Costs

Demand for feeds with fishmeal

Demands for clean water (volume and surface area)

Diseases and parasites Effluent pollution, algae

Needs

On-land farms More education & training

Historical perspective

Traditional farming around the world integrated livestock and crops

East and South Asian farmers have long tradition of integrating agriculture and aquaculture

Asian sustainable farming systems support huge populations

Fish – vegetable – rice (complex carb) diet is suggested by most nutrition experts

Historical perspective

Modern agriculture cannot follow Asian model of small-farm integrated systems (gardening)

We need an industrial version merging aqua- and agri- cultures

Taking the best of the Green and Blue Revolutions

Green Revolutions weaknesses are Blue Revolutions needs and vice-versa

1. Fertilizer demand

2. Increase in irrigation

3. Chemical fertilizers pollute groundwater

4. Industrial crops with by-products

1. Aquaculture effluent rich in N and P

2. Fish grow well in irrigation water

3. Fish wastes are slow release, organic

4. Fish feeds need alternatives for fish meal and oil

Models

Arid lands Tropical lands Tropical coastal Temperate lands Marine

Arid Integrated Systems

Tilapia Grapes, wheat, olives, barley, sorghum, cotton, melons, peppers

Data report – Tilapia effluents irrigating cotton

Water pH reduced from 8.3 to 8.0Added 19.7 kg/ha total N during one crop.

0

5

10

15

20

25

Tot

al N

app

lied

wit

h w

ater

(kg

/ha)

WellPond

Olives with aquaculture effluentOlives with well water

Olive Tree Height Over Time

1

1.11.2

1.3

1.4

1.51.6

1.7

1.8

Mar-0

2Ap

r-02

May-0

2Jun

-02Jul

-02Au

g-02

Sep-0

2Oc

t-02

Nov-0

2De

c-02

Jan-03

Feb-0

3Ma

r-03

Apr-0

3Ma

y-03

Jun-03

Jul-03

Aug-0

3Se

p-03

Oct-0

3No

v-03

Dec-0

3Jan

-04Fe

b-04

Heigh

t (m)

Effluent Fertilizer Well Water

Data report -Olives irrigated with effluent

Tropical Inland Integrated Systems Tilapia oil palm, rice, sugar cane

Coastal Integrated Systems

Shrimp / fish Halophytes and seaweeds

Fish-shrimp-halophytes Eritrea

Shrimp and Salicornia (halophyte)

Temperate Integrated Systems Carp vegetables Catfish soybeans, corn Trout alfalfa, vegetables Aquaponics

Marine Integrated Systems

Salmon kelps, nori, mussels Shrimp seaweeds and oysters Fish seaweeds, bivalves

Shrimp/fish and edible seaweeds

Data report - Daily growth rates of Gracilaria with shrimp effluent over 4 weeks

0123456789

10

In effluentchannel

Transferredto ocean

Chemicalfertilizer

Not fertilzed

Why Tilapia ?Second most important farmed fish after the

carpsMost widely grown of any farmed fish In 2007 moved up to fifth most popular

seafood in the US

What’s needed next?

Large scale investment Best technologies of ag and aqua Economies of scale Governmental consideration Trained production staff and semi-skilled

farming staff

Multiple use of Water Gila Farms, AZ