AGROECOSYSTEM ANALYSIS GORDON R CONWAY ICCET [PDF]

AGROECOSYSTEM ANALYSIS

GORDON R CONWAY

ICCET SERIES E No 1 1983

Centre for Environmental Technology and

Department of Pure and Applied Biology,

Imperial College of Science and Technology,

London, SW7 ILU, United Kingdom

Imperial College Centre for Environmental Technology

Series E "The Dynamics of Environmental Systems"

Rep irts in this serie are working papers and are intended for discussion purposes

only. This report does not contribute a formal publication and should not be

quoted without permission of the author.

This report has been submitted for publication in

Agricultural Ecosystems Environment

Imperial

College Centre for Environmental Technology

Imperial College of Science and Technology

48 Prince's Gardens

London SW7 ILU

83-E-1

-,I­

CONTENTS

PAGE

ABSTRACT

3

INTRODUCTION

4

THE CASE FOR A HOLISTIC APPROACH

4

THE CONCEPTUAL BASIS

10

THE PROCEDURE OF ANALYSIS

18

OBJECTIVES AND DEFINITIONS

OBJECTIVES

23

SYSTEM DEFINITION

23

26

PATTERN ANALYSIS SPACE

26

TIME

27

FLOW

32

DECISIONS

36

SYSTEM PROPERTIES

36

KEY QUESTIONS

39

RESEARCH DESIGN AND IMPLEMENTATION

42

DISCUSSION

43

ACKNOWLEDGEMENTS

46

REFERENCES

47

2

recent years there has been a growing demand for a

In

research

and holisric content to agricultural

multidisciplinary

more

and

development and for the formulation of methods by which this

can

be acheived.

in common with

development are two responses to this demand but, other

rural

Farming systems research and integrated

multidisciplinary

approaches,

they face the

problem

of

trying to encompass a breadth of expertise while at the same time

generating Resort

a

common agreement on worthwhile

,%ction.

practical

to bureaucratic methods or to formal systems analysis

unsatisfactory for a variety of reasons.

The procedure of

is

agro­

ecosystem analysis which is described and illustrated here steers

a

combining a rigorous framework with sufficient

middle course,

to encourage genuine interdisciplinary

flexibility

interaction.

This procedure has been designed and tested in several

workshops

held in Thailand over the past five years.

At system,

the

of

the procedure are the

hierarchies,

system

ecosystem. the

heart

system

concepts

properties and

the

of

the

agro­

The participarts begin by defining the objectives

analysis

and

the relevant systems,

their

boundaries

of and

hierarchic arrangement. This is followed by pattern analysis, the

systems terms

being analysed by all the participating of space,

time,

flows and decisions.

disciplines

in

These patterns are

important in determining the important system properties of agro­ ecosystems,

namely productivity,

stability,

nustainability and

equitability. The outcome of the analyses are a set of agireed ke"

questions for future research or alternatively a set of tentative

guidelines for development.

Experience suggests that the procedure can be applied at any

3

time

a

in

project's life,

but is particularly useful

at

the

beginning when data are scarce. Ideally it should be repeated and

updaced at regular intervals.

INTRODUCTION

Farmers,

of necessity,

adopt a multidisciplinary, holistic

approach to their work and it would seem logical that this should

to

apply

also

limited

of factors - hiqh yielding varieties of key food

grains,

water,

irrigation

pesticides,

fertilisers,

last

and

holistic

content

of

It is only

in

to

a

agricultural

and

and development and for the formulation of methods

procedures by which this can be achieved. such

provision

decade that there has been a significant demand for

multidisciplinary

research

one

the

- which promise a quick and high return.

credit

way,

a

on

the most part they have tended to focus

for

number

more

(LDC's).

m.ny programmes have approached their goals in this

Indeed

the

ag icultural

of

implementation

programmes in the less developed countries

development

but

the design and

In this pap r I report

practised

in

the justification for a more holistic approach

to

procedure which has been developed

and

Thailand over the past five years.

THE CASE FOR A HOLISTIC APPROACH

Part

of

agricultural

development lies in the recent performance

agricultural

revolution that has been taking place in the

since

World War II.

of

the

LDC's

While real and gratifying increases in per

4

(up by about 8%

food production have been achieved

capita

the incre­

the early 1960's for the LDC's as a whole, FAO, 1977), mental

lution depends have begun to diminish. for

this.

logies

the technologies were

to

Even when conditions are considered favourable, performance

The

on

the

field

IRRI,1979b), 1981),

has proved highly persistent

pest,

disease

sometimes

and

weed

1976).

between

in

the

(IRR1,1978,1979a).

numbei

of

These include increasing

problems

aggravated by pesticide use

(Nickel,1973;

(IRRI,1980,

increased indebtedness and inequity (Collier,1977;

Collier et al.,1974; Finally

Murdoch,1980;

Palmer,1976;

Pearse,1980).

the oil crisis of the mid 1970's generated soaring costs

precisely those inputs on which incteased agricultural

uction was becoming dependent. the

and

the

deterioration in soil structure and fertility (Hauri,1974;

McNeil,1972),

of

the gap

agricultural research station

serious short and medium term problems. of

for

(IRRI,

new technologies have also been accompanied by a

incidence

primarily

they have been slow to spread

the poorer farmers and the more marginal areas

farmer's

!ochno­

for the better favoured classes of farmer and

best endowed agroclimatic regions;

revo­

There are several reasons

Since the beginning the adoption of the new

has been highly uneven;

designed

the

to the varieties and inputs on which

returns

since

The potential returns relative to

costs of inputs have become less dramatic and in many

inputs,

even

prod­

if still profitable,

cases

are no longer affordable

by

farners with poor access to credit.

One problems

answer

aas

been to tackle these

individually as they arise.

5

various

issues

However there has been

and

a

of the problems are

if not all,

realisation that many,

growing

essentially systemic in nature; they are linked to each other and

Moreover they arise

to the performance of the system as a whole. as

It is, of course, almost axiomatic that revo­

logical elements.

or otherwise,

agricultural

lutions,

involve such incompatabil­

ities.

The

size and magnitude of change is of the

sticcess

and

undue preoccupation with problems and

may impede the realisation of the main objectives.

directly

they

threaten

the

main

of

essence

side-effects

Nevertheless,

great

experience suggests that the problems are often so

recent that

techno­

introduced

agricultural systems and the newly

existing

tle

between

consequenze of fundamental incompatabilities

a

themselves

objectives

Even where there is some success in

(Conway and McCauley,1983).

if

lived

the success may be short

attaining

increased yields,

attention

is not quickly diverted to side effects which threaten

other equally important development goals.

The last decade has also been characterised by the return of

large

numbers of LDC agricultural scientists in the induscrialised countries with,

studies training

postgraduate

from

far too often,

which reflects the increasing degree of

specialisation

As

that characterises much of modern agricultural education. consequence agricultural problers often lines,

in

they

are

the

often overwhelmed by

6 velopment

issues

and find it

purely disciplinary terms.

comple.ity

there

in practice

physical

proximity within a

faculty or agricultural research station.

a

of

treat

to

easier

little or no interaction betweei. the agricultural notwithstanding

a

is

discip­

university

It is true that

many

recent technological advances have been made by multidisciplinary

6

but for the most part these were small teams, with narrow

teams,

goals and composed of a limited range of traditional agricultural

Contemporary

disciplines.

problems require teams which have

broader perspective and draw on a wider range of disciplines,

a

in

particular spanning the natural and social sciences. it

The argument,

dispense wizh or by-pass specialisation. agricultural systems, requires

ding

Given the complexity of understan­

anything more than a superficial

the insight,; of highly trained specialists of

all

Compared to the farmer the agricultural specialist has a

kinds.

of knoledge,

range

narrower

more complete.

range,

There

is

within

deeper and,

which is

where

But

its knows

much that the specialist

farmer is ignorant of and could use.

the

that

not that we should

is

should be stressed,

the

farmer tends to be superior, not least at the practical level, is in

overlap

of knowledge where the

areas

those

(Figure

disciplines

specialist

that

1) and it is precisely in such areas

the

current problems of agricultural development lie.

response

One research

('SR)

has been the development of

(Gilhert et al.,1990;

al.,1981).

Shaner

et

system

for

research

Norman,1980;

Harwood,1979;

and

the

as

This focusses on the farm and development

..

y,;tems

tarming

seeks,

through

Ibasic

the

sequential stages of analysis, design, testing and evaluation, to discover and implement technological improvements that are appro­ priate

the farm's capacities and capable of

to

constraints. response

This

approach

aro!;s

primarily

to the problems of small farms

characterised

overcoming as

a

its

specific

in the LDC's and is also

by a strong involvement of the

farmers

themselves

capitalising on their knowledge of

at all stages in the process, and

problems

goals and their capacities

as

and

experimenters

innovators.

A second approach has been that of integrated rural develop­ ment

(IRD) (Conde et al.,1979; FAO,1975; Gomez and Juliano,1978).

This is even more holistic in scope but directed primarily toward

the

development

Its

focus

end of the research and the organisation of

is

spectrum.

development

deliberately

go beyond a consideration of Zhe needs of

agricultural

production

forest

fish,

off-farm employment, and

other

communal

and hetter provision of In practice

services.

increased

more opportunities

projects

IRD

for

education

health,

as a means of improving coordination

seen

commonly

improved

to encompass such aspects as

and handcraft production,

which

projects

development

and

are

better

working relations between different government agencies.

Both

these

approaches

have

proved

practical

of

The major problem

they are not without their critics.

although they face,

value,

which is common to all holistic research and develop­ is that of trying to encompass a

breadth

of

ment

enterprises,

view

and range of disciplines and talents while at the same time

research

and

bureaucratic research likely

on sorthwhile practical acion

a common agreemen

generating

development. procedures

One solution has been

and

or development team.

hierarchic

a

leadership

of

This may be effici-nt but it

to become rigid and non-innovative with time, anc

rely

to

cross-fertilisation

valuable

insights

possible

with a multiiisciplinary group.

for

on

the

is

losing the

that

is

An alternative is

to

of

ideas

rely on formal techniques of systems analysis, using mat iematical

8

FARMER'S KNOWLEDGE

DISCIPLINE B

DISCIPLINE A

FIGURE

Ov-rlapping )nowledge bhrtwoen farmers and research qpecialists ( eq soil s:ientists and agricultural I1tched .nd striped areas indicate ecoiomists). extent o ke ' 'd r ,

9

or

requiring

of

drawback

But this has the

models.

computer

relatively specialised skills, so excluding the breadth of exper­ approach

of the research and development workers whom the

ience

is meant to involve and help.

I report here

procedure

The

of

concepts

thus rigorous and well focussed.

analysis and is

middle

intended to steer a

developed from tha basic

is

It

course.

is

systems

Yet it is also

flexible in design and encourages wide and easy participation and the

and,

approaches

be

can

that

technique

procedure

The

an alternative to FSR or 1RD but is

an

intended

ideas and insights.

new

of

flow

indeed,

used

within

the

offered of

framework

not

is as

these

in any multidirciplinary research

development programme whether the focus be the crop,

a

and

field plot,

farm, village, watershed, or region. In

paper I describe the underlying philosophy of

this and

examples

of its application,

recently

in Thailand.

Systems Project (1982a, the

some

drawn from several workshops

held

will

findings

then

Detailed reports un thoce workshop-

Gypiantasiri et al.

in

published

qive

the details of the procedure and

approach

the

1982b).

(1980) and KKU--Ford

Cropping

Summaries and a discussion

be presentcd in two further papers

are

in

of

this

series.

THE CONCEPTUAL BASIS

The

goal

interaction significantly

of multidisciplinary analysis is

to

achieve

an

between the disciplines that produces insights which

transcend

those of

10

the

individual

disciplines.

the

Arranging

but

prerequisite, too

among the disciplines

communication

of

ease

physical or social environment so as is

essential

an

the process of interaction may remain casual,

mundane.

and

producing results that are superficial

often

promote

to

Experience suggests that the generation of good interdisciplinary

also requires organising concepts and frameworks and

insights

formal

relatively

a

engi­

working procedure which encourages and

neers cross-disciplinary exchange.

concepts

The

have

to be simple and basic

involve

and

a

minimal set of assumptions that are acceptable to all the discip­ participating in the exercise.

lines

At the core of

pro­

the

cedure reported here is the concept of the system and the related

agro­

system properties and the

system hierarzhy,

of

concepts

ecosystem.

coi'­

system is here defined as an assemblage of elements

A

tained within a boundary such that the elements within the dary

other,

have strong functional relationships with each

limited,

weak

or

other assemblages;

but in

elements

non-existent relationships with

the combined outcome of the strong functional

within

relationships

boun­

the boundlry is to produce

a

distinctive

behaviour of the assemblage such that it responds to many stimuli

as a whole, even if the* stimulus is only applied to one part.

We

can

hierarchy

conceive of

such

of the natural living world as systems

nested

a

(gene-cell-tissue-organ-organism­

population-community-ecosystem-biome-biosphere) each with a

more

or less well defined boundary and a distinctive system behaviour.

It trol

is assumed that systems higher in the hierarchy tend to those

b2neath

most important for the

them and,

11

task

con­ of

not readily

the behaviour of higher systems is

analysis,

that

discerned

simply from a study of the behaviour of lower systems

Milsum,1972;

(Checkland,1981;

system properties: properties

These

productivity,

stability and sustainability.

are relatively easy to

productivity

disturbances

free from variability

is

in

small

by

caused

and

inherent in the normal fluctuations of climate

other environmental variables; by

not

although

Stability is the degree to

numbers or biomass per unit of time. which

define,

Productivity is the net increment

easy to measure.

equally

three

the system behaviour can be disassembled into

ecosystems)

and

communities

the three ecological systems (populations,

For

al.,1969).

Simon,1972; Whyte et

it is most conveniently measured

the reciprocal of the coefficient of variation in numbers or

biomass. system

Sustainability

can

be

defined as the ability

to maintain productivity in spite of a major

of a

disturbance

such as is caused by intensive stress or a large perturbation. stress is here defined as a regular,

sometimes continuous, rela­

tively small and predictable disturbance, of soil salinity.

A

A perturbation is an

for example the effect

infrequent,

irregular,

relatively large and unpredictable disturbance, such as is caused

by

a rare drought or flood.

Satisfactory methods of

sustainability have still to be found,

however.

measuring

Lack of sustai­

nability may be indicated by declining productivity but, equally,

collapse may come suddenly and without warning.

In

aqricultural development, ecosystems are transformed into

hybrid

agroecosystems

tion.

These

for the purpose of food or fibre

too can be arranged in a hierarchic

12

scheme

produc­ (e.g.

IRRIGATION

vDYKE

~DK

Competi ;on

MICROORGANISMS

SOIL& WATER NUTRIENTS

Competition

competition

Competition

ISH.

RIC

(%

WEDSL 4-

*C+ANTSS u

u

Herbivory

PESTS Predation

NATURAL ENEMIES

FIGURE 2

V

Representation of a ricefield as a systerm showing key and functional relationsh.ips elments

13

HIGii

LOW

Time

Time

Time

Time

PRODUCTIVITY

STABILITY

Perturbation

Perturbation

Stress

Stress

EQUITABILITY

Time

Time

SUSTAINABILITY

Time

Time

Income

Income

o.

M.

FIGURE 3

The system

propeities of agroecosystems

14

field-farm-village-watershed-regi on). involves clearly

several significant changes. defined,

at

least

the

nelled. many

linkages

The

irrigation

biological

and

These become sharper and less per­

with other systems are limited and

and various

physico-chemical

example is the ricefield (Figure 2): forms

their

more

chan­

s jtems are also simplified by the elimination

species

bund

transformation

The systems become

in terms of

physico-chomical boundaries. meable;

The

a strong, inlets

and

elements.

A

of

good

the water-retaining dyke or

easily recognisable boundary, outlets represent some

of

while the

the

limited

outside linkages.

The important system properties remain essentially the same,

except that productivity is now measured in terms of yield or net

income (Figure 3).

In the ricefield productivity is in terms of

rice,

fish and crabs, but the important functional relationships

which

determine this property remain essentially

ecological

in

character, involving competition, herbivory and predation.

However, at the higher levels of the agroecosystem hierarchy

the inclusion of human beings, omic activities, different LDC farm.

their social,

cultural and econ­

reintroduces considerable complexity,

nature.

but of a

Figure 4 orders the components of a

typical

Some of the important functional relationships remain

ecological or, at least in dynamic terms, are analoqous to ecolo­ gical processes. and

predation

For example,

forms of competition,

can be discerned not only in the

mutualism

natural

inter­

actions but also in the socio-cultural and economic interactions.

An

important new system property consequent on the inclusion

human

beings

is equitability.

This expresses how

15

evenly

of

the

products

of

an

beneficiaries; the

agroecosystem are distributed among

its

the more equitable the system the more evenly are

agricultural products shared among the members of,

farm

human

household or a village.

say,

Equitability can he readily

a

des­

cribed using statistical distribution parameters (Figure 3).

In natural ecological systems the operation of natural sele­ ction on the reproductive success of individual organisms favours

numbers,

and hence the productivity of ecological

survival, and hence sustainability. stability, ation,

as

here defined.

operating

replaces

natural

systems,

It may or may not select for

In agroe-osystems human

on both individuals and whole systems, selection.

Different

system

of

possible to view agricultural development as a changes

in

the

relative values

of

the

manipul­ partly

properties

favoured according to predominant human goals and values. thus

and

are

It

is

progression

important

system

propezties.

In general, traditional agricultural systems such as swidden

cultivation

(shifting

cultiviaiton) have low

productivity

and

stability, b,,t high equitability and sustainability (pattern A in

Table I).

Traditional sedentary cropping systems tend to be more

productive and stable, yet retain a high degree of sustainability

and ,:ome of the equitability (B). technology, to

However the introdution of new

while greatly increasing the produczivity, is likely

also lead to lower values of the other properties (C).

This

was particularly true, for example, of the introdution of the new

high yielding rice varieties,

such as IR8 and its relatives,

in

the 1960's; yields fluctuateO widely, but have tended to decline,

16

U

P roduc e mark ets \ Off-farm employent \ Input markets \

PRODUCE

Innovations/Skill

F mily Cap ital

SOCIAL TRAFFIC

Crafts/

I K in 'eighbour

ehb - -- u _ co peatv

Labour Knowledge

Consumer goods

FAR

----

. . . . .

'

a

1

Temple

/

Soils

Crp

Topography

Livestoc

Water

Fish

/Timber

~~Fertilizers Crops



~Pesticides

Livestock ~Seed,Watr

Fish kk

?IGURE 4

Machinery

Timber

Government e -activity/

\/

Welfare _



/

/ /

Comonents of a typic&l less developed ±ndicotinq linkages with other s'stens

17

/

country farm

in

part

due to growing pest and disease

varieties still

combine

high productivity with

have poor sustainabi]ity (D).

attack.

More

high

stability,

recent

but

The ideal goal is probably

pattern E or on marginal lands, where there is a conflict between

productivity

and

sustainability,

pattern

F

may

be

more

appropriate.

THE PROCEDURE OF ANALYSIS

The

procedure has evolved over the past five years from one

originally designed for ecosystem analysis It

rests

(Walker et al.

on the concepts described above and

on

five

1978).

further

assumptions:

1.

It

is

not

necessary to know everything

abcut

an

agro­

ecosystem in order to produce a realistic and useful analysis.

2.

Understanding

agroecosystem

the behaviour and important properties of an

requires

knowledge of only a few

key

functional

relationshios.

3.

Producing significant improvements in the performance of an

agroecosystem

requires

changes

in only a

few

key

management

decisions.

4. and

Identification and understanding of these key relationships

decisions requires that a limited number of appropriate

key

questions are defined and answered.

5.

Since

questions most

there

is,

as

yet,

no easy guide

or identifying key relationships

productive

approach

is for a

18

and

to

defining

key

decisions,

the

multidisciplinary

team

to

OBJECTIVES

1p

SYSTEM DEFINITION

PATTERN ANALYSIS

AND

SYSTEM PROPERTIES

IMPLEMENTATION

FIGURE 5

Basic steps of the procedure for aqroeco,ystem analysis

19

Table

I

Agricultural

development

as

a

function

of

agroecosystem

properties

Productivity A Swidden rultivation

B Traditional

cropping system

LOW

MEDIUM

Stability LOW

MEDIUM

Sustainability

Equitability

HIGH

HIGH

HIGH

MEDIUM

C Improved

HIGH

LOW

LOW

LOW

D £mproved

HIGH

HIGH

LOW

MEDIUM

E ?Ideal (best land)

HIGH

MEDIUM

HIGH

HIGH

MEDIUM

HIGH

HIGH

HIGH

F ?Ideal (marginal

land)

20

attempt

to

system

collectively deFine questions through a process

definition,

analysis of system patterns and the

of

invest­

igation of system properties.

The

basic steps of the procedure are described in Figure 5.

Experience

has

shown that the procedure is best followed

seminar or workshop environment, team

are

small

interspersed

groups

Thailand

of a year,

week,

but

with

acquisition.

1980)

a

whole

sessions involving

Although the first

(Gypmantasiri et al.,

period

The

in which meetings of the

with intensive work

of individuals.

in

workshop

ran intermittently

in

for

a

more recently they have been confingd to one a

month-long

Table II

preparatory

describes an appropriate

period

for

data

timetable.

key to success lies in clear communication between

the

different disciplines present. In the Pattern Analysis phase, in

particular, present

it

their

is importanz for the Participants to

strive

disciplinary and specialist knowledge in such

fashion that all other members of the workshop can easily its

significance.

diagrams and maps, trees,

a

grasp

This process is greatly helped by the use of

in the workshops extensive use has

transects,

to

graphs,

histograms,

been

flow diagrams,

made

of

decision

venn diagrams and any other pictorial device that appears

to aid communication. One practical, but essential, requirement

is

for the workshop room to be well ecaipped with overhead

jectors, transparencies, pin boards, graph paper etc.

21

pro­

Table II

Timetable for a week-long workshop of agroecosystem analysis

Day 1

Participant introductions.

Conceptual basis and details of procedure.

Examples from previous workshop results.

Day 2

System Definition by whole workshop team.

Break into sub-groups, each assicned a level in

the system hierarchy (e.g. field plot-farm-village

-region or one of a series of agroecosystems

(e.g. different farms or villages). Each group

carries out Pattern Analysis and Key Question

Identification.

Day 3

Continuation of Day 2. meetings if necessary).

Day 4

Field visits to agroecouystems.

Day 5

Presentation by subgroups of findings. Whole team discussion of Key Questions Research Design and Implementation.

(Brief whole team

and

Day 6

Continuation of Day 5 as necessary. Writing of draft report by editcrial team.

Day 7

Completion of draft report.

22

OBJECTIVES AND DEFINITIONS

Objectives

As final

in all exercises in systems analysis the quality of resutls

objectives at unambiguous team.

1.

crucially on a having

a

definition

the outset which is couched in simple, language

and

of

precise and

is acceptable to all members

of

the

lead

to

Recent workshops have had objectives of the form:

To

identify

improvements households 2.

depends

the

in

research

priorities

that

the level and stability of

will

net income

of

farm

in the x region.

To identify tentative guidelines

for improving agricultural

productivity of the poor farmers in y village.

Precise

definition of targets is crucial.

objective _r

to

improve mean agricultural productivity of an

the productivity of

the poor farmers in the area

may not imply the latter)? vity only,

For example,

(the

is the

area,

former

Also is the aim to increase producti­

or is improved stability, sustainability or equitabi­

lity to be explicitly included?

System Definition

This phase involves identification of systems,

system boun­

daries and system hierarchies.

At the outset the identificalion of systems and their daries is subjective and physical

boundaries

tentative.

The biological and chemico­

are often fairly clear:

23

boun­

the ricefield

is

bounded

by a dyke; the valley by the cxtent of

the

watershed.

nut

the cultural and socio-economic boundaries ar, r,ore elue;ive.

For

example,

farm - is

itself

defininc a farm household solely in terms -

th.- land that is

frequently

inadequate.

cultivated or sth,=rwise A mc,mber of tr

be deriving income from- f-r away; on

distant

influenced origin.

l

Northaast

ter-.,orari]v in

cassava,

is

Economic

Community

influenced

to translate these, aphic

terms

combine

vale of

Thailand .-embers of theArabia;

by quota,,; estahli -hd

ve'sa.ita

as far as

depend may

a

he

complex:

Familv

way

ho

she price of a major crop, 'v

and the velu-s of Buddhist

influenced by religious

rxooited

the sale of rrodrce ma,

or reliqious movements

S-,di

the

F:rm household may

and the farmer's goals and

politii

by In

working

markets

of

farmers

in Sri L.inka. )o-sible,

European

tho

m,-y

be

The ',rlswr i3

into physical or qeoqr­

and to elaborate system hierarchies that

link

systems whose boundaries are defined in different

or

terms

(Figure 1;. The

systems and boundaries can be revised as

the

workshop

proceeds, particularly in the light of a grow,;ing understanding of

the

system properties since the extent and quantificatios of the

important functional relationships ties

proper­

will provide nore objective criteria upon .:hich to draw the

boundaries. siystems of

contributing to these

The :,rcdIura of analysis will als;o indicate

which

are strong in terms of their relevance to the nbjectives

the workshop

-nd increasingly only these will b

any detail.

24

analysed

in

WORLD

INTERNATIONAL MARKFT

NATION

ECOSYSTEM

PROVINCE

LOCAL MARKET

TRIBE

DISTRICT

MIDDLE MAN

I

I

KIN GROUP

VILLAGE

COOPERATIVE

FAhILY

FAMILY

FARM

COMIUSAL

POLITICAL

ECONOMIC

WATERSHED I

IRRSTIOH

CO.DINITY

FARM

POPULATICN

FIELD

ORGANISM

CROP PLANT

I

ORGAN

CELL

GENE

NATURAL

AGRICULTURAL

FIGURE 6

System hierarchies in a less developed country (Conv;.y 1983)

25

PATTERN ANALYSIS

Four

patterns are chosen as likely to reveal the key

func­

tional relationships that determine system properties.

Three of

these

- space,

time

and flow - are knoan to

be

important

determining the properties of ecological systems (May,19Hl). three are significant factors in productivity.

in

All

Variability or

heterogeneity in space is also an important promoter of stability

and

sustainability (e.g.

Variability in time, long

predator-prey system, , Hass;o 11,197F).

however, can be destabi lisino;

time lags are often very unstable

either

stabilising

or

eystems with

(Mtay, 1975).

Flows

are

destabilising depending on

.h. ther

the

feedback loops are negative or positive (Levins,197.).

All

three

patterns also have the vi rtue of

with respect to scientific disciplines. equally analysis

being

neutral

Space, time and fiow a-o

important patterns for both natural and

social

science

and hence provide a basis for the gmeration of

disciplinary

insights.

The fourth pattern - decisions - arises

directly from the need to understand the consequences manipulation

and

cross­

to identify those decisions which

of bear

human

most

significantly on agroecosystem sustainability and

equitability.

Although this pattern is primarily the ooject

socioesonomic

analysis,

experience

of

shows that it generates lively

discussion

among both social and natural scientists.

Space

Spatial and transects. important

patterns are most readily revealed by simple

maps

Overlay maps are useful in uncovering potentially

functional

relationships.

26

Thus in

the Chiang

Mai

Valley •sity

of Northern Thailand they indicated that cropping was

more a function of the farm irrigation

than soil type (Figure 7).

system

inten­ rather

Subsequent analysis of the pattern of

decision making in irrigation in the Valley suggested that triple

cropping is likely to be more reliable in traditiona'. and tube or

shallow dug well systems because farmers exercise greater control

and hence the water supply is more reliable.

Transects areas

and

within

its

particularly useful in

identifying

problem

the impcrtant spatial relationships both between

farms.

systems

are

In the analysis of Northeast

Thailand

agroeco­

the recognition of the mini-watershed agroecosystem

subdivisions pin-pointed the role of the upper paddy

as the generator of instability in rice production

and

and

fields

(Figure 8).

Time

Patterns in time are best expressed by simple graphs. patterns appear to be important for agroecosystems. that

of

ition

or simultaneous graphing of

credit meters. the

seasonal change and can be analysed by the

peahs,

prices etc.

cropping

Threi

The first is

superimpos­

sequences,

labour,

on various agrometeorological

para­

This helps, in particular, to idenfity those periods in

year where the timing of operations and the availability

of

resources is critical for productivity and stability (Figure 9).

Longer term changes, raphic

parameters etc.,

in prices, production, climate, demog­ can be graphed in a conventional manner

(10 years of data is minimum requirement).

These reveal

in productivity and a measure of stability (Figure 10),

27

trends

possible

I

Single cropping

Rainfed RID systems

Double cropping

L

systems Traditional

Triple cropping

Tube wells i

Dug wells

a.

FIGURE

7

Spatial ,RID)

patterns in the Chi3nq Mij Valley, 'h and non-government irr~rnwion -ys~teis

b.

-

(,

roppiv- -nten-ity, al. 19R0)

(b)

governr.ient

Hamlet

\X\.

-Field

shelter

Upland

Upper Paddy

Lower Paddy

Soils

Paleustult

Paleaquult/ Paleustulc

Paleaquult

Crops

Cassava Kenaf Sugarcane Water melon

Cassava Rice

Rice

followed by

vegetables

Insufficient water

Occasional

flooding

Problems Drought Erosion

FIGURE 8

Upper Paddy

Upland

Transect of a min'watershed in Northeast Thailand

(KKU-Ford Cropping Systems Project 1983a)

29

300-

rainfall

--

-

*v P- apot.silalion

200

,E, "' " too "

--

- -. .----. . . .

.

10

21100n KENAF

NAF

Glutinous rice

2­

o

n

nn

n

Tobacco

Sso80

40

20 aKenaf

4

2

MA

FIGURE 9

M

JJ

A SO0N

D J

FM

A MJ

J

A S

Seasonal pa'.tterns of rainfall, crop-inq and labour demand for an area of Northeast T;ahiland (KKU-Ford Crop[-inq, Systems Project 1982a)

30

10-

10

8­

0 o

t--6

6-6

00

.o

7

•o

oZ

0

­

'Regional rice requirement

1960

1462

19'64

1966

19'68

19'70

I92

19'74

19'76

1978

Year

FIGURE 10

Rice production in Northeast Thailand (KKU-F-d

Foundation Cropping Systems Project 1982a)

31

time

lags in the system and other causes of instability

11) and any signs of lack of sustainability The

final

lier,

posts, diseases

Perturbations include major floods or droughts or

a sudden outbreak of a pest or disease. two

important

Stresses, ar defined ear­

include soil deficiencies and toxicitie2s,

and weeds etc.

the

(Figure 12).

pattern in time is of the response of

variables to stress and perturbation.

(Figure

The distinction between

forms of disturbance rests on the

degree

of

predict­

ability.

In some regions of the world, for example in Northeast

Thailand,

floods

stresses;

in

relatively brown

and

droughts are so common as

to

constitute

Northern Thailand where wet season rice pests

unimportant

an outbreak of a new pest,

such as

planthopper (Nilaparvata lugens) would constitute

turbation.

In

perturbations

the need

analysis actual and possible to

a

or

the

per­

stresses

be identified and the known

are

and

likely

responses of the variables graphed (Figure 13).

Flow

Included

under

this heading are the patterns of flows

transformations of enerqy, the agroecosystems.

and

materials, money, information etc. in

While these may be described by conventional

flow diagrams the aim should not be to trace out all the detailed

relationships. major

causes an

Flows

should

be principally analysed

effects and for the presence of stabilising

destabilising feedback loops.

The flow diagrams should thus

kept as simple as possible (Figure 14). histograms

for

Tables,

matrices,

(Figure 15) and regression graphs may also be

in indicating important relatiornships.

32

the

or

be

bar

useful

o-ci 7-

o---0 -

Cassava Kenaf Maize

!'5­

0

CL

4"

0­

3­ ,0

,

2­

0-1

3

175

19 77

1979

Year

FIGURE 11

Annual fluctuations in price and planLed area for

major crop- in Northeast Thailand (22 baht = US$1

ap'rc-"; 1 rai. = .16 ha) (! KU-Ford Cropping Systrms Projocc 1982a)

33

7.0

6"0

40­ "

-

I

1969

II

71

I

73

I

75

I

I

77

I

79

Years

rIGURE 12

Declining rice yields under intensiv-i cropping cn iiresearch staLion in Northern Thailand (Gypmantasiri el al. 1980

34

CROP I

6"5

II

CROP 2

I CROP3

I

rice- soybean- mungbean

rice-soybean- fallow

SOIL

FLOODED

alo

,c rie-a

,,

pH 5.5 •

*

I *

4.5

I

',

4.0

AS

O

N

FIGURE 13

D

F

J

A

M

J

J

A

SON

D

Fluctuations in soil acidity under three cropping systems in Northe':n Thailand (plH measured 4n 0.01M CaCd ) (Gypmantas~ri et al. 1980)

t

I+

- -.-.-.Urban Poorjt - -

I

I

- I

+

Early rain

+

+

+

Planted area

+

I

-

Ric-/ capita

+

Late

Labour

I

Yield

Production per farm

FIGURE 14

rain

Flow diagram of

rico

production, economics and labour

relations

Northeast Thaiilnd

35

for

Decisions

Decisions,

ranging from those of national agricultural po­

licy to the individual farmer's day-to-day choices,

occur at aIll

levels

in the hierarchy of agroecosystems.

important. The

Two

patterns

first is of the choices made in a

given

are

agro­

ecosystem

under differing conditions and is best drscribed

by

means

a decision tree.

to

of

Construction of the tr.

helps

reveal both the goals of the decision maker and the constraints

on choice that are present in the agroecosystem. produced

for Northeast

importance

Thailand agroecosystems

Decision trees

suggested

the

of labouL irAd land type constraints cn farm and

vil­

lage production (Figure 16).

The sion

second pattern is of the spheres of influence of

makers.

deci­

Here analysis is primarily required in order

to

identify the critical decision makers in the system hierarchy and

simple tact

diagrams are useful in distinguishing the points of con­ and

overlap in decision making.

water control in the Chiang Mai Valley,

Analysis of

irrigation

for example, reveals the

extent of farmer participation in decision making under different

systems

(Figure 17).

SYSTEM PROPERTIES

Discussion pattern

of

analysis,

ships and decisions. phase

it

system properties should guide the form

of

helping to indicate the likely key relation­ However at the end of the pattern analysis

may be useful to summarise what has been

learnt

of

system properties and to tabulate the most important contributing

36

l

Net farm

income:

R= rice, C= cash crop

[II

Trade, home industry, etc.

D]

Off- farm income Income from livestock

26,000

22,000­

18,000-

Ec 14, 000­ 0 U

S

10,000­

. R

6,000

R

R

R

R

R

R

R

R

c

R

R

2,000

Villages

FIGURE 15

Components of far-i income for 16 adjoininq villic,?s in Northeast Thailand (22 baht US$1 zpi)-ox.) (KKU Ford CropPinq Sstomn Project 1982h)

STRATGIES

Io, hi11hquality

No

TOBACCO OR OFF-FAR

NoYe

RIFETobacco

Ooes rice crop

grou

.ndr

cntric,

teet

subsistence?

Yea

TOBACCO OR WATEKMLON

oes soil require

improvement?

YesRice-w~te

Ys

LATheNLOs

H

e

-

IAuon-bend

sroNntontinusly

Does dIsLa,,.

bud

p? Ye.

Rotatiion )f ricert,-n j I'll lo-d by too or,, 11.

FIGURE 16

Decision tree For farviinr str,.eqirs of Northeast Thai]and 37

ly

irl on

area

a.

Catchment

RID [lead office

Dam 6 laterals"'

Project Engineer Water MIasters

- - --- -Zonemnen C'ate Tenders

Waters users assocn.

-.

Sublateral

Common irrigator

Farm ditch

Field ditch

Farmer

Catchment

Annual meeting of

muang leaders

Dam

i

laterals

&

.

t "

"

....

Village headman

Farm ditch

Fa me r

Field ditch

FIGURE 17

Diarriim so:'iC points of rontaclt ,idovorl;ip in .rrigtioi Ceuision ,ckrtj North,ri 'Thaiilond: (a) 4ov,.njent (R.D) ,.ystoms; (b) tririt.Jonal nystems (.n each diagram the physical systems are .;nthe left and the deciior. making systems on the

riqht).

36

relationships and variables

(Table III).

KEY QUESTIONS

Key question3 arise throughout the procedure, during system

definition,

pattern

perties. They

analysis and the discussion of system

should

be

noted down as they emerge

and

collectively revised by the members of the subgroup in the of

all

the information available.

pro­ then

light

Experience suqgests that

a

field trip to the agroecosystem sites is useful at this stage:

some questions may be quickly answered; others may be revealed as

poorly

based

should

then

or

inappropriate.

The full list of key questions

be extensively discussed by the workshop team as a

whole.

Experience shows that the questions take a variety of forms.

In many, if not most, situations the analysis is likely to reveal

broad

gaps in knowledge which require further

uncover suspected key functional relationships.

investigation

to

A typical

gap

parameters

for

question is:

"What

are

the

most appropriate meteorological

characterising the agricultural seasons in the Valley?"

(In four

the Chiang Mai Valley farmers appear to recognise distinct cropping seasons but their meteorological

at

least

defini­

tion is not clear.)

However most questions will be more narrowly defined, focus­ sing on suspected key processes or decisions. For example:

"Can

new rice varieties be bred to produce more stable yields on

the upper poorly watered paddy fields?"

39

Table

III

Examples

of

key

relationships

and

variables

determining the system properties of agroecosystems of Northeast

Thailand.

PRODUCTIVITY

Demand by world markets (especially EEC)

Government rice and fertilizer policies

Water resource development

STABILITY

Rainfall, especially floods and droughts

Rice production in upper paddy fields

Human migration

Diversification of production

SUSTAINABILITY

Increasing salinity

Increasing indebtedness

Deterioration of communal mutual help arrangements

EQUITABILITY

Subsistence rice crop

Diversification of production

Government rural works programme

Availability of credit

40

(The

high

largely

instability of rice yields in Northeast Thailand

a function of poor performance in the upper

is

elevation

fields and of the mini watersheds.); or

"What

is the optimal application

of fertilizers to

traditional

rice varieties under highly variable rain-fed conditions?"

(In Northeast Thailand rainfall is highly variable and it is

not

clear that encouragement of higher fertilizer use would produce a

reasonable return to the farmer or to the region.)

Many important questions span different levels in the system

hierarchy. For example:

"How

is

Chiang

the

form and productivity of crcpping systems in

the

Mai Valley affected by government policy on the price

of

rice?"

(Various government price policies essentially mean that farmers

get

a

relatively poor retu.n for rice,

the basic crop of

most

existing cropping systems.)

However

in our experience the most powerful

questions are

those that directly address system properties and in

particular

the actual or potential trade-offs between them:

"To

what extent are the gains in productivity and stability from

land

consolidation in the Chiang Mai Valley likely to be

offset

by a decline in sustainability and equitability?"

(Land

fragmentation in the Valley, although promoting

ineffic­

iency, seems also to encourage crop diversity and hence sustaina­ bility. kind

It is also probably more equitable.)

Questions of this

also often implicitly raise doubts about the

wisdom.

41

conventional

Where the object of analysis is to identify possible ways of

developing

an

agroecosystem the key questions may be framed in

the form of tentative guidelines:

"It is likely that crop production in village x will be signif­ icantly

improved by the provision of bctter quality second

-rop

seed."

(Under intensive rotational cropping good establishment second

crop

written

following rice is critical to

of

success.)

the

Although

in this form, t.ie implicit question aod hypothesis

apparent. strictly

are

If better quality seed is provided it should be

seen

as

an

experiment and the results used to

modify the

overall analysis.

As

far as possible the key questions should be turned

carefully workshop

phrased, test there

hypotheses so that by the end

is a list of questions each

into

of

accompanied

the

by

a

hypothesis, a discussion of the issues involved and some indicat­ ion of the investigations now required.

RESEARCH DESIGN AND IMPLEMENTATION

The remaining phase of the procedure is one of

conventional

research. The hypotheses are tested as appropriate: by laboratory

or

field experiments, field surveys or extension trials,

or by

development trials in which guidelines are enacted and assessed.

The

multidisciplinary

_ctivity of the workshop may or

may not

extend into the research phase; many of the key questions will be

phrased the

in terms of single disciplines and are best answered

appropriate specialists.

by

T-, this extent the outcome of the

workshop may appear superficially similar ts research programmes

42

arising

from a collection of individual initiatives,

but

will

crucially differ in that the individual research projects are the

direct

consequence

of a multidisciplinary systems analysis

the results feed back to and modify that analysis. has

thus

a

The

better contextual basis and is likely

to

and

research

be

more

appropriate and relevant, while the results have a greater chance

of being acted upon.

It is,

of course,

not necessary that all the key questions

be tackled by the workshop team.

Some of the questions may raise

issues or require methods of approach that lie outside the compe­ tence

of

their

importance

the group

But if the questions are well phrased

clearly

justified they

should

and

interest nd

excite other research workers to find answers.

DISCUSSION

Figure

18 shows the final detailed form of

the

procedure.

The arrowed lines connecting the various stages indicate that the

procedure is intended to be itera-ive. New knowledge and perspec­ tives

at

stages;

each stage are likely to require revision

earlier

in particular answers to the key questions when they are

found will modify earlier assumptions, vals.

of

Experience

updated at regular inter­

suggests that the procedure can be applied

at

any time in a project's life but it is particularly useful at the

beginning of a project when data are scarce. Ideally it should be

repeated through

and of

updated

at regular intervals.

Phe

first

run­

the procedure is likely to produce more

"gap"

than

43

SYSTEH

DEFINITION

OUNAI

CIIY

SPACE4-

---------- - I

E

PATTERN ANlALYS IS

FLOW< 4-

-

ECI SI 01S

IZY

QUESTIONS

GUIDELINES

HYPOTHCSES

DESIGN

AND

IMPLEMENTATION

FTGURE 18

Th'

LABORATORy i:XI-L:Rl . ILTS FIFLD EXPERIMENTS F I ILLDSUKVEYS

EXTENSION?TRIALS

OLVELOIPHLNT[:XI'ERI.,fE [S

fu.ll prou. dure of : Crccosystem analysis

.'.

4

true key questions; but with time and answers the original ques­ tions will be replaced by better,

more precisely focussed

ques­

tions.

It

should be stressed that the procedure is intended to

flexible.

Our

experience is that it changes in quite important

respects from workshop to workshop, of

be

the workshop and the background,

the participants.

depending on the

objectives

experience and interest

of

New ways of presenting, analysing and interp­

reting information should be actively encouraged.

Despite the

its foundation on the concepts of systems

procedure

atical

analysis

makes no explicit mention of the role of

models.

We

have deliberately avoided

tne

mathem­

conventional

approach of using a large scale simulation model as the focus analysis. luded to

This

is partly because many individuals

may be

from the analysis through a lack of skill or

interact

with the model,

and partly because in

of

exc­

inclination

such

large

scale modelling exercises the key issues and questions tend to he

obscured

by

Nevertheless

a preoccupation with the details of it

variety of models models,

construction.

is clear that the potential for use of (matrix models,

simulation models etc.)

a wide

regression, linear programming

exists throughout the procedure,

for example in the analysir of the patterns of time,

space, flow

and decisions and of the dynamics of system properties, in formu­ lating key questions and hypotheses and, indeed, in some cases in

answering used

in

these practice

questions.

The extent to which models will be

depends on the interests and

workshop participants.

45

skills

of

the

ACKNOWLEDGEMENTS

the people.

workshops have involved a total of well over a hundred

Those

most

involved in the development and refining

the procedure are Dr.

Terd Charoenwatana,

Mr.

of

lain Craig, Ms.

Laxmi Ganjapan, Dr. Terry Grandstaff, Mr. Phrek Gypmantasiri, Dr.

Rapeepan Jaisaatd,

Dr. Viriya Limpinuntana, Dr. Aran Patanothai,

Dr.

Benjavan Rerkasem,

Ms.

Nongluk Suphanchaimat and Ms.

Dr.

Kanok Rerkasem, Dr. Manu Seetisarn,

Aree Wiboonbongse.

Financial

support for the workshops was provided by the Ford Foundation c.nd

in one case by the US Agency for International Development.

46

REFERENCES'

Checkland,

P.,198l. Systems Thinking,

Systems Practice.

John

Wiley & Sons, Chichester.

Collier, W.L.,1977. Technology and peasant production: ssion.

Collier,

a discu­

Development and Change 8: 351-362.

W.L.,

Soentoro, Wiradi, G. aid ilakali,1974.

Agricul­

tural technology and institutional change in Java. Food Research

Institute Studies 13: 169-194.

Conde,

J., Paraiso, M.J. and Ayassou, V.K.,1979. The Integrated

Approach to Rural Development Health and Population.

Development

Centre Studies, Development Centre of the O.E.C.D., Paris.

Conway,

G.R.,1983.

Applying

Ecology.

Centre for Environmc.*tal

Technology, Imperial College of Science and Technology, London.

Conway,

G.R. and McCauley,

D.S.,1983.

Intensifying

agriculture: the Indonesian experience.

Nature 302:

tropical

288-289.

F.A.0.,1975. Integrated Rural Development.

Food & Agriculture

Organisation, Rome.

F.A.0.,1977. The Fourth World Food Survey. Organisation,

Rome. Statistic

Food & Agriculture

Series No.11, Food & Nutrition

Series No.10, 128 pp.

Gilbert,

E.H.,Norman,D.W. and Winch, F.E.,1980. Farming systems

research: a critical appraisal. MSU Rural Development Paper no 6.

Department of Agricultural Economics, Michigan State University,

47

East Lansing, Michigan.

Gomez, A.A. ani Juliano, P.A. (Editors),1978. The Philippine Experience. Rural

Rural Development:

The Philippine Training Centers for

Development, University of the Philippines at Los

Banos,

College, Laguna.

Gypmantasiri,P.,Wiboonpongse,A.,Rerkasem,B.,Craig,I.,Rerkasem,K.,

Ganjapan,L.,

Titayawan,M.,

Seetisarn,M., Thani,P., Jaisaard,R.,

Ongprasert,S.,Radanachaless,T., and disciplinary Valley:

Conway,G.R,1980.

An Inter­

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