Land Resources and Productivity Potential - Agro-Ecological Methodology for Agriculture Development Planning

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NOT FOR QUOTATION WITHOUT PERMISSION

OF THE AUTHOR

LAND RESOURCES AND PRODUCTIVITY POTENTlAL

-

AGRC&ECOLDGICAL MEI'HODOLOGY

FDR AGRICUL- DEYELOPMEXT PLANNING

M.M.Shah G.M. Higgins AH. Kassam G. Fischer

March 1985 CP-85-14

C o l l a b o r d w e Fhpers report work which has not been performed solely at t h e International Institute for Applied Systems Analysis and which has received only limited review. Views or opinions expressed herein do not necessarily represent those of the Institute, its National Member Organizations, or other organizations supporting the work.

TNTEFWATIONAL INSTITUTE FOR APPLIED SYSTEMS ANALYSIS 2361 Laxenburg. Austria

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L A N D RESOURCES AND PRODUCTIVITY POTENTIAL AGRO-ECOLOGICAL METHODOLOGY

FOR AGRICULTURAL DEVELOPMENT PLA.NNING

M.M. Shah, G.M. Higgins, A.H. Kassam and G. Fischer

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Understanding the nature and dimension of the land and water resources for food and agriculture development and the policies available to develop them have been the focal point of the work of the Land and Water Division of the Food and Agricultural Organization of the United Nations and the Food and Agricul- ture Program a t the International Institute for Applied Systems Analysis.

As we anticipate over the coming decades a technological transformation of agriculture which will be constrained by resource limitations and which could have serious environmental consequences, a number of important questions arise.

(a) What is the stable, sustainable production potential of the world? of regions? of nations?

(b) How does this production potential in specific areas (within countries as well as groups of countries) compare to the food requirements of the future populations of these areas? potential?

(c) What alternative transition paths are available to reach desirable levels of this production potential?

(d) What are the sustainable and efficient combinations of techniques of food production?

(e) What are the resource requirements of such techniques?

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(f) What a r e t h e policy implications a t national, regional and global levels of sustainabili ty?

Stability a n d sustainability a r e both desirable properties of agricultural land resources development, inter-generational equity a s well as of political stability a n d peace.

We hold ecological considerations t o be of critical importance in answering the questions posed above. Limits t o food production a r e s e t by soil and climatic conditions a n d by t h e use, a n d management, of t h e land. In t h e long term, any "mining" of l a n d beyond these limits will r e s u l t in degradation a n d decreased productivity. Accordingly, t h e r e a r e critical levels of production obtainable, in perpetuity, from any given land a r e a a n d h e n c e critical levels of populations t h a t c a n be supported from this area. It is crucial t o take account of t h e physical resource base for potential production a s well a s t h e socio- economic aspects t h a t will influence t h e a c t u a l production.

The population a n d land resources study, c a r r i e d o u t by the Food a n d Agri- culture Organization of the United Nations in collaboration with t h e Interna- tional Institute for Applied Systems Analysis, with funding from t h e United Nations Fund for Population Activities, is concerned with the quantitative evaluation of t h e land resources' food productive capacity on t h e basis of soil.

climate a n d crop d a t a under specifled technological conditions. The methodology and resource d a t a base developed within this study provides a first approximation of t h e food production potentials a n d t h e population supporting potentials for 117 countries in five regions of t h e developing world.

The most fruitful a n d promising avenue for f u r t h e r work and application of t h e methodology is in relation t o detailed country c a s e studies. The aim of this report is to describe t h e agro-ecological methodology a n d specify t h e data needs, with special emphasis on methodological a n d d a t a refinements for

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detailed country agricultural planning studies. The report should be of particular interest and u s e t o institutions in countries considering an ecological- technological-economic approach to t h e planning of agricultural development.

R.J.Duda1 Director

Land and Water Division FAO, Rome

K.S.Parikh Leader

Food and Agriculture Program IIASA, Laxenburg

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The population of the developing countries was 1.7 billion in 1950. Today it is 3.8 billion and by the year 2000 it is expected to be 4.9 billion. Looking even further ahead, by the year 2100, when most countries are expected to have reached stationary population levels, the present-day developing countries will have a population of 8.8 billion out of an expected world population of 10.2 billion.

Many developing countries have in recent years been unable to expand their food production fast enough to keep up with increasing demand, stemming from rising incomes as well as population growth. There is considerable concern a t their diminishing self-sufficiency and food security, and the consequent increase in their import requirements.

Though the major obstacles to increasing agricultural production in many developing countries is shortage of capital investment, modern inputs, skills and research capabilitiy, the limitation of the natural resource base, production potential of soil and climate, is also important. The strategy for agricultural development: which area to develop, how much investment to put. which crops to promote, what level of farming technology is appropriate, depend on the land and climate resources in each country.

Economists customarily assume that under competitive production arrangements t h e best land will be cultivated first. Yet within a country, the historical legacy of settlement patterns, the changing technology, such as development of a new high yielding variety for a particular crop, changing price

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structure, etc. can easily lead to a situation where a country may be putting in resources to develop a not so productive region when another region offers a much greater potential.

Thus a knowledge of the production potential of different areas of a country, suitability of its soil and climate for different crops and potential output that can be obtained under different levels of input intensification is valuable for guiding current policies.

There is an urgent need for each country to look a t its long-term food and agricultural requirements and assess them against the possibilities of sustainable production from its own land resources. Any shortfalls in this will have to be made up by imports which in turn will have to be financed by appropriate exports.

The extent to which land resources of terrain, soil. climate and water, can be utilized to produce food and agricultural products is limited The ecological limits of production are set by soil and climatic conditions as well as by the specific inputs and management applied Any "mining" of land resources beyond these ecological limits will, in the long run, only result in degradation and ever-decreasing productivity of land and of inputs, unless due attention is paid to the conservation and enhancement of the natural resource base.

The agro-ecological zone

(AEZ)

methodology is concerned with the quantitative evaluation of t h e land resourcesm food and agricultural productive capacity on the basis of land (soil and climate) resources and technological options.

This report describes the AEZ methodology and the resource data base in relation to:

Assessment of food production and population supporting potential (Phase 1)

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Planning of agricultural development

-

Detailed country studies (Phase 2).

Phase 1 of the study was concerned with the development of t h e methodology and resource data base for 117 developing countries in Central America, South America, Southeast Asia and Southwest Asia The computerized land resources data base for these countries was developed from an overlay of a climatic map

--

providing spatial information on temperature and moisture conditions onto the FAO/UNESCO World Soil Map

--

providing spatial d a t a on soil type, phase. texture a n d slope. Each area of similar soil and climatic conditions was identified and termed an agro-ecological cell (10,000 hectares).

The Phase 1 methodology of t h e study essentially involved assessing the potential rainfed food production by comparing the soil and climatic characteristics of the land resources in each country with the growth requirements of 17 major food crops and livestock (from grassland). The estimates a r e based on agroeconomic principles and a hierarchic scheme of refinement which integrates soil, climate a n d genetic data to arrive at yield input relationship for a given crop in a given soil under a given climate. These production potentials were estimated a t t h r e e alternative levels of farming technology. A specific crop was chosen for each agro-ecological cell and the rainfed potential production together with irrigated production for the present (year 1975) and projected (year 2000) time periods was converted into food nutrients and, by reference t o p e r caput human food requirements, t o the physical potential of land resources t o support present and projected populations. These results were used to identify and pinpoint localities where land resources a r e a n d / o r will be insufficient t o meet the food needs of present and future populations a s well as areas with surplus potential. The methodology, results and policy implications of this "first" approximation of the food production and population supporting

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potential of the countries in the five regions of the developing world is presented elsewhere.

*

Phase 2 of the study is concerned with the refinement of the AEZ methodology and t h e resource base to enable planning of agricultural development a t a detailed country level. One detailed country study

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^Kenya

--

is presently being carried out by FA0 and IIASA in collaboation with the Government of Kenya.

Using this country study as an example, this report illustrates the type of methodological and resource data base refinements that are necessary to facilitate the integration of ecological, technological, social. demograhic and economic considerations for viable and sustainable agricultural development planning in a country.

The coming two decades and beyond will see an ever increasing number of mouths to be fed in the developing world and only with integrated ecological and socioeconomic studies will i t be possible to adequately plan and provide for the well-being of future populations in the developing world on a sound environmental basis. This report, describing the agro-ecological zone methodology and the compilation of the resource data base, should be of particular interest to technicians and planners considering an ecological-technological-economic approach to planning of sustainable and viable agricultural development.

*Shah, M.M., Fiacher, G., Higgins, G.M. and Ksasam, AH., People, Land and Food Production

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Potentials in the Developing World, submitted for publication as a Research Report, IIASA, Laxenburg.

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CONTENTS

1. Introduction 1.1. Objectives 1.2. Prerequisites

1.3. Detailed Country Studies 2. Overview: AEZ Methodology

2.1. Main Steps in AGZ Methodology 3. Methodology and Data Requirements

3.1. Climate and Soil Resources for Agricultural Production 3.2. Soil and Climate Inventory

3.2.1. Country Refinements and Extension 3.3. Land Use

3.3.1. Country Refinements and Extension

3.4. Land Resources Available for Rainfed Production 3.5. Crops of t h e Study

3.5.1. Country Level Choice of Crops 3.6. Input Levels

3.8.1. Country Level Refinements and Extension 3.7. Crop Production 'Models'

3.7.1. Agro-Climate Suitability 3.7.2. Soil Suitability

3.7.3. Rest Period 3.7.4. Degradation 3.7.5. Wastage

3.7.6. Seed Requirements

3.7.7. Country Refinements and Extensions 3.8. Livestock Production

3.8.1. Country Refinements and Extension 3.8.2. Fish Production

3.9. Land Productivity and Criterion of Crop Choice

3.9.1. Potential Population Supporting Capacity Study

3.9.2. Country Level Food and Agriculture Development Planning Study 4. Concluding Remarks

4.1. Summary of Data Requirements for Country Studies REFERENCES

APPENDIX 1: Numerical Example of t h e Application of t h e AEZ Methodology to an Agro-Ecological Cell

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Table 1:

Table 2:

Table 3:

Table 4:

Table 5:

Table 6:

Table 7a:

Table 7b:

Table 7c:

Table 8:

Table 9:

Table 10:

Table 11:

Table 12:

Soil classification: AEZ study

Characteristics of major climates: AEZ study

Length of growing period zones in number of days when water is available for plant growth

Crops considered in AEZ study Attributes of input levels

Global technology matrix for maize

Maize yields under various climatic conditions and by input level

Limitation soil ratings for maize by input level

Rest period requirements for some major soils according t o climatic and level of input conditions

Assumptions for soil loss/productivity loss relationship Seed requirements: AEZ study

Calorie a n d protein production per h a in smmer rainfall areas from grassland/livestock

Crop distribution by length of growing period zones in warm tropics: by region, 1975

Crop distribution by length of growing period zones, Kenya, 1975

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LIST

OF' FIGURES

Flg. 1:

AEZ

study: methodological framework

Flg .2:

AEZ

country study: methodological framework

Flg.3: Compilation of climate a n d soil inventory-country study Rg.4: Estimation of rainfed land resources: country study Fig.5: Crop production 'model'

F1g.6: Methodology of land degradation hazards: soil erosion and productivity losses: country study

Fig. 7: Compilation of d a t a on r e s t period requirements for crops a n d by regions within a country

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T h i s p a p e r was o r i g i n a l l y p r e p a r e d u n d e r t h e t i t l e " M o d e l l i n g f o r Management" f o r p r e s e n t a t i o n a t a N a t e r R e s e a r c h C e n t r e

(U.K. ) Conference on " R i v e r P o l l u t i o n C o n t r o l " , Oxford, 9 - 1 1 A s r i l , 1979.

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1. r n 0 D U C T I O N

The future of mankind is closely linked with t h e world's capacity t o meet t h e evergrowing demand for agricultural produce. I t is therefore essential t o know this productive capacity as well as the conditions under which i t can be reached.

How can developing countries improve t h e i r food situation? The impor- t a n c e of t h i s question is well reflected by t h e increasing number of studies and reports devoted t o t h e subject. However, with exceptions, s u c h r e p o r t s t e n d t o concentrate on t h e socio-economic aspects of t h e problem and largely ignore o r a t best gloss over t h e question of whether t h e land resources in t h e developing countries a r e adequate for food and agricultural self-sufficiency a s well as exports o r whether t h e productive land resources together with o t h e r available resources can g e n e r a t e sufficient export revenue t o finance t h e necessary food a n d o t h e r imports.

Though t h e major obstacles t o increasing agricultural production in many developing countries is shortage of capital investment, modern inputs, skills a n d research capabilitiy, t h e limitation of t h e n a t u r a l resource base, production potential of soil and climate, is also important. The s t r a t e g y for agricul- t u r a l development: which a r e a t o develop, how much investment t o put, which crops t o promote, what level of farming technology is appropriate etc., depends on t h e land and climate resources in e a c h country.

Economists customarily assume t h a t under competitive production arrangements t h e best land will be cultivated first. Yet within a country, t h e historical legacy of settlement patterns, t h e changing technology, s u c h as development of a new high yielding variety for a particular crop, changing price s t r u c t u r e , etc. can easily lead t o a situation where a country may be putting in resources t o develop a not s o productive region when another region offers a

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much g r e a t e r potential.

Thus a knowledge of t h e production potential of different a r e a s of a country, suitability of i t s soil a n d climate for different crops a n d potential o u t p u t t h a t can be obtained u n d e r different levels of input intensification is valuable for guiding c u r r e n t policies.

Limits t o food production a r e s e t by soil a n d climatic conditions a n d by t h e use, and management, of t h e land. In t h e long term, any 'mining' of land beyond t h e s e limits will r e s u l t in degradation a n d decreased productivity.

Accordingly, t h e r e a r e finite levels of production obtainable, i n perpetuity, from a n y given land a r e a a n d h e n c e c e r t a i n levels of populations t h a t c a n be supported from this area. I t is crucial t o take account of the physical resource base for potential production as well a s t h e socio-economic aspects t h a t will influence t h e actual production.

The agro-ecological zone (AEZ) methodology is concerned with t h e quantitative evaluation of t h e land resources' food and agricultural productive capacity on t h e basis of l a n d (soil a n d climate) resources a n d technological options.

The aim of t h i s report is t o describe t h e AEZ methodology a n d t h e resource d a t a base in relation to:

Assessment of food production a n d population supporting potential (Phase

Planning of agricultural development

-

Detailed country studies (Phase 2)

Phase 1 was concerned with t h e development of the methodology and resource data base for 117 developing countries in Africa, Central America, South America, Southeast Asia and Southwest Asia. The computerized land resources d a t a base for t h e s e c o u n t r i e s was developed from a n overlay of a

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climatic map

--

providing spatial information on temperature and moisture conditions onto the FAO/UNESCO World Soil Map

--

providing spatial data on soil type, phase, texture and slope. Each a r e a of similar soil and climatic conditions was identified and termed an agro-ecological cell (10,000 hectares). The production potential of 17 most widely grown food crops and livestock (from grassland production) was estimated a t t h r e e alternative levels of farming technology for each agro-ecological cell. A specific crop was chosen for each cell and t h e potential production under these different assumptions and for t h e present (year 1975) and projected (year 2000) time periods was converted into food nutrients and, by reference t o per caput human food requirements, t o the physical potential of land resources to support present and projected populations.

These results were used t o identify and pinpoint localities where land resources are insufficient t o meet the food needs of present and future populations a s well a s areas with surplus potential. The methodology and t h e results of this "flrst"

approximation of the population supporting potential of t h e countries in the five regions of t h e developing world h a s been published, FAO/IIASA/UNF'PA (1983).

Phase 2 is concerned with t h e refinement of t h e AEZ methodology and the resource base t o enable planning of agricultural development a t a detailed country level. One detailed country study

--

^Kenya

--

is presently being carried out by FA0 and IIASA in collaboration with the Government of Kenya. Using this country study a s an example, this report illustrates t h e type of methodological and resource data base refinements t h a t a r e necessary to facilitate t h e integration of ecological, technological, demographic and economic considerations for agricultural development planning in a country.

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1.1. Objectives

The overall objective of t h e Phase 1 AEZ study was to estimate the sustainable food and population supporting potentials of land resources under alternative farming technology levels a n d compare t h e s e estimates with d a t a on present and projected populations to identify areas where land resources would be insufficient or surplus to meet t h e food needs of t h e populations.

The study is directed to improving national agricultural policies t o facili- t a t e agricultural development in t h e LDC's. The details of land a n d crops considered a r e necessary for such a purpose. What a r e t h e kind of policy questions t h a t can be answered better by a knowledge of t h e regional, crop-specific production potential of t h e country? For example:

Can t h e country be ever self-sufficient in food production? What a r e the economic costs of various levels of self-sufficiency?

In which crops has t h e country got comparative advantage? Which crops should i t specialize in?

Which areas of t h e country offer maximal r e t u r n t o investments for agricultural development? What incentives for resettlement of populations may be given?

If t h e country wants to impose land ceilings for realizing objectives of equity, what a r e equitable sizes of land holdings i n different parts of the country?

What type of technological development (a high yielding variety of rice or a drought resistant variety of sorghum?) would be most valuable for a country, given i t s resource base?

From t h e assessment of agro-ecological production potential of different countries of the world, some questions of trans-national concern can also be

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explored:

Which s e t of neighbouring countries may cnstitute a natural cooperative unit for food t r a d e and food security?

What levels of international assistance will be needed t o promote a c e r t a i n level of global agricultural development?

The Agro-ecological Zone (AEZ) potential estimates a t the detail t h a t we have made, have some analytical applications. One expects t h a t t h e more a r e a in a country is devoted to a particular crop t h e less suitable i s its land a n d climate for t h a t crop. Econometric estimates of such diminishing r e t u r n s a r e difficult t o make. The AEZ estimates can be used t o obtain estimates of diminishing r e t u r n to a r e a s for different crops (as well as t o inputs). In fact, t h e estimates c a n be used t o identify a complete production possibility surface, albeit implicitly i n t h e form of a linear program, which is not confined t o just p a s t d a t a but embodies f u t u r e potential a s well. This can be of considerable impor- t a n c e for planning agricultural development in many LDC's.

The study has c r e a t e d a physical resource d a t a base suitable for a n assess- m e n t of t h e environmental a n d technological potential for food production of t h e land resources of developing countries. The generated information is par- ticularly relevant for t h e formulation of policies for t h e development of land resources in relation t o t h e f u t u r e size and distribution of populations.

Altogether 117 developing countries/states (51 in Africa, 16 in Southeast Asia, 16 i n Southwest Asia, 13 in South America, 21 i n Central America) have been considered in this study.

1.2. Prerequisites

That t h e study was even considered feasible is due t o n o less t h a n 20 years of prior work, undertaken mainly by t h e stafl of the Soil Resources. Management

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a n d Conservation Service of FAO. This effort resulted, first, in t h e compilation and publication of t h e FAO/UNESCO Soil Map of t h e World (FAO, 1971-81). Con- currently with this work, t h e methodology and framework for land evaluation was developed (FAO, 1976a). The Soil Map and the methodology for land evaluation led t o t h e agro-ecological zone project (FAO, 1978-81). This project was concerned with the assessment of land suitability for t h e production of specific crops in t h e developing world. The results of this project led UNFPA to commis- sion t h e Land Resources for Populations of t h e Future Project, undertaken by FA0 in collaboration with IIASA. to translate t h e food production potentials into assessment of potential population supporting capacities (FAO, 1978-80;

FAO/IIASA/UNFPA. 1983).

1

.a.

Detailed Country Studies

The experience from this study in terms of t h e compilation of the physical potential resource base and t h e development of t h e methdology has illustrated t h e usefulness of this approach t o t h e assessment of t h e environmental a n d technological limitations of cultivatable land resources. Refinements of t h e resource base and extension of t h e methodology suitable for detailed country agricltural planning studies is t h e most promising avenue for f u t u r e work One detailed country case study (Kenya) is already on-going; a t this level of application a major effort is necessary, for example:

(a) To compile a resource inventory a t a finer scale and on a n administrative a r e a basis. In the Kenya detailed case study, a 1:l million soil and climate inventory by district has been developed.

(b) To take account of detailed country land use patterns, e.g. land resources for national game parks, land under forest areas, land under small and large scale irrigation schemes, etc.

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(c) To assess all relevant crops, e.g. non-food crops such a s coffee, tea, etc.;

this entails development ^-of physical crop production models for these crops.

(d) To formulate criterion of crop choice based on district as well as national considerations, e.g. self-sufficiency levels and export possibilities, inputs availability, soil conservation measures. etc.

The usefulness and relevance of detailed country studies may be illustrated by the following type of issues that can be analyzed:

RpdaEion

a Identification and assessment of critical and potential areas to estimate needs of human migration and/or food transfers within and across administrative areas with the aim of improving self-sufficiency and equities (income and land distribution).

Chanelling of population planning programs to specific target areas.

R o h r c t i o n

What are the best crops t o produce (ecological and economic comparative advantage) and what consumption and trade policies to be pursued (e.g. if wheat is ecologically unsuitable and sorghum is suitable then policies for sorghum consumption).

What are the problems of and a t what rate and how should the rainfed and irrigated land resources be developed in the future t o reach higher potentials in specific locations within t h e country.

What are the future farming technologies and soil conservation measures required and feasible for achieving alternative levels of self-sufficiency and export targets of various crops.

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Information on potentially cultivatable land by extent, quality a n d location, a n d data on present land use provides a framework for t h e scope/timeframe for land-extensive agricultural development.

Seeds a n d crop varieties, fertilizers (organic and inorganic), pesticides a n d power (human, animal, t r a c t o r ) and land conservation measures: p r e s e n t use a n d f u t u r e requirements t o design appropriate agricultural development policies t o e n s u r e t h e availability and use of improved farming technologies.

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2. O l m l w n m AEZ-METHODOLOGY

The population supporting capacity of land resources depends on t h e productivity of land. The potential productivity of land resources on a sustainable basis in t u r n depends on a large number of interacting factors, namely:

-

climatic conditions such as temperature, sunshine, moisture, etc.

-

characteristics of t h e land and soil

-

kinds of crops grown

-

farming practices (input levels and soil conservation measures)

The concepts and principles of the

m Z

methodology for the assessment of food production and population supporting potentials a r e scale neutral; t h i s study applied t h e methodology to countries in t h e five regions of t h e developing world on t h e basis of t h e 1.5 million scale land resources inventory. For detailed country planning studies more detailed and refined land resources inventories a r e necessary.

Figs. 1 a n d 2 show the methodological framework of the

AEZ

study and t h e detailed country study respectively. The numbers in Fig. 1 relate t o t h e main steps in t h e application of the methodology and a r e described below. A numerical example of t h e application of the

m Z

methodology for a particular agro- ecological cell is given in Annex 1. Various aspects of the methodology and data reflnements for detailed country studies a r e dealt with in more detail later.

2.1. Main Steps in the AEZ-Methodology

The numbers in brackets relate t o t h e numbers in Fig.1.

(a) Land r e s o u r c e s : fw e a c h c o u n t r y

STEP

1: Computerize Soil Map. Using this as a base also computerize Climate a n d

LGP

Maps (1)

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Fig.1 FAO/IIASA/UNFPA LAND RESOURCES FOR POPULATIONS OF THE FUTURE:

METHODOLOGICAL FRAMEWORK

' Basic Land Invmtoria, by Country

3

- -

2 Non-Agricultural

L A

Fv Land Use

1975 and 2000 _{1975 m d}2000

T

Irrigation Production Inventory of Land Available 4

--

_{1976 and}₂₀₀₀ for Rainfed Cultivation Farming Technology Level 5

I

6 Major Climate Characteristics Crop Temp.

Requirements

=

7 CropClimate

Suitability

I

_I

1

Multiple Cropping Increments

Crop AgroClimatic Productivity

b from Grassland and

Fallowland

11 Fallow Period

-

Seed Requirement

Requirements b ₁₅ arvest and Post-

-

---

• 16

r

Yochno~ogy Matrix

7

I Current Input I Requirement I

-

Land Agronomic

/

)

Productivjty Potential

I

¹⁸

L.

r

Crop CelorieProtein

1

C

I

Conversion Factors

19 AggrcgateResulaofall Cells in each LGP Zone

Requirement Constraint

0 ' )

I

22 Maximum Calorie~Protcin CalorieProtein Production by LGP Zone Requirements

I, by Country

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Fig. 2 AGRICULTURAL DEVELOPMENT PLANNING

-

AGRO-ECOLOGICAL ZONE METHODOLOGICAL FRAMEWORK FOR COUNTRY STUDIES

,

- Country land Resourcas Inventory; Climate and Soil by Agro-ecologiul Cells and Administrative Areas

2 . Land Requirements

-

lnigeted Production I

for Rainfed Cultivation

6

Multiple Cropping Increments

t

Crop Yields by Lengho of Growing Periods Crop A g L l i m a r

Produnivity lo Soil, phase. s l o p

@ Livestock Production

Texture Limitations l2 from Grassland

11

b

r---

If I n p u s Required: I

r

^Seed,Fertilizer, I Pesticides, Power I

Conservation Measurn

Land Productivity 15

l6 Production Ponntial of H a m and Pan Alternative Crops in Each H~NW. Larras Agroccological Cell in the

Rainfed lnvcntory

- -

Livestock Produnion from

-v

,,

Crop Residues and Crop ByProductr

4 Fish Produnion

Cropping P i c b m Food and Agriculture Planning

Administrative Areas/Cwntry Production-hlix t o Simultamornily

M w t SelfSufficieney T argets Maximize Revenue Generated Maximize Export Revenue

within

Agricultural Produnion Pasibilitia

I

end Input Availability Constraints ^I Prices

f

I

Results Aggregetion

1

Individual LGPs in Adminimative Areas Adminisnative Areas

Country

Population -Human -Livestock

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to obtain

BASIC LAND RESOURCES INVENTORY

-

BY COUNTRY

STEPS 2-4: Deduct non-agricultural and requirements (2) and irrigated land (3) areas by location

to obtain

INVENTORY (4) OF LAND AVMLABLE FOR RAINFED PRODUC- TION (by agro-ecological cell)

(b) F b m i n g Technology and h p t LRveLs

STEP 5:Choose low, intermediate or high level (5)

( c ) Physical crop production model: for each of the crops of the assessment STEP 6-7: Apply crop-climate rules (6)

t o obtain

CROP-CLIMATE SUITABILITY (7) STEP 0-9: Apply crop yield - LGP rules ( 8 )

t o obtain

CROP AGRO-CLIMATIC PRODUCTIVITY (9) STEP 10: Apply crop-soil rules (10)

to obtain

ANTICIPATED CROP YIELD (d) 2ust ainability of pro d w tion

STEP 11: Apply fallow period rules (1 1) to obtain

(ANNUAL) ANTICIPATED CROP YIELD

STEP 12: Apply soil loss-productivity loss model (12) to obtain

EXPECTED CROP YIELD

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(e) f i t e n t i a l production and input r e q u i r e m e n t s

STEP 13-15: Livestock (calorie and protein) production from grassland and fallow land (13)

Apply seed (14) and waste (15) coefficients to obtain

CROP PRODUCTION: LAND AGRONOMIC PRO- DUCTIVITY POTENTIAL (17)

SI'F,P 16: Use FA0 global technology matrix (16) for each crop

to estimate

FERTILIZERS (N, P, and K), PESTICIDES, SEED (TRADITIONAL AND IMPROVED) AND POWER REQUIREMENTS

STEP 18-19: Apply crop calorie-protein conversion factors (18) and from t h e results of all crops in t h e assessment choose t h e crop giving maximum calories (19)

to obtain

CALORIE AND PROTEIN PRODUCTION IN EACH AGRO- ECOLOGICAL CELL

STEP 19: Aggregate these results for all cells in LGP zone and add livestock calories and protein and any irrigated production to obtain

TOTAL CALORIE AND PROTEIN PRODUCTION, CROP-MIX AND INPUTS* REQUIRED IN EACH LGP ZONE

.Current production inpute (fertilizers by N, P, K type, power and seed).

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STEP 20-21: Check calorie-protein ratio for each LGP S country calorie-protein ratio, i.e. minimum protein availability constraint.

If not acceptable t h e n repeat STEP 10 for some cells in t h e LGP zone until minimum protein requirement is met.

In t h e case of LOW and INTERMEDIATE inputs apply present crop-mix constraint (20)

to obtain

MAXIMUM CALORIE/PROTEIN PRODUCTION IN EACH LGP ZONE

(jl PopuLation supporting capacity

STEP 22-24: Maximum calorie/protein production by LGP zone

Apply country calorie requirement (23) t o estimate potential population ir, each LGP zone and compare with 1975 LGP zone population

t o identify

CRITICAL AND SURPLUS LGP ZONES IN EACH COUNTRY

Aggregate LGP zone results for each country t o estimate country potential population

to obtain

COUNTRY LEVEL RESULTS

For t h e year 2000 runs**, aggregate all LGP results in each country

t o obtain

COUNTRY LEVEL RESULTS

*The difference in the year 1875 and year 2000 arises ?om irrigated area/production and non-agricultural land requirement; for the year 2000 only country level results are present- ed aince the projected population by LGP zones are not available.

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3. ~ O D O L O G Y

AND

DATA FDR DETAILED COUNTRY SI'UDIES In this section various components of t h e overall methodology as depicted in F'ig.1 will be considered in detail. The description of t h e Phase 1 AEZ methodology and data will be followed by assessment of t h e refinements and extensions necessary for Phase 2 detailed country agricultural planning case studies (fig.2).

3.1. Climate and Soil Resources for Agriculture Production

The primary aim of creating a climate and soil inventory is to predict crop productivity. Hence t h e basic inventory must be compiled in a form t h a t will permit t h e interpretation of t h e climate and soil resources in terms of t h e i r suitability for production of crops under consideration. The appropriate climate adaptability and soil suitability attributes of t h e crops therefore will dictate what parameters a r e to be explicitly taken into account in t h e compilation of t h e inventory.

3.2. Soil and CLimate Inventory

In t h e AElZ study, t h e FAO/UNESCO Soil Map of t h e world (FAO, 1971-81 and Dudal and Batisse, 1978) was used as t h e physical resource base map of t h e land inventory for each country. For each unit of land (a grid overlay of 2mm x 2mm on t h e Soil Map, i.e. 10,000 h a land units), t h e Soil Map provides data on soil type, phase, texture and slope (Table 1) by location in each country.

A climate inventory, in terms of prevailing temperature regimes and length of growing period zones, was overlaid on t h e soil map. This climatic inventory was developed on t h e basis of available meteorological data (rainfall, maximum and minimum temperatures, vapour pressure, wind speed and sunshine duration (FAO, 1976b)). For t h e temperature regimes, fourteen major climates were delineated. Table 2. The concept of length of growing period zones, characterizing

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-

¹⁶

-

Table 1: SOIL CLASSIFICATION - AEZ STUDY

the time (number of days) available when moisture conditions permit growth, F A 0 UNESCO SOlL MAP: 106 DIFFERENT SOlL UNITS: 1 : 5 MILLION SCALE

was developed. A moisture supply from rainfall of half or more than half potential evapotranspiration (PET) was considered suitable t o permit crop growth. A

26 MAJOR SOIL UNITS

3 TEXTURE CLASSES 3 SLOPE CLASSES

12 PHASES

growing period with a humid period (i.e. a period with an excess of precipitation

FLWISOLS ARENOSOLS SOLONCHAKS KASTANOZEMS

GLEYSOLS RENDZINAS SOLONETZ CHERNOZEMS

REGOSOLS RANKERS YERMOSOLS PHAEZEMS

LITHOSOLS ANDOSOLS XEROSOLS GREYZEMS

CAMBISOLS VERTISOLS ACRISOLS HISTOSOLS

LWISOLS PODZOLUVISOLS NITOSOLS

PODZOLS FERRALSOLS

PLANOSOLS

COARSE, MEDIUM AND HEAVY TEXTURE 0 - 8 s . 8 - 3 0 % . >30%

STONY, LITHIC, PETRIC, PETROCALCIC, PETROGYPSIC, PETROFERRIC, PHREATIC, FRAGIPAN, DURIPAN, SALINE, SODIC, CERRADO

over potential evapotranspiration) is inventorized a s a normal (N) growing EXAMPLE: KENYA COUNTRY STUDY: 380 SOlL MAPPING UNITS,

CLASSIFICATION ACCORDING F A 0 1 UNESCO LEGEND, SCALE 1 : 1 MILLION 6 SLOPE CLASSES: < 2%, 2-5%, 5-8%, 8-16%, 16-30%, > 30%

period. A growing period with no humid period is inventorized as an intermediate (I) growing period. Altogether twenty-one growing period zones, Table 3.

were delineated by isolines of growing period with values of 0, 75, 90, 120, 180, 210, 240, 270, 300, 330, 365- a n d 365+ days..

'365 year round growing period 985' year round humid growing period

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-

^17-

Table 2: CHARACTERISTICS OF MAJOR CLIMATES: AEZ STUDY

Example: Kenya Country Data: Nine Major Climates defined by the following ternpertlire regimes

> 25.0,22.5-25.0,20.0-22.5,17.5-20.0,15.0-17.5,

12.5-1 5.0,.10.0-12.5,S.O-10.0,< 5.0 (Daily Mean Temperature

OC)

L

.

J

24hr, Mean Temperature (C)

Regime during the Growing Period More than 20 15-20

5-1 5 Less than 5 More than 20

15-20

More than 20

15-20 5-1 5

Less than 5

5-20

Less than 5 5-20 Less than 5

L

MAJOR CLIMATE TROPICS

All months with monthly mean temperatures, corrected to sea level, above 18°C

SUB-TROP!CS

One or more months with monthly mean temperatures, corrected to sea levd, below 18°C but all months above 5°C

TEMPERATE

One or more months with monthly mean temperatures, corrected to sea level,

below 5°C

Maior Climates during

No 1 2 3 4 5

6 7

8

9

10

11 12 13 14

Growing Period Descriptive Name Warm tropics

Moderately cool tropics Cool tropics

Cold tropics

Warm/moderately cool sub-tropics

(summer rainfall) Warm moderately cool sub-tropics

(summer rainfall)

Warm sub-tropics

(summer rainfall)

Moderately cool

sub-tropics

(summer rainfall)

Cool sub-tropics

(summer rainfall)

Cold sub-tropics

(summer rainfall)

Cool sub-tropics

(winter: rainfall)

Cold sub-tropics

(winter rainfall)

Cool temperate

Cold temperate

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Table 3: LENGTH OF GROWING PERIOD ZONES IN NUMBER OF DAYS WHEN WATER IS AVAILABLE FOR PLANT GROMH

(N) NORMAL LENGH LENGTH OF GROWING PERIOD (I) INTERMEDIATE LENGTH OF GROWING PERIOD 36% IS CONTINOUSLY HUMID

365- IS NOT CONTINOUSLY HUMID AEZ STUDY

LGP ZONES(DAYS)

36% (N)

365- (N

330-364 (N) 300-329 (N) 270-299 (N) 240-269 (N) 210-239 (N) 180-209 (N) 150-179 (N) 120-149 (N) 90-119 (N) 75- 89 (N) 1- 74 (N) 0 DRY' 1- 74 (I) 75-89 (I) 90-119 (I) 120-149 (1) 150-179 (1) 180-209 (1)

0 COLD

1,2,3,4 RESPEC'TIVLY REPRESENT NUMBER OF LENGTH OF GROWING PERIODS PER YEAR AS MAPPED IN KENYA CLIMATE INVENTORY

EXAMPLE*: KENYA COUNTRY DATA LGP ZONES(DAYS) PATTERN*

MAPPING UNIT

36% 1

365- H-1

300-364 1-H

300-329 1 -H-2 270-299 1-2- H 240- 269 1-2 21 0-239 1-2-3 180-209 1-3-2 150-1 79 1 -2-D 120-1 49 1 -D-2

90-119 1-D

60- 89 2

30- 59 2-1 1- 29 2-1 -H 0 DRY 2-1 -3

2-3 2-3-1 2-3-4 2-1 -D 3-2 3-2-1 3-2-4 D

*In Kenya Country Study 15 LGPs Zones and 22 pattern mapping units are recognized.

For example the pattern coded 2-1 -3 represents the number of growing periods per year in order of frequency of occurance.

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The above soil a n d climate inventory for each country was computerized in t h e form of agro-ecological cells; each cell was specified by major climate, length of growing period zone, soil type, soil phase, soil texture, soil slope and extent of land in t h e cell. This information forms t h e basis of t h e Basic Land Resources Inventory available for e a c h country in the AEZ study.

3.2.1. Country Refinements and Extension

Depending on t h e country level soil and climate d a t a available, t h e basic land inventory can be refined or replaced by a detailed inventory. Fig.3 shows t h e data relevant for compiling s u c h an inventory. At t h e country level i t is important to develop t h e basic land inventory by s t a t e , district and/or province, i.e. administrative areas; t h e s e localities a r e often relevant for planning.

Examples of t h e type of c o u n t r y refinements a r e shown in Tables 1-3 for soils, climates and length of growing period zones respectively. The refinements of t h e s ~ i l and climate resources inventory for a particular country will depend on t h e information available. For countries with little or n o information t h e FA0 Phase 1 land resources inventory provides a starting point.

3.3. land Use

Not all t h e inventorized land in t h e inventory is available for rainfed agricultural production. Land requirements for irrigated use a n d non-agricultural use need to be considered.

In the AEZ study land u n d e r irrigation (in year 1975 and projected t o be in year 2000) was identified by e x t e n t and location on t h e soil map for each coun- t r y (Wood, 1980). The basic country level information was obtained from FAO's AT2000 study and t h e irrigated a r e a s were located on t h e map according to country information and/or expert knowledge. Once located, t h e irrigated acreages were deducted from t h e relevant agro-ecological cells. It should be

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Fk. 3 COMPILATION OF CLIMATE AND SOlL INVENTORY-COUNTRY STUDY

CLIMATE DATA RAINFALL

METEOROLOGICAL STATIONS TEYPERATURE

PRESSURE LENGTH OF GROWING HISTORICAL RECORDS

WIND SPEED _(I.#. 10 DAY INTERVAL) SUNSHINE

TRANSCRIBE SOlL TYPE/ VARIETY

MAPPING UNITS) SOIL PHASE

SOlL INVENTORY

*

SOIL TEXTURE PHYSIOGRAPHIC LAND TYPE

GEOLOGY SOIL SLOP€

DOMINANT SOlL

LAND RESOURCE INVENTORY

I

COMPRISING AGROECOLIGICAL CELLS

DEFINED BY - EXTENT OF LAND BY SOIL TYPE

I

PHASE TEXTURE SLOPE

I

WITHIN MAJOR CLIMATE

WITHIN LENGTH OF GROWING PERIOD AND PATTERNS

1

noted t h a t irrigated production is included in t h e assessment of population supporting potential (Fig. 1, step 3).

For t h e non-agriculture land use (Hyde, 1980). lack of country level data resulted in t h e adoption of an assumption t h a t non-agricultural land use is related t o t h e population distribution within t h e country. Population census d a t a for e a c h country was used to locate t h e population by length of growing period zones in each country. Within each LGP zone i t was assumed t h a t t h e non-agricultural l a n d use is equivalent to 0.05 ha per person. Accordingly, t h e e x t e n t of land in e a c h agro-ecological cell within a zone was reduced according t o t h e population density.

The above 'deductions' for irrigated and non-agricultural land use in t h e total land inventory for each country resulted in t h e quantification of t h e

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inventory of land available for rainfed cultivation.

3.3.1. Country Refinements and Extension

Country information, Kg. 4, by s t a t e , district and/or province should be used to quantify t h e extent and location of irrigated areas (present, planned a n d potential a r e a s in t h e future), non-agriculural land use, 'other' agricultural land use a n d forest land use on t h e country soil/climate map.

Non-agricultural land requirements will include a r e a s required for habitation (e.g. boundaries of towns, cities, etc.). industry, mining, recreation (e.g.

national parks and reserves), transport and infrainfrastructure, etc. Note t h a t due t o extensive distribution of t h e r u r a l population. an approximate allowance for habitation in terms of hectares per person will still be necessary. For the 'other' agriculture use, a r e a s under crops (which a r e not formally being considered i n t h e detailed country study) should be identified on t h e country soil map and appropriate land use 'allowance' be made. P r e s e n t and f u t u r e forest- designated areas, especially productive forest reserves for fuel wood a n d timber will need t o be located and explicitly considered.

A t t h e detailed country level study, an effort should be made to formally include all important crops; for any additional crops an appropriate a r e a 'allowance' will have t o be made, e.g. vegetables grown throughout t h e country t o some extent may be considered in this manner.

3.4. Land Resources Available for Rainfed Production

The land resources available for rainfed production a r e quantified from t h e basic land resources inventory after making appropriate deductions for the requirements of irrigated, non-agriculture, 'other' agriculture a n d forest land use. F'ig.4. A t this stage, for a particular country, the land resources inventory available for rainfed production comprises of t h e following hierarchy:

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Fig. 4 ESTIMATION OF RAINFED LAND RESOURCES: COUNTRY STUDY

IRRIGATED IRRIGATED AREAS

-

LAND USE AND

PRODUCTION

URBAN AREAS POPULATION

DISTRIBUTION BY ZONE LAND USE TRANSPORT AND

INFRASTRUCTURE

- -

5 5

AGRICULTURAL

GAME AREAS

- ^{5 s} *,

MINING AREAS ² Z C

>

E

a d h

INDUSTRIAL AREAS

' _n

ADDITIONAL* FOOD DTHER'

AGRICULTURAL AND NON-FOOD

CROPS LAND USE

FOREST AREAS

LAND USE ⁷

+Crops not fwmrlly considcnd in the study

within each major climate there are a number of length of growing period zones

within each LGP zone there are a number of agro-ecological cells

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each cell is a basic land u n i t specified by extent of land in the cell, soil type. soil phase, soil t e x t u r e and soil slope.

The next s t e p in t h e methodoloy is to choose a particular farming technology a n d input level a n d then t o assess t h e production potential on a crop- by-crop basis in each agro-ecological cell.

3.5. Crops of the Study

Fifteen food crops, Table 4, were chosen on t h e basis of t h e most impor- t a n t crops (in t e r m s of t h e acreage planted) in t h e world a n d in some c a s e s in t h e developing world. The l a t t e r applied t o banana/plantain a n d oil palm. Two of t h e crops, namely rice and wheat were considered according t o type, namely upland rice, paddy rice, winter wheat and spring wheat. Note t h a t grassland is considered as a crop for t h e rangeland production of livestock

Table 4: CROPS CONSIDERED IN AEZ STUDY

CROPS OF THE AEZ STUDY SPRINGWHEAT, WINTER WHEAT, PADDY RICE, UPLAND RICE, MAIZE, WINTER BARLEY,SORGHUM, PEARL MILLET,

WHITE POTATO, SWEET POTATO, CASSAVA, PHASELOUS BEANS, SOYABEANS, GROUNDNUT, SUGAR CANE, BANANAlPLANTAIN, OIL PALM, G RASSLANDI LIVESTOCK

EXAMPLE: KENYA COFFEE ARABICA, COFFEE ROBUSTA, SISAL, PINEAPPLE COUNTRY STUDY COTTON, TEA, PYRETHRUM, CASTOR BEAN, SESAME,

ADDITIONAL CROPS SUNFLOWER, TOBACCO, FUEL WOOD AND TIMBER,

CONSIDERED CASHEW

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3.5.1. Country Level Choice of Crops

For a detailed country study, t h e most important crops including food and non-food crops will have t o be considered. Note t h a t for all crops formally considered in t h e study, it will be necessary to develop appropriate crop production models as described in Section 3.7. If i t i s not feasible t o do t h i s for some of the crops and/or for o t h e r minor crops, d a t a on present a n d f u t u r e acreage and production by location within t h e country will be required t o make an allowance for t h i s l a n d requirement. Such information may be g e n e r a t e d from district surveys/plans. Landsat imagery etc. Examples of relevant additional crops for a country study a r e shown in Table 4.

Another important aspect t o be considered is i n relation t o c r o p m i x and cropping patterns. Generally crops a r e grown in rotation a n d mixes r a t h e r than individual crops. In t h e application of t h e methodology especially a t sub- national level s u c h aspects will need t o be incorporated through explicit consideration in t h e c r o p production models or as a constraint in crop choice.

3.6. Farming Technology and Input Levels

Three separate levels of input, namely Low. Intermediate and High a r e defined in t h e study t o represent subsistence, subsistence/commercial and commercial farming systems respectively. Table 5. Corresponding t o t h e t h r e e i n p u t levels and each crop of t h e study, yield tables according t o

LGP

zones have been developed on t h e basis of physical crop production models.

The crop yield-input relationships from t h e Global Technology Matrix (GTM) of t h e AT2000 study (FAO, 1981), Table 6, is used t o quantify i n p u t requirements for seed

--

traditional a n d improved. fertilizer N-P-K, pesticides and power

--

human, animal and mechanical. The GTM for a particular crop gives t h e yield- i n p u t relation a t four discrete yield levels; for yield in between t h e s e levels a

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Table 5: ATTRIBUTES OF INPUT LEVELS

linear interpolation procedure is used t o estimate the input requirements.

3.6.1. Country Level Refinement and Ektension

For a country level study, relevant farming technologies a n d local crop yield-input response relationships have to be considered. For example, t h e high input yield level for a particular crop may entail a mixture of human. animal and mechanical power r a t h e r t h a n only mechanical power a s considered in t h e Phase 1 study. The issue of management (e.g. timeliness and efficiency of opra- tions such as planting, weeding, etc.) has a significant effect on t h e yield level

ATTRIBUTE

RodKcim Svnmu

T d w

E W 0 V - d

P- R.rawol

L l b a u I n m * n

C40it.r I-

M d m O l h m i o n

I n f m w c n m R . p u i n m m

L l n d H o M n p C w m l r p ~ Ramlid.

LOW INPUT LEVEL

Rainhd CulthRion d R.m* G r o m Mixtun of cmp

L o a l Cultbus. No F w t l l h w a Ck.m*.l Pnt. D h . r m d W a d C o n a d . R n t ( F m i k r l P ~ i a b . No Lon)-T.rm SOU

c- run.

M dL l b a u With Hmd Tods

H W , lndudhrl Uncmd F m l b tlbau L a

S l l b j l a r p r h a b c t b a

M d m A c a r # H W not

m=aaw. ¹^-

A d . k q - F n F m d J d T n d i t k r J

H- L.bar

INTERMEDIATE INPUT LEVEL

R h f d CuMntion w i t h P m C h a w m Optimum Mi- d cmp

Impad C u k m n r Am-.

Limiad Fercillzw AppUcrrPn.

Simpl. Exbraion P r k - inck ding S o m C h . m i P.n, D h . r rd wndcanvd. S o m R a (F.lkr) Pwiod. S o m S i Lon)-Tam C m m c i m MmNm M d L . b o r r r l t k H r d T m l r md/ a A n i d T n c r k n with l r n p 0 n d I W m - a H W . Mudha P m C m d hmb L l b a u Irmnnd*e with C n d k a

A- T m

-Pmduc(hr,m C a r n n r r d . 1 S I d ~ bnr M d m A a r i b i W N- f a v y r l t k A a a r m Dmmmmlb P k b m d h w b a a

JocnanrCadlb*d Sad T n d k k r r U lrnpad H u m m L . b a r l A n k d P a r F w t l l h r N-P-K

P.rokibr

HIGH INPUT LEVEL

Rminhd C u h d o m of Opti- M i x n m d C m p

H* Y W d i CuWwn. OMmum F e r t l l l a A p p l i t i o n . Chomial Pnt. D k u md W n d Camd.

Mlni- R m ( F J k r ) P e w . c-conrmtbn~aua.

C o m p t n M . d r J u t k r , I ~ H r r a t * l l

L a . FmOy L.bou C m d if u d

H W

Cornnrrblhodrc(kn

M u b t A c O d b j J W E D l m W . HWL...(dA*S.rrior

mdApplkbkndR.F- C a n d i b l J 1 r n p o r d S - d M.dwn*.l P a r F d 1 h . r N-P-K Poniddm