THE IMPACT OF HIGH YIELDING VARIETIES OF WHEAT ON ECONOMIC PERFORMANCE, NUTRIENT

1
THE IMPACT OF HIGH YIELDING VARIETIES OF WHEAT ON
ECONOMIC PERFORMANCE, NUTRIENT FLOWS AND SOIL
EROSION LEVELS IN THE ETHIOPIAN HIGHLANDS THE
CASE OF GINCHI WATERSHED
BEN .N. OKUMU (CORNELL UNIVERSITY)
2
STUDY OBJECTIVES

• Develop, a Bio-economic Model and examine the
  individual and the combined impact of alternative
  technological, institutional and policy
  interventions
• Test efficacy of watershed as an analytical
  framework for assessing natural resource
  management.

3
OUTLINE OF PRESENTATION

• STUDY GOAL AND OBJECTIVES
• MODELING WATERSHED RESOURCES
• MODEL STRUCTURE SPECIFICATION
• 1995 BASELINE MODEL
• STATIC versus DYNAMIC MODEL RESULTS
• SINGLE versus MULTIPLE INTERVENTION RESULTS
• SOIL CONSERVATION versus HUMAN NUTRITION
• CONCLUSIONS

4
MODELING WATERSHED RESOURCES

• Dynamism- nature is a set of processes rather
  than a collection of objects
• Interlinkages in processes call for landscape
  rather than household level analysis
• Hierarchy- processes relate at different scales
  and differ in terms of temporal and spatial
  scales on which they are organized
• Differential fragility- agroecosystems vary in
  the extent to which they can absorb and
  equilibrate human caused disruptions in their
  processes

5
LOCATION OF GINCHI WATERSHED IN ETHIOPIA
6
Model Constraints (USLE)
7
STUDY GOAL

• Contribute towards an improved understanding of
  optimal watershed management and display the
  interrelationships between- technology, policy,
  soil erosion, cash income and nutrition
  (sustainability).

8
STRUCTURE OF THE GINCHI WATERSHED BIO-ECONOMIC
MODEL
LANDTYPE A
LANDTYPE B
LANDTYPE C
LANDTYPE D
NATURAL RESOURCE CHARACTERISTICS
PRODUCTION ACTIVITIES
MODIFIED USLE MODEL
Policy characteristics
Watershed agg. farm Characteristics
Dynamic Programming Model
Economic Results (income, output,nutrition)
Environmental Results (erosion, nutrient
balances)
RESULTS
9
OBJECTIVE FUNCTION
10
Contd
11
Soil nutrient balances
12
Human Nutrition
13
Baseline model

• Actual Situation
• Diversified land use pattern, crop rotation and
  modest fertilizer application are the main risk
  management and land conservation activities
• Soil loss is 31 t/ha/annum or 25 lower than the
  national average
• Production is for subsistence with some market
  purchases

14
Dynamic model results

• Scenario 1 Impact of short and long time
  horizon
• Estimated 1996 land A pattern close to actual
  1995 situation
• Soil loss at end of ST is 20 higher than at end
  of LT but income is only 2.6 higher
• Change cropping pattern and practice crop
  rotation
• Teff buying rises by 52 in first 7 years then
  falls by 70 in next 5years emphasizing
  importance of markets in sustainable management
  of the watershed.

15
Limited intervention

• 50 rise in cash incomes
• 34 increase in soil erosion
• Soil nutrient balances per ha at-
• -58kgs nitrogen
• -32kgs phosphorous
• -114kgs potassium
• Purchase of staples necessary
• Minimum daily calorie intake per AE 1500 cals

16
Multiple intervention results

• Ten fold rise in incomes
• 20 reduction in soil erosion
• Nutrient balances per ha are-
• -25kgs Nitrogen
• -14kgs Phosphorous
• -68kgs potassium
• No purchases of staples necessary
• Minimum daily calorie intake per AE 2000 Cals.

17
Human nutrition versus environment
10000
Erosion (tons) before intervention
with 1500 calories/AE
8000
Erosion (tons) after intervention
with 2000 calories/AE
Value
Erosion (tons) after intervention
6000
with 1500 calories/AE
4000
Wheat fertilizer (kg)
Teff fertilizer (kg)
2000
Maize fertilizer (kg)
0
12
11
10
9
8
7
6
5
4
3
2
1
Years (1995-2006)
18
Conclusions

• Tradeoff betwn food sufficiency vs conservation
• external intervention.
• Secure land tenure policy required
• Credit needed to enable use of new technologies
• Commercial policy to facilitate conservation
  through crop rotations
• Transdisciplinary research required to address
  social biophysical issues.

19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
(No Transcript)
26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
(No Transcript)
30
(No Transcript)