Competing uses, dynamics, and production and utilization constraints of crop residues in East Africa: Implications for conservation agriculture

1Kindu Mekonnen, 2Gedion Rachier, 3Dagnachew Lule, 4Mesfin Bahta, 1Diego Valbuena, 1Alan Duncan and 1Gerard Bruno

1International Livestock Research Institute (ILRI), P.O.Box 5689, Addis Ababa, Ethiopia. 2Kenya Agricultural Research Institute (KARI), P.O.Box 169, Kakamega, Kenya3Bako Agricultural Research Center (BARC), P.O.Box 03, Bako, Ethiopia4Sirinka Agricultural Research Center (SARC), P.O.Box 74, Woldia, Ethiopia

Contents of the presentation

Introduction

Objectives of the study

Research methodologies

Research findings and discussion

Crops and crop residues

Cropping technologies

Competing uses of crop residues

Trend analysis on the use of crop residues

Production constraints of crop residues

Utilization constraints of crop residues

Implications of the present CR utilization for CA

Conclusions

Introduction

Crop residue production in the world - 3.8 billion Mg – cereals (74%), legumes (8%), oil crops (3%), sugar crops (10%) and tubers (5%) (Lal, 2005).

CRs have off-site/ product functions (feed) and on-site/ service functions (SWC).

CRs off-site uses

CRs on-site uses

The use of CRs for CA is challenged in the east African countries due to:

Studies on competing uses and other aspects of CRs are key for managing the available resources, searching more options and initiating more detailed research.

poor capacity of smallholder farmers to purchase/access various inputs and services.

lack of availability of alternatives for various competing uses of CRs.

1) investigate diversified and competing uses of crop residues

Objectives

2) analyze past trends of uses of crop residues

3) identify production and utilization constraints for crop residues

3. Research methodologies

Three sites were identified in two east African countries (Ethiopia and Kenya).

Selected 8 villages in each of the three sites based on market and road access: Near-Near, Near-Far, Far-Near and Far-Far

Identified 10-20 farmers in each village to respond as a group during the final village survey.

Considered a total of 24 villages in the three sites.

Characteristics of the three sites

  Kobo Nekemte Kakamega

Altitude 1416-1634 1748-2418 1426-1719

Major soil types Vertisol Nitisol Acrisols, Ferralsols

Mean annual rainfall (mm) 768 1037 2009

Mean annual temp (oC) 30 29 28

Total village population 330-2250 196-391 400-5000

Total village HHs 66-450 35-70 80-1200

Total village land (ha) 77-910 74-164 200-900

Total cultivated land (ha) 66-280 61-149 160-810

Major crops sorghum, teff maize, teff maize, beans

TLU 141-1004 69-213 121-673

3. Research findings and discussion

3.1. Crops and crop residues

 Crop types Kobo Nekemte Kakamega cereals teff,

sorghum, maize

maize, teff, sorghum, finger millet, wheat, barley, oat

maize, finger millet, sorghum

legumes chickpeas faba beans, field peas, soya beans

common beans, climbing beans and soya beans

oil crops nd noug bambara nuts, ground nuts hort. crops vegetables

(onion)vegetables (beet root, potato, anchote)

vegetables (sweet potato), cassava, banana, tea, sugarcane

Sorghum- Kobo Teff- Nekemte Beans- Kakamega

 Crop residues Kobo Nekemte Kakamega cereals teff straw,

sorghum stover, maize stover

teff straw, maize stover, barley straw, wheat straw, finger millet straw

maize stover, maize cobs, finger millet straw

legumes chickpea haulms and husks

faba bean haulms and husks

common and climbing beans

oil crops nd nd groundnut haulms, hort. crops nd nd sugarcane tops, sweet

potato vines, banana stems and leaves, vegetable stalks

Sorghum stover Teff straw Maize stover

Area coverage of crops and hh growing them in the main rainy season at the three east African sites.

 Cropping systems

Land allocated (ha)

Area coverage (%)

HHs growing (%)

Kobo cereals 963 97 75 legumes 19 2 37 oil crops nd nd nd hort. crops 5 1 8 fallow np np np

Nekemte cereals 581 74 78 legumes 13 2 46 oil crops 54 7 59 hort. crops 24 3 85 fallow 107 14 71

Kakamega cereals 1238 31 53 legumes 859 22 89 oil crops nd nd nd hort. crops 1776 44 75

  fallow 133 3 nd

Note: nd-there is no data, and np- there is no practice

3.2. Cropping technologies

 Area (%) Kobo Nekemte Kakamega

tillage by tractor 6.43 (11.4) np 14.4 (17.7)

tillage by animal 99.5 (1.4) 100.0 (0.0) 63.8 (28.9)

new seed 2009 25.2 (36.5) 28.3 (32.0) 89.4 (4.2)

chemical fertilizer 1.8 (2.9) 72.8 (19.4) 78.8 (13.8)

manure application 9.3 (14.1) 22.3 (26.0) 54.4 (28.2)

hand weeding 100.0 (0.0) 97.9 (6.0) 97.8 (3.5)

herbicide application 34.1 (26.8) 51.1 (29.4) 2.8 (4.0)

pesticide application 25.3 (38.4) 39.5 (33.0) 4.1 (3.2)

thresher use np 4.0 (0.0) 1.0 (0.0)

chopper use for feed np np 2.3 (2.3)

Data represent means with standard deviations in parentheses. The number of villages (n) is 8 for each of the three east African sites.

3.3. Competing uses of crop residues

0

20

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60

80

100

120

Kobo Nekemte Kakamega

other uses

households fuel

stall feeding

sell from home and field

grazing by animals

left as mulch

Bars above the lines indicate increase in the last 10 years while bars below graphs indicate decreases.

3.4. Trend analysis on the use of crop residues

fuel

Bars above the lines indicate increase in the last 10 years while bars below graphs indicate decreases.

3.4. Trend analysis on the use of crop residues

3.5. Production constraints of crop residues

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25

30

Kobo Nekemte Kakamega

soil fertility decline

high inputs/low outputs price and inputs unavailability

lack of information/services

problem of weeds, pests and diseases

rainfall/drought problem

3.6. Utilization constraints of crop residues

About 60 % of the ruminant livestock in Kobo, 20 % in Nekemte and 25 % in Kakamega are dependent on CR.

The stem part of some plants is hard and highly lignified. As a result, animals prefer the finer parts and thus causing significant losses of the residues.

Lack of information and access about various CR processing methods are major bottlenecks for efficient utilization of CRs.

3.7. Implications of the present CR utilization for CA

The soil in crop fields suffers a lack of permanent cover due competing uses of CRs.

Perennial crops are less integrated into the crop fields to avoid competition for space.

29 % of CRs in Kakamega retained on the soil surface to enhance and maintain soil quality.

Nearly 100% of CRs in the Eth sites are removed from the crop fields and allocated for product functions.

Possible options to balance competing uses of CRs:

Implement integrated farming approaches – helps to save more CRs for covering the soil and improving its fertility.

Producing enough biomass- use of cropping technologies (irrigation, improved crop varieties) and intensive farming.

Introducing compatible and high value perennial crops in croplands so as to improve the year round soil cover.

Enhance the knowledge of farmers on the management and efficient use of CRs-capacity building schemes.

5. Conclusions

CRs are very useful crop by-products for smallholder farmers. Their use for animal feed surpassed the other competing uses in all the sites.

Soil/land related problems; weed, insect and pests; high input/low output prices; poor distribution of rainfall/drought; and lack of information/services are some of the constraints associated with low crop productivity and production of CRs.

Dealing with some of the crop and CRs production constraints to enhance overall crop productivity could provide more scope for the use of CRs for CA purposes.

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