impact of changes in land use and land cover on feed resources in the ethiopian highlands
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Impact of changes in land use and land cover on feed resources in the
Ethiopian highlands
Kahsay Berhe1, Zerihun Woldu2, Don Peden1, Dirk Hoekstra1 and Alemayehu Mammo3
1International Livestock Research Institute (ILRI), P.O. Box 5689, Addis Ababa, Ethiopia 2Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
3DC Office of planning, Washington DC 2009, USA
Introduction
Livestock are sources of food, draft power, cash income, fertilizer and energy among others. Ethiopia owns a large
number of livestock (45,930,163 TLU) (FAO 2010), the highest in Africa. The main sources of livestock feed in the
Ethiopian highlands are crop residues and natural pasture. The contribution of livestock is limited, because of poor
availability and quality of feed resources, among others.
The study area
The study site falls within 38051 43.63 to 39004’ 58.59 E and 8046 16.20 to 8059 16.38 N, located on the
western margin of the great East African Rift Valley in the Oromia region of Ethiopia (Fig. 1). Ten peasant associations
surrounding Yerer Mountain with a total population of 35,940 persons in 2000 and an area of 28,741 ha were selected
for the study.
Figure 1. The study area
Objective
The objectives of the study were to describe the land use and land cover (LULC) changes over three decades and
assess implications to livestock feed resources and recommend appropriate interventions.
Materials and methods
LULC analysis for the study area • District maps (1:50,000 scale) to delineate study area,
• 1971/72: Seventeen black and white aerial photos,
• 2000: Landsat ETM+ satellite image of February 2000,
• Digital image processing and visual interpretation of satellite images and aerial photos
Feed resources per ha from various LULC categories • Cultivated land: Survey from 132 households (hh)
• Other LULC types: WBISPP, 2001
Livestock and hh population • 1971/72: Topographic map to determine number of hh and CSO (1974) data to determine human and livestock
population
• 2000: Secondary data
Animal feed requirement • Livestock daily minimum feed DM requirement (Berhanu et al. 2004)
All the above resources were used to compare available feed vs needs of the various livestock types for both periods.
Results and discussion
LULC change
The 1971/72 land cover analysis (Fig. 2) showed that majority of the study area was under grasslands accounting for
18,784 (65.4%), while it was 9,396 ha (32.7%) in 2000 (Fig. 3). Cultivated land on the other hand increased from 7186
(25%) in 1971/72 to 16,204 ha (56.4%) in 2000. In 1971/72 majority of the shrublands were covered with Juniperus
procera and Acacia albida trees, while the area under these trees has dramatically decreased in 2000.
Figure 2. Land Use and Land Cover: 1971/72
Figure 3. Land Use and Land Cover: 2000
Much of the change occurred on cultivated land (Fig. 4). The increase in cultivated land was 125%, which was mainly
at the expense of the grasslands. Out of the total cultivated land in 1971/72, 80% remained under the same land cover
while 1281 ha (17.8%) was converted to grasslands in 2000. The reason for the conversion to grasslands could
indicate that the land is no more suitable for agriculture. The increase of cultivated land from 7,186 in 1971/72 to
16,204 in 2000 is population driven, i.e. number of households increased from 2,064 to 5,518 while total population
increased from 9,288 to 35,940 over the study period, respectively.
Figure 4. Land use and land cover dynamics 1971/72 and 2000
Net
shrubland
+117
369 ha
Net
grassland
- 9388
Net
cultivated
+ 9018
Net wet &
water body
+253
+10453 ha
-1435 ha
+1325 ha
-1208 ha
+331 ha
-78 ha
89 ha
266 ha
50 ha
65 ha 1236 ha
839 ha 28 ha
+2148 ha
-11536 ha
10,034 ha
1281 ha
Feed resources The household survey indicated that feed is sufficiently available during October to January, severely in short supply
during May to September, while the remaining months are intermediate. From among the cultivated crops, teff and
wheat were the major sources of crop residue, contributing to about 82% of the total residue (Table 1). Based on the
procedures for estimating crop residues from cultivated areas, a mean value of 1.52 t/ha DM was obtained (Table 2).
According to WBISPP (2001) 0.36 t/ha DM was also available as crop aftermath. Both figures were used for
multiplying the cultivated area to obtain total amount of crop residue in the study area. Based on WBSIPP (2001)
procedure, 1.45 and 0.83 t/ha was obtained from the other LULC types for 1971 and 2000, respectively (Table 2) .
Table 3. Daily and annual DM feed for MEm plus 20% production requirement for working animals in the study area
* Kahsay (2004) ** Based on Table 1, total crop residue (air dried)/total area multiplied by 90% to convert to DM yield/ha ***Air dried crop aftermaths at 0.4 t/ha/yr (WBISPP, 2001), but data multiplied by 90% to convert it to DM
****As per procedures by WBISPP (2001)
In the past decade, several research and development organizations (amongst others the Improving Productivity and
Market Success (IPMS) Project) have worked on the introduction of improved feed technologies to boost the
development of livestock commodity value chains. These technologies had important impact on feed resource
availability in the study area, like the introduction of newly released teff varieties which reportedly yield about 3 and 5 t
of grain and crop residues, respectively. Similarly, improved management of grazing areas by regulating livestock
access and introduction of cut and carry in other IPMS districts showed biomass yields of up to 10 t. Similarly, to
reduce the need for draft power, the project also introduced conservation tillage.
Livestock type Daily DM
requirement
(kg/head/d)*
Total number of livestock Total annual DM feed requirement (t)****
1971** 2000*** 1971 2000
Cattle (local) 4.33 11737 31462 18549.7 49724.1
Sheep 0.625 3349 8153 764.0 1859.9
Goats 0.625 4958 9091 1131.0 2073.9
Donkeys 3.00 2375 8164 2600.6 8939.6
Horses 4.20 138 633 211.6 970.4
Mules 4.20 192 231 294.3 354.1
Total 23551.2 63922.0
*Berhanu et al. (2004). **Computed based on CSO (1974). ***Obtained from four Offices of Agriculture and Rural Development (2003). **** Values obtained by multiplying daily DM requirement by total number of livestock and 365 days to get annual requirement.
LULC type Multiplying factor DM
yield (t/ha/yr)
Area (ha)* DM production (t)
1971 2000 1971 2000
Cultivated land 1.52** + 0.36*** 7,186 16,204 13,510 (30.4%) 30,464 (75%)
All other land cover
categories
1.45**** (1971);
0.83**** (2000)
21,365 12,224 30,979 (69.6%) 10,146 (25%)
Total 28,551 28,428 44,489 (100%) 40,610 (100%)
Conclusion As is the case in most highlands in Ethiopia, human population growth was the major driving force behind the LULC
changes, which in turn influenced livestock number, feed type and availability in the study area. Farmers’ priorities are
to grow food crops rather than forages or fodder for livestock. Cultivated area increased substantially at the expense
of grasslands. As a result, there is greater reliance on crop residues and on-farm production of fodder to feed stock.
The failure of available feed sources to meet even the maintenance needs of existing livestock indicates that
production from livestock will remain low unless strategies are developed to match existing livestock population. While
this trend is alarming, recent research and development activities in many areas, including the study area, show that
feed from existing grasslands and crop residues could easily increase using cut and carry system and newly released
high yielding varieties, respectively. Such new developments should, however, be integrated and follow multifaceted
approaches for creating a resilient ecosystem, including working on improving the quality of crop residues and
developing intensive livestock management systems, among others.
Crop type Total area (ha)* Average grain
yield (t/ha)*
Total crop
production (t)
Conversion factor
(straw:grain ratio)**
Crop residue (t DM)***
Wheat 94.00 1.42 133.29 2.06 192.49
Teff 92.60 1.00 92.32 2.47 160.11
Chickpeas 34.50 1.05 36.23 1.31 33.22
Faba bean 11.20 1.10 12.30 1.42 12.25
Rough pea 6.70 0.92 6.18 1.54 6.64
Field pea 6.60 0.79 5.23 3.30 12.04
Barley 6.20 1.09 6.75 1.86 8.80
Lentils 1.10 0.55 0.61 1.56 0.66
Maize 1.80 0.78 1.40 2.04 2.00
Total 255.70 431.21
*Based on three years’ mean data (2001-2003) from household survey. **Obtained from various sources (Kahsay 2004). ***Assuming that 70% of the crop residue will be used as livestock feed.
Table 1. Estimated yearly dry matter (t/ha) obtainable from different crop residues for the sample farmers in 2000.
Corresponding author: k.berhe@cgiar.org
Table 2. Estimated yearly feed DM obtainable from different land cover types from the study area for 1971 and 2000
Feed utilization/balance Considering minimum daily maintenance and 20% production requirements for livestock in the study area, annual feed
needs were calculated to be 23,551 (1971) and 63,922 t DM (2000) (Table 3). As can be seen from the table, there is
a substantial increase in cattle population over the study period (Table 3) because of increase in the need for more
draft power due to expansion of cultivated land. Accordingly, available feed (Table 2) exceeded requirements (Table 3)
by about 21,000 t in 1971, but fell short by about 23,000 t in 2000. Feed requirements for 2000 increased by over
170% due to increased livestock numbers (Table 3). Therefore, feed resources in the study area only met about 64%
of the minimum annual energy required (plus additional 20% for production) by livestock. In the central highlands of
Ethiopia, other similar works also reported that farms produce only 60% of the feed needed by livestock. This analysis
further indicated that about 75% of the DM to come from crop residues (including crop aftermath) in 2000 which only
contributed about 30% in 1971. In earlier works, it was also reported that 71% of the feed supply for Ada’a district (part
of the study area) to originate from crop residues.
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