Root production, soil organic matter, soil moisture, and sorghum yield in an alley-cropping system with Acacia saligna (Labill.) Wendl. and Gliricidia sepium (Jacq.) Walp. in the Hararghe Highlands, Eastern Ethiopia

A field experiment was conducted to study root production, soil organic matter, and moisture and sorghum yield in an alley-cropping system with Acacia saligna and Gliricidia sepium in the Hararghe highlands of Ethiopia. Tree hedgerows were planted on either side of a 4-m wide crop alley. Intra-row spacing between trees was 25, 50, and 100 cm. In October, 1994 and March, 1995 soil samples were taken at depths of 0-10 cm and 10-30 cm at 50 and 200 cm distance from the hedgerows using direct coring and mesh bags. Roots were separated from the soil by wet-sieving and root weight and root length density were determined. Measurements of soil organic carbon and total nitrogen to a depth of 0-60 cm were made. Field tensiometers were installed at 10, 30 and 60 cm depths. Soil water content was periodically monitored at similar depths. Sorghum grain yield, above-ground dry matter and height were determined. Acacia fine-root (≤2 mm) mass was significantly (p≤ 0.05) higher than for Gliricidia in the top 30 cm of soil. The presence of fine roots decreased by 55% and 40% for Acacia and Gliricidia, respectively, as the distance increased from 50 to 200 cm from hedgerows. Increase in tree root mass was accompanied by proportionally decreased crop root mass. Results of the March samples showed that the dry period is when trees allocate a higher proportion of carbon to the root system to stay competitive under the dry conditions. Leaf and twig dry matter of Acacia was significantly (p≤ 0.05) higher than for Gliricidia. Soil organic matter was lower by 20% and 10% in control and Gliricidia plots compared to Acacia plots. Soil moisture content and water potential measurements indicated that soil moisture was lower in Acacia plots than in the control and Gliricidia plots. Sorghum biomass, grain yield and height were significantly (p≤ 0.05) higher with Gliricidia and control than with Acacia. The sorghum yield reduction with Acacia could be largely due to competition for soil moisture

Agroforestry and Community Forestry for Rehabilitation of Degraded Watersheds on the Ethiopian Highlands

Despite the efforts made to develop Ethiopian agriculture over the years, the problems of hunger, famine, and malnutrition and land degradation still linger and present the greatest threat to the survival of the nation. With the new thrust to produce more food using high input and single crop farming, today’s farmers grow only one or two crops in monoculture systems. The traditional diversification of farmlands, which arguably has been the source of sustenance in rural Ethiopia since time immemorial, has largely been abandoned. Furthermore, deforestation, accelerated soil erosion, and land degradation are now serious problems in Ethiopia. As a result crop and livestock yields are generally very low and the recent drought has aggravated the situation. The land use system is associated with the decrease in the size of holdings both for arable and grazing lands. Thus there is a continued trend toward the conversion of forested and marginal lands to agricultural lands, resulting in massive environmental degradation and a serious threat to sustainable agriculture and forestry. While agroforestry should not be taken as a panacea for land-use problems in Ethiopia, it may be considered as a potential alternative to some of the wasteful land-use practices in the country. Agroforestry is a dynamic, ecologically based, natural resources management system that, through integration of trees on farms and agricultural landscapes, diversifies and sustains production for increased social, economic, and environmental benefits for land users at all levels (World Agroforestry Center 2003). In this paper we will present different agroforestry practices and their potential, as well as research needs on the Ethiopian Highlands based on a Diagnostic and Design survey conducted by ICRAF and the Technical Committee for Agroforestry in Ethiopia in 1990. The second part of the paper will present a case study on rural tree planting on farm and community lands in the Alemaya Basin, Hararghe Highlands, Ethiopia. This study was conducted by the Alemaya University of Agriculture in the 1980s and was funded by FAO. If properly practiced and managed, these agroforestry and community forestry programs can serve as a means to alleviate problems of soil erosion and land degradation. They can also provide food, fuelwood, and fodder for the farm family. Agroforestry can be viewed as a strategy to overcome the lack of success in past tree planting by providing opportunities for both food and tree production on the same unit of land, thus reducing competition for this scarce resource. Agroforestry can also serve as a model for sustainable agriculture and forestry practices

Root production, soil organic matter, soil moisture, and sorghum yield in an alley-cropping system with Acacia saligna (Labill.) Wendl. and Gliricidia sepium (Jacq.) Walp. in the Hararghe Highlands, Eastern Ethiopia

A field experiment was conducted to study root production, soil organic matter, and moisture and sorghum yield in an alley-cropping system with Acacia saligna and Gliricidia sepium in the Hararghe highlands of Ethiopia. Tree hedgerows were planted on either side of a 4-m wide crop alley. Intra-row spacing between trees was 25, 50, and 100 cm. In October, 1994 and March, 1995 soil samples were taken at depths of 0-10 cm and 10-30 cm at 50 and 200 cm distance from the hedgerows using direct coring and mesh bags. Roots were separated from the soil by wet-sieving and root weight and root length density were determined. Measurements of soil organic carbon and total nitrogen to a depth of 0-60 cm were made. Field tensiometers were installed at 10, 30 and 60 cm depths. Soil water content was periodically monitored at similar depths. Sorghum grain yield, above-ground dry matter and height were determined. Acacia fine-root (≤2 mm) mass was significantly (p≤ 0.05) higher than for Gliricidia in the top 30 cm of soil. The presence of fine roots decreased by 55% and 40% for Acacia and Gliricidia, respectively, as the distance increased from 50 to 200 cm from hedgerows. Increase in tree root mass was accompanied by proportionally decreased crop root mass. Results of the March samples showed that the dry period is when trees allocate a higher proportion of carbon to the root system to stay competitive under the dry conditions. Leaf and twig dry matter of Acacia was significantly (p≤ 0.05) higher than for Gliricidia. Soil organic matter was lower by 20% and 10% in control and Gliricidia plots compared to Acacia plots. Soil moisture content and water potential measurements indicated that soil moisture was lower in Acacia plots than in the control and Gliricidia plots. Sorghum biomass, grain yield and height were significantly (p≤ 0.05) higher with Gliricidia and control than with Acacia. The sorghum yield reduction with Acacia could be largely due to competition for soil moisture.</p

Gum and resin bearing dryland forests of the Somali region, Southeastern Ethiopia: Diversity, structure and spatial distribution

Despite their ecological and socio-economic contributions, the lowland dry forests of Ethiopia have largely been neglected and hence experience severe deforestation and degradation challenges. It is, therefore, crucial to assess the status of the dry forest resources to formulate appropriate management strategies that facilitate their sustainable utilization. This study was undertaken to determine spatial distribution, species composition, structure, and regeneration of gum and resin-producing species in the dry forests of the Somali Regional State of Ethiopia. The recent Sentinel-2A image was procured and used to classify the area, using a supervised Random Forest Algorithm, into different land covers and vegetation types. Inside the two key vegetation types (Acacia dominated woodland and Mixed woodland), forest inventory was conducted by establishing 30 m x 30 m size quadratic sample plots. The results revealed that the study area was divided into settlement (0.2%), bare land (6.0%), undifferentiated forest (0.5%), acacia woodland (36.3%), mixed woodland (54.1%) and scrubland (2.9%). Thirty-four woody species were identified and recorded with a Shannon diversity of 3.03. The population structure showed a lack of sufficient natural regeneration. This shows that the forest containing the gum and resin-bearing species is not replacing itself as well as it should. On the other hand, if managed properly, the forest has the potential to produce various types of oleo-gum resins. Thus, implementing appropriate restoration measures is urgent to enhance natural regeneration. Moreover, formulating sustainable utilization while creating a product market of gum and resins are important consideration to ensure the conservation and sustainable use of dry forests in the region

Gum and resin bearing dryland forests of the Somali region, Southeastern Ethiopia: Diversity, structure and spatial distribution

Despite their ecological and socio-economic contributions, the lowland dry forests of Ethiopia have largely been neglected and hence experience severe deforestation and degradation challenges. It is, therefore, crucial to assess the status of the dry forest resources to formulate appropriate management strategies that facilitate their sustainable utilization. This study was undertaken to determine spatial distribution, species composition, structure, and regeneration of gum and resin-producing species in the dry forests of the Somali Regional State of Ethiopia. The recent Sentinel-2A image was procured and used to classify the area, using a supervised Random Forest Algorithm, into different land covers and vegetation types. Inside the two key vegetation types (Acacia dominated woodland and Mixed woodland), forest inventory was conducted by establishing 30 m x 30 m size quadratic sample plots. The results revealed that the study area was divided into settlement (0.2%), bare land (6.0%), undifferentiated forest (0.5%), acacia woodland (36.3%), mixed woodland (54.1%) and scrubland (2.9%). Thirty-four woody species were identified and recorded with a Shannon diversity of 3.03. The population structure showed a lack of sufficient natural regeneration. This shows that the forest containing the gum and resin-bearing species is not replacing itself as well as it should. On the other hand, if managed properly, the forest has the potential to produce various types of oleo-gum resins. Thus, implementing appropriate restoration measures is urgent to enhance natural regeneration. Moreover, formulating sustainable utilization while creating a product market of gum and resins are important consideration to ensure the conservation and sustainable use of dry forests in the region

Trade-off between forest conservation and agricultural expansion in Gura-ferda district, Southwest Ethiopia

Agricultural expansion is one of the main drivers of deforestation in Ethiopia. This study was therefore carried out to examine the trade-off between forest and agricultural land uses in Guraferda district, southwest Ethiopia. Data to estimate economic values of land use were derived from the household surveys, key informant interviews, and focus group discussions. The household surveys were carried out in four purposively selected kebeles. Within the selected Kebeles, a total of 186 sample households were selected randomly. In addition, this study used Remote Sensing (RS) to detect and quantify LULC changes that occurred in the district throughout a thirty-year study period. The study employed by Excel 2013 for solving a cost –benefit analysis and ERDAS Imagine 9.1 for image processing. The finding revealed that an expansion of agriculture/settlement and shrinkage of forest and shrub land over the last thirty-year. The forest and shrub land use decreased by 0.43 and 2.42% ha year-1, respectively, whereas agriculture/settlement and grassland increased by 9.1 and 0.64% ha year-1, respectively over the same period. The deforestation rate is estimated at 425 ha year-1 in the study area. Analysis of trade-off provides estimated forgone earnings of about ETB 79,138 ETB (1665.3 USD ha-1) and ETB 258,298.10 (5,435.5 USD ha-1) from forest conservation and crop production, respectively assuming a 20-year planning horizon and a 10% discount rate. The 425 ha of annual deforestation entails a loss of ETB 33,633,650 (707,779 USD year-1) from forest conservation and a gain of 109,776,692.5 ETB (2,310,115.5 USD) agricultural activity. Int. J. Agril. Res. Innov. Tech. 12(1): 45-55, June 202

Impact of Forest Landscape Restoration on livelihoods of rural households: A case study from Sodo District, Central Ethiopia

Ethiopia has pledged to restore 22 million ha of degraded and deforested lands by 2030. To this end, Forest Landscape Restoration (FLR) efforts are underway. But empirical studies that critically evaluated the effectiveness of FLR in the country are scanty. This study was conducted to evaluate the impact of FLR initiatives on rural households’ livelihoods in Sodo district, Southern Central Ethiopia. A two-stage random sampling technique was used to draw 260 sample households (120 households from FLR participating and 140 households from non-FLR participating). Using a structured questionnaire, data on socio-demographic characteristics such as on household heads, household assets, access to credit, land size, household income and related expenditures were gathered. Besides formal survey, key informant interviews, focus group discussions, direct field observations, and review project documents and official reports were used to gather data. The data was analyzed using descriptive statistics and Propensity Score Matching (PSM) technique. The results showed that FLR participants are likely to gain higher total and crop income than non-FLR participants. The average off-farm income of FLR participants also increased by 10,252.4 ETB (200 USD). The number of beehives and the amount of honey produced was higher with FLR participants. FLR participants received more training and had better access to credit and engaged more in rearing sheep and poultry. In conclusion, to maximize impact on livelihoods, FLR initiatives should be combined with agricultural intensification and diversification as well as with business-oriented forest development activities