South-eastern Highlands Of Ethiopia Research Articles

Ethnobotany of stinging nettle (Urtica simensis Hochst. ex. A. Rich.) in the Oromia region of central and southeastern highlands of Ethiopia

BackgroundStinging nettle, Urtica simensis, has a wide range of distribution in the highlands of Ethiopia with untapped potential for a sustainable supply of healthy and nutritious food. This study was conducted to document ethnobotanical uses of U. simensis and the associated traditional knowledge of the indigenous people and to identify the factors limiting harvesting and utilization of stinging nettle in North Shewa (R4), Bale and Arsi zones of the Oromia region, central and southeastern highlands of Ethiopia.MethodsThirteen districts were purposively selected from the three zones and a total of 130 respondents were sampled, with consideration of gender, age, occupation, and wealth status. Data were collected using semistructured interviews, tour-guided field observations, and focus group discussions. IBM SPSS Statistical software package was used to analyze ethnobotanical data.ResultsPearson’s chi-square analysis showed that there is a significant association (P < 0.05) between zones and districts in the ethnobotanical knowledge of use categories. Stinging nettle plants have an average use value index of 0.91 with a central role (FL = 44.8%) as a source of food and fodder. Cultural norms and values followed by lack of knowledge and stinginess were the main limiting factor for harvesting and consumption of U. simensis. Cultural norms and values showed significantly higher correlations with the various uses of U. simensis (r2 = 0.931, p < 0.001) indicating the stigma related to stinging nettle being associated as poor man food or famine food were probably a major limiting factor for the utilization of U. simensis.ConclusionsFuture strategic policies should consider U. simensis as a source of food and fodder to fight food insecurity and improve the wellbeing of society. There is a need for local level and countrywide awareness creation, domestication, and future research on value addition and processing for effective utilization of the plant.

Supplemental Nitrate Composition of Ca and Mg Liquid Fertilizer Application on Potato &amp;lt;i&amp;gt;(Solanum tuberosum L.)&amp;lt;/i&amp;gt; to Increase Tuber Yield in Tiyo District of Arsi, Ethiopia

Field experiments were conducted at Kulumsa station of Tiyo district, southeastern Ethiopia in 2017 and 2018 off-season, to test the effect of fertilizer products on yield and yield components of potato and to evaluate the possibility of incorporating the products into input system for agricultural production. The treatment set up were 1) No input (negative control), 2) recommended rate of fertilizer (RNP) (111, 39 and 16.5 Kg ha^-1 N. P and S, respectively) from NPS and Urea, 3) RNP + 1.8 L ha^-1 LF; 4) RNP + 3 L ha^-1 LF, and 5) RNP + 4.2 L ha^-1 LF on growth performance and yield. The results showed that treatment effects were significant for potato total and marketable tuber yields. Since the effect of fertilizers on the yield of potato was consistent across seasons in Kulumsa station, combined analysis has been conducted. The highest total (46.1 t ha^-1) and marketable (42.2 t ha^-1) tuber yields were recorded with the application of recommended fertilizer (RNP) + 1.8 L ha^-1 LF and (RNP) + 3L ha^-1 LF. This treatment was even statistically superior to application of RNP alone. Compared to the control and RNP treatments, application of inorganic fertilizers with 1.8 L ha^-1 LF gave 23.4 and 14.1% more total tuber yield of potato, respectively. Similarly, RNP + 3.0L ha^-1 LF gave 20.9 and 13.7 % more marketable tuber yield of potato over the control and recommended fertilizer from inorganic sources (NPS and urea) treatments, respectively. The result further showed that application of 1.8 L ha^-1 LF with RNP fertilizer gave total and marketable potato tuber yields which is statistically at par with yields obtained from NPS plus 3.0 L ha^-1 LF. The lowest total (35.3 t ha^-1) and marketable (33.4 t ha^-1) tuber yields of potato were harvested from the plots that received neither inorganic nor fertilizers. Therefore, integrated application of liquid fertilizer along with full dose of inorganic fertilizers has been recommended for increased productivity of potato in the south-eastern highlands of Ethiopia.

Effect of Azotobacter and Pseudomonas with Mineral Fertilizer on Yield and Yield Components of Malt Barley (Hordeum vulgare L.)

The effect bio-fertilizer composed of Azotobacter and Pseudomonas spp. was investigated on yield and yield components of malt barley (H. vulgar L). The treatments which were laid at Bekoji, a potential malt barley district in the southeastern highlands of Ethiopia, Azotobacter + Pseudomonas + 46/20.2 N/P kg ha -1, Pseudomonas +46/20.2 N/P kg ha -1, 46/20.2 N/P kg ha -1, Azotobacter +46/20.2 N/P kg ha -1, Azotobacter + Pseudomonas, Azotobacter, Pseudomonas, C- (uninoculated and unfertilized) in randomized complete block design(RCBD) with three replications. Results indicated that application of the bio-fertilizer treatments alone resulted in the minimum performance of different agronomic parameters studied, while inorganic fertilizer application with dual inoculation with Azotobacter + Pseudomonas gives the highest and significant effect on grain yield, harvest index, biological yield, plant height, and thousand seed weight as compared to other treatments. But this trend was not observed in the number of spikes for that case the result was reversed. Hence, the study showed that the use of chemical fertilizer along with dual inoculation (Azotobacter +Pseudomonas) should be considered as a component of inputs especially in inorganic farming systems of malt barley production. Keywords : Malt barley, Azotobacter, Pseudomonas, Bio-fertilizer. DOI: 10.7176/JNSR/12-11-04 Publication date: June 30 th 2021

Evaluation of Root Noduletingrhizobial Strains for Fababean Crop at Kulumsa, Southeastern Highlands of Ethiopia

The response of fababean to seed inoculation with ninestrains of Rhizobium leguminosarum along with recommended phosphorous from TSP fertilizer was examined in field experiments at a total of five sites from 2013 to 2015 at Kulumsa in the southeastern highlands of Ethiopia. Full (18– 46 kg N–P2O5 ha<Sup>-1</sup>) and half doses nitrogen and phosphorous from inorganic source (DAP), and no input at all were also included in the treatments. The experiment was laid out in randomized complete block design with three replications. The result of 2013 trial showed seed inoculation with root noduleting rhizobium strains significantly improved the productivity of fababean. The highest grain yields of fababean were obtained from seed inoculations withstrainsEAL-110, FB-Murd, 1035 and 1018 along with recommended phosphorous from TSP.

Hierarchical Cluster Analysis on Potential Resource of Nitrogen Fixing Bacteria at Wheat Monocrop Production Districts of Bale,Ethiopia

Wheat monocrop production system at south eastern highlands of Ethiopia is a threat to productivity and adoption of high value highland pulses such as Faba bean which are the most important pulse crop in Ethiopia. Thirty faba bean nodulating isolates trapped from soil collected from twenty eight locations of Bale zone were characterized for possible diversity.For these purposes numerical taxonomy by multivariate cluster analysis based on physiological characteristics was used and according to which entire test isolates were grouped .Dendrogram constructed from cluster analysis of 56 phenotypic traits, grouped them into three clusters and one un-clustered positions at 53% relative similarity. Cluster III contained 58% of the test isolates that were grouped together with the reference strains Rhizobium leguminosarum (FBEAL-110), suggesting that besides to cmmonly nodulated on the study area were also phenotypically diverse. Furthermore, the result indicates the existence of strains in the collection, which can tolerate environmental stresses, thus can be developed into inoculant for highland pulses’ inoculation and production in Ethiopia and beyond. Keywords : Cluster analysis, Monocropping, Rhizobium leguminosarum DOI : 10.7176/JBAH/9-19-02 Publication date :October 31 st 2019

Decades of Faba Bean (Vicia faba L.) Breeding for Better Grain Yield and Seed Size has Inadvertently Reduced G × E Interaction and Increased Inter-Temporal Performance Stability

Thirteen faba bean varieties including 11 released between 1977 and 2007 and two promising genotypes were evaluated at seven contrasting environments in the central and southeastern highlands of Ethiopia during the main cropping seasons of 2007/2008 and 2008/2009. The objectives of the study were to evaluate temporal genetic progresses made over three decades of breeding in patterns of G × E interaction and performance stability of the varieties developed in due course for grain yield and seed size of faba bean. The study was conducted using a randomized complete block design with four replications. Regression coefficients (bi) of genotypes over years of release as a stability parameter showed a steadily but smoothly decreasing trend at the rate of 9.0 × 10−3 year−1 (r = −0.60; P ≤ 0.01), indicating that varietal performance stability increased with time. Trend analysis based on AMMI stability value (ASV), genotypic selection index (GSI), Shukla stability variance (σi2), and Kang’s rank sum (KRS) values of grain yield also revealed an increasing yield stability over the years of release. For seed size, GSI and KRS values decreased with time. The coefficient of variability (CV) for grain yield and seed size also tended to temporally decline while sustainability index (SuI) increased across the year of releases indicating that there was no performance stability sacrificed to achieve the greater yield potential with larger seed size. Therefore, this data support that selection of new genotypes that yield well at multiple environments, specifically genotypes with large seed size and resistance to disease as a method to increase performance stability.

Outstanding Performance of Recently Released Linseed (Linum usitatissimum L.) Variety (Yadanno) and Other Linseed Lines in South Eastern Highlands of Ethiopia

Yadanno is a common name for the linseed variety developed through hybridization and continuous selections using pedigree method. Yadanno was selected, developed and released by Kulumsa Agricultural Research Center for Arsi and West Arsi Zones and similar agro-ecologies of linseed growing areas of Ethiopia. Specifically, it was tested at Kulumsa, Bekoji, Asasa and Kofele for three years (2010/11 to 2012/13) and verified in 2014/15 at listed locations for 2016 official release. As a result, Yadanno consistently produced better mean seed and oil yields than the standard check (Kulumsa-1) and the local check over three years. Likewise, it proved to be resistant to wilt ( Fusarium oxysporum f.sp. lini ), powdery mildew (Oidium sp.) and pasmo (Septoria linicola) diseases. The results of the multi-location trials revealed that Yadanno was superior in seed and oil yields performance across years and locations. Besides, it is stable variety based upon different stability parameters. Keywords : Edible Oil; Yadanno ; Linseed; Variety registration DOI : 10.7176/JBAH/9-7-05 Publication date : April 30 th 2019

AMMI and GGE Biplot Analysis of Linseed (Linum usitatissimum L) Genotypes in Central and South-Eastern Highlands of Ethiopia

Twelve linseed genotypes were evaluated in 13 environments during the main cropping season in central highlands of Ethiopia. The objective of the study was to determine the magnitude and pattern of G × E interaction and yield stability in linseed genotypes. The study was conducted using randomized complete block design with 3 replications. Genotype × environment interaction and yield stability were estimated using the additive main effects and multiplicative interaction and site regression genotype plus genotype × environment interaction biplot. Pooled analysis of variance for seed yield showed significant (p ≤ 0.001) differences among the genotypes, environments and G × E interaction effects. This indicated that the genotypes differentially responded to the changes in the test environments or the test environments differentially discriminated the genotypes or both. Environment effect was responsible for the greatest part of the variation, followed by G × E interaction and genotype effects, indicating spatial and temporal replications of linseed yield trials. The first three multiplicative component terms of AMMI were found to be significant. The first two multiplicative component terms sum of squares, with their cumulative degrees of freedom of 44, explained 62.9% of the interaction sum of squares. No single variety showed superior performance in all environments but CI-1525 demonstrated top ranking at six of the thirteen environments. The application of AMMI and GGE biplots facilitated the visual comparison and identification of superior genotypes, thereby supporting decisions on variety selection and recommendation in different environments

A GIS‒based habitat suitability model for the mountain nyala tragelaphus buxtoni in the southeastern highlands of Ethiopia and its implication for conservation

A GIS‒based habitat suitability model for the mountain nyala tragelaphus buxtoni in the southeastern highlands of Ethiopia and its implication for conservation

Malting barley response to integrated organic and mineral nutrient sources in Nitisol

PurposeDepletion of soil fertility accounts for the low yield and quality of malting barley (Hordeum vulgare) in Ethiopia. Mineral fertilizers can counteract nutrient depletion but are unaffordable by low-input farmers. Organic amendments can contribute to correct soil degradation but are often unavailable in the required amounts. Therefore, this experiment was conducted to investigate the effects of combined use of organic and mineral amendments on the yield and quality of malting barley, and on selected soil chemical properties at Lemu-Bilbilo district in the southeastern highlands of Ethiopia.MethodsEight treatments were arranged in randomized complete block design with three replications to compare sole and integrated applications of organic and mineral nutrient sources on crop performance attributes and selected soil characteristics.ResultsApplication of 2.82 t ha−1 compost or 1.07 t ha−1 farmyard manure (FYM) along with 18–10 kg ha−1 N–P gave 4234–4443 kg ha−1 grain yield with 15–17 and 32–39% increase over sole organic amendments and control, respectively, and 757% economic benefit. Combining organic and mineral fertilizers also gave 7–17 and 1–6% increase in available soil P and total N content of the soil.ConclusionCombined application of 50% recommended compost (RC) or 50% recommended FYM (RFYM) + 50% recommended NP (RNP) or 33% RC + 33% RFYM + 33% RNP enhanced yield, grain quality, soil attributes and economic benefits. Therefore, integration of organic and mineral amendments is recommended as best agronomic and economic optimum soil fertility management options for sustainable malting barley production in the southeastern highlands of Ethiopia.

Bread Wheat Varietal Development and Release in Southeastern Highlands of Ethiopia

Four improved bread wheat varieties; Mandoyu (WORRAKATTA/PASTOR), Sanate (14F/HAR1685), Obora (UTIQUE96/FLAG-1) and Dambel (AGUILAL/3/PYN/BAU//MILAN) are developed from ICARDA materials and released in 2014 and 2015, respectively for highland and mid altitude areas of Bale and similar agro-ecologies. The new varieties were tested along with three standard checks (Madawalabu, Sofumer and Tusie) and one local check (Hollandi) at three environments in 2011 to 2012 and 2012 to 2013, respectively during main cropping seasons. The two years data of regional variety trial combined over locations and years provide the newly released varieties showed that superior in grain yield performance, stability, and wide adaptation. The four newly released varieties have good protein content, good physical grain quality, resistant to stem rust, moderately susceptible to yellow rust, moderately resistant to septoria leaf blotch and comparable for leaf rust disease with the checks. The variety Mandoyu, Sanate, Obora and Dambal have been demonstrated and are being cultivated by farmers for production purpose. Hence, the cultivation of these newly released improved bread wheat varieties in the highland and mid altitude areas of major wheat growing environments of the country is highly recommended. This new variety given local name Mandoyu, Sanate, Obora and Dambel, respectively.

Contribution of participatory forest management towards conservation and rehabilitation of dry Afromontane forests and its implications for carbon management in the tropical Southeastern Highlands of Ethiopia

ABSTRACTParticipatory forest management (PFM) has been applied as an approach to create a framework for collaborative forest management between local communities and government forestry agencies. This study was designed to assess the contribution of PFM approach in improving forest status in the Southeastern Highlands of Ethiopia. Landsat satellite imageries of four years were used to evaluate the trends and rate of deforestation before and after PFM interventions. Socio-economic data were collected from sample household surveys, key participants, focus group discussions, and field observations. The results showed that there was high rate of deforestation before PFM intervention as forestland has decreased by 19% (2531 ha) between 1990 and 2000. However, after the PFM intervention (2000–2016), the forest cover has increased by 247 ha (2.2%). During this period, net 1016 ha of shrub-lands were converted into forestland owing to significant forest regeneration. In addition, most sampled households (94% and 96% from lower and upper altitudes, respectively) perceived that PFM had significantly contributed to improve forest regeneration in their locality. This study revealed that PFM can serve as a stepping stone for carbon financing mechanisms to reduce greenhouses emission and enhance carbon sinks via forest resources.

English

The effect of N and P fertilizers and weeds control on yield and yield components of linseed (Linum usitatissimum L.) were studied in South-Eastern highlands of Ethiopia at four locations during 2009/2010 and 2010/2011 main cropping seasons. Split plot design with three replications was used. The main plot was allocated for four weeding frequencies and sub-plot was allocated for eight fertilizer rates. Results indicated that tiller numbers, pod numbers and final seed yield of linseed were significantly influenced by the effects of N and P fertilizers and weeds control treatments. Results showed that W4F5 treatment produced 58% seed yield advantage over the control in combined years over locations. Similarly, W4F6 produced seed yield advantage of 57% over the control in combined years over locations. Moreover, this study revealed that W4F5 treatment resulted in 38 and 43% increment in number of pods/plant and seed yield/plant, respectively compared to the control. Thus, the present results showed that treatments W4F5 to W4F6 were superior agronomic practices for linseed production in South-Eastern highlands of Ethiopia. Likewise, twice hand weeding alone brought 53% seed yield increment as compared to unweeded check. Besides, twice hand weeding resulted in 45 and 38% increment in number of pods/plant and seed yield/plant, respectively as compared unweeded check. Results have shown that dominant broadleaved and grass weeds vary across locations. The results of economic analysis also indicated that the highest net benefits were obtained from twice hand weeding and application of 23/23 kg/ha N/P2O5 to 23/34.5 kg/ha N/P2O5. &nbsp; Key words: Fertilizer, linseed, weed.

Lactation yield: Interval level comparison of milk records for genetic improvement in Friesian vs Arsi crossbred cows in the highlands of south eastern Ethiopia

Milk recording intervals was studied by analysing 1220 lactation records of Friesian x Arsi crossbred cows kept in south eastern highlands of Ethiopia. Milk Recording Intervals (MRI) comparison was made at 15, 30 and 45 day's length. Accuracy was measured in terms of percentage difference between actual and estimated yield, Root Mean Square Error (RMSE) and coefficient of determination (R2). The study revealed that 15, 30 and 45-day MRI can estimate lactation yield accurately to extent of less than five percent error. Lactation yield estimated by 15-day MRI was marginally more accurate with higher R2 (99.6%) and lower RMSE (34.8) values compared to 30 and 45-day MRI. Simple regression analysis indicated that yield of 9th period (121-135 days) in 15-day; the 5th period (121-150 days) in 30-day and the 3rd period (91-135) in 45-day time interval provided reliable estimate of 305-day yield. The step-wise regression analysis showed that combination of more than three records did not result in increasing the accuracy of estimates. Thus 30 and 45-day MRI can be used in the estimation of lactation yield in Friesian x Arsi crossbred cows.Keywords: Accuracy, Lactation yield, Interval comparison, Test day

RESPONSE OF LINSEED (LINUM USITATISSIMUM L.) TO SEED RATES AND SEEDING METHODS IN SOUTH-EASTERN HIGHLANDS OF ETHIOPIA

The effect of seed rates on yield and yield components of linseed were studied in South-Eastern Highlands of Ethiopia at four locations during 2012/13 and 2013/14 main-cropping seasons. Randomized complete block design with three replications was used for row planting and 10m by 10m plots were used for broadcasting. The linseed variety 'Kulumsa-1' was used and sown at seed rates (kg/ha) of nine levels for row planting and six seed rate (kg/ha) levels were used for broadcasting. Results indicated that significant (P≤0.05) effects of seed rates were observed on all yield components reflecting the importance of seeding rate for linseed growth, yield and yield components. However, significant (P≤0.05) effects of seed rates were not observed on all yield components except on number of pods/plant in the case of broadcasting. The highest seed yield was recorded from 40kg/ha (2019kg/ha) and 70kg/ha (1908kg/ha) for row planting and broadcasting, respectively. This data depicted that 6% (111kg/ha) seed yield advantage was obtained by using row planting method as compared to broadcasting. Likewise, using 30kg/ha and 40kg/ha seed rates increased seed yield/ha by 6% (110kg/ha) and 9% (162kg/ha), respectively as compared to 15kg/ha in the case of row planting. Similarly, using 70kg/ha seed rate for broadcasting resulted in 6% (102kg/ha) and 7% (126kg/ha) seed yield advantage as compared to 30kg/ha and 40kg/ha seed rates, respectively. The results of economic analysis indicated that the highest net benefits were obtained by using a seed rate of 30 to 40kg/ha for row planting and 70kg/ha for broadcasting. Keywords: Broadcasting, Linseed, Row planting, Seed rate

Bulb Yield Stability in Shallot: The Case of Eighteen Shallot Genotypes Evaluated under Southeastern Ethiopia Highlands

Study was carried out to identify stable shallot genotypes with better yield performance over range of environments during 2008-2009 cropping season at south eastern highlands of Ethiopia. Eighteen shallot genotypes were evaluated including standard check (Huruta) and Local check over six environments (2 years x 3 locations) using randomized complete block design with three replications. Data was analyzed using MSTATC and IRRSTAT statistical softwares for combined analysis of variance and stability study respectively. Additive Main Effect and Multiplicative Interaction (AMMI) model was employed to handle the interaction effects. Combined analysis of variance indicated that there was highly significant difference (p<0.01) between genotypes, environments and genotype x environment (G X E) interactions. AMMI analysis confirmed that genotypes S2-68-89, DZ-SHT-57, DZSHT82, DZSHT-119 and P-403-OP-S1 were the most stable genotypes. Their regression slopes were not significantly different from one (p<0.01) and scores near zero when observed across the first Interaction Principal Component Axis (IPCA1). However, genotypes Waliso, DZ-SHT-21, DZSHT-93 and Huruta were relatively unstable when observed on AMMI bi-plots and had regression slopes significantly different from one (p<0.01). Genotype DZ-SHT-21 was the best with 17300 kg/ha mean bulb yields. Environments Shallo 2008, Sinana 2009, Shallo 2009 and Lower Dinsh 2009 had large positive scores indicating that they interacted in positive direction with the genotypes whereas environments Sinana 2008 and Lower Dinsho 2008 had negative score indicating that they interacted in opposite direction with genotypes. These environments are described as unpredictable that makes cultivar recommendation difficult or complex. This study revealed that breeding shallot genotypes for local or specific adaptation is highly important.

Litter production and nutrient cycling in two plantations and a Podocarpus falcatus dominated natural forest ecosystems in south-eastern highlands of Ethiopia

The production of litter plays a fundamental role in the biogeochemical cycle of organic matter and mineral nutrients in forest ecosystems. The amount of litter produced and nutrients returned, and their accumulation in the organic layers of Eucalyptus globulus and Cupressus lusitanica plantations, and an adjacent Podocarpus falcatus dominated natural forest were monitored over a one year period in Ethiopia. The objective of the study was to asses the general trends of nutrient cycling by litter fall under the two plantations relative to the natural forest. The results showed that annual litter production was significantly highest in the natural forest (4.4 t ha-1year-1) and least in Cupressus plantation (2.2 t ha-1year-1). Litter fall in the natural forest was of high quality and richer in most nutrients than the two plantations which behaved similarly. The annual fluxes of N, S, P, Ca, Mg and K were 1.3 to 2.3 times as much in the natural forest as in Eucalyptus and Cupressus. The organic layer under Cupressus had poor quality litter compared to Eucalyptus and natural forest which behaved similarly mainly due to the influence of the understorey vegetation on Eucalyptus organic layer. Although statistically not significant, dry mass accumulation in the organic layer of Cupressus was higher than in Eucalyptus and lower than in the natural forest, but the approximate residence time was in the order: Cupressus >natural forest>Eucalyptus. The organic layer in the natural forest had always the maximum quantity of nutrients compared to the two plantations. Except for Ca in which Cupressus far better, the other elements were accumulated in larger quantity in the Eucalyptus organic layer than in Cupressus. Overall, the results show that the Cupressus plantation is poor self fertilizing owing to the low quality homogenous materials which could result in a gradual impoverishment of the soil. Key words: Cupressus, Ethiopia, Eucalyptus, litter fall, nutrient cycling, organic layer.

Water and nutrient inputs in rainfall into natural and managed forest ecosystems in south-eastern highlands of Ethiopia

The input of rain water to the forest floor and the composition of rainfall and throughfall water were monitored between October 2001 and September 2002 in a natural and two plantation (Eucalyptus globulus and Cupressus lusitanica) forests at Munesa, southeastern highlands of Ethiopia. The proportions of throughfall to annual incident rainfall that passed through the different forest canopies were 53% under Cupressus and the natural forest and 82% under Eucalyptus. Annual nutrients deposition by rainfall varied from 0.08kg ha−1 yr−1 for Mg to 3.79kg ha−1 yr−1 for Na. Wash-off of materials deposited on the canopy surface and leaching of intracellular solutes from the canopy resulted in an enrichment of throughfall fluxes in K, Mg, Ca and Cl relative to rainfall and varied among forest types, being highest under natural and Eucalyptus forests and lowest under Cupressus. Sodium, NO3–N, NH4–N, SO4–S and PO4–P fluxes in throughfall were depleted relative to rainfall, but the magnitude of net depletion was different for the different elements; highest for Na (3.87kg ha−1 yr−1) followed by NH4–N (2.85kg ha−1 yr−1) and lowest for PO4–P (0.42kg ha−1 yr−1). The amount of canopy uptake and leaching were generally low in the dry season and increased sharply towards the wet season.

Concentrations of exchangeable bases and cation exchange capacity in soils of cropland, grazing and forest in the Bale Mountains, Ethiopia

Conversion of native forest ecosystem to cropland has considerably degraded the soil nutrient levels in the Bale Mountains, south-eastern highlands of Ethiopia. This study investigated the effects of land use change through conversion of native forest to cropland and/or grazing land on soil pH (H 2O), base cations (Ca 2+, Mg 2+, K +, Na +), CEC and percentage base saturation (PBS) in three adjacent land-use types: cropland, grazing land and native forest. A total of 108 soil samples (3 replications × 3 land-use types × 4 profiles × 3 soil depth layers, 0–0.2, 0.2–0.4 and 0.4–1.0 m) were collected for laboratory analyses. Results showed that soil pH, Na + and K +, CEC, and PBS varied significantly with respect to land use and soil depth while Ca 2+and Mg 2+ varied with soil depth ( ρ < 0.05). Conversion of native forest ecosystem to cropland during a 15-year period significantly increased soil pH and PBS while reducing Na + and K +. The CEC in the cropland was reduced by 37.7% (∼2.6% per annum) compared to the native forest, which could be attributed to the decline in organic matter concentrations. If such rapid declines in soil nutrient concentrations continue unabated, the soils will reach at the point of no return within a few decades. Although the effect of grazing on most of the properties was found to be minimal, adapting the number of stock to the carrying capacity of the land and thereby enhancing the natural regeneration, combined with proper cropland management practices could help restoring soil nutrients for sustainable agricultural production and ecosystem functions.

Soil property variations in relation to topographic aspect and vegetation community in the south-eastern highlands of Ethiopia

Study of soil property variations resulting from topographic aspect and vegetation changes will have implication on the proper management of marginal and environmentally sensitive areas. This study addressed the effects of topographic aspect and vegetation community types on soil physical and chemical properties in the Bale Mountains, south-eastern highlands of Ethiopia. At each stratified vegetation community; Schefflera– Hagenia, Hypericum– Erica– Schefflera, and Erica arborea (shrub size), and in each of the four topographic aspects, four representative soil profiles giving a total of 3 × 4 × 4 = 48 were opened and described. Soil texture, bulk density, soil pH, plant available phosphorus, CEC, exchangeable base cations, and percent base saturations were analyzed and interpreted. Except in few cases, all considered soil properties showed significant differences among vegetation communities and topographic aspects. The differences may be attributed to leaching and differences in organic matter (carbon) contents within the soil profiles due to topographic aspect-induced microclimatic differences, reflecting the response of vegetation communities to the conditions. Soil textural fractions, mainly silt and clay, bulk density, pH, plant available phosphorus, percent base saturation, CEC, and exchangeable base cations generally increased in the Schefflera– Hagenia vegetation community zone. Further studies might be required to fully understand and clarify the influence of aspect, topography and vegetation types on soil properties for site-specific soil resource management practices in this mountainous area.