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Small-scale Acacia decurrens plantation forests, established by farmers on degraded lands, have become increasingly prevalent in the Northwestern Highlands of Ethiopia. This trend has been particularly notable in Fagita Lekoma District over the past few decades. Such plantations play a significant role in addressing concerns related to sustainable agricultural land use, mitigating the adverse effects of deforestation, and meeting the livelihood and energy requirements of a growing population. However, the spatial distribution of Acacia decurrens and the essential remote sensing and environmental variables that determine its distribution are not well understood. This study aimed to model the spatial distribution of Acacia decurrens plantation forests using PlanetScope data and environmental variables combined with a species distribution model (SDM). Employing 557 presence/absence points, noncollinear variables were identified and utilized as input for six SDM algorithms, with a 70:30 split between training and test data, and 10-fold bootstrap replication. The model performance was evaluated using the receiver operation characteristic curve (AUC) and true skill statics (TSS). The ensemble model, which combined results from six individual algorithms, was implemented to predict the spatial distribution of Acacia decurrens. The highest accuracy with the values of 0.93 (AUC) and 0.82 (TSS) was observed using random forest (RF), followed by SVM with values of 0.89 (AUC) and 0.71 (TSS), and BRT with values of 0.89 (AUC) and 0.7 (TSS). According to the ensemble model result, Acacia decurrens plantation forests cover 22.44% of the district, with the spatial distribution decreasing towards lower elevation areas in the northeastern and western parts of the district. The major determinant variables for identifying the species were vegetation indices, specifically CVI, ARVI, and GI, with AUC metric values of 39.3%, 16%, and 7.1%, respectively. The findings of this study indicate that the combination of high-resolution remote sensing-derived vegetation indices and environmental variables using SDM could play a vital role in identifying Acacia decurrens plantations, offering valuable insights for land use planning and management strategies. Moreover, comprehending the spatial distribution's extent is crucial baseline information for assessing its environmental implications at a local scale. [ABSTRACT FROM AUTHOR]

The current study is aimed at investigating the level of polycyclic aromatic hydrocarbons (PAHs) and bis(2-ethylhexyl) phthalate (BEHP), which pose a potential risk to human health, in soil samples collected from a teff-Acacia decurrerns-charcoal production system (TACP system) in northern Ethiopia. Soil samples were collected from the TACP system and from an adjacent teff monocropping system (TM system) from 0 to 20 cm soil depth. Individual PAHs and total concentrations of PAHs and BEHP generally exhibited no significant variation between the TM and the TACP systems over three rotations. In the land-use systems, the mean concentration of PAHs decreased in the order phenanthrene > fluorene > pyrene > chrysene. Fluorene (22.84–24.69 ng g−1 dry soil), pyrene (21.99 ng g−1), and chrysene (21.79 ng g−1) were detected in the TACP system only, suggesting that they were from charcoal production. The maximum concentration of BEHP recorded in the soil samples was 104.00 µg g−1, which could be attributed to the polyethylene (PE) bags used for planting the Acacia decurrens seedlings of the TACP system. In soil samples, the sum of all PAHs analyzed ranged from not detected (ND) to 170.69 ng g−1, which is below the limits of prevention established by European regulations for soils (3000 ng g−1) and previous studies. Carcinogenic equivalent (BaP-TEQ) and mutagenic equivalent (BaP-MEQ) concentrations calculated for the individual PAHs in the land-use systems ranged from ND to 0.374 ng g−1 and from ND to 0.218 ng g−1, respectively, which is far below many international safety standards. Our results indicate that the charcoal production and the use of the charcoal residues as soil amendment in the TACP system is safe concerning soil contamination by PAHs and BEHP and the risk of cancer and mutation. [ABSTRACT FROM AUTHOR]

Agroforestry innovations (AFI) are a component of Ethiopia's mixed farming system promoted as an alternative livelihood activity for fulfilling home consumption needs and financial earnings. We evaluate the financial profitability of three AFI systems in the Amhara region of Ethiopia, namely acacia, bamboo, and eucalyptus, based on data from 327 farmers. Farmers primarily employ intercropping for establishing eucalyptus and acacia AFI, whereas bamboo is planted as a single crop due to its spreading root system interfering with other crops. Virtually, the indicators of the discounting analysis demonstrated the viability of AFI investments under smallholders. The benefit-cost ratio (BCR) is the highest for eucalyptus-cum-wheat (4) and the lowest for acacia-cum-maize (2.16) production systems. Internal rate of return (IRR) values (9%-37%) for all AFI are higher than the current discount rate (7%), with bamboo being the most viable. The AFI remain financially feasible up to a 20% prospective revenue shock. The profitability of AFI is unstable due to market volatility caused by fluctuations in demand and political instability. Based on our findings, we recommend further research on demand, supply, and market location to design appropriate adjustments to national agricultural policy interventions. [ABSTRACT FROM AUTHOR]

The nutritional value of browsing species is being affected, camel movement is being disrupted, and camel feed resources appear to be being substantially degraded by climate change and its variations. This study explores the effects of season and location on the composition of nutrients and in vitro dry matter digestibility of the main browse species utilized as camel feed. Using an ANOVA model. Lannea rivae had an average DM content of 87.23% while Acacia brevispica had a range of 95.58%. There are no statistically significant variations (p>0.05) in the ash content of browsing species, which ranges from 2.56% in Acacia mellifera to 18.66% in Grewia evolute. The CP content of Lannea rivae in Maerua triphylla ranged from 6.19% to 27.24%. During the wet season, there is a statistically significant difference (p<0.05). On the other hand, Grewia evolute's CP contents varied from 24.56% to 10.44%, showing a significant difference (p<0.05). The results showed that Acacia etabaica had an NDF content that ranged from 25.63% to 72.10% Lannea rivae. Lannea rivae had the greatest ADF content (30.53%), and Grewia tembensis had the lowest (8.20%), with the difference being statistically significant (p<0.05). Grewia villosa in Lannea rivae had an ADL content that ranged from 2.82% to 15.86%. There is a statistically significant difference (p<0.05) during the dry season. During the wet season, the NDF concentration of Maerua triphylla in Boscia mossambicensis varied from 38.33% to 62.43%. The lowest ADF content was found in Acacia etabaica (22.47%), while the highest was found in Boscia mossambicensis (42.56%). The distinction is statistically significant (p<0.001). Grewia evolute contained 2.82% to 15.86% Acacia tortilis ADL. During the dry season, Dichrostachys cinerea had the lowest cellulose concentration (3.68%), whereas Euphorbia nubica had the greatest (18.77%). The study's conclusions indicate that the location is irrelevant. NDF, ADF, and ADL fiber fractions and chemical composition (DM, Ash, and CP) did not differ substantially (P<0. 05). The effects of location and season on the chemical and fiber compositions and nutritional value of browse species for dromedary camels (Camelus dromedarius) are clarified by this study. To identify other variables that affect the nutritional composition of browsing species, more investigation is required. [ABSTRACT FROM AUTHOR]

Acacia saligna is a multi-purpose tree. However, enquiries exist among beekeepers on its importance for honeybees in Tigray region of Ethiopia. The aim of this study was to investigate the effects of A. saligna pollen on Apis mellifera adult worker bees. Feeding trial was conducted on honeybee collected polyfloral pollen (PFP), honeybee collected A. saligna pollen (HCAP) and manually collected A. saligna pollen dust (MCAP) at various level of inclusion. The HCAP and MCAP pollen types were mixed with PFP pollen at a ratio of 1:4, 3:2 and 1:0 to make seven pollen feed treatments. Newly hatched day-old cohort worker bees were collected from one colony and trapped from the sealed brood with a meshed plastic bag before hatching. A ten-day indoor cage experiment was carried out after setting up twenty worker bees per cage. The result showed no statistically significant difference on worker bee mortality and abnormality due to treatment diets, except that higher level of A. saligna pollen inclusion (> 60%) in the diet reduced intake. Secondary metabolites analysis showed higher alkaloids (4.8%) in PFP, total flavonoids of 29.66 mg QE/g in HCAP and 20.61 mg GAE/g phenol in MCAP. The finding implied A.saligna has apicultural value as dry season pollen source rather than considering it as poisonous. [ABSTRACT FROM AUTHOR]

A tef-Acacia decurrens-charcoal production rotation system, a unique indigenous climate-smart agricultural technology of northwest Ethiopia, is increasingly seen as a promising strategy for improving soil properties. This study investigated the effect of the tef-Acacia decurrens-charcoal production rotation system on soil properties. In total, 112 soil samples (7 treatments × 4 depths × 4 replicates) were collected and analyzed inside and outside randomly selected charcoal production spots in the tef-Acacia decurrens-charcoal production rotation system and from an adjacent tef monocropping system. The soil properties examined generally exhibited significant variation between the tef monocropping system and the tef-Acacia decurrens-charcoal production rotation system, and between soil depths, as well as with respect to charcoal production spots in the system. The system resulted in a significant increase in SOC, TN, available phosphorus, available sodium, available nitrate and ammonium in general, and in total contents of K, P and Mn in the 0–20 cm depth. Charcoal production in the system significantly increased the total content of P, Al, and Fe, as well as the available nitrate and sulfate in the charcoal production spot. The variation in soil proprieties between the land use types and with respect to charcoal production spots in the TACP system were possibly due to the effect of the Acacia decurrens trees, and fire and fine charcoal residues from charcoal production, indicating the capacity of the tef-Acacia decurrens-charcoal production rotation system to improve soil properties. [ABSTRACT FROM AUTHOR]

Background: Allometric equations are used to estimate biomass and carbon stock of forests. In Ethiopia, despite the presence of large floral diversity, only a few site-specific allometric equations have been developed so far. This study was conducted in the Omo-Gibe woodland of south-western Ethiopia to develop an allometric equation to estimate the Above-ground Biomass (AGB) of the four Acacia species (Senegalia polyacantha, Vachellia seyal, Vachellia etbaica and Vachellia tortilis). Fifty-four (54) Acacia trees were sampled and measured within 35 temporarily established square plots. In each plot, dendrometric variables were measured to derive the models based on combinations of Diameter at Breast Height (DBH), height, and wood density as predictor variables. Model performance was evaluated using goodness-of-fit statistics. The biomass was compared using four allometric biomass models that have been widely used in the tropics. Results: The model containing DBH alone was more accurate to estimate AGB compared to the use of multiple predictor variables. This study, therefore, substantiated the importance of site-specific allometric equations in estimating the AGB of Acacia woodlands. This is because a site-specific allometric equation recognizes the environmental factors, vegetation types and management practices. Conclusions: The results of this study contribute to a better understanding of allometric equations and an accurate estimate of AGB of Acacia woodlands in Ethiopia and similar ecosystems elsewhere. [ABSTRACT FROM AUTHOR]

We studied the effects of Acacia albida on the growth and yield of wheat, maize, and teff with increasing distance from trees in Ethiopia in the 2014/2015 cropping season. The treatments comprised four radial distances of 1.5m, 3.5m, 5.5m, and 12.5m as a control away from the tree with three replications. Results showed that higher wheat yields were recorded at 5.5m and 3.5m than at 12.5m, with yield increments of 11 and 12%, respectively compared to 12.5m. The highest maize yield was obtained from 3.5m, with a yield advantage of 12.3% compared to 12.5m. Teff yield increased with increasing distance from the tree trunk. Wheat and maize yield gains near the canopies may be associated with higher organic matter and soil nutrients, while their yield reduction with decreasing distance from the tree may be associated with the shading effect of tree canopies. Wheat was the most compatible crop when integrated with A. albida under shade conditions followed by maize, while teff was highly susceptible to shading effect. We suggest that integrating A. albida with the right crops and appropriate tree management could enhance crop yield. Lopping is required before sowing teff and maize with A. albida to minimize shading effects [ABSTRACT FROM AUTHOR]

Acacia seyal is one of the multipurpose parkland agroforestry tree species in eastern and southern Africa. It is a common on-farm tree in the Rift Valley of Ethiopia, but information is limited on its effect on soil properties and sorghum growth and yield. The study was conducted to evaluate its effect on selected soil properties and sorghum growth and yield in Guba Lafto district of northern Ethiopia. Six isolated and closely comparable Acacia seyal trees growing on sorghum farms were purposely selected, and plots were marked under the canopy of trees with three radial distances (0–2 m, 2–4 m, and 4–6 m) and one outside of the tree canopy (10 m away from any tree). Soil samples from each distance zone were taken between 0–20 cm and 20–40 cm soil depths for soil property analysis. Four quadrates with 1 m2 at each distance zone in four directions were laid for sorghum growth and yield attribute valuation. The results showed that only total nitrogen (TN) was significantly higher (P < 0.05) at the subsoil layer under the canopy compared to an open area, while other selected soil parameters were not affected by the tree species. Sorghum biomass yield (P = 0.006) and grain yield (P = 0.025) were significantly lower under the canopy of the trees than in the open area. Generally, Acacia seyal had little effect in improving soil properties and showed a negative effect on sorghum yield and growth. Further research on its effect under wide area coverage of parkland system should be performed to bring a radical shift on the intercropping farming system. [ABSTRACT FROM AUTHOR]

Drought stress (DS) is the most impacting global phenomenon affecting the ecological balance of a particular habitat. The search for potential plant growth-promoting rhizobacteria (PGPR) capable of enhancing plant tolerance to drought stress is needed. Thus, this study was initiated to evaluate the effect of inoculating Acacia abyssinica seedlings with PGPR isolated from rhizosphere soil of Ethiopia to enhance DS tolerance. The strains were selected based on in vitro assays associated with tolerance to drought and other beneficial traits such as salinity, acidity, temperature, heavy metal tolerances, biofilm formation, and exopolysaccharide (EPS) production. The strains with the best DS tolerance ability were selected for the greenhouse trials with acacia plants. The results indicate that out of 73 strains, 10 (14%) were completely tolerant to 40% polyethylene glycol. Moreover, 37% of the strains were strong biofilm producers, while 66 (90.41%) were EPS producers with a better production in the medium containing sucrose at 28 ± 2°C and pH 7 ± 0.2. Strains PS-16 and RS-79 showed tolerance to 11% NaCl. All the strains were able to grow in wider ranges of pH (4–10) and temperature (15–45°C) and had high tolerance to heavy metals. The inoculated bacterial strains significantly (p ≤ 0.05) increased root and shoot length and dry biomass of acacia plants. One of the strains identified as P. fluorescens strain FB-49 was outstanding in enhancing DS tolerance compared to the single inoculants and comparable to consortia. Stress-tolerant PGPR could be used to enhance acacia DS tolerance after testing other phytobeneficial traits. [ABSTRACT FROM AUTHOR]

Reliable morphological identification of genetic entities within the Acacia saligna (Labill.) H.L. Wendl. species complex is difficult due to its high phenotypic plasticity, but essential due to its extensive use and ongoing development as a multipurpose agroforestry species in many countries. Acacia saligna, introduced into Ethiopia as a conservation tree in the 1980s, is recognised as a valuable multipurpose tree for fodder, fuelwood, and timber. Phenotypic variation is high, but the genetic diversity in the naturalised resource is unknown. We assessed the level of genetic diversity contained within, and genetic divergence among, five naturalised populations of A. saligna in Tigray, northern Ethiopia. Additionally, we used a Bayesian analysis approach to assign individuals of unknown taxonomic affinity in Tigrinian populations to one or more of the five known genetic entities present across the species' natural range in Western Australia. Results suggest that naturalised populations of A. saligna established in Tigray have moderate to high levels of allelic genetic diversity, and genetic divergence among populations is low to moderate. The majority of Tigrinian individuals were assigned to the north-western lindleyi genetic entity (75.75%) or to the lindleyi genetic entity (7.57%). Knowledge of locally available genetic diversity, combined with additional genetic resources from Australia, will help researchers establish provenance resource stands that can provide a sound basis for an improvement programme. The programme will produce a range of A. saligna types for different agroforestry systems and for adoption by the farming community and forestry companies, thus supporting livelihood improvement and rehabilitation of degraded landscapes. [ABSTRACT FROM AUTHOR]

Continuous conversion of land for different agricultural production purposes has resulted in degradation of soil resources. Rehabilitating soil quality through sustainable land management is one of the most pressing agenda in agriculture. Hence, this study was conducted to evaluate the trends of major soil quality after the introduction of A.decurrens tree-based farming in Guder watershed. Soil samples were collected from 5 land use types, 2 soil depths, and 3 slope positions with 3 replications and then analysed for selected soil physicochemical quality indicators. Selected soil physicochemical indicators were subjected to three-way ANOVA. The result revealed that the highest clay particles and soil bulk density were recorded at A.decurrens tree farmland and cropland soils, respectively. The maximum soil pH was recorded from natural forest (5.99), subsurface soil layer (5.56) and lower slope (5.57). The lowest soil organic carbon and total nitrogen contents were observed in cropland. Greater available phosphorus (13.58) mg kg−1 was obtained in the topsoil depth of A.decurrens tree farmland at the lower slope. Among the studied soil quality indicators total nitrogen, cation exchange capacity and soil pH were strongly and positively correlated with soil organic carbon. The finding of this study showed that shifting of cereal based into A.decurrens tree-based farming by smallholder farmers can improve the fertility and health of soils and then boost crop productivity. Therefore, the right integration of A.decurrens tree in the farming system can be an alternative approach to reverse soil quality deterioration in degraded agricultural landscapes of Ethiopia. [ABSTRACT FROM AUTHOR]

Acacia polyacantha is a fast growing indigenous tree legume that can be integrated with crops as parkland agroforestry system. Farmers keep Acacia polyacantha on their farmlands mainly for fuel wood, animal fodder, farm tools and construction. However, quantitative information on the effect of Acacia polyacantha on soil fertility improvement and socioeconomic benefits is lacking. The effect of Acacia polyacantha on soil fertility and its contribution to household income was evaluated in La'ilay Adiyabo district, northern Ethiopia. At three radii distances, 36 soil samples were collected from two soil depths from 24 trees in cultivated and uncultivated land using a 3 × 2 × 2 × 3 factorial arrangement in randomized complete block design (RCBD) replicated three times. The effect of planting Acacia polyacantha trees on household income was estimated using Ordinary Least Squares based on data collected from a sample of 120 randomly selected farm households. Total N, OC, OM, CEC and exchangeable K levels were significantly higher under the canopies of Acacia polyacantha than outside (p < 0.05). The nutrient levels decreased significantly with increasing soil depth. Planting Acacia polyacantha trees was found to positively and significantly influence household income, in which case the aggregated monetary value of the different products from Acacia polyacantha contributed 13.7% to total household income, which is significant. However, land size was also found to be crucial; and the role that Acacia polyacantha trees play can be further increased through efficient use and management of agroforestry land. [ABSTRACT FROM AUTHOR]

In the arid, low biomass producing areas of Ethiopia, Acacia woodlands suffered a severe degradation due to exploitation for various uses, and conversion to grazing and cultivated lands. However, little is known on the impact of agricultural land uses on soil organic carbon (SOC), total nitrogen (TN) stocks, and other soil quality indicators. This study was planned to evaluate SOC and TN stock changes under parkland agroforestry (PAF), managed pastureland (MPL), and treeless cropland (TLCL) regimes by considering the remnant protected woodland (PWL) as a reference. We found that SOC and TN stocks were significantly higher in PWL and MPL areas. Conversion of Acacia woodlands to MPL, PAF, and TLCL resulted in the loss of SOC stock by 23, 50, and 56%, respectively. Higher SOC and TN stocks were found under PWL (144.3 Mg ha−1) and MPL (108.2 Mg ha−1). Significant changes in available phosphorous (P), exchangeable cations, and cation exchangeable capacity were observed following the woodland conversion to different land use types. Available P was the highest in MPL compared with the other land use regimes. Within the study area, the MPL land use type was the best land management option for protecting SOC and TN soil stocks. [ABSTRACT FROM AUTHOR]

Continued conversion of woodlands into grazing and farmland is seriously undermining the natural ecosystem of the dry and fragile Rift Valley areas of Ethiopia. This study investigated the effects of land-use change on soil organic carbon (SOC), total nitrogen (N), pH, exchangeable bases, cation exchange capacity (CEC) and base saturation (per cent) in three adjacent land-use types: controlled grazing, open-grazing and farmland. A total of 81 soil samples were collected and analysed. Contents of SOC and total N decreased drastically in open-grazing and farmland ( p < 0·001), and were significantly higher in the top 0·2 m than in the subsurface soil layer. Compared with the controlled grazing, reductions in the contents of SOC and total N in the top 1 m soil layer were 22-30 and 19 per cent, respectively, due possibly to the decrease in plant biomass input into the soil and the fast decomposition of organic materials. Long-term cultivation had significantly increased the concentration of exchangeable K. Exchangeable Na was high in the lower layers, while Mg was higher in the top surface soil. CEC also varied with soil depth ( p = 0·016); it was higher in the topsoil than in the subsurface soil, which may be, among others, due to the differences in soil organic matter distribution with depth. Although these semi-arid soils are known to have low organic carbon and CEC levels, the values from the current study area are critically low, and may indicate the further impoverishment of the soils under high agricultural and grazing pressures. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Leguminous trees play an important role in agroforestry in Ethiopia, but studies of their rhizobial symbionts are scarce. In earlier studies, we surveyed natural nodulation of native leguminous trees growing in different agro-ecological zones in Southern Ethiopia, isolated 400 rhizobia, and characterized them based on different phenotypic and genotypic methods. In the present study we characterized 18 strains belonging to the genus Mesorhizobium, isolated from nodules of Acacia abyssinica, A. senegal, A. tortilis and Sesbania sesban. Phylogenetic analysis of nearly full-length 16S rRNA gene grouped the test strains into three distinct clades separated from all currently recognized Mesorhizobium species. Three divergent strains formed separate branches while the other 15 strains formed three distinct groups, genospecies I–III. Grouping of the isolates under study based on the house-keeping genes recA, gyrB, rpoB and gltA were consistent and in agreement with that of 16S rRNA. Similarly phylogenetic relationships based on the symbiosis-related genes nodC, nodA and nifH were generally similar to those shown by the core genes, suggesting that these Acacia and Sesbania symbionts have a long history of separate evolution within Mesorhizobium. Cross inoculation experiments demonstrated a large variation in the ability of the test strains to elicit effective nodules. The Sesbania isolates, occupying a distinct clade in the nodC phylogenetic tree, formed effective nodules only with this host legume. The study strongly suggests that this collection of Mesorhizobium strains comprises several new species, and also indicates the role of the symbiotic genes in determining the host range of these bacteria. [Copyright &y& Elsevier]

Abstract: Although several proxies have been proposed to trace the course of environmental and climatological fluctuations, precise paleoclimate records from the tropics, notably from Africa are still sorely lacking today. Stable carbon isotopes (δ 13C) in tree rings are an attractive record of climate. In this study, the patterns and climatic signals of δ 13C ratios were determined on tree rings of deciduous (Acacia senegal, Acacia tortilis, Acacia seyal) and an evergreen (Balanites aegyptiaca) species, from a semi-arid Acacia Woodland in Ethiopia. δ 13C inter-annual patterns are synchronous among the co-occurring species. A declining trend with time was observed in δ 13C, notably for B. aegyptiaca, which could be due to anthropogenic increases in atmospheric CO2 concentration and decrease in atmospheric δ 13C. Tree ring δ 13C values of all the species revealed significant negative correlation with precipitation amount but not with temperature and relative humidity. The δ 13C series of the deciduous species shows a higher correlation (r =−0.70 to −0.78) with precipitation than the evergreen species (r =−0.55). A master δ 13C series, composed of the average of the three Acacia species, displayed stronger significant correlation (r =−0.82) than any of the individual species δ 13C series. The weak relationship between temperature and δ 13C in this study indicates that photosynthetic rate is not a significant factor. Moisture stress, however, may have a direct impact on the stomatal conductance and explain the strong negative relationship between δ 13C and precipitation. The results demonstrate the potential of δ 13C in tree rings to reflect physiological responses to environmental changes as a vehicle for paleoclimatic reconstruction, which is important to understand tree response to past and future climate change. [Copyright &y& Elsevier]

Abstract: Acacia etbaica Schweinf. and Dichrostachys cinerea (L.) Wight et Arn. are among the common woody browse plants that naturally grow in many arid and semi-arid rangelands in sub Saharan Africa. An experiment was conducted to compare the voluntary dry matter intake, body weight gain, nitrogen balance, carcass composition and sensory attributes of goats supplemented with different levels of A. etbaica and D. cinerea fruits. Average initial body weight of the goats was 20.4 kg (±0.8SE) and received one of the following fruit supplementation regimes for 120 days (on body weight basis, n =4 goats per group): (1) Control, no supplement; (2) 0.5% of A. etbaica; (3) 0.5% of D. cinerea; (4) 1.0% of A. etbaica; (5) 1.0% of D. cinerea; (6) 1.5% of A. etbaica; (7) 1.5% of D. cinerea. All groups were allowed to graze/browse during the day. Compared to A. etbaica, D. cinerea fruits contained higher amounts of crude protein (182 vs 135 g/kg DM), metabolizable energy (11 vs 8.4 MJ/kg DM), and in vitro dry matter digestibility coefficient (0.7 vs 0.6). The concentrations of acid detergent fiber (ADF), sulphuric acid solubulized lignin, and tannin (soluble and condensed) were lower (P <0.05) in D. cinerea than in A. etbaica fruits. A. etbaica fruits, however, contained higher amounts of Na, K, Fe, and Zn concentrations than D. cinerea fruits. Dry matter intake was markedly higher in supplemented groups than in the control group without supplement. Similarly, body weight gain in the control group was negative and lower (P <0.05) than any of the supplemented groups. During the course of the experimental period (120 days) the group placed in the 1.5% D. cinerea fruit diet gained 2.6 kg whereas the control group lost 2.0 kg. Thus, the difference between these two groups was 4.6 kg, which suggests about 22.5% increment of the goats'' initial body weight. N retention was negative for the control group and varied little among the remaining treatment groups. Dressing percent increased with increased level of either type of fruit supplement, the highest (51.8%) being achieved at the 1.5% D. cinerea level. There was no difference in bone tissue across treatment groups. D. cinerea fruit intake also resulted in juicy/watery flavor and tender carcass. D. cinerea fruits appeared to have no adverse effects when included at the highest level (1.5%) and could be collected and stored as dry season supplement to smallholder goats. This study shows that poor farmers can increase goat performance substantially through supplement feeding with wild fruits. Areas in Ethiopia originally set aside for provision of ecological services and biodiversity protection can also be used for wild fruit production and feeding of small stock. The effect of increasing D. cinerea fruits above the 1.5% body weight level should be a focus of future investigation. Further work on deactivation mechanism of tannins is required for A. etbaica fruits included at levels higher than 1.0%. [Copyright &y& Elsevier]

The diversity of 110 rhizobial strains isolated from Acacia abyssinica, A. seyal, A. tortilis, Faidherbia albida, Sesbania sesban, Phaseolus vulgaris, and Vigna unguiculata grown in soils across diverse agro-ecological zones in southern Ethiopia was assessed using the Biolog™ system and amplified fragment length polymorphism (AFLP) fingerprinting technique. By cluster analysis of the metabolic and genomic fingerprints, the test strains were grouped into 13 Biolog and 11 AFLP clusters. Twenty-two strains in the Biolog method and 15 strains in the AFLP analysis were linked to eight and four reference species, respectively, out of the 28 included in the study. Most of the test strains (more than 80% of 110) were not related to any of the reference species by both methods. Forty-six test strains (42% of 110) were grouped into seven corresponding Biolog and AFLP clusters, suggesting that these groups represented the same strains, or in some cases clonal descendants of the same organisms. In contrast to the strains from S. sesban, isolates from Acacia spp. were represented in several Biolog and AFLP clusters indicating the promiscuous nature of the latter and widespread occurrence of compatible rhizobia in most of the soil sampling locations. The results showed that indigenous rhizobia nodulating native woody species in Ethiopian soils constituted metabolically and genomically diverse groups that are not linked to reference species. [Copyright &y& Elsevier]

Oleo-gum resins, hardened resinous plant exudates obtained from some Acacia, Boswellia and Commiphora species in the lowlands of Ethiopia, have been traded for centuries both on the international and domestic markets. However, their economic contribution to the rural households is little documented. A reconnaissance survey was carried out in Liban, one of the administrative zones in the Ethiopian Somali National Regional State, to investigate major oleo-gum-resins collected for commerce and their economic contributions to rural households. The results showed that five types of oleo-gum-resins are collected for commerce in Liban. These are gum arabic obtained from Acacia Senegal, gum talha obtained from A. seyal, frankincense obtained from Boswellia neglecta and B. ogadensis, myrrh obtained from Commiphora myrrha (syn. C. molmol), C. truncata and C. borensis and hagar obtained from C. africana. The average annual cash income generated per household was estimated to be US$ 80.00. This income contributes to 32.6% of annual household subsistence, and ranks second after livestock in the overall household livelihood. The contribution from crop farming was estimated to be 12%, which is about one-third of the contribution from oleo-gum resins. These results show that oleo-gum resins obtained from the vegetation resources play a significant role in the economy of rural households in Liban. The vegetation resources and their oleo-gum resins also provide various goods and services for the rural households in Liban. Fodder for livestock, traditional medicines for human and livestock disease treatments, incense for fumigation, cultural and religious rituals, and emergency foods during droughts are among the most common. Opportunities and constraints for oleo-gum-resin-based development in Liban and other similar areas in Ethiopia are discussed. The results could be used as baseline information for evaluating the potential of the arid and semi-arid land vegetation resources of the country, to plan for extensive studies of their management, conservation and proper utilization. [Copyright &y& Elsevier]

Examines single-tree biomass functions for acacia woodland tree species to estimate the woody biomass in acacia woodlands of Rift Valley of Ethiopia. Information related to several tree species from where samples were gathered; Determination of ration between dry weight and fresh weight; Method proposed for disc sampling.

• Australian Vachellia nilotica plants have previously been classified as either subsp. indica or the "Pakistan genotype" • We used gene sequencing to better characterise this weed in Australia. • Both indica or the "Pakistan genotype" were widespread across Australia, and freely interbreeding. • The "Pakistan genotype" was also found throughout the native range of indica. • The "Pakistan genotype" is not a unique subspecies, but rather represents genetic variation within indica. Prickly acacia (Vachellia nilotica) has been the target of biological control programmes in Australia for over three decades, with little success. Control efforts may have been hindered by poor characterisation of the plants in Australia, and the ambiguous taxonomy of the species. Nine subspecies of this weed have been described, with only one subspecies identified in Australia (subsp. indica), though previous genetic screening identified a unique genotype in Australia that allegedly did not match any of the previously described subspecies (dubbed the "Pakistan genotype"). We used gene sequencing to characterise this weed in Australia, and to assess the native range distribution of the invasive subspecies. Two widespread ITS1 haplotypes were identified from 25 localities across northern Australia, corresponding to subsp. indica and the undescribed "Pakistan genotype". Many plants were heterozygous at the ITS1 locus, indicating plants with the distinct genotypes are freely interbreeding. The "Pakistan genotype", which has no defining morphological characters, was found across the native range of subsp. indica (including Ethiopia, where this subspecies has only recently been detected). The "Pakistan genotype" is not, in other words, a distinct subspecies, but simply represents genetic variation within subsp. indica. No genetic structuring was found across the native distribution of subsp. indica, so the precise provenance of the Australian plants could not be determined. Future studies should use microsatellites or genotyping-by-sequencing approaches to provide a finer-scale assessment of the provenance of the Australian plants. [ABSTRACT FROM AUTHOR]

• This study investigated local stakeholders' perceptions on expansion of Acacia decurrens -based plantation system in the Upper Blue Nile Basin. • The plantation system is positively perceived by local stakeholders. • The plantation system has the potential to bring economic benefits for small-scale farmers. • The plantation system has potential risks associated with child labour, contributing to inequalities and rising prices of staple food crops. • The plantation system has to be regularly monitored to counter its possible negative outcomes. This study was undertaken to examine local perceptions of the impacts of small-scale tree plantations, notably of Acacia decurrens (J.C. Wendl.) Willd., in Ethiopia's Upper Blue Nile Basin. A particular focus of our study was on the different dimensions of livelihood sustainability centering on economic, social, human, physical, and natural capital. The unprecedented expansion of small-scale tree plantations in degraded agricultural land can be attributed to farmers' efforts to overcome the problems of limited income options and land degradation. However, these initiatives may have differential effects in terms of maintaining the sustainability of the natural environment and rural livelihoods. Interviews conducted with farmers revealed that the plantation system has yielded rich benefits by increasing their incomes, providing them with employment and improving their social lives. The plantations have also significantly improved degraded soils, thereby increasing natural capital. However, associated risks have also been found related to rising food prices, caused by a shift from annual to perennial crops and growing inequalities, with small farmers or those with limited financial resources having fewer options to invest in plantations. Moreover, in the face of such a positive overall impact of the plantation systems, the regulation of child labor, a potential issue, could become difficult. Apart from measures to address the issue of child labor, improved infrastructure and market access are required to help balance food security and plantation systems through functioning markets and financial systems that enable economically impoverished farmers to participate in this business. These findings offer important insights for research and policies seeking to sustain small-scale farmers' tree plantation systems, land use, and rural livelihoods. [ABSTRACT FROM AUTHOR]

Background: In Ethiopia, about 92.3% of all the fuelwood (firewood and/or charcoal) is consumed for cooking, heating and lighting purposes by domestic households and the demand is growing from 10 to 14%. However, there are little/no practical experiences or documented indigenous knowledge on how traditional people identify and select high fuelwood producing plant species with short rotation periods at Boset District. Therefore, the present study was aimed at: (1) selecting and documenting high fuelwood producing plant species at Boset District; (2) identifying major predictor variables that influence the prioritization and selection of species; and (3) develop a Generalized Linear Model (GLM) to predict the selection of species., Methods: A total of 96 informants comprising 59 men and 37 women between the ages of 18 and 81 were sampled. Data were collected using structured interviews, guided field walk, discussions and field observations., Results: Collected data indicated that 88.5% of the informants involved in firewood collection, while 90% practiced charcoal making. A total of 1533.60 Birr per household on average was earned annually from this activity. A total of 25 fuelwood producing plant species were identified and documented at Boset District. Of these, Acacia senegal, Acacia tortilis and Acacia robusta were the three best prioritized and selected indigenous high fuelwood producing species. Prosopis juliflora, Parthenium hysterophorus, Azadirachta indica, Calotropis procera, Cryptostegia grandiflora, Lantana camara and Senna occidentalis further grouped under introduced fuelwood species. Prediction of GLM assured sampled Kebeles and source of income generated from fuelwood species positively and significantly (p < 0.001) related to selection of species. Higher efficiency to provide energy and heat; little or no smoke or soot; easier to cut and split the wood and easier availability were some of the main selection criteria., Conclusions: This study provides valuable information in selecting and documenting of high fuelwood producing plant species for proper management and sustainable use at Boset District. The three most selected species (A. senegal, A. tortilis and A. robusta) should be further evaluated at laboratory to determine their calorific value and combustion characteristics., (© 2021. The Author(s).)

• This paper examined the financial viability of farmers' investment in acacia plantations in the Upper Blue Nile Basin. • The acacia-based taungya system has the potential to serve as an important developmental pathway out of poverty in Ethiopia. • In an Acacia-based plantation system, well endowed farmers are benefiting more compared to resource-poor counterparts. • In the early sales of plantation stands, in the first two years, the stand buyers got more returns than the growers. The use of tree-based fallowing as a sustainable land management system may serve as an important developmental pathway out of poverty across drought-prone watersheds in the Upper Blue Nile Basin, Ethiopia. This study employs a financial analysis technique, the computation of net present values, to explore the financial viability of farmers' investments in an intercropping farming system known as taungya. The analysis employs scenarios that include different farming systems, such as A. decurrens (J.C. Wendl.) Willd. cum teff (Eragrostis tef) intercropping, A. decurrens monocropping, and teff monocropping, as well as changes in output (charcoal and teff) prices and the discount rate. In addition, the time of sale is evaluated in terms of the distribution of profits between buyers and sellers and between sharecroppers and landowners. The intercropping practice (A. decurrens cum teff in the first year) tended to be more profitable than the alternative systems. Financially constrained farmers who have to sell their stands early, however, forego gains. Profits from stand sales later in the 5-year evaluation period were more equally shared between sellers and buyers. Sharecropping profits for farmers ranked among the lowest of the computed profits. A sensitivity analysis revealed that an increase in the discount rate tends to have a more detrimental effect than price fluctuations on the profitability of acacia-based taungya systems, although sharp price fluctuations could affect profitability and cause a farmer to shift back to an annual crop system. Despite their higher profitability, tree-based systems impose a risk of liquidity bottlenecks on farmers throughout the 5-year investment period, which implies that those who are endowed with land or who are more financially well-off can benefit from the required 5-year investment, but it may be more difficult for those who lack land or the necessary financial resources. Providing affordable financing for poorer and landless farmers could increase farmers' use of the taungya system and allow a more equitable distribution of benefits among the rural population. [ABSTRACT FROM AUTHOR]

Macropsis tincta Tisheсhkin sp. n., M. viridofulgida Tisheсhkin sp. n., M. nikippa Tisheсhkin sp. n., and M. antibia Tisheсhkin sp. n. from the vicinity of Ambo, Ethiopia are described. Redescriptions of M. simplex Jacobi, 1910, M. tuberculata (Linnavuori, 1978), and M. hippodameia Linnavuori, 1978 based on the material from Ambo are given. Apparently, Indian and African Acacia-dwelling Macropsis species represent a separate lineage evolved on Mimosoidea, and dispersed throughout subtropical and tropical regions of the Old World. Acacia-dwelling group of Macropsis demonstrate some morphological trends unknown in Palaearctic species; this makes it necessary to re-evaluate the diagnostic significance of some morphological traits for the taxonomy of Macropsini.

The consumption of meat may provide herbivorous animals with important nutrients that are scarce in their plant-based diet. Seasonal variation in plant food availability has been suggested to motivate dietary flexibility in a range of species and thus primates may seek more prey when key plant resources are unavailable. Alternatively, prey encounter rate may drive meat eating. Here we investigate patterns of meat eating in hamadryas baboons (Papio hamadryas) at Filoha, Awash National Park, Ethiopia. The Filoha baboons rely largely on doum palm fruit (Hyphaene thebaica), which are available most months of the year, and the young leaves of Acacia senegal, which are more abundant during the wet season. We hypothesized that the baboons would consume more meat when H. thebaica and A. senegal were less available, which we tested by comparing meat eating and consumption of these plant food species from March 2005 through February 2006. Our results reveal a high rate of vertebrate meat eating at Filoha (0.028/hour of observation) compared with other hamadryas sites. We found no relationship, however, between meat eating (either insect or vertebrate) and either rainfall or consumption of H. thebaica or A. senegal, indicating that availability of preferred plant resources does not drive meat consumption. Vertebrate consumption and time spent feeding were significantly negatively associated; there was no relationship, however, between the consumption of animal matter and either home range size or daily path length. Vertebrate and insect consumption alternated throughout the year such that the baboons maintained a small amount of animal matter in their diet year-round. Our results suggest that the baboons do not often actively seek animal matter, but consume it opportunistically, with the presence of locust and dragonfly swarms driving insect consumption, and both prey availability and the availability of feeding time shaping vertebrate predation., (© 2019 Wiley Periodicals, Inc.)

Background: Visceral leishmaniasis (VL), a vector-borne disease caused by species of the L.donovani complex, has (re)-emerged in Ethiopia during the last two decades and is currently of increasing public health concern. However, very little is known about VL epidemiology in the Somali Region of Ethiopia. The aim of this study was to provide detailed epidemiological information on seroprevalence, associated factors and incriminated vectors of VL in Shebelle Zone and Ethiopian Somali Region in general., Methods: A cross-sectional epidemiological study was conducted between March and May 2016 in Gode and Adadle districts of Shebelle Zone, Ethiopian Somali Region. Two-stage semi-random sampling was applied for selecting study participants for the field survey. The study included structured questionnaire interviews, serological assays (rK39-immunochromatographic test), ELISA and entomological surveys., Results: From a total of 361 participants, 57 (15.8%) were seropositive for VL including 46 (12.7%) rK39 positive and 11 (3.0%) positive by both rK39 and ELISA. VL seroprevalence was higher (P < 0.001) in Adadle (31.1%) compared to Gode (12.7%) district. The VL seroprevalence rate was higher in females than in males [rK39 (17.2 vs 14.0%) and ELISA (3.4 vs 2.5%)]. Children under the 15 years of age were the most highly affected group [rK39 (20.4%) and ELISA (4.4%)]. Increased VL risk was associated with presence of termite hills, study district, outdoor sleeping, Acacia trees and domestic animals [odds ratio (95% confidence interval): 12.58 (5.911-26.763), 5.40 (2.90-10.07), 5.31 (2.283-12.364), 2.37 (1.1190-4.728) and 0.199 (0.097-0.410), respectively]. The entomological survey identified 74 Phlebotomus [P. (Larroussius) orientalis (52/74), P. (Anaphlebotomus) rodhaini (14/74), P. (Paraphlebotomus) sergenti (8/74)] and 11 Sergentomyia sand flies. The average frequency of P. orientalis (3.06 ± 0.66) collected by all traps per night was higher than that of other species. The average frequency of total and specific (P. orientalis) female sand flies was higher in Adadle (1.89 ± 0.423 vs 1.11 ± 0.309) than in Gode (0.62 ± 0.324 vs 0.38 ± 0.183) district. The highest mean numbers of total (8 ± 1.5) and P. orientalis (6 ± 0.913) sand flies were collected in termite hills., Conclusions: The present findings revealed potential new VL-transmission foci in the study districts. Therefore, the need for parasitological and molecular characterization of the parasite in humans and vector sand flies is of paramount importance to confirm transmission.

The benefits of spatial memory for foraging animals can be assessed on two distinct spatial scales: small-scale space (travel within patches) and large-scale space (travel between patches). While the patches themselves may be distributed at low density, within patches resources are likely densely distributed. We propose, therefore, that spatial memory for recalling the particular locations of previously visited feeding sites will be more advantageous during between-patch movement, where it may reduce the distances traveled by animals that possess this ability compared to those that must rely on random search. We address this hypothesis by employing descriptive statistics and spectral analyses to characterize the daily foraging routes of a band of wild hamadryas baboons in Filoha, Ethiopia. The baboons slept on two main cliffs--the Filoha cliff and the Wasaro cliff--and daily travel began and ended on a cliff; thus four daily travel routes exist: Filoha-Filoha, Filoha-Wasaro, Wasaro-Wasaro, Wasaro-Filoha. We use newly developed partial sum methods and distribution-fitting analyses to distinguish periods of area-restricted search from more extensive movements. The results indicate a single peak in travel activity in the Filoha-Filoha and Wasaro-Filoha routes, three peaks of travel activity in the Filoha-Wasaro routes, and two peaks in the Wasaro-Wasaro routes; and are consistent with on-the-ground observations of foraging and ranging behavior of the baboons. In each of the four daily travel routes the "tipping points" identified by the partial sum analyses indicate transitions between travel in small- versus large-scale space. The correspondence between the quantitative analyses and the field observations suggest great utility for using these types of analyses to examine primate travel patterns and especially in distinguishing between movement in small versus large-scale space. Only the distribution-fitting analyses are inconsistent with the field observations, which may be due to the scale at which these analyses were conducted., (© 2013 Wiley Periodicals, Inc.)

Most hamadryas baboons rely on Acacia species for subsistence in their semidesert habitats. Unlike other hamadryas sites, palm forests at Filoha in Awash National Park, Ethiopia, provide the baboons with a preferred food resource close to a commonly used sleeping site. The baboons are expected to feed on doum palm trees when fruit is available, and this resource use should play a role in ranging patterns. This paper describes the feeding ecology, food availability and ranging patterns of a band of wild hamadryas baboons at Filoha from March 2005 to February 2006. Data on feeding and ranging behavior derive from band scans during all-day follows of baboons, and data on food availability derive from monthly phenological monitoring of frequently consumed food species. The baboons fed predominantly on palms when fruit was available, and preferred the flowers of Acacia senegal to its leaves. There was no relationship between daily path length and the proportion of palm fruit in the baboons' diet, but changes in the availability of fruit across the Filoha region appear to mirror the baboons' shifting use of its home range. The large band sizes at Filoha may obscure the effects doum palm fruit might have on ranging patterns., (Copyright © 2010 S. Karger AG, Basel.)

A 90-day growth trial was designed to compare the performance of calves on 3 dry-season diets composed of local resources from the Borana pastoral system. The control group received the traditional diet of cut-and-carry, standing-brown grass while the other diets consisted of grass hay stored since the previous wet season with or without Acacia tortilis fruits as a protein supplement. All calves had access to water once every 3 days as traditional. The objective was to see whether modest changes in traditional feeding management could enhance nutrient intake and growth of calves under conditions of restricted water access. The hay had a higher nitrogen content and in vitro digestibility than the standing grass, and the Acacia fruits had higher nutrient concentrations than the hay (both at P < or = 0.05). Calves on hay plus Acacia fruits had higher nitrogen intakes than those on hay only, and those on hay only had higher nitrogen intakes than those on standing grass (both at P < or = 0.05). Calves on standing grass lost weight and condition, those on hay only maintained weight but lost condition, and those on hay plus Acacia fruits gained weight and maintained condition (all at P < or = 0.05). Calves consumed the most feed on day 2 of the watering cycle, regardless of treatment. Water intake increased 27% for animals on both hay diets compared to those on standing grass (P < or = 0.01). Feeding packages based on hay making and collection of browse legumes are appropriate options for extension to these semi-settled pastoralists.