Unlike in the developed countries, Ethiopia does not have carbon inventories and databank to monitor and enhance carbon sequestration potential of different forests. Only small efforts have been made so far to assess the biomass and soil carbon sequestration at micro-level. This study was carried out to obtain sufficient information about the carbon stock potential of Gerba-Dima forest in south-western Ethiopia. A total of 90 sample plots were laid by employing stratified random sampling. Nested plots were used to collect data of the four carbon pools. For trees with a diameter range of 5 cm < diameter < 20 cm, the carbon stock was assessed from a plot size of 49 m2 (7 m * 7 m). For trees with a diameter range of 20 cm < diameter < 50 cm, the carbon stock was assessed from a plot size of 625 m2 (25 m * 25 m). For trees > 50 cm diameter, an additional larger sample of 35 * 35 m2 was used. Litter, herb and soil data were collected from 1 m2 subplot established at the center of each nested plot. To compute the above ground biomass carbon stock of trees and shrubs with DBH > 5 cm, their DBH and height were measured. The biomass carbon assessment of woody species having DBH < 5 cm, litter and herb were conducted by measuring their fresh weight in the field and dry weight in the laboratory. The mean total carbon stock density of Gerba-Dima forest was found to be 508.9 tons carbon ha−1, out of which 243.8, 45.97, 0.03 and 219.1 tons carbon ha−1 were stored in the above ground biomass, below ground biomass, litter biomass and soil organic carbon, respectively. The existence of high carbon stock in the study forest shows the potential of the area for climate change mitigation. Thus, all stakeholders at the local and national level should work together to implement effective conservation measures and get benefit from the biocarbon fund.

Background: This study was carried out in Gerba Dima Forest, South-Western Ethiopia, to determine the floristic composition, species diversity and community types along environmental gradients. Identifying and interpreting the structure of species assemblages is the main goal of plant community ecology. Investigation of forest community composition and structure is very useful in understanding the status of tree population, regeneration, and diversity for conservation purposes. Method: Ninety sample plots having a size of 25 × 25 m (625 m²) were laid by employing stratified random sampling. Nested plots were used to sample plants of different sizes and different environmental variables. All woody plant species with Diameter at breast height (DBH) ≥ 2.5 cm and height ≥ 1.5 m were recorded in 25 m × 25 m plots. Hierarchical (agglomerative) cluster analysis was performed using the free statistical software R version 3.6.1 using package cluster to classify the vegetation into plant community types. Redundancy Analysis (RDA) ordination was used in describing the pattern of plant communities along an environmental gradient. Result: One hundred and eighty plant species belonging to 145 genera, 69 families and comprising of 15 endemic species were recorded. Of these, 52 species (28.9%) were trees, 6 species (3.33%) were Trees/shrubs, 31 species (17.22%) were shrubs, 76 species (42.22%) were herbs, and 15 species (8.33%) were Lianas. Rubiaceae, Acanthaceae and Asteraceae were the richest family each represented by 11 genera and 11 species (6.11%), 9 genera and 11 species (6.11%), 6 genera and 11 species (6.11%), respectively of total floristic composition. Cluster analysis resulted in five different plant communities and this result was supported by the ordination result. RDA result showed altitude was the main environmental variable in determining the plant communities. The ANOVA test indicated that the five community types differ significantly from each other with regard to Electrical Conductivity and Potassium. Conclusions: Description of floristic diversity of species in Gerba Dima forest revealed the presence of high species diversity and richness. The presence of endemic plant species in the study forest shows the potential of the area for biodiversity conservation.

Understanding the impact of drought stress on Arabica coffee physiology and metabolism is essential in the pursuit of developing drought-resistant varieties. In this study, we explored the physiological and metabolite changes in coffee genotypes exhibiting varying degrees of tolerance to drought—namely, the relatively tolerant Ca74110 and Ca74112, and the sensitive Ca754 and CaJ-19 genotypes—under well-watered conditions and during terminal drought stress periods at two time points (0 and 60 days following the onset of stress). The metabolite profiling uncovered significant associations between the growth and the physiological characteristics of coffee genotypes with distinct drought tolerance behaviors. Initially, no marked differences were observed among the genotypes or treatments. However, at the 60-day post-drought onset time point, notably higher shoot growth, biomass, CO₂ assimilation, pigments, and various physiological parameters were evident, particularly in the relatively tolerant genotypes. The metabolite profiling revealed elevations in glucose, maltose, amino acids, and organic acids, and decreases in other metabolites. These alterations were more pronounced in the drought-tolerant genotypes, indicating a correlation between enhanced compatible solutes and energy-associated metabolites crucial for drought tolerance mechanisms. This research introduces GC-MS-based metabolome profiling to the study of Ethiopian coffee, shedding light on its intricate responses to drought stress and paving the way for the potential development of drought-resistant coffee seedlings in intensified agro-ecological zones.

The study was conducted in Kafta Sheraro National Park (KSNP) dry woodland natural forest located in Kafta Humera and Tahitay Adiyabo weredas (districts), Western and Northwestern Zones of Tigray regional governmental state, North Ethiopia. The objective of the study was to explore the floristic composition, structure, and regeneration of woody species in the home ofLoxodonta africanaL.,Hippotragus equinus,Anthropoides virgo,Ourebia ourebi,Crocuta crocuta,Tragelaphus strepsiceros,Phacochoerus africanus, and unidentified crocodile and fish species. In the park, the vegetation ecology has not been studied up to date which is necessary for conservation. The systematic sampling technique was used to collect vegetation and human disturbance (presence and absence) data from August to December 2018. The vegetation data were collected from 161 plots each with a size of 400 m²(20 m × 20 m) for tree/shrub while subplots of size 100 m²(10 m × 10 m) and 25 m²(5 m × 5 m) for sapling and seedling, respectively, were established in the main plots. Individual tree and shrub diameter at breast height (DBH) ≥2.5 cm and height ≥ 2 m were measured using tape meter and clinometer, respectively. Diameter at breast height (DBH), frequency, density, basal area, and importance value index (IVI) were used for vegetation structure description while the density of mature trees, sapling, and seedling was used for regeneration. A total of 70 woody species (46 (65.7%) trees, 18 (25.7%) shrubs, and 6 (8.6%) tree/shrub) were identified. The total basal area and density of 79.3 ± 4.6 m²·ha⁻¹and 466 ± 12.8 stems·ha⁻¹, respectively, were calculated for 64 woody species. Fabaceae was the most dominant family with 16 species (22.9%) followed by Combretaceae with 8 species (11.4%). The most dominant and frequent species throughout the park wereAcacia mellifera,Combretum hartmannianum,Terminalia brownii,Balanites aegyptiaca,Dichrostachys cinerea,Acacia senegal,Acacia oerfota,Boswellia papyrifera, Ziziphus spina-christi, andAnogeissus leiocarpus. Abnormal patterns of selected woody species were dominantly identified. The regenerating status of all the woody plant species was categorized as “fair” (18.75%), “poor” (7.81%), and “none” (73.44%). There was a significant correlation between altitude, anthropogenic disturbance (grazing and fire frequency), and density of seedling, sapling, and mature trees. But there was no correlation between gold mining and regeneration population. However, there is a good initiation for the conservation of the park; still, the vegetation of the park was threatened by human-induced fire following intensive farming, gold mining, and overgrazing. Therefore, the study area was the habitat for the population of the African elephant; species with low importance value indices and lack or having few seedling and sapling stage should be prioritized for conservation, and their soil seed banks should be studied further.