The impact of ungulate browsing on tree saplings has been found to have a negative effect on the regeneration of temperate forests. However, it remains ambiguous whether a relationship exists between ...browsing intensity and soil quality in natural forests. Therefore, we conducted a study in Roztoczańskie National Park to investigate the relationship between soil quality and browsing intensity for tree saplings. The aim was to gain a better understanding of how soil quality affects the browsing of ungulates on tree species. Baseline data (sapling height, basal diameter, crown length and width, browsed-shoot diameter, and soil samples) were collected from the 22 belt transects established in the permanent research plots. The soil quality index was calculated using physical and chemical soil properties. Twig dry mass was determined using allometric equations. Species relative density and browsing intensity were assessed through field measurements. Relationships between the variables were established using a linear regression model. The results suggest that browsing intensity is influenced by the gradient of the soil quality index and that it varies between tree species. Along the increasing soil quality gradient, tree species’ relative density (p = 0.012) and twig dry mass m−2 (p = 0.005) significantly decreased for A. pseudoplatanus. In contrast, browsing intensity increased significantly with an increasing species relative density for A. pseudoplatanus (p = 0.00) and C. betulus (p = 0.001) and with an increasing twig dry mass for F. sylvatica (p = 0.034) and C. betulus (p = 0.004). Browsing intensity increased significantly with an increasing soil quality index for F. sylvatica (p = 0.027) and decreased significantly for A. pseudoplatanus (p = 0.036). Notably, there was a significant positive relationship between browsing intensity and species relative density and twig dry mass, indicating that ungulate browsing is concentrated where browsing is abundant. These results provide insights that can be used to improve management and conservation strategies to protect tree species vulnerable to ungulate herbivory.
•Topography and climatic circumstances are responsible for Ethiopia's diverse vegetation, which ranges from the Afro-alpine in the mountains to arid and semi-arid vegetation types in the lowlands.•In ...Ethiopia, the Shannon-Winner diversity index (H') of woody species aligns with the usual Shannon-Weiner diversity index (H') range.•Land use changes and domestic animals are impeding the natural regeneration of woody species.•Is the natural regeneration of woody species in forest plantations determined by plantation forest species selection, distance from natural forest, or plantation forest silvicultural management? There are inconsistencies in the country's existing state of knowledge in this area.
The goal of this study was to elucidate the research gap on woody species diversity and regeneration in Ethiopian natural and managed forests. Ethiopia is a biodiversity hotspot in the Horn of Africa, having a large variety of indigenous woody species. Ecological variability, population increase, and climate change-related disturbances have all had an impact on the variety and regeneration of woody species across various gradients in the country. Nonetheless, extant evidence for woody species in natural and managed forests suggests that Ethiopia's Shannon diversity index (H') and evenness index (E) are equivalent to those seen in several tropical countries. There is a big knowledge vacuum when it comes to explaining the relationship between regeneration issues and the recruitment of woody species. Different studies have found contradictory results, implying that more research is needed before using the information for better woody species diversity and regeneration enhancement projects. To minimize inconsistencies in management suggestions, it's necessary to fill this knowledge gap by considering ecological diversity, land use history, forest types and species composition, as well as evolutionary processes.
•The soil chemical properties are significantly better within the canopy of the agroforestry species.•The effects of agroforestry species on soil chemical properties are species-specific.•The ...elevation gradient does not affect the role of agroforestry species on most soil chemical properties.•Cassava (Manihot esculenta) within the agroforestry system can lead to unsustainable soil properties.
Native trees in agroforestry systems sustain soil properties by building up and recycling nutrients in a sustainable manner. This manuscript aimed to assess the impact of different agroforestry species on soil chemical properties. Soil samples were collected from within and outside the canopy zones of native tree species (Cordia africana, Ficus sur) and a perennial tuber crop (Manihot esculenta) in agroforestry systems at three different elevations. The results showed that, the soil chemical properties were significantly better within the canopy zones of all agroforestry species compared to outside. However, there was insignificant difference in pH between the soil inside and outside the canopy of Manihot esculenta. With a few exceptions, the evaluated soil chemical parameters exhibited minimal variations between Cordia africana and Ficus sur. Interestingly, Manihot esculenta had the least positive impact on soil chemical properties in the agroforestry system, indicating that native tree species enhance soil chemical properties more effectively than the tuber crop. The influence of agroforestry species on soil chemical properties remained consistent across all elevation ranges, suggesting that elevation does not alter the effects of agroforestry species on soil properties. In general, native trees, Cordia africana, and Ficus sur, positively contribute to soil chemical properties, while Manihot esculenta has a negative impact, particularly on cation exchange capacity, soil pH, and available potassium in comparison to the native tree species. These findings highlight the importance of using native tree species in agroforestry systems to promote healthy soil chemical properties and enhance the resilience of forest ecosystems.
Knowledge of the quantity of twig dry mass (available fodder) of saplings is crucial for understanding tree recruitment under wild ungulate browsing pressure in forest ecosystems. Therefore, this ...study aimed to develop allometric equations for estimating twig dry mass using sapling structural data and to model the twig dry mass of saplings of various species in various size classes while quantitatively describing the variations among tree species. Sapling biomass samples were taken for six widely spread tree species in two national parks in Poland. After drying the biomass samples in the oven for 72 h at 65 °C, the data were analyzed, and models were generated using the ordinary least squares and generalized additive methods. The results confirmed our hypothesis that different tree species differ in their allometric properties. The twig dry masses of Acer pseudoplatanus and Carpinus betulus were best estimated by basal diameter, whereas those of Picea abies, Abies alba, and Fagus sylvatica were best estimated by sapling height. In contrast, the model quality for Fagus sylvatica and Sorbus aucuparia was enhanced by combining the sapling height with the mean largest crown length (MLCL). For all species, the twig dry mass distribution was linear along sapling height classes and exponentially increased with shoot diameter classes, with coniferous species exhibiting the highest correlation. On the other hand, the proportion of twig dry mass to total sapling dry mass followed the order S. aucuparia > A. alba > P. abies > F. sylvatica > C. betulus > A. pseudoplatanus. The developed allometric equations contribute significantly to the already available collection of published biomass equations. Moreover, they extremely useful in estimating the browsing potential of tree saplings falling within size ranges conducive to herbivore browsing.
This study aims to compare the proportion of macronutrients in different parts of the aboveground biomass; and to estimate the amount of macronutrient loss from continuous farmlands (mechanized farm ...and traditional farm) and plantation stands (Cupresus lusitanica and Eucalyptus saligna) through harvesting. From 20 × 20 m2 sized sample plots, a representative samples were collected from leaf, branch and stem of the plantation stands. Macronutrient analyses were carried out for the samples taken from plantations and maize crops on continuous farmlands. All data collected were subjected to ANOVA using the general linear model of SAS 9.0 at P < 0.05. The results of macronutrient in aboveground biomass of maize in the continuous farm lands shows that, the grain component contained as much as 50% of N and 60% of P compared to leaf and stem. However, a high proportion of K, Ca, and Mg were found in the leaf and stem components. In the case of C. lusitanica, 64.4% N, 70% P, 68.4% K, 65.3% Ca, and 68.75% of Mg was found in the stem compared to the leaf and branch. In the E. saligna, the stem contained 22% N, 30% P, 11.8% K, 26.6% Ca, and 12.5% Mg; with the remaining proportion of each nutrient found in the leaf and branch. Based on the results, much of the nutrients can be removed through the leaf and stem removal in the continuous farmlands. Complete removal of the biomass with little residue returned to the soil, for long periods under plantation land use, may also lead to macronutrient depletion. Therefore, to minimize this effect, the aboveground biomass harvest should focus on grain only on the farmlands, and stem only on the plantations.
Total harvest of the biomass in the continues farmlands, would result in loss of macronutrients. Total removal of the aboveground biomass under tree plantation stands may also result in the loss of soil macronutrients, which in turn result in land degradation. Especially, the leaves of the plantation trees contain higher concentration of macronutrients, and returning this part will lead to land restoration and soil macronutrient improvement.
The study was conducted in five administrative zones of the Ethiopian Somali Regional State, with the objectives of characterizing the major camel browse and grazed plant species and their seasonal ...availability in pastoral and agro-pastoral areas. A semi-structured questionnaire, group discussions, field observations, and key informant interviews were used as the primary data collection tools, while different secondary data sources were also used. A total of 150 household heads were selected purposively for formal interview. The results showed that most (90.7%) of the respondents were male and 85.3% of the sampled households were illiterate. It was revealed that browsing trees and shrubs were the major camel feed resources in pastoral and agro-pastoral areas. Although the quality and quantity of camel feed vary in dry (66%) and wet (88%) seasons; trees and shrubs were the major feed resources at all seasons, while the herbaceous species cover only 34% in both pastoral and agro-pastoral areas. The identified camel feed species in the study districts comprise 38 tree species, 20 herbaceous species, 12 shrub, 7 bush, and 17 grass species. The study revealed that there is a need to raise awareness among the pastoralist and agro-pastoral communities on the importance of browse plant species management and sustainable utilization.
Forest is one of the vital resources that determine the livelihood, environmental stability, and societal development. Duguna Fango is biologically diverse and deeply threatened in the region. The ...area has undergone extensive environmental changes since 1980s due to shifting cultivation, deforestation, urbanization, growing human population and drought. Thus, this research was conducted to investigate the status of forest change and degradation by using available satellite imageries at Duguna Fango Woreda. It was based on the corrected optical satellite data (Landsat 7 ETM of 2000, 2009, and Landsat 8 OLI/TIRS of 2018); available from the Global Land Cover Facility acquired in the drier seasons of the years was used for forest cover change analysis. Besides, normalized difference vegetation index (NDVI) indicators like (NDVI minimum, maximum, mean, and standard deviation) were also computed for the year 2000, 2009 and 2018 to determine the density of vegetation. The results showed in the period between 2000 and 2018, built up and cultivated lands increased with a mean annual rate of 92.18 and 366.96 ha/year, respectively. Followed by the reduction in dense forest with the mean annual rate of −228.27 ha/year. The NDVI minimum value showed a slight reduction from −0.09 in the year 2009 to −0.11 in the year 2018. The mean values are also decreased from 0.29 in 2009 to 0.16 in 2018. As indicated in the result of NDVI value, despite there is restoration, vegetation cover in general was reduced and the forests in particular were depleted from time to time.
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