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This study assesses the diversity, composition, structure and abundance of urban forests in Adama city, Central Ethiopia to provide baseline information useful for developing a conservation strategy. The urban forest of Adama has an estimated 525,200 trees with a tree cover of 20%. The three most common species are Azadirachta Indica (14.8%), Carica papaya (6.8%), and Acacia abyssinica (5%). The i-Tree Eco model was used to organise output. A total of 214 sample plots were generated directly in the i-Tree Eco application using the random plots' generator via the Google Maps function. A 0.1acre circular plot was used. A total of 805 trees were sampled across the 214 plots. Among the 86 species encountered in the sample plots, 68 (79%) were introduced and only 18 (21%) were native species. Most introduced trees originated from Asia (22%). The tree diversity calculated using the Shannon Weiner index (H') was 3.61 and the dominance of Simpson's value was 0.95. The evenness index of the plots sampled was 0.80. The study indicates the crucial role that urban forests play in maintaining and conserving urban trees and enhancing ecosystem services in urban areas. [ABSTRACT FROM AUTHOR]

Land degradation in the form of soil and vegetation decline has been an ecological and agricultural problem in Ethiopian highlands. To overcome this issue, the government and local community has been practised area exclosure across the country including Amelake sub-watershed, southern Ethiopia. This study aimed to evaluate area exclosure effects on soil basic properties and woody species diversity in Amaleke sub-watershed. Composite soil samples and Woody plant species were collected with the transects by systematic sampling plot design technique from area exclosure for 10 years and adjacent degraded land with similar landscape position. The collected soil samples from area exclosure and degraded land were analysed through ANOVA whereas woody plant species determined by Shannon diversity. The result revealed that area exclosure had significantly (P < 0.05) different values for all basic soil properties except for soil bulk density, sand, EC and pH. Whereas 16 woody species representing 12 families were recorded in the study site. Out of the 12 families, all were recorded in the exclosure while 5 were recorded in the degraded site. Diversity index result revealed that the woody plant species diversity in exclosure and adjacent degraded land were 1.41 and 1.1, respectively. Similarly, species evenness in exclosure and degraded site were 2.41 and 1.84, respectively, whereas species richness in area exclosure and degraded land was 15 and 6, respectively. In general, exclosure has a great contribution to maintain health soil environment and woody plant species in the study area. Therefore, to improve the soil basic properties and woody species diversity area exclosure practices will be expanded to other degraded watersheds. [ABSTRACT FROM AUTHOR]

Leucaena leucocephala is worldwide used for wood production, reforestation and for feeding livestock. To assess the potential use of leucaena for animal nutrition, we analysed the composition of methanolic extracts of leaf samples of two varieties occurring in Sicily (Mediterranean area), also determining the presence of mimosine. [ABSTRACT FROM AUTHOR]

Numerous reports describe the antioxidant and antimicrobial activity of polyphenols-rich plant extracts. The aim of this study was to determine the total polyphenols content (TPC), and the in vitro (DPPH, FRAP and TEAC) antioxidant and antibacterial activity of leaves and wood of six native woody species (Aspidosperma quebracho-blanct, Sarcomphalus mistol, Geoffroea decorticans, Prosopis chilensis, Larrea divaricata and Larrea cuneifolia) from Catamarca. Also, the phenolic profile was determined in the species with higher activity. L. cuneifolia leaf extracts showed the highest antioxidant activity followed by L. divaricata and S. mistol, while S. mistol wood extracts showed the highest. Furthermore, Larrea species showed antibacterial activity against S. aureus and E. faecalis strains showing cidal effects mainly against S. aureus. Fifty-nine polyphenols were identified in leaves and wood of Larrea and S. mistol species, which are likely to be responsible for the different activities observed. [ABSTRACT FROM AUTHOR]

Plant species selection is an important criterion for improving treatment wetland performance. The aim of this work was to evaluate removal efficiency and potential uses of woody species in treatment wetlands during the establishment year. Plant development, removal efficiency and evapotranspiration rate of five woody species (Salix interior, Salix miyabeana, Sambucus canadensis, Myrica gale, Acer saccharinum) and four herbaceous taxa typically used in treatment wetlands (Typha angustifolia, Phragmites australis australis, Phragmites australis americanus, Phalaris arundinacea) were compared in a mesocosm-scale study during one growing season. Woody species showed significantly slower growth, but displayed several characteristics of interest for treatment wetland applications: good adaptation to wetlands conditions; high organic matter removal (76–88%); high nutrient accumulation in tissues and high evapotranspiration capacity. During the establishment year, herbaceous species showed greater biomass development (above- and belowground parts), higher evapotranspiration rate (>3.84 L m−2 d−1 compared to <3.23 L m−2 d−1 for woody species) and overall pollutant removal efficiency. These characteristics confirm the high efficiency of treatment wetlands planted with herbaceous species even in the first growing season. However, given their greater potential biomass development, woody species could represent an excellent alternative for improving treatment wetlands long-term performance. [ABSTRACT FROM AUTHOR]

Woody species, especially dinitrogen-fixing species, can provide multiple products including food, fuelwood and fodder. In cut-and-carry silvopastoral systems, woody trees are often severely pruned for harvesting nitrogen (N)-rich fodder. However, very few studies have assessed the influence of this management practice on symbiotic N2 fixation. The study was conducted at Fountainhill Estate, Wartburg, South Africa, to assess the influence of pruning height on N2 fixation of pigeon pea (Cajanus cajan) using the 15N natural abundance method. Pigeon pea was grown in association with Panicum maximum. The treatments were unpruned, and pruning at 60 or 90 cm height. Results showed that pruning at 60 cm height significantly decreased total N (P ≤ 0.05), percentage of N derived from atmospheric N2 (P ≤ 0.05) and amount of N2 fixed (P ≤ 0.05) compared with unpruned plants and those pruned at 90 cm height. It was concluded that harvesting fodder at 90 cm height should be practised for pigeon pea to optimise symbiotic N2 fixation. [ABSTRACT FROM AUTHOR]

We investigated the composition of tropical dry forest woody species at adult, sapling, and seedling stages, in terms of plant diversity, distribution, and importance value index (IVI), and identified the dominant and ubiquitous species in the five study sites having variable edaphic properties. Species varied markedly in the composition and IVI at different sites. The semi-evergreen species,Shorea robusta, was dominant at the wettest site at all the three growth stages; at the driest site, highly deciduous speciesLannea coromandelicawas the dominant adult species andNyctanthis arbortrististhe dominant sapling and seedling species. Soil moisture content (SMC) altered the distribution of about 8% of the adult species. ANOVA indicated significant site-wise differences in the Shannon-Wiener index, Whittaker’s evenness, Margalef’s species richness, and β-diversity for the woody species at all the three stages. The Shannon-Wiener index, Whittaker’s evenness, Margalef’s species richness, and β-diversity were greater in seedlings as compared to adult and saplings of tree species. These variations in species composition and distribution are evidently on account of different levels of SMC as well as habitat heterogeneity as indicated by β-diversity which was independent of SMC. [ABSTRACT FROM AUTHOR]

We studied selected leaf traits [leaf area (LA), leaf water content (LWC), leaf fresh weight (LFW), leaf dry weight (LDW), specific leaf area (SLA) and chlorophyll content] of eight woody species (Shorea robusta,Buchanania lanzan,Diospyros melanoxylon,Lagerstroemia parviflora,Lannea coromandelica,Terminalia tomentosa,Holarrhena antidysentericaandLantana camara) dominant at four sites in a dry tropical deciduous forest over complete two annual cycles (2008–2010). Our results showed that leaf traits varied across species (1.7–11.5 fold), months (1.2–1.5 fold) and sites (1.1–1.3 fold). However, leaf traits showed smaller variation between sites than between species. Leaf lifespan varied from 7 months (L. coromandelica) to 12 months (S. robusta). On the same sites, species differed in the length of deciduous period. The maximum LA, LDW, LFW and LWC were recorded for the semi-evergreen species, SLA for long-deciduous species and chlorophyll content for short-deciduous species, respectively. The coefficient of variation was maximum for LDW and minimum for chlorophyll content. Among the eight woody species,T. tomentosaexhibited the greatest LA, LDW, LFW and LWC. LA, LWC, LFW, LDW, SLA, LD, SD, MD & SE confirm. [ABSTRACT FROM PUBLISHER]

Litter decay is a significant part of carbon budget. Due to strong environmental control, the changes in the environment may drastically influence the litter decay rates. Litter decomposition of eight dry tropical woody species, viz.Shorea robusta,Buchanania lanzan,Diospyros melanoxylon,Lagerstroemia parviflora,Lannea coromandelica,Terminalia tomentosa,Holarrhena antidysentericaandLantana camarawas studied to document the effect of intra-annual changes in the environment. Litter decomposition was monitored at monthly intervals at five sites using litter bag technique over an annual cycle in a dry tropical deciduous forest of Vindhyan highland, India. Weight loss differed among species and through months, and ranged from 15.38% inL. camaraat Kotwa site in January to 30.72% inT. tomentosaat Hathinala site in August. Peak weight loss occurred in August and averaged 46.2% across species and sites. Nitrogen and phosphorus mineralization rates also varied significantly from species to species.T. tomentosahaving higher nitrogen content and lowerC/Nratio than other species exhibited faster weight loss. Nitrogen and phosphorus contents of litter showed significant positive correlation with weight loss.C/Nratio was negatively related to decay constant, and the weight loss was positively related to the soil surface temperature as well as soil moisture content. [ABSTRACT FROM AUTHOR]

Both local and regional predictors play a role in determining plant community structure and composition. Climate, soil features as well as different local history and management affect forest understorey and tree species composition, but to date their specific role is relatively unknown. Few studies have addressed the importance of these predictors, especially in the Mediterranean area, where environmental conditions and human impacts have generated heterogeneous forest communities. In this study, the relationships between environmental variables and species richness of different groups of vascular plants (vascular species, woody species and open habitat species) and bryophytes were investigated in Tuscan forests. A total of 37 environmental variables were used by generalised linear model fitting in order to find parsimonious sub-sets of environmental factors (predictors) that are able to explain species diversity patterns at the local scale. Moreover, the role of regional and local variable groups on species richness of the considered plant groups was estimated by using the variance partitioning approach. We found that local variables, such as forest management and structure, explained more variance than regional variables for total species richness, open habitat species richness and bryophyte species richness. On the other hand, regional variables (such as elevation) played a central role for woody species richness. [ABSTRACT FROM AUTHOR]

Near-infrared reflectance spectroscopy (NIRS) was evaluated for its effectiveness to determine ash and mineral concentrations [potassium (K), magnesium (Mg), copper (Cu), iron (Fe), and zinc (Zn)], in a total of 182 leaf samples of 17 woody species located in the central-western region of the Iberian Peninsula. Chemical analysis revealed great variability in all leaf mineral elements. This variability was mainly related to differences in leaf habit (deciduous versus evergreen) and to differences in mean leaf longevity and among leaf age classes within evergreen species. A set of samples including all 17 species and leaf age classes was used to develop the calibration equations using multiple linear regression (MLR) and partial-least squares regression (PLSR). The set of samples that did not enter in the calibration was used for external validation. In general, the most satisfactory results were obtained using PLSR and derivative transformations. Despite the strong heterogeneity of the samples included in the study, the results showed that NIRS can be employed as an effective tool, alternative to the more time-consuming standard methods. The best predictive model was obtained for ash content. Models with acceptable accuracy were obtained in the prediction of K and Mg contents. However, their applicability for the determination of trace elements was more limited. [ABSTRACT FROM AUTHOR]