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Background and Aims: The reliance on external support by lianas has been hypothesized to imply a reduction in the biomass cost of stem construction and root anchorage, and an increased investment in leaves, relative to self-supporting plants. These evolutionary trade-offs have not been adequately tested in an ontogenetic context and on the whole-plant scale. Moreover, the hypothesis may be extended to other potentially limiting resources, such as nitrogen (N.)., Methods: Plants belonging to five con-familiar pairs of temperate liana/shrub species were cultivated in 120 L barrels and sequentially harvested over up to three growing seasons. To account for the ontogenetic drift, organ biomass and nitrogen fractions were adjusted for plant biomass and N pool, respectively., Key Results: Lianas invested, on average, relatively less biomass in the root fraction in comparison with shrubs. This was offset by only insignificant increases in leaf or stem investment. Even though liana stems and roots showed higher N concentration in comparison with shrubs, plant N distribution was mostly driven by, and largely matched, the pattern of biomass distribution. Lianas also showed a greater relative growth rate than shrubs. The differences between the growth forms became apparent only when ontogenetic drift was controlled for. These results were confirmed regardless of whether reproductive biomass was included in the analysis., Conclusions: Our results suggest that temperate lianas, in spite of their diverse, species-specific resource distribution patterns, preferentially allocate resources to above-ground organs at the expense of roots. By identifying this trade-off and demonstrating the lack of a general trend for reduction in stem investment in lianas, we significantly modify the prevailing view of liana allocation strategies and evolutionary advantages. Such a resource distribution pattern, along with the cheap unit leaf area and stem unit length construction, situates lianas as a group close to the fast acquisition/rapid growth end of the life strategy spectrum., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Accurate ground-based estimation of the carbon stored in terrestrial ecosystems is critical to quantifying the global carbon budget. Allometric models provide cost-effective methods for biomass prediction. But do such models vary with ecoregion or plant functional type? We compiled 15 054 measurements of individual tree or shrub biomass from across Australia to examine the generality of allometric models for above-ground biomass prediction. This provided a robust case study because Australia includes ecoregions ranging from arid shrublands to tropical rainforests, and has a rich history of biomass research, particularly in planted forests. Regardless of ecoregion, for five broad categories of plant functional type (shrubs; multistemmed trees; trees of the genus Eucalyptus and closely related genera; other trees of high wood density; and other trees of low wood density), relationships between biomass and stem diameter were generic. Simple power-law models explained 84-95% of the variation in biomass, with little improvement in model performance when other plant variables (height, bole wood density), or site characteristics (climate, age, management) were included. Predictions of stand-based biomass from allometric models of varying levels of generalization (species-specific, plant functional type) were validated using whole-plot harvest data from 17 contrasting stands (range: 9-356 Mg ha(-1) ). Losses in efficiency of prediction were <1% if generalized models were used in place of species-specific models. Furthermore, application of generalized multispecies models did not introduce significant bias in biomass prediction in 92% of the 53 species tested. Further, overall efficiency of stand-level biomass prediction was 99%, with a mean absolute prediction error of only 13%. Hence, for cost-effective prediction of biomass across a wide range of stands, we recommend use of generic allometric models based on plant functional types. Development of new species-specific models is only warranted when gains in accuracy of stand-based predictions are relatively high (e.g. high-value monocultures)., (© 2015 John Wiley & Sons Ltd.)

Background and Aims: Climate change is advancing the leaf-out times of many plant species and mostly extending the growing season in temperate ecosystems. Laboratory experiments using twig cuttings from woody plant species present an affordable, easily replicated approach to investigate the relative importance of factors such as winter chilling, photoperiod, spring warming and frost tolerance on the leafing-out times of plant communities. This Viewpoint article demonstrates how the results of these experiments deepen our understanding beyond what is possible via analyses of remote sensing and field observation data, and can be used to improve climate change forecasts of shifts in phenology, ecosystem processes and ecological interactions., Scope: The twig method involves cutting dormant twigs from trees, shrubs and vines on a single date or at intervals over the course of the winter and early spring, placing them in containers of water in controlled environments, and regularly recording leaf-out, flowering or other phenomena. Prior to or following leaf-out or flowering, twigs may be assigned to treatment groups for experiments involving temperature, photoperiod, frost, humidity and more. Recent studies using these methods have shown that winter chilling requirements and spring warming strongly affect leaf-out and flowering times of temperate trees and shrubs, whereas photoperiod requirements are less important than previously thought for most species. Invasive plant species have weaker winter chilling requirements than native species in temperate ecosystems, and species that leaf-out early in the season have greater frost tolerance than later leafing species., Conclusions: This methodology could be extended to investigate additional drivers of leaf-out phenology, leaf senescence in the autumn, and other phenomena, and could be a useful tool for education and outreach. Additional ecosystems, such as boreal, southern hemisphere and sub-tropical forests, could also be investigated using dormant twigs to determine the drivers of leaf-out times and how these ecosystems will be affected by climate change., (© The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background and Aims: Autumn leaf senescence marks the end of the growing season in temperate ecosystems. Its timing influences a number of ecosystem processes, including carbon, water and nutrient cycling. Climate change is altering leaf senescence phenology and, as those changes continue, it will affect individual woody plants, species and ecosystems. In contrast to spring leaf out times, however, leaf senescence times remain relatively understudied. Variation in the phenology of leaf senescence among species and locations is still poorly understood., Methods: Leaf senescence phenology of 1360 deciduous plant species at six temperate botanical gardens in Asia, North America and Europe was recorded in 2012 and 2013. This large data set was used to explore ecological and phylogenetic factors associated with variation in leaf senescence., Key Results: Leaf senescence dates among species varied by 3 months on average across the six locations. Plant species tended to undergo leaf senescence in the same order in the autumns of both years at each location, but the order of senescence was only weakly correlated across sites. Leaf senescence times were not related to spring leaf out times, were not evolutionarily conserved and were only minimally influenced by growth habit, wood anatomy and percentage colour change or leaf drop. These weak patterns of leaf senescence timing contrast with much stronger leaf out patterns from a previous study., Conclusions: The results suggest that, in contrast to the broader temperature effects that determine leaf out times, leaf senescence times are probably determined by a larger or different suite of local environmental effects, including temperature, soil moisture, frost and wind. Determining the importance of these factors for a wide range of species represents the next challenge for understanding how climate change is affecting the end of the growing season and associated ecosystem processes., (© The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Leaf out phenology affects a wide variety of ecosystem processes and ecological interactions and will take on added significance as leaf out times increasingly shift in response to warming temperatures associated with climate change. There is, however, relatively little information available on the factors affecting species differences in leaf out phenology. An international team of researchers from eight Northern Hemisphere temperate botanical gardens recorded leaf out dates of c. 1600 woody species in 2011 and 2012. Leaf out dates in woody species differed by as much as 3 months at a single site and exhibited strong phylogenetic and anatomical relationships. On average, angiosperms leafed out earlier than gymnosperms, deciduous species earlier than evergreen species, shrubs earlier than trees, diffuse and semi-ring porous species earlier than ring porous species, and species with smaller diameter xylem vessels earlier than species with larger diameter vessels. The order of species leaf out was generally consistent between years and among sites. As species distribution and abundance shift due to climate change, interspecific differences in leaf out phenology may affect ecosystem processes such as carbon, water, and nutrient cycling. Our open access leaf out data provide a critical framework for monitoring and modelling such changes going forward., (© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.)

Background. The issue of the use of hydrophilic polymers in forestry in the arid conditions of the Volgograd region has been little studied and remains very relevant. The changing natural and climatic conditions of the region require careful selection of an assortment of tree and shrub species and preparations that improve their growth, development and resistance to environmental factors. Purpose. Study of the influence of polymer materials on the species of hanging birch (Betula pendula Roth.), branched tamarix (Tamarix ramosissima Ledeb.), black poplar (Populus nigra L.) in arid conditions. Materials and methods. The effect of three forms of Hydrosous polyacrylamide (HS) was studied: granular in doses 0, 30, 60, 120, 480, 960, 1920 kg/ha, powdered at a dose of 480 kg /ha, saturated with macro- and micro-fertilizers at a dose of 480 kg/ ha on birch and tamarix with the use of fine-drip irrigation, the distance between the centers of the seed rows are 40 cm . The seeding rate of class 1 seeds was 7 g/1 m of the seeding groove. The experiment also included options with mulching birch crops with sawdust 1-2 mm thick, peat 1-2 mm and straw 2-3 cm. In the variant of the experiment with black poplar, sowing seeds in a hydrogel suspension, sowing seeds in water, sowing seeds with dry hydrogel granules, sowing dry seeds (control) were used. Freshly harvested seeds, stirring periodically, were germinated for 36 hours in a hydrogel suspension and an aqueous medium. 5 kg of hydrogel polymer, 100 kg of peat, 10 m3 of water and 40 kg of seeds were used for the preparation of the hydrogel suspension, 0.5 polymer, 10 g of humus and 4 g of seeds were added per 1 ha or 1 liter of water. Results. According to the results of the experiment, birch seedlings grew and developed better in the variant with the introduction of a granular polymer of 960 kg / ha – the diameter of the root neck was 4.8 mm, when the polymer was applied at a dose of 1600 kg / ha, the first shoots after sowing appeared after 14 days. When taking soil samples in tamarix crops, its moisture content was 25.8% in the experiment variant with a polymer dosage of 1600 kg/ha, the best density was observed in the experiment variant with a polymer dosage of 3200 kg/ha. The size and yield of 2-year-old tamarix seedlings when hydrophilic polymers were introduced into the soil turned out to be better in the experiment variant with a dose of 1600 kg/ha. The black poplar showed the best growth results in the variant of sowing in a suspension of hydrogels, the linear growth of seedlings in height was 9.6 cm. Conclusions. Sowing germinated seeds of black poplar (Populus nigra L.) in a liquid medium in the presence of hydrogels and fertilizers allows to increase seed germination, reduce the time of emergence of mass seedlings, accelerate growth rates, improve the quality of seedlings. Polyacrylamide Hydrosous allows you to increase soil moisture, lower its density, which is important for the arid conditions of the research region. During the growth and development of plants under the influence of Hydrosous, the diameter of the root neck of seedlings increased, the dynamics of growth in height and the dates of the appearance of the first shoots decreased.

Unlike trees, shrubs (i.e., multiple-stemmed woody plants) do not need evenly spaced large diameter structural roots and therefore should be more responsive to heterogeneous distributions of soil resources and spread further per unit belowground biomass. We therefore hypothesized that compared to trees, shrubs respond more to asymmetric distributions of nutrients, reach nutrient-rich patches of soil faster, and do so with less below-ground biomass. To test these three hypotheses, we planted individual seedlings of shrubs (Cornus racemosa, Rhus glabra, and Viburnum dentatum) and trees (Acer rubrum, Betula populifolia, and Fraxinus americana) in the centers of sand-filled rectangular boxes. In one direction we created a stepwise gradient of increasing nutrients with slow-release fertilizer; in the other direction, no fertilizer was added. Seedlings were harvested when their first root reached the plexiglass-covered fertilized end of their box; time taken, above-ground biomass, and below-ground biomass per nutrient segment were determined. Shrubs and trees did not consistently differ in precision of root foraging (i.e., the ratio of biomass in the fertilized and unfertilized soil) or in rates (g/day) and efficiencies (cm/day) of lateral root growth. Interspecific variation appeared more related to species' habitats than to growth form. The fastest and most efficient roots were produced by the shrub (R. glabra) and the tree (B. populifolia), both characteristic of poor and heterogeneous soils. Root foraging by R. glabra was also facilitated by rapid rhizomatous expansion. [ABSTRACT FROM AUTHOR]

Copyright of German International Journal of Modern Science / Deutsche Internationale Zeitschrift für Zeitgenössische Wissenschaft is the property of Artmedia24 and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article provides brief information about the North American exposition of the Tashkent Botanical Garden of Uzbekistan. The species of plants growing today in this exposition are given. [ABSTRACT FROM AUTHOR]

Abstract The carbon stock, biomass, and CO2 emissions in woody species play crucial roles in understanding and managing ecosystems. Understanding these aspects is crucial for sustainable forest management, conservation, and mitigating the impact of woody species on global carbon dynamics and climate change. This study examined the nexus between carbon stock, biomass, and CO2 emission of woody plant composition in disturbed and undisturbed areas in Southwestern Nigeria. The study involved the random establishment of plots in the disturbed and undisturbed areas and, in each plot, the woody plants were enumerated and identified to the species level. The results showed that total biomass (102.645 Mg ha-1), total carbon stock (51.323 Mg C ha-1), and total CO2 emission (188.354 Mg C ha-1) values of tree species in undisturbed plots were higher than the values of total biomass (70.768 Mg ha-1), total carbon stock (35.384 Mg C ha-1), and total CO2 emission (129.859 Mg C ha-1) recorded in disturbed plots. The results also revealed that total biomass (0.123 Mg ha-1), total carbon stock (0.061 Mg C ha-1), and total CO2 emission (0.225 Mg C ha-1 ) values of shrub species recorded in disturbed plots were higher than values of total biomass (0.067 Mg ha-1), total carbon stock (0.034 Mg C ha-1) and total CO2 content (0.124 Mg C ha-1) recorded in undisturbed plots, respectively. The findings showed that in undisturbed and disturbed plots of shrubs, biomass, carbon and CO2 emissions have a strong positive correlation of 1.000**. While biomass, carbon, and CO2 emission have a very strong positive correlation (0.999**) in undisturbed plots of trees, the biomass, carbon, and CO2 emission have moderate to strong positive correlations (0.458** to 0.974**) in disturbed plots of the tree. The study concluded that while biomass, carbon stock, and CO2 emission values of tree species were higher in undisturbed plots than in disturbed plots, the biomass, carbon stock, and CO2 emission values of shrub species were lower in undisturbed plots than in disturbed plots. It also concluded that the main purpose of establishing reserve forests is not totally achieved as human activities occurring in reserve forests still contribute to the increment of climate change.

The carbon stock, biomass, and CO2 emissions in woody species play crucial roles in understanding and managing ecosystems. Understanding these aspects is crucial for sustainable forest management, conservation, and mitigating the impact of woody species on global carbon dynamics and climate change. This study examined the nexus between carbon stock, biomass, and CO2 emission of woody plant composition in disturbed and undisturbed areas in Southwestern Nigeria. The study involved the random establishment of plots in the disturbed and undisturbed areas and, in each plot, the woody plants were enumerated and identified to the species level. The results showed that total biomass (102.645 Mg ha-1), total carbon stock (51.323 Mg C ha-1), and total CO2 emission (188.354 Mg C ha-1) values of tree species in undisturbed plots were higher than the values of total biomass (70.768 Mg ha-1), total carbon stock (35.384 Mg C ha-1), and total CO2 emission (129.859 Mg C ha-1) recorded in disturbed plots. The results also revealed that total biomass (0.123 Mg ha-1), total carbon stock (0.061 Mg C ha-1), and total CO2 emission (0.225 Mg C ha-1) values of shrub species recorded in disturbed plots were higher than values of total biomass (0.067 Mg ha-1), total carbon stock (0.034 Mg C ha-1) and total CO2 content (0.124 Mg C ha-1) recorded in undisturbed plots, respectively. The findings showed that in undisturbed and disturbed plots of shrubs, biomass, carbon and CO2 emissions have a strong positive correlation of 1.000**. While biomass, carbon, and CO2 emission have a very strong positive correlation (0.999**) in undisturbed plots of trees, the biomass, carbon, and CO2 emission have moderate to strong positive correlations (0.458** to 0.974**) in disturbed plots of the tree. The study concluded that while biomass, carbon stock, and CO2 emission values of tree species were higher in undisturbed plots than in disturbed plots, the biomass, carbon stock, and CO2 emission values of shrub species were lower in undisturbed plots than in disturbed plots. It also concluded that the main purpose of establishing reserve forests is not totally achieved as human activities occurring in reserve forests still contribute to the increment of climate change. Highlights: • Undisturbed areas had higher tree carbon and CO2 levels, emphasizing their role in carbon sequestration. • Disturbed plots showed higher shrub biomass, suggesting unexpected ecological responses to disturbances. • Despite efforts, reserve forests face challenges, as human activities contribute to climate change impacts. [ABSTRACT FROM AUTHOR]

Biscogniauxia species are opportunistic pathogens primarily associated with Quercus species dieback in the Mediterranean basin. Among these species, Biscogniauxia mediterranea stands out as the only species previously documented in Tunisia, affecting Quercus suber and Erica multiflora. This study unveils a novel finding, reporting the presence of Biscogniauxia rosacearum on Strawberry trees in Tunisia. The identification of B. rosacearum isolates was confirmed based on DNA sequence data (ITS, TUB2 and ACT) and morphological traits. Artificial inoculation trials on leaves confirmed the pathogenicity of the fungus towards Arbutus unedo. This finding emphasizes the significance of implementing proactive measures to effectively combat this pathogen because of the polyphagous nature of Biscogniauxia species that raises concerns about its potential spread within vulnerable hosts in Tunisian oak forests. [ABSTRACT FROM AUTHOR]

Background and aims: Belowground interspecific plant facilitation is supposed to play a key role in enabling species co-existence in hyperdiverse ecosystems in extremely nutrient-poor, semi-arid habitats, such as Banksia woodlands in southwestern-Australia. Manganese (Mn) is readily mobilised by Banksia cluster root activity in most soils and accumulates in mature leaves of native Australian plant species without significant remobilisation during leaf senescence. We hypothesised that neighbouring shrubs are facilitated in terms of Mn uptake depending on distance to surrounding cluster root-forming Banksia trees. Methods: We mapped all Banksia trees and selected neighbouring shrubs within a study site in Western Australia. Soil samples were collected and analysed for physical properties and nutrient concentrations. To assesses the effect of Banksia tree proximity on leaf Mn concentrations [Mn] of non-cluster-rooted woody shrubs, samples of similarly aged leaves were taken. We used multiple linear models to test for factors affecting shrub leaf [Mn]. Results: None of the assessed soil parameters showed a significant correlation with shrub leaf Mn concentrations. However, we observed a significant positive effect of very close Banksia trees (2 m) on leaf [Mn] in one of the understorey shrubs. We found additional effects of elevation and shrub size. Conclusions: Leaf micronutrient concentrations of understorey shrubs were enhanced when growing within 2 m of tall Banksia trees. Our model predictions also indicate that belowground facilitation of Mn uptake was shrub size-dependent. We discuss this result in the light of plant water relations and shrub root system architecture. [ABSTRACT FROM AUTHOR]

Mycorrhizal associations of trees play a key role in ecosystem biogeochemistry, yet we know relatively little about the nutrient acquisition strategies of ericoid mycorrhizal (ErM) shrubs, despite their prevalence in forest understories. ErM shrubs tend to produce litter with high concentrations of polyphenols, which form decay‐resistant complexes with organic nitrogen (N). Some ErM fungi appear capable of producing a diverse suite of extracellular enzymes, but it is unclear whether this enables ErM shrubs to acquire the N from their own litter, and whether this ability is greater than that of ectomycorrhizal (EcM) trees, with which they commonly co‐occur. Here, we conducted two growth chamber experiments with 15N‐enriched root and leaf litters to determine whether EcM pine and ErM vaccinium differ in litter N acquisition from these sources. Grown individually, pine and vaccinium plants acquired 1 mg or 4% of the litter N after one year. Differences between pine and vaccinium in litter N acquisition were correlated with litter chemistry, where vaccinium acquired more N from litter with a high concentration of tannins and a high C:N, while pine acquired more N from litter with a high acid‐insoluble fraction. When plants were grown in pairs, the presence of a vaccinium neighbor reduced the biomass of both species by an average of 24%, but it only reduced litter N acquisition by pine (55%), demonstrating vaccinium's ability to compete with pine for litter N. Regardless of the competitive context, vaccinium allocated a greater percentage (76%) of its acquired litter N to aboveground biomass compared with pine (47%), suggesting vaccinium is more efficient at allocating this N to photosynthesis and growth. Our finding that EcM pine and ErM vaccinium have varying abilities to acquire N from these common litters suggests a degree of niche complementarity, which may facilitate the coexistence of these plants in forest ecosystems. However, our results also suggest that, at high densities, ErM vaccinium has the potential to suppress the growth and N acquisition of EcM pine. Distinct strategies of EcM trees and ErM shrubs for acquiring and using N have the potential to shape biogeochemical cycles of many forested ecosystems. [ABSTRACT FROM AUTHOR]

Nowadays, comparative, polyconfrontative and cognitive-onomasiological studies of dendronyms as one of the oldest vocabulary layers are relevant areas of modern linguistics. This study aims to determine the etymology of the scientific names of cultivated trees and shrubs, to reconstruct the motivators of the dendronyms nomination. Etymological analysis of dendronyms and the comparative method were used in the research, the material was 16 binomial names. The conducted analysis proved that the process of nomination of trees and shrubs in Latin and Ukrainian is mostly based on the mechanisms of propositional and dictum motivation, which fixes true knowledge about the object in the name structure. In both Latin and Ukrainian, the reconstruction of the motivators of many names of trees and shrubs remains hypothetical. Since the process of domestication of trees and shrubs has a long history, many dendronyms names in both Latin and Ukrainian have Proto-Indo-European roots. [ABSTRACT FROM AUTHOR]

The aim of this study was to select and evaluate promising potential indigenous fodder trees and shrubs (IFTS) as supplemental feeds for ruminant animals. Through interviews with farmers and field inventories, 107 IFTS species were identified as ruminant feeds, from which 37 potential IFTS species were selected. The chemical composition and anti-nutritional factors of the selected IFTS were analysed. Among the 37 selected IFTS species, crude protein (CP) ranged from 83.3 to 230.5 (mean, 134.3) g kg−1 dry matter (DM); CP was greater than 80 g kg−1 DM in all selected species. Condensed tannin (CT) content varied from 2.57 to 210.91 g kg−1 (p < 0.05) among the selected species, of which 72% had < 40 g kg−1 DM, an amount that is tolerable for ruminants. Farmers' preferences and the nutritive value of the selected fodder species were positively correlated (p < 0.05) for CP (0.61), organic matter digestibility (0.303) and metabolisable energy (0.25). Farmers' preference ranking and the nutritive value of the plants were considered to select the top 14 IFTS, all of which had CP > 110 g kg−1, neutral detergent fibre (NDF) < 350 g kg−1, and CT < 40 g kg−1. Thus, the selected potential IFTS need further evaluation for their agronomic practice, biomass production and animal performance. [ABSTRACT FROM AUTHOR]

Purpose: Elucidating the interactions of above- and below-ground communities in forest ecosystems is of great importance for comprehending biodiversity maintenance and ecosystem functioning. Methods: In the context of a Biodiversity and Ecosystem Functioning experiment conducted in China (BEF-China), we explored the combined effects of tree species richness (1, 2, and 4) and shrub species richness (0, 2, 4, and 8) on soil fungal community diversity and structure under tree species with different mycorrhizal types (i.e., arbuscular mycorrhizal (AM) tree and ectomycorrhizal (EM) tree) using the Illumina sequencing method. Results: Results demonstrated that the fungal alpha diversity, community composition and network structure were significantly different between EM trees and AM trees. Although tree and shrub species richness had no significant interactive effect on soil fungal alpha diversity regardless of tree mycorrhizal types, however, their interactions did influence fungal community composition and co-occurrence network structure. Specifically, the interactive effect of tree and shrub species richness on soil fungal community composition was observed in AM trees, and their interactions affected the soil fungal co-occurrence network structure in EM trees. Conclusions: These findings highlight the tree mycorrhizal type dependence of the interactive effects of tree and shrub species richness on soil fungal communities in a subtropical forest. [ABSTRACT FROM AUTHOR]

Simple Summary: Edible trees and shrubs have been evaluated to improve animal nutrition and mitigate the emission of greenhouse gasses from ruminants. In the present study, researchers visited some farmers and identified eight potentially edible Brazilian trees. Nutritional value and gas (and methane) production from these edible trees were evaluated. The leaves of Aroeira, Candeia, and Jatobá had limited nutritional value. Samples of Santa Bárbara trees, Mulberry, and Tithonia showed an improved nutritional value. Furthermore, Tithonia decreased methane emissions and is a potentially edible tree for multifunctional redesigned ruminant production systems. The present study aims to evaluate the nutritional value of different tree and shrub leaves in Brazilian ruminant production systems. Eight potentially edible trees and shrubs were identified from interviews with 30 ruminant producers: Aroeira (ARO; Lithraea molleoides), Black Mulberry (BMU; Morus nigra), Candeia (CAN; Eremanthus erythropappus), Jatobá (JAT; Hymenaea courbaril), Gliricídia (GLI; Gliricidia sepium), Santa Bárbara tree (SBT; Mélia azedarach), Tithonia (TIT; Tithonia diversifolia), and White Mulberry (WMU; Morus alba). Four leaf samples of each edible tree were sampled, and chemical analyses and in vitro assays were performed. Edible trees (except CAN and JAT) had lower neutral detergent fiber content than Mombasa grass. In addition, SBT, BMU, WMU, and TIT had lower fiber content than the other evaluated edible trees. Consequently, SBT, TIT, BMU, and WMU had improved dry matter degradation. Among the edible trees and shrubs, SMW and WMU increased the potential for gas production (a parameter). On the other hand, CAN decreased the estimated gas production 48 h after incubation. Furthermore, TIT decreased methane production up to 24 h after in vitro fermentation. Thus, except ARO, CAN, and JAT, the edible trees evaluated in the present study are potential feeds in moderate- to high-producing animals. Additionally, TIT fermentation reduces in vitro methane production. [ABSTRACT FROM AUTHOR]

Despite the importance of species interaction in modulating the range shifts of plants, little is known about the responses of coexisting life forms to a warmer climate. Here, we combine long-term monitoring of cambial phenology in sympatric trees and shrubs at two treelines of the Tibetan Plateau, with a meta-analysis of ring-width series from 344 shrubs and 575 trees paired across 11 alpine treelines in the Northern Hemisphere. Under a spring warming of +1°C, xylem resumption advances by 2–4 days in trees, but delays by 3–8 days in shrubs. The divergent phenological response to warming was due to shrubs being 3.2 times more sensitive than trees to chilling accumulation. Warmer winters increased the thermal requirement for cambial reactivation in shrubs, leading to a delayed response to warmer springs. Our meta-analysis confirmed such a mechanism across continental scales. The warming-induced phenological mismatch may give a competitive advantage to trees over shrubs, which would provide a new explanation for increasing alpine treeline shifts under the context of climate change. [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate floristic diversity of the dry forest of the Agua Blanca commune, Machalilla - Puerto López parish, through the use of a descriptive and evaluative methodology. It was carried out using descriptive statistics of graphic bars for the floristic inventory. The mathematical method of the Shannon-Weaver index and the Ecological Importance Value Index (IVIE) was used. Monitoring plots were established covering an area of 6,100 m² (20 x 305 meters) with six sampling points in the dry forest of the Agua Blanca commune, within which nine floristic species were identified, the most dominant being the shrub moyuyo; The Shannon-Weaver index indicated a medium diversity with a value of 1.61, while the IVIE showed that the species Cordia lutea Lam. (36.99%), Bursera graveolens (Kunth) (20.66%), Cereus jamacaru (10.47%) have greater ecological importance in the dry forest of the Agua Blanca commune. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Sciences, Life & Applied Sciences is the property of Arab Journal of Sciences & Research Publishing (AJSRP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant responses to air pollution have been extensively studied in urban environments. Nevertheless, detailed and holistic studies assessing their retaliation to air contaminants are still limited. The present study evaluates the effect of criteria pollutants (SO2, NO2, PM10 and O3) on the overall biochemistry and resource allocation strategy of plants in order to categorize the dominant roadside species (Mangifera indica, Psidium guajava, Ficus religiosa, Azadirachta indica, Dalbergia sissoo, Cascabela thevetia and Bougainvillea spectabilis) of the Indo-Gangetic Plains (IGP), with different morphologies and habits, into species that are tolerant and sensitive to the prevailing air pollutants. This study was performed at three different land-use sites (industrial, commercial and reference) in Varanasi for two seasons (summer and winter). It was inferred that NO2 and PM10 consistently violated the air quality standards at all the sites. The fifteen assessed parameters reflected significant variations depending upon the site, season and plant species whereupon the enzymatic antioxidants (superoxide dismutase and catalase) and resource utilization parameters (leaf area and leaf dry matter content) were remarkably affected. Based on the studied parameters, it was entrenched that deciduous tree species with compound leaves (D. sissoo > A. indica) were identified as the less sensitive, followed by a shrub (C. thevetia > B. spectabilis), while evergreen species with simple leaves were the most sensitive. It was also substantiated that the morphology of the foliage contributed more toward the differential response of the plants to air pollutants than its habit.

Plant responses to air pollution have been extensively studied in urban environments. Nevertheless, detailed and holistic studies assessing their retaliation to air contaminants are still limited. The present study evaluates the effect of criteria pollutants (SO2, NO2, PM10 and O3) on the overall biochemistry and resource allocation strategy of plants in order to categorize the dominant roadside species (Mangifera indica, Psidium guajava, Ficus religiosa, Azadirachta indica, Dalbergia sissoo, Cascabela thevetia and Bougainvillea spectabilis) of the Indo-Gangetic Plains (IGP), with different morphologies and habits, into species that are tolerant and sensitive to the prevailing air pollutants. This study was performed at three different land-use sites (industrial, commercial and reference) in Varanasi for two seasons (summer and winter). It was inferred that NO2 and PM10 consistently violated the air quality standards at all the sites. The fifteen assessed parameters reflected significant variations depending upon the site, season and plant species whereupon the enzymatic antioxidants (superoxide dismutase and catalase) and resource utilization parameters (leaf area and leaf dry matter content) were remarkably affected. Based on the studied parameters, it was entrenched that deciduous tree species with compound leaves (D. sissoo > A. indica) were identified as the less sensitive, followed by a shrub (C. thevetia > B. spectabilis), while evergreen species with simple leaves were the most sensitive. It was also substantiated that the morphology of the foliage contributed more toward the differential response of the plants to air pollutants than its habit. [ABSTRACT FROM AUTHOR]

Pittosporum (Pittosporaceae, Apiales), an attractive genus of horticulturally important trees and shrubs, is revised for Malesia (Malaysia, Singapore, Indonesia, Brunei Darussalam, the Philippines, Timor-Leste) and Papuasia (Papua Barat (Indonesia), Papua New Guinea and the Solomon Islands). In this report, 52 species are recognised, including many species reinstated from synonymy. Three taxa are raised to species rank (P. owenstanleyense, P. patelliplacenta and P. purpurascens), one is a new combination in Pittosporum (P. impressum), and four new species are described: P. sulawesiense, P. isolatum, P. schoddei and P. sogeriense. [ABSTRACT FROM AUTHOR]

Mediterranean ecosystems are threatened by climate change and shrub encroachment. An increase in shrub cover can intensify the competition for water, aggravating the impacts of drought on ecosystem functioning. The effects of shrubs can be positive or negative, depending on the shrub species and density. We used a Mediterranean cork oak (Quercus suber) woodland to investigate the effects of increasing gum rockrose (Cistus ladanifer) cover on leaf carbon assimilation (Amax) and tree growth. The experiment consisted of a gradient of shrub cover, with four treatments: control, LD, MD, and HD, with 0%, 25%, 45%, and maximum shrub cover (>90%), respectively. Increasing shrub cover significantly decreased Amax in trees from HD (−15%) compared to control treatment, with intermediate effects on trees from LD (−5%) and MD (−12%). There was a large variability in tree growth, resulting in no significant effects of shrub cover, despite higher trunk diameter relative increments in LD (+40%), and lower in MD (−17%) and HD (−32%) compared to the control. The results indicate that a dense shrub cover (>90%) affected cork oak carbon assimilation and growth, while a low-to-medium shrub cover (≤45%) only induced mild intermediate effects. This information is important for the effective management of shrub density to improve the health and productivity of cork oak woodlands. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) is a serious air pollutant that poses significant health risks. One solution to reduce PM concentrations in these areas is through phytoremediation, a process that involves using plants to remove contaminants from the environment. In this study, we investigated the capacity of spontaneous flora—herbaceous plants, shrubs, and trees growing in five zones from the road—to absorb PM on their foliage. The study found significant differences in the accumulation of PM, with the highest PM accumulation recorded in Zone V, which boasted a blend of the three mentioned vegetation types together. In contrast, Zones I and II, which were located close to the road and comprised solely herbaceous plants, exhibited 14.3% and 43.4% less PM accumulation, respectively. Similarly, Zone IV, with a mix of herbaceous plants and shrubs, showed 64.5% less PM accumulation, while Zone III, with only herbaceous plants, had a staggering PM accumulation reduction of 76.8%. The sum of Si+Al+Ca displayed a similar pattern. Furthermore, the findings highlighted the valuable role of plants in decreasing PM concentrations in the air, resulting in reductions of 76%, 39%, and 47% for PM10, PM2.5, and PM1.0, respectively. The results indicate that various spontaneous flora can work in unison to reduce PM, providing a multifaceted approach to combating air pollution. [ABSTRACT FROM AUTHOR]

Mediterranean ecosystems face threats from both climate change and shrub invasion. As shrub cover increases, competition for water intensifies, exacerbating the negative effects of drought on ecosystem functioning. However, research into the combined effects of drought and shrub invasion on tree carbon assimilation has been limited. We used a Mediterranean cork oak (Quercus suber) woodland to investigate the effects of drought and shrub invasion by gum rockrose (Cistus ladanifer) on cork oak carbon assimilation and photosynthetic capacity. We established a factorial experiment of imposed drought (ambient and rain exclusion) and shrub invasion (invaded and non-invaded) and measured leaf water potential, stomatal conductance and photosynthesis as well as photosynthetic capacity in cork oak and gum rockrose over one year. We observed distinct detrimental effects of gum rockrose shrub invasion on the physiological responses of cork oak trees throughout the study period. Despite the imposed drought, the impact of shrub invasion was more pronounced, resulting in significant photosynthetic capacity reduction of 57% during summer. Stomatal and non-stomatal limitations were observed under moderate drought in both species. Our findings provide significant knowledge on the impact of gum rockrose invasion on the functioning of cork oak and can be used to improve the representation of photosynthesis in terrestrial biosphere models. [ABSTRACT FROM AUTHOR]

Nitrogen (N), acquired by roots and mycorrhizal fungi and supplied to plant foliage, is a growth‐limiting nutrient at the subarctic treeline. Due to this limitation, interspecific competition and acquisition of N is an important control on plant community composition and distribution. The ability of trees and shrubs to access N shapes community dynamics at this ecotone undergoing species range shifts and changes in primary productivity driven by climate change. Using 15N soil labelling we investigate the fate of soil inorganic N, and spatial distances over which trees and understorey shrubs access soil N, in a treeline forest. 15N was injected into soil rooting zones in discrete 1 m2 patches and foliar samples were collected from trees between 1 and 50 m away, and understorey shrubs between 0.5 and 11 m away from labelled soil. The 15N label was found in mountain birch trees up to 5 m, and in understorey shrubs up to 2 m, away from labelled soil. We estimate that 1.27% of pulse‐derived N was found in foliage of birch trees, compared to 1.16% in the understorey. However, mountain birch trees contributed only 31% of ecosystem leaf area index (LAI), thus there was a disproportionate allocation of added label to the birch canopy compared with its contribution to ecosystem LAI. The difference in root and mycorrhizal exploration distances and community N partitioning between mountain birch trees and understorey shrubs may confer competitive advantage to trees with respect to nitrogen and nutrient patches, which may alter plant community structures within these forests. This is particularly important considering predicted climate‐driven tree and tall shrub expansion in subarctic regions, with likely consequences for ecosystem N and carbon (C) cycling, as well as for community composition and biodiversity. [ABSTRACT FROM AUTHOR]

Iran, possessing unique topographic and diverse climatic conditions, is the home of 8167 vascular plant species. Iran has a historical tradition in using plants for medicinal purposes. Approximately 2075 species over the whole are popularly characterized as medicinal or aromatic. Medicinal trees and shrubs compose a significant percentage of Iranian medicinal flora. Nonetheless, there are no integrated databases on their applications and most of the publications and documents have been scattered to date. Therefore, the present investigation aims to integrate the published literature considering its ethnobotanical aspects that would serve as promising precursors for developing potent medicines of plant origin. In the study, we compile information about ethnobotany of trees and shrubs of Iran. Our survey found 174 taxa belonging to 109 genera and 56 families. The majority of species were classified in Rosaceae, Fabaceae, Rutaceae, Salicaceae, and Lamiaceae families. Rosaceae was the most dominant, representing 21.8% of the total plant species recorded, among them, the genus with the highest number of species was Prunus (16 species). Berberis vulgaris, Citrus limon, and Betula pendula have the highest number of medicinal uses (24 number of uses) in Iran. Leaves (22.7%) represented the most dominant usage of the plant parts, while the most commonly used preparation method was infusion (33.5%). Most of the plant species have been consumed for digestive system treatment (21%), followed by immune system treatment (20%). The present review highlights that different trees and shrubs taxa have great traditional applications in various healing throughout the Iranian territory. The represented data can potentially be a precious reference containing useful information for directing further phytochemical, biological, and pharmacological investigations. Several endemic species of trees and shrubs, particularly Ribes khorasanicum, are frequently used in Iranian traditional medicine. Because of overharvesting, these species are calling a wake-up alarm for conservation. [ABSTRACT FROM AUTHOR]

In post‐fire Siberian larch forests, where tree density can vary within a burn perimeter, shrubs constitute a substantial portion of the vegetation canopy. Leaf area index (LAI), defined as the one‐sided total green leaf area per unit ground surface area, is useful for characterizing variation in plant canopies. We estimated LAI with allometry for trees and tall shrubs (>0.5 and <1.5 m) across 26 sites with varying tree stem density (0.05–3.3 stems/m2) and canopy cover (4.6%–76.9%) in a uniformly‐aged mature Siberian larch forest that regenerated following a fire ∼75 years ago. We investigated relationships between tree density, tree LAI, and tall shrub LAI, and between LAI and satellite observations of Normalized Difference and Enhanced Vegetation Indices (NDVI and EVI). Across the density gradient, tree LAI increases with increasing tree density, while tall shrub LAI decreases, exhibiting no patterns in combined tree‐shrub LAI. We also found significant positive relationships between tall shrub LAI and NDVI/EVI from PlanetScope and Landsat imagery. These findings suggest that tall shrubs compensate for lower tree LAI in tree canopy gaps, forming a canopy with contiguous combined tree‐shrub LAI across the density gradient. Our findings suggest that NDVI and EVI are more sensitive to variation in tall shrub canopies than variation in tree canopies or combined tree‐shrub canopies in these ecosystems. The results improve our understanding of the relationships between forest density and tree and shrub leaf area and have implications for interpreting spatial variability in LAI, NDVI, and EVI in Siberian boreal forests. Plain Language Summary: After wildfires burn forests in northeast Siberia, they often grow back unevenly, with some sections containing many more trees than others. Sections with more trees have a higher capacity to take up carbon and higher rates of energy production, which has important implications for climate change. To investigate how vegetation varies across sections of a forest which burned in 1940, we estimated the separate and combined contributions of trees and tall shrubs (>0.5 and <1.5 m) in high, medium, and low density sections using tree and shrub stem diameter measurements. We estimated the canopy vegetation in each section of forest by calculating the total area of leaves in the section and dividing it by the total ground area, producing the leaf area index (LAI). In sections with less dense tree cover, tall shrubs made up for lower tree leaf area, and the combined leaf area of trees and tall shrubs was consistent across the sections of different tree density. We also compared our leaf area measurements with measures of vegetation productivity produced from satellite imagery, finding that the satellite measures were correlated with tall shrub LAI, but not with tree LAI or combined LAI from trees and shrubs. Key Points: Tall shrubs compensate for lower tree leaf area in low density larch forestsCombined leaf area of trees and tall shrubs is consistent across a range of forest tree densitiesSatellite‐derived v egetation indices are more closely linked to shrub LAI than tree LAI or combined tree‐shr LAI [ABSTRACT FROM AUTHOR]

Different species-specific traits of woody plant species, feeding preferences of herbivores together with resulting effects on plant competition are expected to translate into different plant community structures and expressions of biodiversity. We studied the diversity of woody plant species (trees and shrubs) and structural diversity of forest trees, using a 30-year and an 18-year dataset of ungulate exclosure-control plot pairs in a mixed alpine forest community in Austria. We surveyed the tallest individuals per tree species and plot and analyzed the collective of top-height individuals per plot pair. Incidence data for exclosure and control plots were aggregated. Comparing species diversity and diversity of height classes on the plots throughout time, we calculated diversity profiles based on Hill numbers. Diversity of top height individuals and structural diversity, expressed by height classes, were two diversity aspects that differed between exclosures and control plots. Other diversity estimates of woody plant species showed huge variation without significant differences between plots. Height growth was significantly suppressed by ungulate herbivory. Effects of ungulate herbivores in forest ecosystems are highly complex and context-dependent and thus not reducible to simple top-down forces. Long-term surveys provide data that reflect "ultimate" effects of herbivory interacting with other drivers of community dynamics. [ABSTRACT FROM AUTHOR]

An important area of research in the context of ensuring the sustainable development of urban ecosystems is the development of theoretical and applied aspects of the possibilities of obtaining information about the ecosystem usefulness of green spaces. The concept of evaluating and paying for eco-services that produce trees and shrubs for the environment and society is characterised by substantial international interest. In this context, it is important to analyse modern tools and techniques that can adequately determine and evaluate the amount of ecosystem services, which was the main goal of the study. In this paper, the possibility of using the i-Tree Eco tools for quantitative and cost determination of the volume of ecosystem services created by park spaces in the green space inventory process is tested. For this purpose, on the example of the prefix part of the Rayivskyy landscape park of the Ternopil region, the measurement of biometric and sanitary indicators of trees during their inventory was conducted, a number of ecosystem services of plants were determined (reduction of pollutants, absorption and sequestration of carbon, oxygen production, and regulation of avoided runoff), the replacement cost of trees was established, the data obtained were analysed, the interpretation of the information received in the form of an interactive electronic map was performed, and the advantages and disadvantages of this process were determined. The study showed that the cost of ecosystem services (in the context of the indicators under study) for the attached part of the Rayivskyy landscape park is 81894 UAH (€3044) per year, and the total replacement cost of the examined plantings is 4486,464 thousand UAH (€166,783). The monetised expression of the ecosystem utility of this plantation creates conditions for improving the understanding of the value of the phytocenosis for urban landscapes. The practical value of the study is the possibility of using its results to improve and increase the information content of the green space inventory process, by obtaining information about ecosystem services of trees in quantitative and cost terms to increase the validity of decisions in the field of nature management. [ABSTRACT FROM AUTHOR]

The floristic composition of a fragment of restored Tamaulipan thornscrub and the response of six native woody species used for this purpose were evaluated, as well as two that were established naturally, through the attributes of the community and the da-sometric variables of the species used (crown cover, height, normal diameter, and volume). 12 sites of 10 x 10 m were sampled, where tree cover (m²), normal diameter (cm), total height (m), and volume (m³) were evaluated for the eight studied species. The results indicate that the eight species exhibit statistically significant differences in their crown cover, height, normal diameter, and volume. The species with higher values regarding their dasome-tric variables were Parkinsonia aculeata and Acacia farnesiana. [ABSTRACT FROM AUTHOR]

Residential yards are a form of urban land use that cover a considerable amount of area in cities worldwide and provide important habitat for wildlife, especially when landscaped with native plants. Nevertheless, most native‐plant landscaping and wildlife research in the northern temperate regions of the world has been conducted during the spring and summer breeding period, leaving a gap in our understanding of the importance of residential yards and native plants as habitats for animals during the nonbreeding period. To fill this gap, we quantified the ecological role of native‐landscaped yards to avifauna throughout Greater Los Angeles (LA), California, during the winter nonbreeding period, which is a time of year when the region hosts a high abundance and diversity of migratory and resident birds. We surveyed birds and habitat features from October to March of 2020 and 2021 at 22 pairs of native‐ and non‐native‐landscaped yards plus 10 additional native‐landscaped yards. We had three objectives for our study. First, we compared avifaunal communities, including feeding and nonfeeding behaviors, and habitat features between native and non‐native‐landscaped yards. Second, we quantified relationships between habitat features and bird richness, abundance, and feeding and nonfeeding behaviors—focusing on species affiliated with urban or natural terrestrial ecosystems of the region. Third, we documented feeding and nonfeeding behaviors by birds with native and non‐native plants. Native‐landscaped yards had a greater cover of native trees, shrubs, and herbaceous plants, and a higher cover of natural habitat elements, including leaf litter and bare‐ground cover. Bird richness and abundance—especially bird species affiliated with tree‐ and shrub‐dominated ecosystems—were greater in native than non‐native‐landscaped yards. Further, yards with a higher cover of native plants supported greater numbers of feeding birds, with individuals focusing their foraging behaviors on distinct native trees and shrubs, including Quercus spp. (oak), Heteromeles spp. (toyon), Arctostaphylos spp. (manzanita), and Salvia spp. (sage). Our results suggest that residential yards landscaped with native plants provide important habitat for birds during the nonbreeding period and are a viable approach for residents and cities if improving conditions for birds throughout the annual cycle is a goal. [ABSTRACT FROM AUTHOR]

Chlorophyll a fluorescence (ChF) signal analysis has become a widely used and rapid, non-invasive technique to study the photosynthetic process under stress conditions. It monitors plant responses to various environmental factors affecting plants under experimental and field conditions. Thus, it enables extensive research in ecology and benefits forestry, agriculture, horticulture, and arboriculture. Woody plants, especially trees, as organisms with a considerable life span, have a different life strategy than herbaceous plants and show more complex responses to stress. The range of changes in photosynthetic efficiency of trees depends on their age, ontogeny, species-specific characteristics, and acclimation ability. This review compiles the results of the most commonly used ChF techniques at the foliar scale. We describe the results of experimental studies to identify stress factors that affect photosynthetic efficiency and analyse the experience of assessing tree vigour in natural and human-modified environments. We discuss both the circumstances under which ChF can be successfully used to assess woody plant health and the ChF parameters that can be useful in field research. Finally, we summarise the advantages and limitations of the ChF method in research on trees, shrubs, and woody vines. [ABSTRACT FROM AUTHOR]

This article presents an updated list of annotated invasive trees and shrubs in Latvia. This list includes 178 taxa about which extensive information has been collected and analysed: family, first records in the area, native range, invasiveness status, vector of introduction, and species distribution in Latvia. In this article, the authors, for the first time in Latvia, provided an invasiveness risk assessment and distinguished risk classes for trees and shrubs. The methodology previously developed by E. Weber and D. Gut was used to assess the risk of invasiveness. The most widely represented families in the list of invasive trees and shrubs are Rosaceae (51 taxa or 28.65%) and Salicaceae (20 taxa or 11.24%). Having assessed the invasiveness status, two species (Acer negundo L. and Sorbaria sorbifolia (L.) A. Braun) were identified as transformers, and 42 tree and shrub taxa were identified as invasive. After the assessment of the invasiveness risk, the species were divided into three risk classes. The highest risk class includes 32 taxa that are threatening or are likely to threaten natural habitats in Latvia in the future. The results of this study can be used for further dendrological studies in relation to global change and for practical nature conservation and landscape gardening. [ABSTRACT FROM AUTHOR]

The high diversity of trees and shrubs species in homegardens contributes to the provision of a variety of food products and medicinal plants, as well as greatly benefits the environment, improving the socioeconomic status of local communities and ecological sustainability. The purpose of this study is to characterize the diversity and composition of trees and shrubs in homegardens of Kampung Masjid Ijok, Perak, Malaysia, and to investigate the physical and socioeconomic factors that influence the diversity and composition of trees and shrubs in the systems. A total of 40 homegardens were surveyed. In total, 149 species of trees and shrubs were recorded. The mean number of tree and shrub species per homegarden was 40. The average number of trees and shrubs among homegardens ranged from 46 to 121. According to the size, homegardens were categorized into small, medium-sized and large and each category differed not only in the composition of trees and shrubs but also in the type of utilization. Physical and socioeconomic factors influence the composition and diversity of trees and shrubs. The major physical factor was the size of homegardens and the most important socioeconomic factor was the income status of the homegardens owner. The diversity and composition of trees and shrubs species increased as the size of the homegardens increased. Lower-income families are more reliant on homegrown food and medicinal plants, boosting the diversity and richness of tree and shrub species in these agroecosystems, and this relationship underscores the relevance of these agroecosystems as a food security strategy. [ABSTRACT FROM AUTHOR]

Scale insects are frequently abundant on urban trees. Although scales can worsen tree condition, some tree species tolerate moderate scale densities. Scales are prey for many natural enemies. Therefore, scale-infested trees may conserve natural enemies in their canopies and in nearby plants. We examined if scale-infested oaks—Quercus phellos L.—hosted more natural enemies than scale-uninfested oaks—Q. acutissima Carruth. and Q. lyrata Walter in Raleigh, NC. USA. We also tested if natural enemies were more abundant in holly shrubs (Ilex spp.) planted below scale-infested compared to scale-uninfested oaks. We collected natural enemies from the canopies of both tree types and from holly shrubs planted below these trees. To determine if tree type affected the abundance of natural enemies that passively dispersed to shrubs, we created hanging cup traps to collect arthropods as they fell from trees. To determine if natural enemies became more abundant on shrubs below scale-infested compared to scale-uninfested trees over short time scales, we collected natural enemies from holly shrubs below each tree type at three to six-day intervals. Scale-infested trees hosted more natural enemies than scale-uninfested trees and shrubs below scale-infested trees hosted more natural enemies than shrubs under scale-uninfested trees. Natural enemy abundance in hanging cup traps did not differ by tree type; however, shrubs underneath scale-infested trees accumulated more natural enemies than shrubs under scale-uninfested trees in six to nine days. Tolerating moderate pest densities in urban trees may support natural enemy communities, and thus biological control services, in shrubs below them. [ABSTRACT FROM AUTHOR]

Root metrics and plant height for 256 excavated saplings and small trees of 27 species, including sown plants, were used to describe belowground structure and assess factors that influence shoot growth in a tropical dry forest (TDF) in Zambia. Models were developed to (i) estimate taproot depth from incomplete excavations and (ii) coarse lateral root biomass from proximal diameter data. The majority of the species studied are slow-growing and had a median height of <200 cm at the age of 16 years. Root development advanced sequentially from taproot elongation to thickening to coarse lateral root development. Shrubs in shallow soil had short taproots with a lower wood density. Plant age explained <10% of the variance in shoot height. Root variables explained the majority of the variance in shoot height. More research is needed to improve our knowledge about how belowground structures influence shoot growth and tree recruitment in TDFs of southern Africa. [ABSTRACT FROM AUTHOR]

• Coupled modeling of porous medium and solar radiation for vegetation transpiration • The impacts of environmental factors on vegetation transpiration are quantified • Adjustment distance of Momentum to fully-developed region is less than Energy/Mass Vegetation cooling effects can effectively improve the outdoor microclimate. To explore the potential of vegetation transpiration cooling, we validated the feasibility of a new coupled porous medium and solar radiation model to simulate the interactions between vegetation transpiration and other physical processes in CFD. To emphasize the spatial extent of vegetation's influence, we compared and quantified the flow-adjustment distances(L FA) for wind speed, the temperature difference between simulated temperature and background temperature(ΔT (°C)), and water vapor mass fraction(ΔM w (g/kg)) between shrub(100m) and tree(200m) canopies: 1)For both vegetations, the L FA required for ΔT and ΔM w exceeds that of wind speed achieve fully-developed, indicating the momentum adjustment occurs more rapidly than energy and mass transport processes. 2)Vegetation drag effect depends on both leaf area density and vegetation canopy's height and width.3)Vegetation exhibits a significantly higher transpiration cooling effect under ambient relative humidity(RH) = 0% than RH =60%(the mean value of ΔT, ΔT fd), for the tree(z =1.5m): ΔT fd is -5.4°C (-1.4∼-1.5°C) at RH =0%/60%. 4)At RH =60%, both shrubs and trees exhibit a notable warming phenomenon near the vegetation canopies tops(ΔT Max =1.3°C/0.9°C for shrubs/trees). This study provides and confirms a reliable numerical method for simulating the interactions of vegetation transpiration and other physical processes in urban or rural areas. [Display omitted] [ABSTRACT FROM AUTHOR]

• Understory shrubs had earlier spring leaf phenology than canopy trees. • Warming advanced the spring leaf phenology for both shrubs and trees. • Shading delayed the bud burst and leaf unfolding of trees and the bud burst of shrubs. • Spring leaf phenology of trees was more sensitive to temperature than that of shrubs. • Bud burst of shrubs was slightly more sensitive to light intensity than that of trees. Spring leaf phenology influences plant fitness and is highly sensitive to environmental changes. The spring phenological escape hypothesis posits that deciduous understory plants generally leaf out earlier than canopy trees to access a period of high light before the canopy closes. However, plants in different forest layers may respond differently to climate warming, which could lead to phenological mismatch between the understory and canopy species. Therefore, exploring the phenological sensitivities of plants from different forest layers is crucial for anticipating the effects of climate-driven phenological shifts. However, these types of studies are still scarce. Here, we conducted a twig experiment in climate chambers for eight tree species and seven shrub species growing in subtropical deciduous forests in the Shennongjia Mountains, central China. Specifically, we set up three treatments (control, warming, and shading) for five weeks to test the responses of the timing of bud burst and leaf unfolding, and the duration of bud development to different temperatures and light intensities. For shrubs, bud burst and leaf unfolding occurred earlier and the duration of bud development was shorter than these of trees. For both shrubs and trees, warming significantly advanced the timing of leaf unfolding and shortened the duration of bud development. Shading significantly delayed the timing of bud burst for both shrubs and trees. Shading also delayed the timing of leaf unfolding and lengthened the duration of bud development for trees, but did not significantly influence the two phenological metrics for shrubs. Tree phenology, as measured by all three metrics, was more sensitive to temperature than was shrub phenology. The timing of bud burst of shrubs was slightly more sensitive to light than that of trees. Our results indicate that shrubs leaf out earlier than trees in the same forest, which allows understory species to take advantage of the high-light resources before canopy closure. However, in our study, trees were more responsive to warming temperatures, suggesting that spring warming could advance canopy closure relative to shrub leaf phenology, potentially resulting in phenological mismatch between understory shrubs and canopy trees. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose. The study aims to (i) discover the various trees and shrubs appropriate for building agroforestry systems in Bulgaria’s temperate climate and their possible use in various economic activities, (ii) identify the contribution of Bulgarians’ agroforestry systems to the three dimensions of sustainable development. Results. The contributions of Bulgarians’ agroforestry systems to three pillars of sustainability were pointed out. Regarding the social dimension of sustainability, the respondents highlighted the social benefits of agroforestry (e.g., raising the standard of living and the social status of the population; providing jobs and access to renewable energy; overcoming social inequality in individual regions; providing recreation opportunities for the population; give social, educational, scientific, landscape and recreational benefits to society; generate firewood for society). The contribution of agroforestry in the environmental dimension is unquestionable. Moreover, 46 trees and 15 shrubs have been presented. The use of their products in various economic activities and industries has been discussed. These trees and shrubs are appropriate for the construction of various agroforestry systems such as forest-farming, alley-cropping, and forest-pasture agroforestry systems. Scientific novelty. A few scientific researches focus on tree species suitable for agroforestry systems in particular counties with different climates. However, there is limited research on various trees and shrubs suitable for constructing agroforestry systems in a temperate climate, especially in Bulgaria. Moreover, the use of the products of these trees and shrubs in various economic sectors and activities, which can bring additional economic value for agroforestry farmers in temperate climates, is not discussed in one paper. Practical value. The current findings will provide farmers with additional knowledge about trees and shrubs suitable for the construction of agroforestry systems in temperate climates and the possible implementation of their products in various economic activities and industries. This will encourage them to create ecoefficient agroforestry systems using some of the 46 trees and 15 shrubs, based on their regional location and local conditions, to support sustainable development and the environment. What is more, if these tree species are promoted by decision-makers and professional/farmer associations, and adopted by the farmers can support and reinforce agroforestry in Bulgaria and regions with temperate climates.

Chlorophyll a fluorescence (ChF) signal analysis has become a widely used and rapid, non-invasive technique to study the photosynthetic process under stress conditions. It monitors plant responses to various environmental factors affecting plants under experimental and field conditions. Thus, it enables extensive research in ecology and benefits forestry, agriculture, horticulture, and arboriculture. Woody plants, especially trees, as organisms with a considerable life span, have a different life strategy than herbaceous plants and show more complex responses to stress. The range of changes in photosynthetic efficiency of trees depends on their age, ontogeny, species-specific characteristics, and acclimation ability. This review compiles the results of the most commonly used ChF techniques at the foliar scale. We describe the results of experimental studies to identify stress factors that affect photosynthetic efficiency and analyse the experience of assessing tree vigour in natural and human-modified environments. We discuss both the circumstances under which ChF can be successfully used to assess woody plant health and the ChF parameters that can be useful in field research. Finally, we summarise the advantages and limitations of the ChF method in research on trees, shrubs, and woody vines.