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Background and Aims: Herbaria were recently advertised as reliable sources of information regarding historical changes in plant traits and biotic interactions. To justify the use of herbaria in global change research, we asked whether the characteristics of herbarium specimens have changed during the past centuries and whether these changes were due to shifts in plant collection practices., Methods: We measured nine characteristics from 515 herbarium specimens of common European trees and large shrubs collected from 1558 to 2016. We asked botanists to rank these specimens by their scientific quality, and asked artists to rank these specimens by their beauty., Key Results: Eight of 11 assessed characteristics of herbarium specimens changed significantly during the study period. The average number of leaves in plant specimens increased 3-fold, whereas the quality of specimen preparation decreased. Leaf size negatively correlated with leaf number in specimens in both among-species and within-species analyses. The proportion of herbarium sheets containing plant reproductive structures peaked in the 1850s. The scientific value of herbarium specimens increased until the 1700s, but then did not change, whereas their aesthetic value showed no systematic trends., Conclusions: Our findings strongly support the hypothesis that many characteristics of herbarium specimens have changed systematically and substantially from the 16th to 21st centuries due to changes in plant collection and preservation practices. These changes may both create patterns which could be erroneously attributed to environmental changes and obscure historical trends in plant traits. The utmost care ought to be taken to guard against the possibility of misinterpretation of data obtained from herbarium specimens. We recommend that directional changes in characters of herbarium specimens which occurred during the past 150‒200 years, primarily in specimen size and in the presence of reproductive structures, are accounted for when searching for the effects of past environmental changes on plant traits., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Annals of Botany Company.)

Composed of a naked circular non-protein-coding genomic RNA, counting only a few hundred nucleotides, viroids-the smallest infectious agents known so far-are able to replicate and move systemically in herbaceous and woody host plants, which concomitantly may develop specific diseases or remain symptomless. Several viroids have been reported to naturally infect pome and stone fruit trees, showing symptoms on leaves, fruits and/or bark. However, Koch's postulates required for establishing on firm grounds the viroid etiology of these diseases, have not been met in all instances. Here, pome and stone fruit tree diseases, conclusively proven to be caused by viroids, are reviewed, and the need to pay closer attention to fulfilling Koch's postulates is emphasized.

Fast-growing metal-accumulating woody plants are considered potential candidates for phytoremediation of metals. Tonglushan mining, one of the biggest Cu production bases in China, presents an important source of the pollution of environment. The sample was collected at Tonglushan ancient copper spoil heap. The aims were to measure the content of heavy metal in the soil and woody plants and to elucidate the phytoremediation potential of the plants. The result showed that soil Cu, Cd and Pb were the main contamination, the mean contents of which were 3166.73 mg/kg, 3.66 mg/kg and 137.06 mg/kg respectively, which belonged to severe contamination. Fourteen species from 14 genera of 13 families were collected and investigated; except for Ligutrum lucidum, the other 13 woody plants species were newly recorded in this area. In addition, to assess the ability of metal accumulation of these trees, we proposed accumulation index. Data suggested that Platanus × acerilolia, Broussonetia papyrifera, Ligutrum lucidum, Viburnum awabuki, Firmiana simplex, Robina pseudoacacia, Melia azedarach and Osmanthus fragrans exhibited high accumulated capacity and strong tolerance to heavy metals. Therefore, Platanus × acerilolia and Broussonetia papyrifera can be planted in Pb contaminated areas; Viburnum awabuki, Firmiana simplex, Robina pseudoacacia and Melia azedarach are the suitable trees for Cd contaminated areas; Viburnum awabuki, Melia azedarach, Ligutrum lucidum, Firmiana simplex, Osmanthus fragrans and Robina pseudoacacia are appropriate to Cu, Pb and Cd multi-metal contaminated areas.

Elucidating symbiotic relationships between arbuscular mycorrhizal fungi (AMF) and plants contributes to a better understanding of their reciprocally dependent coexistence and community assembly. However, the main drivers of plant and AMF community assembly remain unclear. In this study, we examined AMF communities from 166 root samples of 17 woody plant species from 10 quadrats in a Chinese subtropical forest using 454 pyrosequencing of 18S rRNA gene to describe symbiotic AMF-plant association. Our results show the woody plant-AMF networks to be highly interconnected and nested, but in antimodular and antispecialized manners. The nonrandom pattern in the woody plant-AMF network was explained by plant and AMF phylogenies, with a tendency for a stronger phylogenetic signal by plant than AMF phylogeny. This study suggests that the phylogenetic niche conservatism in woody plants and their AMF symbionts could contribute to interdependent AMF and plant community assembly in this subtropical forest ecosystem., (© 2017 John Wiley & Sons Ltd.)

The existing scenarios generally predict that herbivory will increase with climate warming. An analysis of the published data on the background foliar losses of woody plants to insects in natural ecosystems across the globe from 1952 to 2013 provided no support for this hypothesis. We detected no temporal trend in herbivory within the temperate climate zone and a significant decrease in herbivory in the tropics. From 1964 to 1990, herbivory in the tropics was 39% higher than in the temperate region, but these differences disappeared by the beginning of the 2000s. Thus, environmental changes have already disturbed one of the global ecological patterns--the decrease in herbivory with latitude--by affecting ecosystem processes differently in tropical and temperate climate zones., (© 2015 The Author(s) Published by the Royal Society. All rights reserved.)

The associations of arbuscular mycorrhizal (AM) or ectomycorrhiza (EcM) fungi with plants have sequentially evolved and significantly contributed to enhancing plant nutrition. Nonetheless, how evolutionary and ecological forces drive nutrient acquisition strategies of AM and EcM woody plants remains poorly understood. Our global analysis of woody species revealed that, over divergence time, AM woody plants evolved faster nitrogen mineralization rates without changes in nitrogen resorption. However, EcM woody plants exhibited an increase in nitrogen mineralization but a decrease in nitrogen resorption, indicating a shift towards a more inorganic nutrient economy. Despite this alteration, when evaluating present‐day woody species, AM woody plants still display faster nitrogen mineralization and lower nitrogen resorption than EcM woody plants. This inorganic nutrient economy allows AM woody plants to thrive in warm environments with a faster litter decomposition rate. Our findings indicate that the global pattern of nutrient acquisition strategies in mycorrhizal plants is shaped by the interplay between phylogeny and climate. [ABSTRACT FROM AUTHOR]

People's daily life is unimaginable without plants vegetations. Since ancient times, plants have provided human beings with some kinds of needs – they feed, train, heal, provide shelter, delight the eye, and decorate the environment. It is proposed to grow woody plants mentioned in the Bible and introduced in Lithuania in churchyards. Plants mentioned in the Bible that cannot be grown in Lithuania can be replaced with similar visual, ecological and biological properties. It is proposed to put information about the plant and a text from the Bible next to the plants. The most common small architectural structures in churchyards are crosses, chapels, shrines, chapel columns, decorative pools, sculptures of saints, stations of the cross, tombstones, fences, notice boards, lourdes, nativity scenes for Christmas. By using different environmental design tools, it is possible to create church churchyards as Bible gardens. [ABSTRACT FROM AUTHOR]

Facilitative interactions between shrub and animal species influence the structure and composition of communities. The benefits associated with woody shrub species can critically influence local animal populations, in particular. Here, we tested the relative importance of the density of shrub species on the local abundance of animal populations using a meta‐analysis. Full‐text review for shrub density, animal abundance or density and sampling effort, resulted in a total of 113 independent observations that reported both shrub density and animal abundance. A meta‐regression of shrub density on animal density with feeding functional group of the animal species as a moderator was used to test the predictive capacity of this simple vegetation measure on animal populations. Shrub density positively predicted animal abundance in these studies – particularly in deserts and grasslands. Shrub and woody plant density can thus be used as a potential rapid proxy for habitat in predicting local animal abundances. This method can support restoration and conservation of resident animal species in impacted ecosystems structured by woody shrubs globally. [ABSTRACT FROM AUTHOR]

Aim: After colonising isolated islands, many types of plants and animals undergo extreme morphological diversification. In stark contrast, other island taxa change more subtly and converge evolutionarily on intermediate body size (the island rule). This paradox of island evolution has gone undetected for decades, perhaps because each pattern has been investigated separately using different analytical tools. Here, I investigate the paradox of island evolution in the endemic floras of four oceanic archipelagos in the Southwest Pacific. Location: Chatham, Kermadec, Lord Howe & Norfolk Islands. Taxon: Woody plants. Methods: I test whether the sizes of 'solitary endemics' (species that evolved anagenetically in the absence of co‐occurring endemic congeners) are correlated with their closest mainland ancestors. I also test whether island–mainland size relationships in 'solitary endemics' differ from isometry, as predicted by the island rule. Next, I test whether the stature of 'co‐occurring endemics' (closely related, often cladogenetic species) exhibits exaggerated differentiation. Results: The stature of 'solitary endemics' was correlated with their mainland relatives, and two out of the four archipelagos showed evidence of the island rule. On the other hand, the stature of 'co‐occurring endemics' was unrelated to their closest mainland relatives and often highly differentiated. Main conclusions: Overall results suggest that the island paradox arises from two distinct evolutionary pathways. Solitary endemics evolve more slowly and often converge on intermediate morphology, while co‐occurring endemics evolve more rapidly and often exhibit highly differentiated morphology. Future work aimed at a better understanding of the mechanisms underpinning the island paradox could help to further unite phylogenetic work on adaptive radiations and macroecological tests of the island rule under a single conceptual umbrella. [ABSTRACT FROM AUTHOR]

Summary: Consistent information on the current elemental composition of vegetation at global scale and the variables that determine it is lacking.To fill this gap, we gathered a total of 30 912 georeferenced records on woody plants foliar concentrations of nitrogen (N), phosphorus (P) and potassium (K) from published databases, and produced global maps of foliar N, P and K concentrations for woody plants using neural networks at a resolution of 1 km2. We used data for climate, atmospheric deposition, soil and morphoclimatic groups to train the neural networks.Foliar N, P and K do not follow clear global latitudinal patterns but are consistent with the hypothesis of soil substrate age. We additionally built generalized linear mixed models to investigate the evolutionary history effect together with the effects of environmental effects. In this comparison, evolutionary history effects explained most of the variability in all cases (mostly > 60%).These results emphasize the determinant role of evolutionary history in foliar elemental composition, which should be incorporated in upcoming dynamic global vegetation models. [ABSTRACT FROM AUTHOR]

Summary: Many plant movements are facilitated by contractile cells called gelatinous fibers (G‐fibers), but how G‐fibers function in the climbing movements of woody vines remains underexplored. In this Insight, we compare the presence and distribution of G‐fibers in the stems of stem‐twiners, which wrap around supports, with non‐stem‐twiners, which attach to supports via tendrils or adventitious roots. An examination of 164 species spanning the vascular plant phylogeny reveals that G‐fibers are common in stem‐twiners but scarce in non‐stem‐twiners, suggesting that G‐fibers are preferentially formed in the organ responsible for movement. When present, G‐fibers are in the xylem, phloem, pericycle, and/or cortex. We discuss the hypothesis that G‐fibers are foundational to plant movement and highlight research opportunities concerning G‐fiber development and function. [ABSTRACT FROM AUTHOR]

Construction of dams in the mid‐20th century reduced channel dynamism, sediment transport, and regeneration of riparian trees on the Missouri River. Opportunities for forest regeneration, however, may occur where the Missouri River or tributaries deposit sediments in reservoir headwaters, forming deltaic and associated upstream backwater areas. One such delta‐backwater occurs at the confluence of the Niobrara and Missouri rivers upstream from Lewis and Clark Lake in southeastern South Dakota and northeastern Nebraska. We investigated spatiotemporal patterns of tree recruitment through vegetation sampling in 2017–2018, dendrochronology, and analysis of aerial photography from 2006 to 2016. We sampled woody vegetation in 47 plots and took tree‐ring samples from one to two trees within each plot to determine establishment dates. Woody vegetation was dominated by Populus deltoides (cottonwood) and Salix amygdaloides (peachleaf willow) in the tree layer and Salix interior (sandbar willow) in the shrub layer. Tree establishment occurred primarily in 2010–2012 and was distributed throughout the study area, including at the delta‐reservoir interface. LiDAR data showed that most of the delta‐backwater experienced a 0.5‐m increase in elevation in 2005–2011, a period that included high flows in 2010 on the Niobrara River and 2011 on the Missouri River. Woody vegetation decreased 8% from 2006 to 2012, but doubled from 2012 to 2016, colonizing areas of previous sandbar and herbaceous vegetation. These woodlands represent early successional habitat that is in decline elsewhere along the river. Understanding vegetation dynamics within reservoir delta‐backwaters may be vital for forecasting changes in regulated riverine landscapes, assessing biodiversity values of these ecosystems, and informing sustainable reservoir management. [ABSTRACT FROM AUTHOR]

Premise: To support large leaves, many woody plant species evolved a cost‐effective way to thicken twigs. As an extension of E. J. H. Corner's rule that twig diameter increases with leaf size, we hypothesized that pith width also increases with leaf size. The benefit to the plant from the proposed relationship is that pith is a low‐cost tissue that reduces the metabolic cost of large diameter twig production. Methods: Leaf sizes and cross‐sectional areas of bark, xylem, and pith of 81 species of trees and shrubs growing in Gainesville, Florida were measured and compared with standardized major axis regressions of pairwise species trait values and phylogenetically independent contrasts. Results: Pith area increases with leaf size with or without accounting for phylogenetic relationships. In agreement with Corner's rule, overall twig diameter as well as bark and wood thickness also increase with leaf size. Thicker twigs showed more variation in relative pith, wood, and bark cross‐sectional areas compared to thinner twigs. Conclusions: Investments in pith, a tissue of low density found in the centers of twigs, provides a low‐cost way to increase twig circumference and thereby space for attachment of large leaves while increasing the overall second moment of area of twigs, which increases their ability to biomechanically support large leaves. [ABSTRACT FROM AUTHOR]

Relaxing in the shade of a tree, enjoying its fragrance, the oxygen offered as a gift, the refuge it offers, gives all the measure of the wealth of trees. An individual good, a collective wealth, the tree has a value attributable to the functions it performs. Whether the tree is young or centuries-old, it is directly or indirectly influenced by people, which is why it is important to appreciate its value. This is why it is necessary to assess the financial value of ornamental trees and estimate the amount of compensation in the event of damage. The chosen research topic is carried out in Buzău, on the domain of Alexandru Marghiloman. He built for his wife a wonderful tree park, which has become public today, on an area of 16,000 square meters. To date, there is no single reference assessment scale unanimously recognized by communities, experts, insurance companies and the judiciary. The B.E.V.A. method - the Tree Value Assessment Scale created in France (Barème dEvaluation de la Valeur dun Arbre) (or the method of large cities in France) - was used to evaluate the trees in Marghiloman Park. B.E.V.A. is used to calculate the value of a tree in an urban landscape or road alignment based on 4 criteria (species, girth, health, aesthetic value). The results have been registered and are part of the green inventory of this park. [ABSTRACT FROM AUTHOR]

Restoration and rehabilitation are globally implemented to improve ecosystem condition but often without tracking treatment expenditures relative to ecological outcomes. We evaluated the cost‐effectiveness of widely conducted woody plant and herbaceous invasive plant removals and seeding treatments in drylands of the western United States from 2004 to 2018 to determine how land managers can optimize efforts. Woody plant cover decreased at a similar rate per dollar spent regardless of vegetation removal type, and the dominant invasive species was reduced by herbicide application. Relatively inexpensive herbicide application also had a large positive effect on seeded perennial grass cover that was enhanced by additional cost; while expensive woody mastication treatments had little effect regardless of additional cost. High seed cost was driven by including a large proportion of native species in seed mixes, and combined with high seeding cost, promoted a short‐term (2–3 yr) gain in perennial forb cover and species richness. In contrast, seeding and seed mix cost had no bearing on seeded perennial grass cover, in part, because relatively cheap nonnative seeded species rapidly increased in cover. Our results suggest the differential benefits of commonly implemented treatments aimed at reducing wildfire risk, improving wildlife habitat and forage, and reducing erosion. Given the growing need and cost of restoration and rehabilitation, we raise the importance of specifying treatment budgets and objectives, coupled with effectiveness monitoring, to improve future outcomes. [ABSTRACT FROM AUTHOR]

Aims Litterfall at a global scale is affected by climate, edaphic features and vegetation structure, with litter production increasing from grasslands to forests following the rise in standing biomass. However, at landscape scales, the same relationship between litter production and vegetation structure has rarely been studied and comparisons of litterfall patterns between adjacent, structurally distinct communities are lacking. Here, we use a standardized methodology to describe the structural differences among four savanna physiognomies and analyze their relationship with changes in litterfall across the Cerrado. Methods We evaluated the woody vegetation structure and composition in 48 sites, equally distributed across four physiognomies and monitored the monthly litter production from April 2014 to March 2015. Important Findings Results showed that the density, basal area, cylindrical volume and aboveground biomass of woody vegetation differ among physiognomies, increasing consistently from cerrado ralo , cerrado típico , cerrado denso and cerradão. Indeed, we found a strong and positive relationship between aboveground biomass and annual litter production, with litter yield increasing from 0.9 to 8.4 Mg ha−1 across different physiognomies, following the increment in vegetation structure. Monthly production was seasonal and similar among vegetation types, increasing during the dry season. Leaves comprised the dominant fraction (approx. 85%) and litterfall seasonality primarily resulted from the concentration of leaf shedding during dry months. However, the temporal pattern of litterfall throughout the year showed a gradual reduction in the seasonality from open to closed vegetation types, likely following the decrease of deciduous species abundance in the plant community. Our results showed that changes in vegetation structure may affect spatial and temporal litterfall patterns in different physiognomies, which co-occur across the Cerrado landscape, with potential implications for the overall functioning of this ecosystem. Moreover, these findings highlight the use of standardized methods as essential to correctly compare litterfall patterns among different environments. [ABSTRACT FROM AUTHOR]

The considerable interest in detecting global vegetation changes based on satellite observations is increasing. However, studies rely on single indices to explore the driving mechanisms of the greening trend might exacerbate uncertainties of global ecosystem change. Thus, vegetation growth dynamics from various biophysical properties required to be monitored comprehensively. In this study, a consistent framework for evaluating vegetation growth trends was developed based on five widely used satellite‐derived products of MODIS Collection 6; the consistency in vegetation growth was mapped; and the factors that affected the consistency of vegetation growth were explored. The results showed that, during 2000‐2015, 45.6% of global vegetated area experienced inconsistent trends in vegetation greenness, cover and productivity, especially in evergreen broadleaf forests, grasslands, open shrublands, woody savannas and croplands. Only 5.4% of global vegetated area exhibited simultaneous trends in greenness, cover and productivity, and the inconsistent areas were expanding in the study period. Contradictory vegetation changes were mainly reflected in the opposite trends of vegetation greenness and productivity in evergreen broadleaf forests. Moreover, the inconsistency change was mainly manifested in the greenness‐dominated vegetation enhancement, without enhanced productivity. The increment difference between NPP and GPP also showed respiration losses greatly offset the effect of vegetation greenness or cover on productivity. This study provides integrated insights for understanding the inconsistency of vegetation structural and functional changes in the context of global greening. Plain Language Summary: Terrestrial vegetation dynamics are extremely important to global environmental change and have consequences for the functioning of the Earth system and provisioning of ecosystem services. Recent greening of the global terrestrial ecosystems suggested an increasing trend in vegetation growth. However, different vegetation properties that were described by indices have not been comprehensively compared. In this study, a consistent framework for evaluating vegetation growth trends was developed based on five widely used satellite‐derived vegetation indices; the consistency in vegetation growth was mapped; and the factors that affected the consistency of vegetation growth were explored. We found that during 2000–2015, nearly half of global vegetated area experienced inconsistent trends in vegetation greenness, cover, and productivity, especially in evergreen broadleaf forests. The vegetation inconsistent change was manifested in the greenness‐dominated vegetation enhancement, but the productivity did not enhance. Relationship between vegetation cover and productivity was higher than that between vegetation greenness and productivity. It was also found that respiration losses greatly offset the effect of vegetation greenness or cover on productivity. This study provides integrated insights into vegetation growth trends, interpreting inconsistency of vegetation structural and functional changes in the context of global greening. Key Points: Nearly half of global vegetated area experienced inconsistent vegetation trendsInconsistency was manifested as the greenness and non‐productivity enhancementVegetation types differed in the greenness, cover, and productivity trends [ABSTRACT FROM AUTHOR]

Summary: Droughts and land degradation result in biodiversity and ecosystem service losses with serious implications for human wellbeing. The Sahel region has seen increased plant cover since the end of 1970s–1980s droughts, but understanding the nature and implications of this change remains a priority. This study aimed to assess changes in the woody floristic composition of re-greened agrosystems since the droughts in Burkina Faso. In 148 vegetation survey plots distributed across areas with increasing woody plant cover and those to some extent protected from exploitation, a total of 71 species from 51 genera and 23 families were identified. Compared to pre-drought flora, our measurements show a decline in the diversity and density of woody species. Combretaceae species and thorny species of the genera Acacia and Balanites, which are more tolerant of drought, were the most dominant, indicating a post-drought woody vegetation that is more resistant to water stress. The increased presence of food-producing species in agroforestry parks (cultivated fields with woody plants) seems to reflect the growing needs of the human population. [ABSTRACT FROM AUTHOR]

The phenomenon of sharp boundaries between distinctive vegetation types occurring under the same climatic conditions has often been interpreted by plant ecologists to characterise alternative stable states (ASS). The phenomenon may be relevant in explaining two strikingly different vegetation formations (broad‐leaved nonspiny Combretum and fine‐leaved spiny Acacia) co‐occurring in mesic savannah of southeastern Kenya. We hypothesise that the two vegetation within southeastern Kenya ecosystems represent ASS whose transition may be a response to soil characteristics switch. To explore our hypothesis, we analysed empirical field data of woody species and soil characteristics from 57 plots that included 25 from Combretum and 32 from Acacia vegetation formations. We compared floristic composition and soil characteristics between the two systems and correlated edaphic statuses and vegetation states. We encountered 2,749 woody plant individuals, representing 115 species, 87 genera and 40 families. We found that the two vegetation had discrete woody species composition and soil characteristics, and also a significant species–edaphic association. The results are consistent with the ASS theory demonstrating that soil characteristics are among the important micro‐environmental filters driving and maintaining woody vegetation mosaics in the tropics. Importantly, understanding ASS has ramifications for sustainable utilisation of woody plant resources in East African savannahs. [ABSTRACT FROM AUTHOR]

Phytophthora pseudocryptogea, a member of clade 8a of the Phytophthora phylogenetic tree, was formally described in 2015 as a close relative of P. cryptogea and P. erythroseptica. The potential host range of this newly described species and its close relatives was investigated in this study. Thirty species of herbaceous plants and nine species of woody plants were inoculated and monitored for development of foliar symptoms and root rots. Also, we inoculated the detached twigs of 21 tree species, fruit of six plant species, tubers of potato, and roots of carrot and sugar beet. Our results showed P. pseudocryptogea, P. cryptogea and P. erythroseptica had different potential host ranges, though all were pathogenic on some plant species such as pistachio, tomato, potato, eggplant, spinach and clover. Additionally, some plant species were able to discriminate P. pseudocryptogea from P. cryptogea including cucumber, melon, watermelon, alfalfa, soybean, cabbage, green pepper, and rice. These plants showed susceptibility to P. pseudocryptogea and resistance to P. cryptogea. Different species showed different virulence levels on detached tree twigs; however, almost all species caused severe rot on all tested fruits, tubers and roots. Investigation of the effects of root-zone temperature on the virulence of species showed that a temperature of 20 °C in increased root rot and root colonization in P. pseudocryptogea and P. erythroseptica, while P. cryptogea caused the most root rot and colonization at 25 °C. [ABSTRACT FROM AUTHOR]

Questions: Can co‐occurrence and phylogenetic resemblance of taxa in plots be integrated into a single composite numerical framework so that vegetation classification expresses both in a unique system? How should phylogenetic similarity of vicariant taxa, in synvicariant communities, be dealt with for use in vegetation classifications? Is this meaningful to Vegetation Science and Biogeography? Is Macaronesia's woody vegetation an adequate paradigm to test a methodological workflow for phylogenetically informed classification? Location: Macaronesia: the Azores, Madeira, Canaries, and Cape Verde archipelagos. Methods: We used both (a) co‐occurrence‐only and (b) phylogenetic Bray–Curtis similarity indexes in straightforward classification algorithms: Ward's method clustering and isopam divisive classification. Phylogenetic distances for (b) were taken from an ad hoc phylogenetic tree. The tree was obtained by grafting/pruning subtrees from DNA sequence alignments of rcbL, ITS and matK into a subset of an available megaphylogeny. Results: Co‐occurrence‐only similarity is not a reliable predictor of phylogenetic similarity. Two distinct approaches to similarity imply significant differences in classifications. As groups in both classifications may be equated to woody‐vegetation classes, alternative arrangements of such will appear. Vegetation classes are quasi‐specific to each archipelago if accounting for co‐occurrence‐only. Conversely, larger units spanning several archipelagos emerge when phylogeny is considered. Conclusion: We recognise the usefulness of incorporating phylogeny in the definition of formal vegetation units so that the concept of syntaxon may include it. Supra‐class units issuing from phylogenetically informed similarity originate, for the most, from vegetation synvicariance rather than from sharing of species. Therefore, these units correspond preferably to biogeographical concepts (phytochoria), not to phytocoenological units. Regarding "Macaronesia" being a consistent biogeographical unit, if compositional and ecological vegetation patterns are preferred, we support the separation of Macaronesia in several biomes and thus into several Regions within two Kingdoms. Contrariwise, if common ancestry of taxa and synvicariance in syntaxa is to be emphasised, then the one‐Macaronesia Region model re‐appears. [ABSTRACT FROM AUTHOR]

This study was carried out in the northern region of Burkina Faso under Sahelian climatic conditions. The area was particularly affected by the 1970s–1980s droughts that led to the degradation of land and vegetation. Since the early 1990s, a gradual return of rainfall has been observed throughout the Sahel region. In this new environmental context, understanding the development of woody plants is important for effective conservation and management. We analyzed the dynamics of woody plant cover over the 30 years following the end of the 1970s–1980s droughts by using Landsat images from 1986, 1999, and 2015 with 30 m spatial resolution and taking into account changes in rainfall and land use. The change in the enhanced vegetation index 1 (EVI1) at the beginning of the dry season was used as a proxy for the change in photosynthetic activity of woody plants. Results showed an improvement in EVI1 on 98% of the study area, with a mean increase of 0.20 from 1986 to 2015. This improvement was accompanied by an increase in agroforestry and was weakly correlated with rainfall. The improvement in EVI1 was unstable, however, with a decline from 1999 to 2015 in the areas undergoing regreening. [ABSTRACT FROM AUTHOR]

This study considers the restoration of the plant cover destroyed by a catastrophic volcano eruption in the south of Kamchatka Peninsula (the Ksudach caldera, Shtyubel cone), with a particular attention to the role of woody plants. It aims to qualitatively estimate (at a qualitative level) the rate of the primary succession development depending on the microrelief and the modern relief-forming processes. The vegetation recovery in the caldera after the Shtyubel cone eruption 109 years ago proceeds slowly and irregularly. It proceeds most slowly on a thick tephra mantle continuously disturbed by water and wind erosion, lahars, debris flows, landslides, etc. Such conditions are most typical of the western part of the caldera dominated by pumice fields with occasional patches of pioneer herbs and dwarf shrubs. Alpine tundra communities with gradually expanding patches of shrub alder develop in the southern, eastern and northeastern parts of the Ksudach caldera. Since 1997 the area of the shrub alder communities has increased by 1.9 times, while the alpine tundra — by 1.3 times only. The woody plants (dwarf shrubs and prostrate shrubs) are of particular importance in the process of the vegetation recovery on pumice fields. We suggest that the bark thickness of woody plants is an integrated indicator, which may serve for estimating the state of ecosystem in the course of the primary succession development on juvenile sediments. The extremely inhospitable environments cause changes in physiological processes in the plant body and in its bark in particular. The results show that woody plants have a "thin" bark and develop some structural-functional arrangements for keeping bark tissues at their minimum. So, the woody plant structure and the rate of changes in plant communities are under control of the geomorphic conditions and primarily — of physicochemical features of the pyroclastic cover. [ABSTRACT FROM AUTHOR]

This study was conducted in Agama Forest in Kafa Zone, Southwestern Ethiopia, to assess species diversity, vegetation structure, and regeneration status of woody species. A systematic sampling technique was employed to collect vegetation data. Sixty (60) sample plots of 25 m × 25 m were laid at 300 m intervals all along ten grids interspaced 800 m apart. Sample plots of 25 m × 25 m were used to record DBH and H of all woody plant species reaching a DBH >2.5 cm and height >2 m. For the inventory of seedling and sapling, two subplots of 2 m × 5 m were used at the beginning and the end of the baseline on opposite sides of the main quadrat. Vegetation data such as DBH, height, seedling, and sapling density of woody species were recorded in each plot. Altogether, 72 woody plant species of 65 genera and 35 families were identified. Analysis of selected tree species showed diverse population structures. This study showed that small trees and shrubs dominated the Agama Forest, which revealed its status under a secondary regeneration stage. Study on the structure and regeneration of some woody species indicated that there are species that require urgent conservation measures. Sound management and monitoring, as well as maintenance of biodiversity and cultural and economic values of the forest, require conservation activities that encourage sustainable uses of the forest and its products. [ABSTRACT FROM AUTHOR]

Plants were regenerated from in vitro leaf and petiole tissues of Rubus spp. L. (red raspberry) 'Joan J' and 'Polana' in woody plant medium (WPM), with 200 mg L−1 polyvinylpyrrolidone (PVP), and various combinations of 6-benzylaminopurine (BA) and/or thidiazuron (TDZ). The effects of explant type and explant age on plant regeneration were also investigated. Results showed that the regeneration rates were 70% for 'Joan J' and 82.2% for 'Polana,' when 7-d-old leaf tissues were inoculated on WPM with 2.5 μM BA + 1.0 μM TDZ and WPM with 2.5 μM BA + 0.1 μM TDZ, respectively. For 'Joan J,' in vitro rooting was readily achieved (100%) in one-half Murashige and Skoog (MS) medium supplemented with 10 μM 1-naphthaleneacetic acid (NAA). For 'Polana,' a rooting rate of 75% was achieved when cuttings were pulsed in one-half MS with 20 μM NAA for 7 d and then transferred to auxin-free one-half MS medium. An efficient ex vitro rooting frequency (> 80%) was obtained for both cultivars when cuttings were quickly dipped in 500 μM Indole-3-burytic acid (IBA) or NAA, and inserted to Sunshine Mix no. 1 (Fisons Western Corp., Vancouver, Canada) for a 4-wk rooting and acclimatization period. Regenerated plants were eventually grown in the greenhouse. This research will assist germplasm improvement using biotechnology techniques for raspberries and other Rubus species. [ABSTRACT FROM AUTHOR]

Biodeterioration, the alteration caused by living organisms, on historical buildings and stone monuments is a well-known problem affecting two-thirds of the world's cultural heritage. The study of the flora growing on wall surface is of particular importance for the assessment of the risk of biodeterioration of stone artifacts by vascular plants, and for maintenance planning. In this study, we investigate how rock type, exposure and inclination of the wall affect the biodeteriogenic flora at 13 sites of the Archaeological Park of the Phlegraean Fields located in the province of Naples, in southern Italy. For each site, we analysed randomly selected square areas with 2 × 2 m size, representing the different vegetation types in terms of vascular plant species cover. The total number of plant species recorded was 129, belonging to 43 families. Erigeron sumatrensis, Sonchus tenerrimus and Parietaria judaica are the most commonly reported species, while Capparis orientalis is the species with the highest average coverage. Substrate type, exposure and surface inclination affect the floristic composition, with the average plant cover significantly higher on vertical surfaces and at western and southern exposure. All the main biodeteriogenic vascular plant species grow on more or less porous lythotype like yellow tufa, conglomerate and bricks. Finally, woody plants eradications methods are proposed by the tree cutting and local application of herbicides, to avoid stump and root sprouting and to minimize the dispersion of chemicals in the surrounding environment. [ABSTRACT FROM AUTHOR]

New Pliocene macrofloras and microfloras perfectly preserved from the Mont-Dore (Puy-de-Dôme, Massif central, France) have been reinvestigated. Samples come from different stratigraphical levels collected from three localities, Lac Chambon, La Gratade and Pont de Chocol. The 40Ar/39Ar radiometric datings bracketing the Chambon Lake and La Gratade fossil-bearing horizons give 4.46 ± 0.05 Ma and 3.94 ± 0.04 Ma, respectively, representative of the Zanclean Stage (= Brunssumian B and C), a period of the early Pliocene (5.32 to 3.6 Ma), much older than previously thought (i.e., Piacenzian). Pont de Chocol is considered to be close biostratigraphically, or even identical in age to La Gratade. Detailed morphological evaluation of leaf morphotypes completed with pollen analysis contributed to the better taxonomic knowledge of these palaeofloras. The overview focuses on floristic and phytostratigraphical characteristics of the defined stratigraphical units and their dating and correlation with previously defined palaeofloristic units of the Massif central. The study provides detailed identifications of plants representing 11 gymnosperms among which Pinaceae (pollen and winged seeds), Cupressaceae including "Taxodioid" pollen grains and Sciadopitaceae families (only pollen). Besides, different angiosperm trees and shrubs have been determined from both micro- and macro-remains. Fagaceae is the most diversified with several foliage of beech and deciduous oaks, while diversified Juglandaceae contribute mainly as abundant leaf remains of Carya , Pterocarya and Juglans ; Ulmaceae with numerous leave of two Zelkova species, and also Ulmus. Various other deciduous dicotyledonous such as Alnus , Betula , Carpinus , Populus , Acer laetum and A. interrigenum are well documented. Leguminosae are recorded by a small number of leaflet imprints. Evergreen shrubs of Buxaceae (Buxus pliocenica) are scarce. All these taxa contribute to a rich biodiversity of these Pliocene assemblages. All three sites point towards riverine forest habitats dominated by hygrophilic diversified woody plants while in the surrounding plains and slopes the thermophilic elements were scarce and mesophilic taxa abundant as temperate elements. This vegetation can be compared with mixed mesophytic forests depicting a climate cooling during the two considered periods (ca. 4.46 and 3.95 Ma). [ABSTRACT FROM AUTHOR]

14C methods were applied to young, woody, branched and well‐watered cork oak (Quercus suber L.) plants to determine carbon assimilation and its distribution among plant organs. Carbon assimilation rates by attached leaves clamped in a foliar 14CO2 assimilation chamber containing 3.7 × 104 Bq of a portable ventilated diffusion porometer were measured at different 14CO2 pulse‐labeling periods (15, 30, 45, 60 and 120 s) in summer. Allocation of recently fixed C by attached leaves within plants was evaluated 7 days after a 60‐min of 5.6 MBq of 14CO2 pulse‐labeling in late winter. 14CO2 pulse‐labeling was separately induced on leaves of a lower branch, two opposite branches at the same lower level, a middle branch and a top branch. 14C activity incorporated into the plants was measured by liquid scintillation and autoradiography. Our results show the optimum 14CO2 pulse‐labeling period is between 15 and 30 s, which corresponds to 9.81 ± 0.15 and 9.16 ± 0.12 µmol m−2 s−1 C assimilation rates in summer, respectively. The investment of current assimilates ranged from 18 to 29% in leaves, 1 to 7% in lateral branches, 0 to 3% in the stem and over 65% in roots, in late winter. Roots displayed the greatest sink strength for the total 14C recovered by whole‐plants. These results were expected because the trial was done in winter, when cork oak does not produce their leaves. Our results highlight the contribution of current assimilates for growth and maintenance of roots, in young woody plants under Mediterranean climate. [ABSTRACT FROM AUTHOR]

Vegetation natural regeneration after agricultural abandonment is changing the landscape patterns in many areas worldwide. However, the expansion rate, spatio-temporal dynamics, and the role of past vegetation cover in shaping such patterns are still barely quantified in fine and meso scales. Here, we aim to quantify the expansion rate and assess the spatio-temporal patterns and the effects of past cover on natural woody vegetation cover increase. We sampled woodland and shrubland cover from 1992 to 2016 in 30 ha in a formerly managed pastureland in Sicily, Italy. We combined field sampling, GIS tools, and spatial analysis to assess the spatial structure dynamics and test the effects of past cover amount and type and distance from forest or nearest woody patch on the proportional expansion of natural regeneration. After 24 years, woody cover increased 68%, despite the aggregated spatial structure in 1992 remaining almost unchanged in 2016. The past vegetation cover was the best predictor of woody vegetation expansion in two out of three plots. Distance to continuous forest and to the nearest woody patch, as well as cover type, was not relevant. Our study highlights the importance of fine- and meso-scale studies to reveal both the deterministic and stochastic facet of woody vegetation dynamics. Natural regeneration may strongly change landscape patterns even under constant herbivory pressure and long-term deforestation. The detection of cold and hotspots of regeneration provide an important prompt for the design of restoration programs and landscape management. [ABSTRACT FROM AUTHOR]

High levels of sub‐speciation in Australian mesic zone taxa have been attributed to the creation of biogeographic barriers by Pleistocene expansion of the arid zone. However, several of these barriers also align with major floodplains. The Carpentarian Barrier in the Gulf Plains (GUP) – one of Australia's most significant biogeographic barriers – experiences extreme floods on a sub‐decadal timescale. These floods rise suddenly, cover thousands of square kilometres to a depth of several metres and can take weeks to subside. We investigated whether these floods have shaped community composition. If this is the case, species that are particularly vulnerable to extreme flooding – understorey animals and woody plants, particularly shrubs – should be under‐represented, and grasslands should be over‐represented on GUP floodplains. We used Akaike selection of logistic models to assess influence of floodplains and other potential drivers on grassland distribution and shrub abundance, and on representation of understorey fauna. We also compared post‐flood faunal records with the bioregional data set to assess influence of the 2009 flood on representation of understorey reptiles. Grasslands and shrub‐free vegetation were significantly over‐represented and understorey fauna significantly under‐represented on floodplains, even when the influences of other factors were taken into account. Understorey Gekkota were absent from – and understorey skinks under‐represented in – recently flooded areas. Hence, floods appear to have shaped community composition on GUP floodplains by selectively displacing and/or destroying woody plants – particularly shrubs – and understorey animals. Our findings demonstrate association rather than causality, but show that further examination of the ecological and biogeographic impacts of extreme flooding is warranted. Influence of floods on the Australian biota should be considered an ongoing ecological and evolutionary driver, and one that is likely to intensify as extreme floods are expected to become more frequent under climate change. [ABSTRACT FROM AUTHOR]

The study of the critical zones (CZs) of the Earth link the composition and function of aboveground vegetation with the characteristics of the rock layers, providing a new way to study how the unique rock and soil conditions in karst regions affect the aboveground vegetation. Based on survey results of the rocks, soils and vegetation in the dolomite and limestone distribution areas in the karst area of central Guizhou, it was found that woody plant cover increases linearly with the number of cracks with a width of more than 1 mm, while the cover of herbaceous plants shows the opposite trend (p<0.01). The dolomite distribution area is characterized by undeveloped crevices, and the thickness of the soil layer is generally less than 20 cm, which is suitable for the distribution of herbaceous plants with shallow roots. Due to the development of crevices in the limestone distribution area, the soil is deeply distributed through the crevices for the deep roots of trees, which leads to a diversified species composition and a complicated structure in the aboveground vegetation. Based on moderate resolution imaging spectroradiometer (MODIS) remote sensing data from 2001 to 2010, the normalized differentiated vegetation index (NDVI) and annual net primary productivity (NPP) results for each phase of a 16-day interval further indicate that the NDVI of the limestone distribution area is significantly higher than that in the dolomite distribution area, but the average annual NPP is the opposite. The results of this paper indicate that in karst CZs, the lithology determines the structure and distribution of the soil, which further determines the cover of woody and herbaceous plants in the aboveground vegetation. Although the amount of soil in the limestone area may be less than that in the dolomite area, the developed crevice structure is more suitable for the growth of trees with deep roots, and the vegetation activity is strong. At present, the treatment of rocky desertification in karst regions needs to fully consider the rock-soilvegetation- air interactions in karst CZs and propose vegetation restoration measures suitable for different lithologies. [ABSTRACT FROM AUTHOR]

Woody plant cover, the area of the vertical projection of woody plants (trees, shrubs, and bushes), plays an important role in the structure and function of savanna ecosystems and is needed by the savanna modeling community. Recent problems facing savanna ecosystems such as woody plant encroachment and subsequent habitat fragmentation further underscore the relevance of regional-scale and even larger-scale woody plant cover mapping. The mixture of woody plants and herbaceous vegetation in savanna landscapes lends woody plant cover mapping to fractional representation. This study endeavors to develop a simple and reliable approach for fractional woody plant cover mapping in savanna ecosystems. It was tested in the savanna of central Texas, which features a wide woody plant density gradation. A multiple linear regression model was calibrated between orthophoto-based fractional woody plant cover and metrics derived from time series MODIS products of surface reflectance (MOD09A1) and fraction of photosynthetically active radiation (MOD15A2H). By applying this model, woody plant cover was extrapolated to Texas savanna at MODIS scale (500 m). Validation suggests a mean absolute error of 0.098 and an R-squared value of 0.60. This study demonstrates a potential approach for woody plant cover mapping in other savanna ecosystems of the world. It also highlights the utility of time series MODIS products in savanna woody plant cover estimation. [ABSTRACT FROM AUTHOR]

Seed germination traits are key drivers of population dynamics, yet they are under-represented in community ecology studies, which have predominately focussed on adult plant and seed morphological traits. We studied the seed traits and germination strategy of eight woody plant species to investigate regeneration strategies in the arid zone of eastern Australia. To cope with stochastic and minimal rainfall, we predict that arid seeds will either have rapid germination across a wide range of temperatures, improved germination under cooler temperatures, or dormancy and/or longevity traits to delay or stagger germination across time. To understand how temperature affects germination responses, seeds of eight keystone arid species were germinated under laboratory conditions, and under three diurnal temperatures (30/20°C, 25/15°C and 17/7°C) for 30 days. We also tested for decline in seed viability across 24 months in a dry-aging treatment (~20°C). Six of the eight arid species studied had non-dormant, rapidly germinating seeds, and only two species had physiological dormancy traits. Seed longevity differed widely between species, from one recalcitrant species surviving only months in aging (P50 = <3 months) and one serotinous species surviving for many years (P50 = 84 months). Our results highlight the importance of understanding the reproductive strategies of plant species in arid environments. Rapid germination, the dominant seed trait of species included in this study, allows arid species to capitalise on sporadic rainfall. However, some species also exhibit dormancy and delayed germination; this an alternative strategy which spreads the risk of germination failure over time. [ABSTRACT FROM AUTHOR]

Non‐native grasses are frequently sown in the southwestern United States for livestock forage and erosion control. These grasses often spread from areas where they are planted and replace native grasses and forbs. We tested the hypothesis that chestnut‐bellied scaled quail (Callipepla squamata castanogastris) avoid locations dominated by non‐native grasses. We trapped scaled quail at 5 different sites in southern Texas, USA, and located quail fitted with necklace‐style transmitters 3 times/week during 2013–2014. We manually delineated plant communities using aerial maps and on‐the‐ground knowledge of the study sites. We examined second‐order (home‐range scale) selection by comparing proportion of the areas of plant communities within 62 scaled quail home ranges (used) paired with random home ranges (available). We examined third‐order (within‐home‐range scale) selection by comparing the composition of bird location (used) and random (available) points based on proportion of points within plant communities. For both home‐range scale and within‐home‐range scale analyses, we used non‐parametric multivariate analysis of variance with 9,999 random permutations. We examined fourth‐order (organism‐centered) selection by measuring vegetation variables at used and available locations and then estimating the relative probability of use of vegetation variables and by estimating continuous selection functions for variables that were influential in determining relative probability of use. Buffelgrass (Pennisetum ciliare) and Old World bluestems (Bothriochloa spp., Dichanthium annulatum and other Dichanthium spp.) comprised 99% (95% CI = 98–100%, n = 143 sites where non‐native plants occurred) of the non‐native grasses in our study areas. Scaled quail avoided non‐native and riparian plant communities at the home‐range and within‐home‐range scales of selection. At the organism‐centered scale of selection, odds of use by scaled quail decreased 28% for every 10% increase in non‐native grass cover and increased 12% for every 10% increase in shrub canopy cover. Scaled quail avoided locations with >10% canopy cover of non‐native grasses. Based on avoidance at 3 scales of selection, dominance of buffelgrass and Old World bluestems degrades habitat for scaled quail. Spread and sowing of non‐native grasses and brush clearing may be partly responsible for declines in scaled quail populations. © 2019 The Wildlife Society. Chestnut‐bellied scaled quail avoid stands of non‐native grasses and select dense woody vegetation. We recommend managing habitat of this scaled quail subspecies to maintain undisturbed shrubland with >50% woody plant canopy cover and <10% non‐native grass canopy cover. [ABSTRACT FROM AUTHOR]

• MOD44B product shows a strong linear relationship with savanna woody cover. • Potential woody cover has a segmented relationship with rainfall in Texas savanna. • MOD44B can reveal the increasing trend of potential woody cover with rainfall. • MOD44B product lacks year-to-year consistency in Texas savanna. The Moderate Resolution Imaging Spectroradiometer (MODIS) Vegetation Continuous Fields (VCF) tree cover (MOD44B) is an annual product that depicts the fractional coverage of trees on the earth's terrestrial surface at 250m resolution. It has to be noted that the training data of this product is limited to trees above 5 m in height. However, this product has been widely applied in savanna ecosystems where many woody plant species seldom reach 5 m tall. Though the short woody plants in savanna ecosystems could have been reflected in this product due to similar spectral implication as that of tall trees, its applicability has never been rigorously tested. Given so, this study aims to fill this void. It was tested in Texas savanna, which is featured by a wide precipitation gradient and an accompanying woody plant cover gradation. Firstly, we assessed the ability of the MODIS tree cover product in reflecting woody plant cover at pixel level. A per-pixel comparison was conducted between the tree cover values and reference measurement of woody plant cover based on 1-m resolution digital orthophotos. Secondly, we assessed the ability of this tree cover product in reflecting savanna landscape pattern, particularly the potential woody cover pattern over the precipitation gradient in Texas savanna. The MODIS tree cover product based potential woody cover pattern was assessed against the reference pattern of the study area. Thirdly, we assessed the year-to-year consistency of this annual product, under the assumption that tree cover changes very little within one-year period. Reduced major axis regression was conducted between the corresponding tree cover pixels of all successive years from 2000 to 2016. Research results suggest that the MODIS tree cover product has great potential in reflecting woody plant cover at pixel level by empirical calibration. Moreover, this tree cover product demonstrates the ability of revealing the increasing trend of potential woody cover with mean annual precipitation (MAP) across Texas savanna. Furthermore, the lack of temporal consistency is revealed for this annual product. It is worth noting that the potential woody cover pattern endowed by the precipitation gradient in Texas savanna is in a three-segment shape. [ABSTRACT FROM AUTHOR]

Disturbance by large herbivores, fires, and humans shapes the structure of savannas, altering the amount of woody vegetation and grass. Due to change in the intensity and frequency of these disturbances, savannas are shifting toward grass-dominated or shrub-dominated systems, likely altering animal communities. Small mammals are critical components of savannas, and their distributions likely are affected by these ecosystem-wide changes in vegetative cover. We assessed the responses of small mammals to a gradient of woody cover in low-lying savannas of southeastern Africa. In Kruger National Park (South Africa) and in three nearby reserves (Eswatini), we livetrapped for over 2 years to build multispecies occupancy models that assessed the responses of the small mammal community to grass and woody cover. Overall, whole-community occupancy increased with grass biomass. More species responded positively to woody cover than to grass biomass, but woody cover was associated with reduced occurrence of one species (Mastomys natalensis). Our results suggest that an increase in grass biomass enhances whole-community occupancy of small mammals, but regional diversity is likely to be higher in areas that contain patches of high grass biomass as well as patches of woody cover. [ABSTRACT FROM AUTHOR]

• We altered key successional factors to promote restoration. • Rodeo® outperformed mulching + Oust® in decreasing the cover of Phalaris arundinacea. • Propagule supply limited the establishment of woody but not herbaceous species. • Bare root tree seedlings responded similarly to the two herbicide treatments. • Deer preferred cottonwood and silver maple and avoided swamp white oak. Invasive plants have major impacts on forest ecosystems. Where invasive species alter successional pathways, a site may reach an alternate stable state in which compositional change is unlikely without management intervention. We conducted a restoration experiment designed to alter the successional factors of site availability, species availability, and species performance to disrupt the stable state of invader dominance. In a field dominated by invasive reed canarygrass (Phalaris arundinacea L.), we compared two plot preparation methods (late-season site mulching plus Oust® application, vs. late-season Rodeo® application) to increase site availability and reduce Phalaris performance, and planted native trees and shrubs as seeds and as bare root seedlings at three densities to improve native species availability. We monitored Phalaris growth, other herbaceous species establishment, tree survival, and deer browsing (another influence on species performance) for two growing seasons. Although the mulching plus Oust treatment was initially more successful in terms of its ability to increase site availability (as measured by litter percent cover and depth), this pattern reversed in the second year of the experiment. Throughout the experiment, the Rodeo treatment was superior in terms of its ability to decrease Phalaris performance (as measured by cover and height), and in the second year it also improved the performance of herbaceous plants naturally establishing in the plots (as measured by cover). Volunteer herbaceous plant cover averaged 60% in Rodeo-treated plots by the end of the second growing season. The performance of planted, seeded, and naturally-occurring woody plants was similar across the two herbicide treatments. Overall survival of bare root seedlings was 41%; survival was greater than 70% for both swamp white oak and Dutch elm disease-resistant American elm. Deer preferentially browsed on silver maple seedlings, while demonstrating avoidance of American elm, cottonwood, sandbar willow and swamp white oak. Our results suggest that to promote succession in Phalaris -dominated sites, decreasing Phalaris performance is more important than immediately removing thatch. In terms of species availability, we conclude that propagule limitation was occurring for woody plants but not for herbaceous species; natural tree recruitment was very low, so our alteration of tree species availability was critical in terms of promoting succession to floodplain forest. The restoration approach of stimulating natural succession can be applied to other ecosystems, providing a link between successional theory and management practice. [ABSTRACT FROM AUTHOR]

The area of indigenous vegetation and habitat remaining on New Zealand's primary agricultural lands continues to decrease, but it has been difficult to obtain reliable estimates of the extent and causes of loss. We assess change and identify predictors of vegetation clearance in 856 recommended areas for protection (RAPs) from 35 ecological districts in the North and South Islands, New Zealand, for the period 1989 to 2015. Over 27 years, 7152 ha of these RAPs were cleared (2.3% by area), with rates varying over space and time. Native forest was least commonly cleared (422 ha removed), followed by native non-woody vegetation (1294 ha), native shrubland (1378 ha), and 'other' vegetation (4058 ha). The probability of clearance peaked during 2001 to 2008 at 0.14% yr-1, but it was still nearly double the 1989-2001 levels (0.06% yr-1) from 2008 to 2015 (0.11% yr-1). The annualised clearance probabilities after 2001 were comparable to the rates of deforestation in the pre-1840 period of human settlement and about a third of that recorded from 1840 to 1970, the most intensive known period of anthropogenic clearance in New Zealand. Clearance rates were higher around the edges of small RAPs without legal protection and in drier, cooler areas, generally and increasingly over time. Amount of surrounding cropping/horticulture was negatively associated with clearance, as initially was dairy before developing a slightly positive association. Forestry was positively associated with clearance up until 2008. Our results show proportionally greater clearance of marginal agricultural land with high biodiversity values as time goes on, probably facilitated by the increasing use of technology, such as irrigation and fertilisation, to circumvent environmental limitations to plant growth. These results demonstrate ongoing attrition of the highest-value native habitat remaining on private land, and the inadequacy of the current protection framework to safeguard it. [ABSTRACT FROM AUTHOR]

Land managers frequently apply vegetation removal and seeding treatments to restore ecosystem function following woody plant encroachment, invasive species spread, and wildfire. However, the long‐term outcome of these treatments is unclear due to a lack of widespread monitoring. We quantified how vegetation removal (via wildfire or management) with or without seeding and environmental conditions related to plant community composition change over time in 491 sites across the intermountain western United States. Most community metrics took over 10 years to reach baseline conditions posttreatment, with the slowest recovery observed for native perennial cover. Total cover was initially higher in sites with seeding after vegetation removal than sites with vegetation removal alone, but increased faster in sites with vegetation removal only. Seeding after vegetation removal was associated with rapidly increasing non‐native perennial cover and decreasing non‐native annual cover. Native perennial cover increased in vegetation removal sites irrespective of seeding and was suppressed by increasing non‐native perennial cover. Seeding was associated with higher non‐native richness across the monitoring period as well as initially higher, then declining, total and native species richness. Several cover and richness recovery metrics were positively associated with mean annual precipitation and negatively associated with mean annual temperature, whereas relationships with weather extremes depended on the lag time and season. Our results suggest that key plant groups, such as native perennials and non‐native annuals, respond to restoration treatments at divergent timescales and with different sensitivities to climate and weather variation. [ABSTRACT FROM AUTHOR]

Background and aims: In the semi-arid saline Chaco, Argentina, the nanophanerophytes presence and the succulent leaf type are frequent. To determine if the occurrence of both traits is related to soil salinity, this paper describes the distribution of life forms and leaf types in relation to soil salinity between two woody plant communities. M&M: Sampling of woody plant and soil was carried out in both a scrubland and a xerophilous forest on 25 subplots of 100 m2 at each site. Soil electrical conductivity and pH were determined down to a depth of 50 cm. Stratification and plant cover, abundance, species richness and diversity index were described. The degree of similarity between sites was evaluated according to the number of nanophanerophyte and succulent-leaves shared species, using the Sørensen coefficient. The species were grouped considering simultaneously their life form and leaf type. Relationships between salinity and plant groups were evaluated by means of redundancy analysis. Results: Richness, diversity and structural complexity were greater in the forest. The similarity between sites was low. Succulent-leafed nanophanerophytes were dominant in the scrubland, with high salinity and pH. In the forest, sclerophyllous- leafed microphanerophytes were dominant, with low salinity and pH. Conclusion: The distribution of succulent-leaves nanophanerophytes presented differences according to the salinity of the soil of both woody communities. [ABSTRACT FROM AUTHOR]

Certain plant genotypes can achieve optimal growth under appropriate environmental conditions. Under high planting density conditions, plants undergo competition for uptake and utilization of light and nutrients. However, the relationship between whole-genome expression patterns and the planting density in perennial woody plants remains unknown. In this study, whole-genome RNA sequencing of poplar (Populus × euramericana) was carried out at three different sampling heights to determine gene expression patterns under high (HD) and low (LD) planting densities. As a result, 4,004 differentially expressed genes (DEGs) were detected between HD and LD, of which 2,300, 701, and 1,003 were detected at the three positions, upper, middle and bottom, respectively. Function annotation results further revealed that a large number of the DEGs were involved in distinct biological functions. There were significant changes in the expression of metabolism-related and stimulus-related genes in response to planting density. There were 37 DEGs that were found at all three positions and were subsequently screened. Several DEGs related to plant light responses and photosynthesis were observed at different positions. Meanwhile, numbers of genes related to auxin/indole-3-acetic acid, and carbon and nitrogen metabolism were also revealed, displaying overall trends of upregulation under HD. These findings provide a basis for identifying candidate genes related to planting density and could increase our molecular understanding of the effect of planting density on gene expression. [ABSTRACT FROM AUTHOR]

African elephants (Loxodonta africana) negatively influence woody vegetation, causing structural changes to ecosystems. Field-based survey methods used to monitor elephant impact, while valuable, are costly and time-consuming to execute. By applying distance-sampling techniques such as remote sensing technology, inaccessible areas can be surveyed. This overview provides insight into methods used by scientists to determine the impact of elephants on woody vegetation in sub-Saharan Africa. Data were sourced from a variety of research databases. Findings indicate that 87% (n = 92) of the reviewed studies used field-based methods and 13% (n = 14) used remote sensing-based methods. We explore the national affiliations of the lead and the last authors of the reviewed studies and the scientific journals that published them. Field-based is the dominant method used in the majority of published studies on elephant impact. The majority of these studies were published in European and American journals, instead of African journals, which are less represented. However, the majority of the lead and last authors’ affiliations for both field-based and remote sensing based methods are affiliated with African institutions. We conclude that there is a need to improve the integration of remote sensing techniques into conservation and other ecological fields. [ABSTRACT FROM AUTHOR]

Summary: Despite the importance of nonstructural carbohydrates (NSC) for growth and survival in woody plants, we know little about whole‐tree NSC storage. The conventional theory suggests that NSC reserves will increase over the growing season and decrease over the dormant season. Here, we compare storage in five temperate tree species to determine the size and seasonal fluctuation of whole‐tree total NSC pools as well as the contribution of individual organs.NSC concentrations in the branches, stemwood, and roots of 24 trees were measured across 12 months. We then scaled up concentrations to the whole‐tree and ecosystem levels using allometric equations and forest stand inventory data.While whole‐tree total NSC pools followed the conventional theory, sugar pools peaked in the dormant season and starch pools in the growing season. Seasonal depletion of total NSCs was minimal at the whole‐tree level, but substantial at the organ level, particularly in branches. Surprisingly, roots were not the major storage organ as branches stored comparable amounts of starch throughout the year, and root reserves were not used to support springtime growth.Scaling up NSC concentrations to the ecosystem level, we find that commonly used, process‐based ecosystem and land surface models all overpredict NSC storage. [ABSTRACT FROM AUTHOR]

Aims Exploring species-genetic diversity correlation (SGDC) is essential for understanding spatial patterns of diversity and the underlying mechanisms. Until now, latitudinal patterns of species diversity (SD) and genetic diversity (GD) were rarely studied simultaneously. As the freezing-tolerance hypothesis predicts a decrease of SD from low to high latitudes and the central-marginal hypothesis predicts a unimodal pattern of GD along latitude, we hypothesized that SD and GD are uncorrelated. We also tested how climatic and edaphic factors affect the correlation between the two levels of biodiversity. Methods We measured (i) SD (species richness and Simpson's diversity index) and community dissimilarity of woody plants (63 plots), (ii) GD (allelic richness and expected heterozygosity) and genetic differentiation of a dominant tree species (Euptelea pleiospermum ; 678 individuals from 21 populations) using nuclear microsatellite data, and (iii) climatic (annual mean precipitation, annual mean temperature, minimum temperature, maximum temperature, annual relative moisture, solar radiation, photosynthetically active radiation) and edaphic (total C, total N, total P, available P, K, Ca, Mg, Al, Fe, Mn, Ni, Zn, B, Mo, Cu, pH) variables of 21 sites. We conducted both linear and quadratic regression analyses of diversity parameters against latitude. Relationships between SD and GD were tested using Pearson's correlation. Pearson's and Spearman's ρ correlation coefficients were calculated between diversity parameters and environmental variables. We used stepwise multiple regression analysis to identify the significant environmental predictors of SD and GD. Important Findings We observed no significant correlation between measures of SD and GD. SD decreases with increasing latitude, which can be partly explained by the freezing-tolerance hypothesis, whereas GD presents a unimodal pattern along the latitudinal gradient, which is consistent with the prediction of the central-marginal hypothesis. The contrasting latitudinal patterns of SD and GD indicate that the two levels of biodiversity do not co-vary in space. Based on both correlation analysis and stepwise multiple regression analysis, SD is only related to climatic variables, whereas GD is mainly related to edaphic variables. Our results show that different geographical and environmental factors affect SD and GD, driving the non-significant correlation between the two fundamental levels of biodiversity. Furthermore, a significantly positive correlation was observed between genetic distance and community dissimilarity, both of which were significantly correlated with geographical distance. [ABSTRACT FROM AUTHOR]

The Biggest Bang for the Buck: Cost-Effective Vegetation Treatment Outcomes Across Drylands of the Western USA Restoration and rehabilitation treatments that manipulate vegetation can be expensive to implement but are infrequently evaluated to determine whether spending more improves intended outcomes. We assessed commonly implemented vegetation treatments and costs relative to their outcomes across sagebrush shrublands and pinyon-juniper woodlands in the western United States. [Extracted from the article]

Most studies suggest that multiple factors are responsible for woody plant encroachment, but are inconclusive on its causes. Woody plant encroachment is modified by local patterns of disturbance, topography, soil texture and fertility, and their relative importance and interaction strength varies among locations. We used grassland communities, Carletonville Dolomite Grassland (CDG), Rand Highveld Grassland (RHG) and abiotic factors (Soil Organic Carbon (SOC), Total nitrogen (TN), Phosphorus (P), Potassium (K), Sodium (Na), Calcium (Ca), Magnesium (Mg) and pH) to investigate habitat preferences of Seriphium plumosum L. in South African semi-arid grassland. Grassland community had a significant effect on S. plumosum density, canopy size, and on components of soil fertility (P< 0.05). Slope position had a significant effect on S. plumosum density and canopy size (P< 0.05). Seriphium plumosum density was significantly lower (23 plants/50 m2±2.39 (SE)) in CDG than in RHG (40 plants/50 m2±4.19). By contrast, S. plumosum canopy size was significantly higher (1.39 m2±0.11) at CDG than at the RHG (1.06 m2±0.08). The interaction of grassland community and slope position had a significant effect on S. plumosum density and soil sodium content (P< 0.05). Bottom slope regions in RHG (59.00 plants/50 m2±8.62) had higher S. plumosum density than bottom slope regions (19.75 plants/50 m2±3.01) in CDG. Soil sodium content was similar in CDG slopes and higher than in RHG slopes. Seriphium plumosum density was positively related to components of soil fertility; P (r2 = 0.1270; P 0.0036), K (r2 = 0.0786; P 0.0237), Na (r2 = 0.0686; P 0.0350), Ca (r2 = 0.0681; P 0.0358), and SOC content (r2 = 0.0669; P 0.0374). However, Seriphium plumosum canopy size did not show any relationship with components of soil fertility. This study revealed that S. plumosum density in grassland communities increased with increasing soil texture and fertility. [ABSTRACT FROM AUTHOR]

Understanding what determines species’ geographic distributions is crucial for assessing global change threats to biodiversity. Measuring limits on distributions is usually, and necessarily, done with data at large geographic extents and coarse spatial resolution. However, survival of individuals is determined by processes that happen at small spatial scales. The relative abundance of coexisting species (i.e. ‘community structure’) reflects assembly processes occurring at small scales, and are often available for relatively extensive areas, so could be useful for explaining species distributions. We demonstrate that Bayesian Network Inference (BNI) can overcome several challenges to including community structure into studies of species distributions, despite having been little used to date. We hypothesized that the relative abundance of coexisting species can improve predictions of species distributions. In 1570 assemblages of 68 Mediterranean woody plant species we used BNI to incorporate community structure into Species Distribution Models (SDMs), alongside environmental information. Information on species associations improved SDM predictions of community structure and species distributions moderately, though for some habitat specialists the deviance explained increased by up to 15%. We demonstrate that most species associations (95%) were positive and occurred between species with ecologically similar traits. This suggests that SDM improvement could be because species co-occurrences are a proxy for local ecological processes. Our study shows that Bayesian Networks, when interpreted carefully, can be used to include local conditions into measurements of species’ large-scale distributions, and this information can improve the predictions of species distributions. [ABSTRACT FROM AUTHOR]

Recent studies have concluded that native and invasive species share a common set of trait relationships. However, native species in isolated regions might be functionally constrained by their unique evolutionary histories such that they follow different carbon capture strategies than introduced species. We compared leaf traits relating to resource investment, carbon return, and resource-use efficiency in 16 native (endemic) and three non-native (invasive) species in a temperate forest in Canterbury, South Island, New Zealand. Trait differences were more closely associated with leaf habit than nativity. Deciduous species (including invaders) exhibited greater maximum photosynthetic rates at similar resource costs, which resulted in greater nitrogen- and energy-use efficiencies than evergreen natives. Leaf area was the only trait that differed significantly by nativity (over two-fold larger in invaders). Invaders and deciduous natives both occupied the ‘fast return’ end of the leaf economics spectrum in contrast to the native evergreens which had comparatively slow return on investment. Dominant woody invaders in this forest are physiologically distinct from many New Zealand endemic species, which are overwhelmingly evergreen. It remains unclear whether these trait differences translate to an ecological divergence in plant strategy, but these results suggest that ecophysiological tradeoffs are likely constrained by biogeography. [ABSTRACT FROM AUTHOR]

Abstract: Question: What are the composition and spatial patterns of native woody plant communities in the southern Great Chaco and Espinal? Location: Córdoba Province, central Argentina, an area of ca. 161,000 km2. Methods: We collected 351 geo‐referenced relevés representative of the geographic, topographic and ecological variation of the Chaco and Espinal woody vegetation in central Argentina. The relevés were classified into vegetation types using the hierarchical ISOPAM method. Forest and shrubland types were described on the basis of diagnostic species occurrences and their distribution in relation to environmental factors. A map of the actual vegetation derived from remote‐sensed images (Landsat) and field data was used to describe the current distribution and abundance of the different vegetation types. Results: The classification of the 351 plots × 837 species matrix revealed two major clusters comprising seven woody vegetation types corresponding to Chaco lowland and mountain forests and shrublands, Espinal forests and edaphic vegetation. The most important gradients in woody vegetation types are related to elevation, temperature and rainfall variables. Conclusions: Subtropical seasonally dry woody plant communities from the southern extreme of the Great Chaco and Espinal forests were described for the first time based on complete floristic data. Our results show that lowland Chaco native forests, as well as replacement communities, are still present in its southern distribution range and are well distinguishable from other vegetation types such as the Espinal and mountain forests. Overall, extensive Espinal forests have almost disappeared while Chaco vegetation is highly fragmented and degraded. [ABSTRACT FROM AUTHOR]

Global changes, such as increased temperatures and elevated CO2, are driving shifts in plant species distribution and dominance, like woody plant encroachment into grasslands. Local factors within these ecotones can influence the rate of regime shifts. Woody encroachment is occurring worldwide, though there has been limited research within coastal systems, where mangrove (woody shrub/tree) stands are expanding into salt marsh areas. Because coastal systems are exposed to various degrees of nutrient input, we investigated how nutrient enrichment may locally impact mangrove stand expansion and salt marsh displacement over time. We fertilized naturally co-occurring Avicennia germinans (black mangrove) and Spartina alterniflora (smooth cordgrass) stands in Port Aransas, TX, an area experiencing mangrove encroachment within the Northern Gulf of Mexico mangrove-marsh ecotone. After four growing seasons (2010–2013) of continuous fertilization, Avicennia was more positively influenced by nutrient enrichment than Spartina. Most notably, fertilized plots had a higher density of taller (> 0.5 m) mangroves and mangrove maximum height was 46% taller than in control plots. Fertilization may promote an increase in mangrove stand expansion within the mangrove-marsh ecotone by shifting Avicennia height distribution. Avicennia individuals, which reach certain species-specific height thresholds, have reduced negative neighbor effects and have higher resilience to freezing temperatures, which may increase mangrove competitive advantage over marsh grass. Therefore, we propose that nutrient enrichment, which augments mangrove height, could act locally as a positive feedback to mangrove encroachment, by reducing mangrove growth suppression factors, thereby accelerating the rates of increased mangrove coverage and subsequent marsh displacement. Areas within the mangrove-marsh ecotone with high anthropogenic nutrient input may be at increased risk of a regime shift from grass to woody dominated ecosystems. [ABSTRACT FROM AUTHOR]