Native Deciduous Tree Research Articles

Effects of Leaf Species and Conditioning State of Fresh Leaves on Colonization by Stream and Pond Macroinvertebrates

Fresh, green leaves are increasing as resources in aquatic ecosystems due to more frequent severe spring and summer storms, but research on allochthonous resources typically uses senescent leaves. We examined macroinvertebrate colonization of green leaves of three native deciduous trees (red maple, red oak, and tulip poplar) over two weeks within both a stream and fishless pond. Leaf colonization varied depending on the taxa of leaves and colonizers, submersion time, and the ecosystem examined. Within the stream, the densities of isopods (Lirceus sp.) and snails (mostly the invasive Potamopyrgus antipodarum) did not vary significantly across leaf species. In contrast, mayflies (Tricorythodes sp.) in the stream colonized tulip poplar in greater numbers than red oak leaves, while higher densities of planarians (order Tricladida) occurred within red oak leaves. The numbers of mayflies and snails decreased significantly by the second week, but the densities of isopods and planaria within stream leaf packs were consistent. In contrast, within the pond, significantly more isopods (Caecidotea communis) were collected after the first than after the second week of submersion and in tulip poplar leaves. Clams (Sphaeriidae) in the pond, on the other hand, were more prevalent in the second week but did not discriminate among leaf species. While the number of leeches (mostly Helobdella stagnalis) was consistent across weeks, significantly fewer leeches resided within tulip poplar leaves than within red oak leaves. Our results suggest that there are no consistent colonization-preference rankings of species of fresh leaves across freshwater benthic macroinvertebrate taxa. Even within a functional feeding group (e.g., the two types of isopods and snails, all detritivore-herbivores), there were differences in colonization patterns. Therefore, increased allochthonous inputs of fresh leaf litter due to severe spring- and summer-time storms are likely to promote the populations of various taxa to different extents.

Bilateral cooperation - Fostering the ability of native European beech and sessile oak forests in the border region against the impacts of climate change

Adequate adaptions and actions to combat anthropogenic climate change (CC) are significant challenges of the 21st century. In Europe, according to the European Environmental Agency, warming of around 2°C is expected under the moderate climate scenario (RCP 4.5) by the end of the century, but the pessimistic RCP 8.5 scenario project an increase of up to 6°C. In addition to the rise in temperature, changes in precipitation and increased frequency of extreme weather events are predicted. New environmental conditions affect tree species and habitats differently; thus, forest biodiversity and local tree species compositions probably will be altered in many regions in the future. The effects may be manifold: some tree species may persist, locally adapt and migrate, while others may disappear from given regions and be replaced by native or non-native species. The native forests of the Austrian-Hungarian border region are particularly affected by the climate change. To mitigate the consequences of anthropogenic climate change to preserve forest biodiversity for future generations and to enable their use, deliberate and planned human interventions and actions are essential. These require transnational or even global efforts since nature and climate do not recognise man-made borders. The REIN-Forest project (Interreg V-A Austria-Hungary Programme - ATHU150), a bilateral project between Austria and Hungary, aimed to establish harmonised protection measures for the conservation of native forests in Northern, Central and Southern Burgenland, Vienna, Vienna Umland-South, Lower Austria South, Graz and Eastern Styria, Győr-Moson-Sopron, Vas and Zala counties (the so-called programme area). In the scope of this project, international cooperation between three project partners: the Austrian Research Centre for Forests (BFW, Austria), the Forest Research Institute – University of Sopron (SOE ERTI, Hungary) and the Vas County Government Office (VVÖH, Hungary) was established. Previous results and outputs of the SUSTREE project (Interreg Central Europe CE614), such as: a) Transnational delineation model of conservation and forest seed transfer zones in climate change, b) Report of intraspecific response function and derivation of climate transfer limits, SusSelect data, recommendations and c) Application of the species distribution models for the delineation of seed transfer zones/models in Central Europe, were put into practice during the project, focusing on two native deciduous forest tree species of the Austrian-Hungarian border region: European beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Liebl.). During the REIN-Forest project, the following joint documents were prepared and several activities were implemented: 1. Model-based document on the current state and future perspectives of European beech and sessile oak forests; 2. Bilateral strategy for the transfer of forest reproductive material (FRM) and its use in the Austrian-Hungarian border region; 3. Establishment of altogether six demonstration sites (three in each country) with local and climate-adapted FRM of European beech and sessile oak for long-term monitoring; 4. Management and monitoring plan of the demonstration sites; 5. Joint bilingual communication strategy, which included informative programmes and meetings with professionals, locals and schools and also education material for further use. REIN-Forest focused on using scientific results and outputs in the field of applied forestry and awareness-raising. Besides strategies, recommendations and reports that would facilitate forest managers' decisions for the future in the border region, events and workshops were offered for forestry practitioners, school pupils and the public and a short film and educational materials were published.

Comparative Study of the Phenology of Seven Native Deciduous Tree Species in Two Different Mesoclimatic Areas in the Carpathian Basin

The impact of global warming on plant phenology is the subject of a growing number of studies. However, most of these do not focus on woody species, and few examine the entire annual phenological cycle of woody species. In this paper, we explore the phenological pattern of seven woody species native to Europe under ex situ conditions for 3 years, in two urban areas with different mesoclimates. The average temperature differs by 1.81 °C between the two sites. The investigated plants were clonally identical for each species, and the exact same care protocol was kept at both sites. Despite the large variation in the phenological pattern between years, during the study, spring phenophases occurred earlier, while the examined autumn phenophases were delayed at the site observing a higher average temperature. The phenological sensitivity of flowering was significantly higher than that of leaf bud burst. The growing season was 14.8 days longer at the site with a higher average temperature. In most cases, a significant correlation was obtained between the examined phenophases and climatic factors at both sites. Among the autumn phenophases, the strongest correlation was found between the maximum temperature between July and October and the beginning of leaf coloring.

The Archaeology of Ancient Japanese Gardens

abstract: This article summarizes the results of archaeological research on some 20 Japanese garden sites dating from the fourth to twelfth centuries a.d., emphasizing the site plan, remains of structures, stone groupings, and ponds. Associated plant remains from five sites are tabulated and briefly discussed. I introduce some early Chinese and Korean antecedents and provide historical context. Gardens with rectangular ponds were introduced from the continent in the Asuka Period (a.d. 538–710). From the Nara Period (a.d. 710–794), garden making was naturalized in a Japanese asymetrical curving style in which structures were located away from the central axis. The gardens discussed here represent a small sample of the original gardens. They include two early examples of an adopted continental style (i.e., Uenomiya and Furumiya), a garden from an imperial palace site, gardens enclosing Heian Period shinden type architecture (raised residence with side wings) and its adapted Pure Land form, and a garden associated with the palace of a retired emperor. Plantings show a combination of flowering trees and shrubs, many introduced from the continent, combined with native deciduous and evergreen trees. Continental examples of gardens with rectangular ponds belong to royal palaces and were symbols of royal authority, as were the examples dated to the Asuka Period. In the Heian Period, state gardens such as Shinsen'en were used for state functions and required ample space and simple organization, while gardens sponsored by elite courtiers such as the Fujiwara show the expression of Buddhist belief. In the Toba Rikyū, built by retired emperors under a complex insei (retirement) system, imperial mausolea shared the landscape with mansions, Buddhist temples, and chapels. Groupings of stones, curving streams, dry landscapes, and low waterfalls probably all occurred as early as the Nara Period.

Tree sapling vitality and recovery following the unprecedented 2018 drought in central Europe

BackgroundOngoing climate change is anticipated to increase the frequency and intensity of drought events, thereby affecting forest recovery dynamics and elevating tree mortality. The drought of 2018, with its exceptional intensity and duration, had a significant adverse impact on tree species throughout Central Europe. However, our understanding of the resistance to and recovery of young trees from drought stress remains limited. Here, we examined the recovery patterns of native deciduous tree sapling species following the 2018 drought, and explored the impact of soil depth, understory vegetation, and litter cover on this recovery. MethodsA total of 1,149 saplings of seven deciduous tree species were monitored in the understory of old-growth forests in Northern Bavaria, Central Germany. The vitality of the saplings was recorded from 2018 to 2021 on 170 plots. ResultsFagus sylvatica was the most drought-resistant species, followed by Betula pendula, Acer pseudoplatanus, Quercus spp., Corylus avellana, Carpinus betulus, and Sorbus aucuparia. Although the drought conditions persisted one year later, all species recovered significantly from the 2018 drought, albeit with a slight decrease in vitality by 2021. In 2018, the drought exhibited a more pronounced adverse effect on saplings in deciduous forests compared to mixed and coniferous forests. Conversely, sapling recovery in coniferous and mixed forests exceeded that observed in deciduous forests in 2019. The pivotal factors influencing sapling resilience to drought were forest types, soil depth, and understory vegetation, whereas litter and forest canopy cover had a negative impact. ConclusionLong-term responses of tree species to drought can be best discerned through continuous health monitoring. These findings demonstrate the natural regeneration potential of deciduous species in the context of climate change. Selective tree species planting, soil management practices, and promoting understory diversity should be considered when implementing adaptive management strategies to enhance forest resilience to drought events.

Spatial association of bamboos with trees in a commercial tree plantation forest in Myanmar

Abstract Bamboos are mainly distributed in subtropical to tropical areas. Bamboos provide numerous ecosystem services, while the expansion of bamboo gives negative impacts on forest ecosystems. Despite big impacts of bamboos on a forest ecosystem, ecological characteristics of bamboo remain poorly understood. The spatial distributional patterns of three bamboo species, Cephalostachyum pergracile, Bambusa polymorpha, and Dinochloa maclellandii, were studied in a commercial tree plantation of native deciduous tree species in the Bago Mountains, Myanmar. A point process analysis revealed a clumped distribution for each bamboo species. The distributional overlapping of the species was analysed for every pair of two species. The distribution of C. pergracile was little overlapped with those of D. maclellandii and B. polymorpha. Cephalostachyum pergracile was significantly more abundant on gently sloping ridges, whereas D. maclellandii was more abundant on a steeply sloping site. Bambusa polymorpha did not show these patterns with topography. The exclusive distribution of C. pergracile and D. maclellandii may be, at least partly, explained by the opposite topographic preferences of the species. Cephalostachyum pergracile tended to be found far from large trees that cast shade, although B. polymorpha tended to be found with large trees, suggesting that B. polymorpha may be more shade tolerant than C. pergracile. The difference in shade tolerance may contribute to the exclusive distribution of the species. The habitat preference information obtained in this study will contribute to sound bamboo management practices in Myanmar and enable bamboo population sizes to be increased through creation of favourable habitats in forests.

Differential effects of acid rain on photosynthetic performance and pigment composition of the critically endangered Acer amplum subsp. catalpifolium

Acer amplum subsp. catalpifolium is a critically endangered, native deciduous broad-leaved tree species mainly distributed in the rainy zone of west China. Acid rain is a frequent phenomenon in this region and its impact on regional forests, especially for susceptible species have major implications on community stability and biodiversity conservation. To understand the basic physiological responses of A. amplum subsp. catalpifolium to acid rain, a simulation experiment spanning 18 months was conducted. The aim is to determine the effects of acidity levels (pH 2.5, 3.5, and 4.5), chemical composition (H2SO4: HNO3 ratio of 7.5:1 and 5:4.1, respectively), and deposition patterns (soil addition and leaf spraying modes) on photosynthetic performance and stress status of A. amplum subsp. catalpifolium The results showed that simulated acid rain can enhance the peak photosynthetic rate (Pn) and stomatal conductance (Cs) in the diurnal variation of A. amplum subsp. catalpifolium under soil addition mode, and it is attributed to the increased net photosynthetic rate at the light saturation point (Amax), net photosynthetic rate at saturating CO2 concentration (Pmax) and various chlorophyll fluorescence parameters (ΦPSII, Fv/Fm, Fv/F0, and qP). On the contrary, the photosynthetic performance of A. amplum subsp. catalpifolium was significantly inhibited by acid rain under leaf spraying mode, with increased dark respiration rate (Rd) and photorespiration rate (Rp). The reduction levels in Amax and Pmax was higher in the nitric based acid rain compared to sulfuric acid dominant acid rain. In general, improved nutrient availability brought about by acid rain on soil promoted the photosynthetic performance of A. amplum subsp. catalpifolium. Meanwhile, acid rain in direct contact with the leaves negatively affects leaf performance and chemical makeup. Therefore, acid rain patterns (such as fog or snow) in direct contact with leaves should be accounted for in the protection of A. amplum subsp. catalpifolium.

Two centuries of forest succession, and 30 years of vegetation changes in permanent plots in an inland sand dune area, The Netherlands.

There are not many sites in densely populated temperate Europe where primary forest succession has a chance to run without direct human intervention for a long time and over a relatively large area. The extensive drift sand area of the Veluwe, central Netherlands, provided an opportunity to study succession in a formerly open and dynamic inland sand dune system combining chronosequence and permanent plot approaches. Different successional stages, aged up to 205 years since the first tree individuals established, were identified and vegetation studied using 1200 permanent plots established in 1988 in three adjacent sand dune complexes of different successional age, and resampled during the past three decades. After two centuries, forest succession has proceeded to a pine forest with gradually increasing participation of native deciduous trees. However, their expansion has been arrested by browsing of wild ungulates. Species diversity peaked after about 40 years of forest succession, then declined, and increased again after 100 years. During the past three decades, the herb layer has differentiated in the oldest plots, and the spontaneous forest succession is still in progress. Besides open drift sand with early successional stages, also the spontaneously established late successional forests are valuable from the conservation point of view.

Потенціал вирощування робінії звичайної (Robinia pseudoacacia L.) на порушених землях Східної Німеччини

Проаналізовано результати модельних проектів із розведення швидкозростаючих порід дерев для виробництва відновлюваної сировини в короткому циклі у лісових насадженнях та на рекультивованих після добування бурого вугілля землях Східної Німеччини. Особливу увагу звернено на робінію звичайну, оскільки її рекомендують вирощувати на малопродуктивних і порушених землях, а не за рахунок площі корінних листяних насаджень. На дев'яти дослідних територіях Бранденбурга (Східна Німеччина) проводять випробування нових концепцій культивування робінії звичайної для енергетичного використання деревини. Розробляють шляхи мобілізації раніше невикористаних, але стабільно доступних запасів деревини робінії відповідно до "Національного плану дій щодо біомаси для Німеччини" (2009). Перевагу надають економічно обґрунтованому поводженню з наявними лісовими культурами робінії на малопродуктивних і рекультивованих землях. Встановлено придатність робінії звичайної для вирощування з метою енергетичного використання на малопродуктивних землях із невеликою кількістю опадів. Оцінено потенціал біомаси робінії звичайної у Бранденбурзі, який можна мобілізувати вирощуванням робінії в короткому плантаційному циклі. Інтенсивність росту робінії звичайної була високою вже в перший рік вирощування. Дослідження підтверджують важливість властивостей ґрунту, зокрема води, доступної рослинам, аерації ґрунту та глибини кореневмісного шару для продуктивного росту й розвитку саджанців робінії звичайної. Висока інтенсивність коренепаросткового відтворення робінії є сприятливою для її вирощування з енергетичною метою. Застосування відповідної технології лісозаготівлі для невеликих площ та невеликий річний приріст за діаметром основи робінієвого пагона (на висоті зрізання приблизно 5 см) ускладнюють технологічний процес. Для його оптимізації потрібні короткі транспортні маршрути до споживача та можливості сушіння деревини. Висока щільність деревини робінії зумовлює високу теплоту згоряння її тріски. Робінія звичайна на малопродуктивних землях в умовах низької кількості опадів має високий приріст біомаси у перші п'ять років.

Effects of Seasonality, Tree Species and Urban Green Space on Deciduous Leaf Litter Decomposition in Lithuania

Understanding ecological processes and environmental change in different urban green spaces is an important challenge to secure human well-being. The variety of urban green spaces provides a platform to generate knowledge on how urban environments affect tree leaf decomposition and quality. We measured the leaf litter decomposition of four dominant native deciduous tree species from five different urban green spaces over three time periods in Kaunas, Lithuania. Using the modified litter bag technique, we calculated the decomposition of 60 leaf litter samples for 4, 8, and 12 months respectively. For each leaf litter sample, we determined total N, total P, and organic C. Results indicated that the decomposition of leaf litter amongst tree species, urban green spaces and seasonality (time) were significantly different. The leaf litter of Betula pendula and Acer platanoides from street green spaces decomposed fastest during the spring-summer period. Quercus robur showed small but significant leaf litter loss differences between the green spaces, with the leaf litter from peri-urban forest decomposing the fastest. A decreased C:N ratio for Q. robur leaf litter showed accelerated leaf litter decay. In conclusion, our results show that the ecological processes of leaf litter decomposition, differs between tree species, type of urban green spaces and seasonality and thus must be considered in urban town planning to help maintain urban environments.

Impact of urban green spaces, native tree species and seasons on soil pH in Kaunas, Lithuania

Tree growth is sensitive to soil pH in urban areas and is often higher than in rural forest. However, there are knowledge gaps on how soil pH and alkalization are affected by urban environments and seasonal climate as well as the cascading effects on tree species. In order to fulfill these gaps, we analyzed the soil pHCaCl of four common native deciduous tree species: Acer platanoides, Tilia cordata, Quercus robur and Betula pendula in five different types of urban green spaces in Kaunas city municipality (Lithuania). The results show that soil pH in urban environments with Betula pendula sites were most alkaline (pH 7.04), whereas the soil pH of urban environments with Acer platanoides (pH 6.7) and Tilia cordata (pH 6.8) were most acidic. The soil pH of street tree greeneries was alkaline, while soils of peri-urban forests and large urban parks were acidic. Differently to natural conditions in peri urban forests the soil pH level drop down by 0.5 is observed during spring-autumn period in broad street greeneries with largest urban pressure. The variation in soil pH of the different types of green space and tree species shows that city planner should consider the unique conditions of all green space to maximize their potential for human well-being.

Impact of an invasive tree on arthropod assemblages in woodlots isolated within an intensive agricultural landscape

AbstractAimLandscape simplification and the spread of invasive species are considered beyond the main threats to global biodiversity. It is well recognized that non‐crop habitats bring complexity to farmland and provide refuge for a wide range of organisms, including arthropods. However, knowledge about the effects of invasive trees on arthropods in non‐crop habitats in intensive agricultural landscapes is still weak. Therefore, we examined differences in the arthropod assemblages between woodlots formed by the invasive black locust (Robinia pseudoacaciaL.) and by native deciduous tree species in the intensive agricultural landscape.LocationCzech Republic, Central Europe.MethodsWe used a multi‐taxonomic approach to record arthropod assemblages using various sampling methods. The impacts of woodlot habitat structure were investigated across 13 arthropod taxa from different trophic levels.ResultsTotal abundance and species richness of all arthropods and the majority of the herbivore taxa were lower inR. pseudoacaciawoodlots, likely due to losses of the forest canopy specialists. The forest specialists were associated with the native woodlots with more developed canopy and shrub layers. The impoverished diversity of the forest specialists and canopy herbivores in theR. pseudoacaciawoodlots was partly compensated by the higher presence of species exploiting a well developed herb layer and open‐habitat specialists, including threatened species.Main conclusionsNative woodlots and those formed byR. pseudoacaciadiffer in vegetation structure and host different assemblages of arthropods. Therefore, parallel presence of both types of woodlots supports arthropod diversity in otherwise simplified agricultural landscapes through creating more complex mosaic of habitats.

Response of carabid and arachnid assemblages on plant invasion in woodlots within an agricultural landscape

Landscape simplification and the spread of invasive species are considered the main threats to global biodiversity. It is well recognized that non-crop habitats bring complexity to farmland and provide refuge for arthropods. However, knowledge about the effects of invasive trees on arthropods in non-crop habitats in intensive agricultural landscapes is still weak. Therefore, we examined differences in the carabid and arachnid assemblages between woodlots formed by the invasive black locust (Robinia pseudoacacia L.) and by native deciduous tree species in the intensive agricultural landscape in the Czech Republic, Central Europe. We sampled carabids, harvestmen and spiders by using pitfall traps, sweeping the vegetation and light trapping. Effects of woodlot’s habitat structure, land cover composition in the surroundings and the area of woodlots were included to the analyses. The abundance of carabids was lower in R. pseudoacacia woodlots. Carabid individuals could benefit from the more favourable microclimate in the native woodlots, in which relatively greater humidity may support more ample food resources. On the contrary, species richness of carabids did not differ between the woodlot types. The abundance and species richness of arachnids did not differ between the woodlot types. Number of individuals increased with increasing woodlot’s area and the species richness increased with the more open woodlot’s habitat structure. The forest specialists of both groups were associated with the native woodlots with more developed canopy and shrub layers. The diversity losses of the arachnid forest specialists in the R. pseudoacacia woodlots were replaced by the species exploiting well-developed herb layer, and open-habitat specialists, including threatened species. Conversely, carabids of open habitats had no affinity to woodlot types. Native woodlots and those formed by R. pseudoacacia differed in vegetation structure and hosted different arachnid and carabid assemblages. Therefore, parallel presence of both types of woodlots supports arthropod diversity in otherwise simplified agricultural landscapes through creating more complex mosaic of habitats.

Global warming likely to enhance black locust (Robinia pseudoacacia L.) growth in a Mediterranean riparian forest

Mediterranean riparian forests are comparably humid environments that provide shelter for several broadleaved deciduous tree species at their southernmost distribution margin. The stability of these communities, however, is threatened by climate change as well as invasive tree species, such as black locust (Robinia pseudoacacia L.). So far, black locust's European distribution appears to be mostly limited by low temperatures, but global warming might enhance its growth in colder areas. Moreover, R. pseudoacacia can better access water from the phreatic level than some native non-phreatophytic tree species such as European ash (Fraxinus excelsior L.). In this study, we compare the performance of European ash, a native deciduous tree species at its southernmost distribution border, with the invasive black locust, under a range of climate change projections, in a stand located at N.E. Spain. We first use Bayesian inference to calibrate the GOTILWA + vegetation model against sap flow data for both tree species. We then project each tree species’ performance under several climate change scenarios. Our results indicate that increasing temperatures will enlarge black locust's vegetative period, leading to substantially increased annual productivity if the phreatic water table keeps reachable. For European ash, we project a slight increase in productivity, but with higher uncertainty. Our findings suggest that black locust will profit more from global warming than the native European ash, which is concerning because of the already detrimental impact of black locust for the local ecosystems. We conclude that climate change has the potential to stimulate black locust growth on Mediterranean riparian forests. Forest management should therefore include mechanisms to avoid black locust establishment, such as avoid clear-cutting and maintaining closed riparian forest canopies.

Differences in the community composition of nocturnal Lepidoptera between native and invaded forests are linked to the habitat structure

Non-native invasive plants are among the main threats to global biodiversity, including insects, and it is thus important to understand the mechanisms of how invasive plants impact native species. The community composition of nocturnal Lepidoptera was studied in the Czech Republic (Central Europe) in stands of native deciduous trees and in stands dominated by the invasive tree Robinia pseudoacacia, using automatic portable light traps together with an assessment of habitat characteristics. Native stands had more closed canopies and poorly developed understories. Conversely, R. pseudoacacia stands were more open and heterogeneous, with sparse canopies, well-developed shrub layers and a higher cover of taller herbs. Moth species richness, abundance and biomass were lower in R. pseudoacacia, likely due to the low richness of canopy herbivores not adapted to feed on the exotic host. However, feeding guilds associated with the understorey were more represented in stands of R. pseudoacacia, likely due to the more heterogeneous habitat structure. The Lepidopteran communities observed in stands of R. pseudoacacia resembled communities of open-forests or forest-steppe habitats. In contrast, native stands were dominated by Lepidoptera associated with trees, including forest specialists but also habitat generalists. From a conservation perspective, it appears that the invasive R. pseudoacacia created structurally more heterogeneous environment and more Lepidopteran open-forest guilds were associated with this habitat. However, further spread of R. pseudoacacia should be prevented because it reduces the species richness of Lepidoptera. Simultaneously, we recommend increasing the habitat heterogeneity of native forests to support functionally more diverse Lepidopteran communities.

Impacts of an invasive tree across trophic levels: Species richness, community composition and resident species’ traits

AbstractAimTo investigate the community‐level impacts of woody plant invasions using Robinia pseudoacacia as a model species, affecting organisms on different trophic levels: vascular plants, nocturnal Lepidoptera and birds.LocationCzech Republic, central Europe.MethodsNineteen plots with strong dominance of the invader were compared to 20 plots with native deciduous trees on sites with similar conditions. Species richness was compared using marginal models, species composition and the distribution of species traits by ordination analyses. Functional relationships between the three groups of organisms were investigated using a path analysis.ResultsOnly minor differences in species richness between invaded and uninvaded plots were detected for plants and birds, but the invaded stands hosted significantly fewer species of nocturnal Lepidoptera. On the contrary, all three groups differed in species composition and in the distribution of traits between the invaded and uninvaded stands. Nitrophilous plants, supported by human disturbances, were more represented in the invaded stands, while habitat specialist birds preferred uninvaded forest. Within nocturnal Lepidoptera, species of open habitats and fast life cycle preferred the invaded stands, and forest and canopy species and habitat generalists of larger sizes preferred the uninvaded stands. Path analysis showed a minor effect of R. pseudoacacia on the numbers of plants which were unrelated to species richness at higher trophic levels. However, R. pseudoacacia had a negative direct effect on nocturnal Lepidoptera, contributing to a weak negative indirect impact on birds.Main conclusionsThe impacts of R. pseudoacacia on species richness differed across the trophic levels, questioning the existence of simple cascading effects as a consequence of its invasion. Invasive plants do not always reduce the diversity of species per se, but cause shifts in species composition by replacing some of the pre‐invasion biota by species with traits enabling tolerance to the invaded habitat.

Composition of riparian litter input regulates organic matter decomposition: Implications for headwater stream functioning in a managed forest landscape.

Although the importance of stream condition for leaf litter decomposition has been extensively studied, little is known about how processing rates change in response to altered riparian vegetation community composition. We investigated patterns of plant litter input and decomposition across 20 boreal headwater streams that varied in proportions of riparian deciduous and coniferous trees. We measured a suite of in‐stream physical and chemical characteristics, as well as the amount and type of litter inputs from riparian vegetation, and related these to decomposition rates of native (alder, birch, and spruce) and introduced (lodgepole pine) litter species incubated in coarse‐ and fine‐mesh bags. Total litter inputs ranged more than fivefold among sites and increased with the proportion of deciduous vegetation in the riparian zone. In line with differences in initial litter quality, mean decomposition rate was highest for alder, followed by birch, spruce, and lodgepole pine (12, 55, and 68% lower rates, respectively). Further, these rates were greater in coarse‐mesh bags that allow colonization by macroinvertebrates. Variance in decomposition rate among sites for different species was best explained by different sets of environmental conditions, but litter‐input composition (i.e., quality) was overall highly important. On average, native litter decomposed faster in sites with higher‐quality litter input and (with the exception of spruce) higher concentrations of dissolved nutrients and open canopies. By contrast, lodgepole pine decomposed more rapidly in sites receiving lower‐quality litter inputs. Birch litter decomposition rate in coarse‐mesh bags was best predicted by the same environmental variables as in fine‐mesh bags, with additional positive influences of macroinvertebrate species richness. Hence, to facilitate energy turnover in boreal headwaters, forest management with focus on conifer production should aim at increasing the presence of native deciduous trees along streams, as they promote conditions that favor higher decomposition rates of terrestrial plant litter.

Response of understorey plant communities and traits to past land use and coniferous plantation

AbstractQuestionsHow did past land use and conifer plantation affect understorey plant communities? What plant traits explain understorey vegetation response to agricultural past land use and coniferous plantation?LocationForest of Orléans (50 000 ha), Loiret, north‐central France.MethodsCanopy cover, herb layer composition, litter and soil properties were measured in 80 100 m2 plots sampled in plantations of Pinus sylvestris or P. nigra vs natural regenerations of Quercus petraea and Q. robur along a gradient of forest continuity (using historical maps and aerial photos from 1840, 1949 and 2006). We related 15 plant traits to past land use and tree species using RLQ and fourth‐corner analyses.ResultsThe magnitude of past land use effect largely exceeded that of coniferous plantation. Post‐agricultural forests, even 150 yr after afforestation, differed from ancient forests in soil properties (thinner humus layer, higher P content, higher pH and lower C/N ratio) and plant traits. Ancient forests hosted more forest core species, stress‐tolerant, competitive species and bryophytes, but fewer ruderals, annuals/biennials, shrubs and trees and nutrient‐demanding species, and had lower SLA and higher LDMC. Conifer plantations had a thicker humus layer, lower pH and higher C/N ratio than deciduous forests, and hosted more light‐demanding species but less forest core species. Importantly, differences in soil and plant traits between conifer plantations and naturally regenerated deciduous stands were discernible in both recent and ancient forests, indicating that tree species lastingly influence ecosystem functioning.ConclusionsPast land use and coniferous plantation resulted in different understorey plant communities and traits under pine plantations and naturally regenerated oak stands. These differences were driven through soil acidification, litter decomposition rate, light conditions, canopy development, soil disturbance, stand management and dispersal and recruitment limitations. Coniferous plantations slowed down the recovery of post‐agricultural forests to ancient deciduous forest conditions. Applying natural regeneration and favouring native deciduous tree species thus helps recreate or maintain ancient forest plant communities.

GC-MS Analysis of Flowers of Millingtonia Hortensis L. F.

Millingtonia hortensis L.f. (Bignoniaceae) a native deciduous tree and is often cultivated as an ornamental tree in yards, garedens and avenues. The aim of the study to analyse bioactive phytoconstituents of flower extract of Millingtonia hortensis by GC-MS. The identified major compounds are Aspidoseprmidin 17-ol, 1-acety-19, 21epoxy-15, 16-dimethoxy (R.T: 27.90); 2-methyltetracosane (R.T: 28.24); Alfaxalone (R.T: 29.17); cis-13, 16-Docasdienoic acid (R.T: 30.86); Olean-12-ene-3, 15, 16, 21, 22, 28-hexol (R.T: 33.14); Stigmasta-5, 22-dien-3ol, acetate, (3β) (R.T: 34.20); β-Sitosterol (R.T: 35.72); Stigmasta-5, 24(28)-dien-3-ol, (3β) (R.T: 36.10); Betulin(R.T: 37.86). Preliminary phytochemical screening revealed the presence of flavonoids, glycosides, carbohydrate, phenolic compound and reducing sugar.

De novo assembly and characterization of Gleditsia sinensis transcriptome and subsequent gene identification and SSR mining.

Gleditsia sinensis is a Chinese native deciduous tree with a high economic and medicinal value. However, there is limited knowledge on the molecular processes responsible for the medical properties of this species owing to lack of bioinformatic resources such as available whole-genome sequences. In the present study, RNA sequencing data were used to analyze the transcriptome of G. sinensis, and a series of bioinformatic tools was used to explore the main genes involved in important molecular processes. A total of 75.57 million paired-end reads, with a length of 101 bp, were acquired from G. sinensis. Using the assembly tool Trinity, 233,751 transcripts were discovered. Among these, 85,795 were identified as unique transcripts and 59,326 unique transcripts were found to contain coding regions. Gene ontology analysis identified 27,637 unique transcripts that were clustered into 56 functional groups. Genes involved in flavonoid and terpenoid backbone biosynthesis and those encoding transcription factors were further analyzed. Sequence analysis revealed four putative G. sinensis chalcone isomerase genes (GsCHI) encoding the enzymes for flavonoid biosynthesis. GsCHI1 was found to be phylogenetically related to the chalcone isomerase of the family Leguminosae, and its transcript levels in different tissues were higher than those of GsCHI2, GsCHI3, and GsCHI4. Furthermore, 15,014 simple sequence repeat (SSR) markers were discovered in the transcript library, and 5170 primers were generated for the SSR loci. The genetic and genomic information presented in this study will be helpful for future studies on gene discovery and molecular processes in G. sinensis.