Forest Plant Communities Research Articles

Prescribed Burning Effect on the Richness, Diversity and Forest Structure of an Endemic Reforested Pinus canariensis Stand (Canary Islands)

Forest fires are considered to play a fundamental role in structuring many forest plant communities. Prescribed burning is a useful tool to reduce fire risk by reducing the amount of fuel. Our main objective was to analyse the effects of prescribed burning on undergrowth species richness and diversity as well as on other characteristic variables in a reforested Pinus canariensis stand. In areas where prescribed burning had been performed in the last 10 years, we established 8 plots of 900 m2. Their respective control plots were in nearby unburned and environmentally similar areas. We systematically selected 10 points in each plot and sampled the presence, richness and diversity of species in 1 m2 grids. For each plot, the basal area, mean canopy height and average height of individuals were measured. In centred 10 × 10 m plots, shrub species were counted as well as the litter depth, litter cover and herb cover. There was no significant change in the number of species richness found when comparing burned vs. control plots. Additionally, we did not find any differences in diversity or shrub composition, nor were we able to determine the species associated with any of the treatments. The basal area and litter depth were the only parameters that revealed significant differences. Ecologically, prescribed fire is a good practice to reduce biomass accumulation in P. canariensis plantations, with little effect on species richness and forest structure but with positive effects for stand management, insofar as biomass reduction can help control summer wildfires.

Plant functional traits predict heterogeneous distributional shifts in response to climate change

Abstract Climate change is causing the rapid redistribution of vegetation as plant species move to track their climatic optima. Despite a global trend of upward movement in latitude and elevation, there is extensive heterogeneity among species and locations, with few emerging generalizations. Greater generalization may be achieved from considering multidimensional changes in species' distributions as well as incorporating ecologically relevant functional traits into studies of range shifts. To better understand how recent changes in climate are influencing the elevational distribution of plant species and how species' functional traits mediate distributional changes, we resampled a 2438 m elevation transect spanning a distance of 16 km which encompasses desert scrub, pinyon‐juniper woodland, chaparral and coniferous forest plant communities. Over the last 42 years, total perennial cover and species' average cover increased at lower elevations and decreased at higher elevations while average elevational leading‐edge increased 116 m and elevational rear edge decreased 84 m. Notably, these changes were mediated by species' functional traits, where species exhibiting more conservative traits (lower specific leaf area [SLA], greater δ13C, larger seed mass) and taller height shifted upward in their leading‐edge range limit, average elevation and trailing edge range limit, while declining in abundance at the median and trailing edge of their range. Species possessing more acquisitive traits (higher SLA, lower δ13C, smaller seed mass) and shorter height shifted downward and increased in abundance at their trailing edge, with increases in their total range size. Our results provide clear evidence that heterogeneous range dynamics under recent climate change can be generalized by considering ecologically relevant plant functional traits, and how they respond to localized climate exposure. Furthermore, by documenting changes across a steep elevational gradient comprising a large aridity gradient, we show divergent patterns for plants occupying contrasting positions along the global spectrum of plant form and function, which provides critical insight into how trait‐mediated changes under increasing aridity will impact ecosystem functioning. Read the free Plain Language Summary for this article on the Journal blog.

Restoration of Vegetation Greenness and Possible Changes in Mature Forest Communities in Two Forests Damaged by the Vaia Storm in Northern Italy.

Windstorms are rare in the Southern Alps, but their frequency is increasing due to climate change. This research analyzed the vegetation of two spruce forests in Camonica Valley (Northern Italy) destroyed by the Vaia storm to evaluate the vegetation responses to blowdown damage. In each study area, the normalized difference vegetation index (NDVI) was used to evaluate the change in plant cover and greenness from 2018 (before the Vaia storm) to 2021. Furthermore, floristic-vegetation data were analyzed to identify current plant communities and develop models of plant succession. The results showed that the two areas, although located in different altitudinal vegetation belts, are undergoing the same ecological processes. NDVI is increasing in both areas, and pre-disturbance values (~0.8) should be reached in less than ten years. Nevertheless, the spontaneous restoration of pre-disturbance forest communities (Calamagrostio arundinaceae-Piceetum) should not occur in both study areas. In fact, the two plant succession trends are characterized by pioneer and intermediate stages with young trees of Quercus petraea and Abies alba, typical of more thermophilic mature forest communities compared to pre-disturbance ones. These results could reinforce the trend of the upward shift in forest plant species and plant communities in response to environmental changes in mountain areas.

Rethinking the nature of intraspecific variability and its consequences on species coexistence.

Intraspecific variability (IV) has been proposed to explain species coexistence in diverse communities. Assuming, sometimes implicitly, that conspecific individuals can perform differently in the same environment and that IV increases niche overlap, previous studies have found contrasting results regarding the effect of IV on species coexistence. We aim at showing that the large IV observed in data does not mean that conspecific individuals are necessarily different in their response to the environment and that the role of high-dimensional environmental variation in determining IV has largely remained unexplored in forest plant communities. We first used a simulation experiment where an individual attribute is derived from a high-dimensional model, representing "perfect knowledge" of individual response to the environment, to illustrate how large observed IV can result from "imperfect knowledge" of the environment. Second, using growth data from clonal Eucalyptus plantations in Brazil, we estimated a major contribution of the environment in determining individual growth. Third, using tree growth data from long-term tropical forest inventories in French Guiana, Panama and India, we showed that tree growth in tropical forests is structured spatially and that despite a large observed IV at the population level, conspecific individuals perform more similarly locally than compared with heterospecific individuals. As the number of environmental dimensions that are well quantified at fine scale is generally lower than the actual number of dimensions influencing individual attributes, a great part of observed IV might be represented as random variation across individuals when in fact it is environmentally driven. This mis-representation has important consequences for inference about community dynamics. We emphasize that observed IV does not necessarily impact species coexistence per se but can reveal species response to high-dimensional environment, which is consistent with niche theory and the observation of the many differences between species in nature.

Is it Possible to Indicate the Influence of Medieval Settlement Activities on Forest Phytocoenoses by Using 400 m2 Geobiocoenological Plots?

Abstract Many abandoned villages in Central Europe are now covered with forest. These abandoned villages can be indicated by their different species composition compared to the surroundings. We were interested in whether these differences could be indicated by geobiocoenological plots (400 m2). Phytocoenological samples were taken from geobiocoenological plots located on the former buildings, in the village square and in gardens. Based on significant fidelity (Fisher’s exact test at P = 0.05 significance level) and differential species coverage (ONE WAY ANOVA at P = 0.05 significance level), indicator species for the former buildings and former village square could be determined. The former buildings were indicated by species requiring higher soil nutrient content and higher pH, such as Anemone ranunculoides and Stachys sylvatica. The former village square site was indicated by species adapted to acid soils with less competitive abilities that could not compete on the more fertile soils of the former buildings, e.g. Maianthemum bifolium and Dryopteris carthusiana. Based on these results, it can be concluded that the influence of forest plant communities by medieval settlement activities can be phytoindicated using geobiocoenological plots of 400 m2. This method can be applied especially in areas with acid soils, e.g. where there is a large difference in the amount of plant-available nutrients in the soil

Biotic homogenization and differentiation of plant communities in tropical and subtropical forests.

Anthropogenic impacts on biodiversity can lead to biotic homogenization (BH) and biotic differentiation (BD). BH is a process of increasing similarity in community composition (including taxonomic, functional, and phylogenetic components), whereas BD is a process of decreasing similarity over space and time. Here, we conducted a systematic review of BH and BD in plant communities in tropical and subtropical forests to identify trends and knowledge gaps. Our bibliometric search in the Web of Science returned 1989 papers, of which 151 matched our criteria and were included in the analysis. The Neotropical region had the largest number of articles, and Brazil was the most represented country with 92 studies. Regarding the type of change, homogenization was more frequent than differentiation (noted in 69.6% of publications). The taxonomic diversity component was measured more often than functional and phylogenetic diversity components. Most studies (75.6%) assessed homogenization and differentiation based on a single observation in time; as opposed to few studies that monitored plant community over multiple years. Forest fragmentation was cited as the main determinant of homogenization and differentiation processes (57.2% of articles). Our results highlight the importance of evaluating community composition over time and more than taxonomic components (i.e., functional and phylogenetic) to advance understanding of homogenization and differentiation. Both processes were scale dependent and not mutually exclusive. As such, future research should consider differentiation as a potential transition phase to homogenization and that potential differences in both processes may depend on the spatial and temporal scale adopted. Understanding the complexity and causes of homogenization and differentiation is essential for biodiversity conservation in a world increasingly affected by anthropogenic disturbances.

Response of Plant Species Diversity to Flood Irrigation in the Tarim River Basin, Northwest China

This study quantitatively analyzes the effects of flooding on the growth and species diversity of riparian forests along the Yarkant River and the Tarim River, Xinjiang, in northwest China, and provides important information for the efficient utilization of water and water resource management in arid regions. Monitoring of species diversity of riparian forests was conducted every year from 2016 to 2019 in the Xiamale forest district in the lower reaches of the Yarkant River, and in the Shaya forest district and the lunnan forest district in the upper and middle reaches of the Tarim River. The Pielou index, Shannon–Wiener index, Simpson index, and importance value were used to analyze the influence of flooding. The results showed the following: (1) After three years of flooding, indices for the lower reaches of the Yarkant River and Tarim River were significantly increased and 11 new plant species appeared. (2) With increasing distance from the river channel, plant density and species diversity decreased. Flooding trends are the main factors affecting the distribution of plant species and water is the main restricting factor that influences plant growth in arid areas; thus, desert riparian forests improved significantly after flooding. (3) Flooding increases the regeneration capacity and species diversity of plant communities in desert riparian forests. In order to maintain the current trend of ecological improvement, flooding irrigation must continue.

The vertical form of the common ivy Hedera helix L. is associated with diverse and semi-natural forests in Central European highlands

Understanding the role of epiphytic vegetation and other microhabitats created by plants (hereafter lianas) developing on the surrounding ones is crucial for understanding the functioning of forest communities. Despite the observed increase in the biomass of lianas, the factors connected with forest plant communities determining their occurrence have not been investigated in a temperate zone. This research concerns the determinants of vertical form of the common ivy Hedera helix L. occurrence in highland forests in Central Europe. We established 69 pairs of sites, which consisted of areas inhabited by the vertical form of ivy and control areas (hereafter non-ivy plots). The sites with ivy were characterized by a higher volume (488 m3 ha-1 ± 251 SD vs. 411 m3 ha-1 ± 186 SD), a higher amount of deadwood (34 m3 ha-1 ± 39 SD vs. 23 m3 ha-1 ± 29 SD), and a higher tree species richness (8.0 species/ha ± 2.2 SD vs. 6.8 species/ha ± 2.14 SD) than non-ivy plots. The presence of vertical form of ivy was mainly influenced by a large share of alder in the stand and a higher diversity of trees and shrubs. Moreover, the number of large ivy vines increased with the presence of veteran trees. The presence of gaps was not conducive to the occurrence of large vines. The northern exposure and the presence of deadwood had a positive effect on the number of vines per tree. Our results contribute to the knowledge about variables influencing the occurrence and development of ivy vertical form in forests. The obtained results indicate that ivy requires diverse forests with a mix of trees and numerous veteran ones, which makes this species a good candidate as an indicator of forest habitat quality. We suggest that the common ivy should be protected within its native range and forest patches containing dense ivy vines should be excluded from silviculture.

Картографирование растительности южной части острова Сахалин по данным дешифрирования снимков спутниковой системы Landsat

The purpose of the research is to determine the factors that have a significant impact on the distribution structure of plant communities over the territory and to draw up a vegetation map. The article pre-sents the analytical results of the vegetation cover diversity and geobotanical mapping of the territory based on the data of decoded satellite images. Materials and methods. The main sources of information for the study are materials of field geobotanical studies and satellite images of medium spatial resolution obtained from the Landsat-8 satellite, which provided an assessment of the current state of forest communities. Modern compilation and design of maps is characterized by the widespread use of GIS technologies and computer analysis methods. To decrypt and process the images, the ENVI, ArcGIS, and QGIS software complexes were used. The final processing and design of the cartographic material was carried out using the Adobe Illustrator program. Results. The southern part of the Sakhalin Island territory was chosen as the object of research, on which a large number of east-asian species, including tree and shrub forms, grow. In the Yuzhno-Sakhalinsk floristic region, the flora of the North-Japanese type prevails, and the presence of northern species characteristic of the dark coniferous taiga zone is noticeably reduced in its composition. Krillionsky district is distinguished by the presence of species common with the Southern Kuril Islands and the Hokkaido Island. The re-sults of studying the spatial distribution of forest landscapes served as a basis for identifying the most resistant to climate change plant communities, as well as those capable of rapid recovery after forest fires. Climatic conditions have been analyzed, which made it possible to identify trends in the long-term dynamics of plant communities in the territory. The analysis of long-term dynamics made it possible to identify the current state of forest communities, predict certain negative natural phenomena (fires, waterlogging, etc.). Conclusions. The dynamics of the state of forest plant communities is clearly determined by the data of satellite surveys. The map, compiled on the basis of the results of space images interpretation, reflects the spatial distribution and state of the vegetation cover of the territory, enables to make an inventory of plant associations, to establish the boundaries of geobotanical regions in their current state.

Анализ динамики состояния лесных растительных сообществ в заказнике «Mакаровский» (Cахалин) по данным дистанционного зондирования земли

The results of the analysis of changes in the state of forest plant communities in the “Makarovsky” Nature Sanctuary in the period from 1980 to 2020 are presented in the article. In the process of our work there was created a model of the vegetation cover of the “Makarovsky” Sanctuary, which made it possible to determine the difference between plant communities and their condition. The data for the construction of the cartographic model were formalized spectral characteristics of the surface of plant communities recorded on Landsat-1–7 and Sentinel-2 images. In a specially protected natural area, 7 classes of objects have been identified when conducting uncontrolled classification using ArcGIS according by their spectral characteristics. The division of dark coniferous and deciduous forests, the identification of the boundaries of plots with different species composition of forest stands and the allocation of felling sites was performed on the basis of the normalized vegetation index (NDVI). The accuracy of determining the composition of forest stands based on the results of interpretation was checked by data of geobotanical research data on the territory of the “Makarovsky” Nature Sanctuary. As part of the vegetation cover of the “Makarovsky” Nature Sanctuary, 8 forest communities were identified—spruce-fir, stone-birch forests, cedar elfin formation, valley deciduous, birch, birch-spruce forests, woodlands, sometimes larch forests, and 2 non-forest communities—Kuril bamboo formation and meadow vegetation. Forest communities occupy 95 % of the territory of the “Makarovsky” Sanctuary. The landscape and climatic conditions of the area are optimal for the growth of spruce-fir forests, which cover 44 % of the total area of the “Makarovsky” Nature Sanctuary. Birch and stone-birch forests (39 %) are widespread on logged land in Sanctuary. There is a wide distribution of secondary succession in the territory of the “Makarovsky” Nature Sanctuary. The composition of forest stands in Sanctuary has changed significantly over the research period in favor of young coniferous trees. Vegetation in the “Makarovsky” Nature Sanctuary has preserved its natural pristine appearance and reflects both altitude differentiation and landscape-zonal features of the middle taiga subzone of Sakhalin. The use of satellite images of medium spatial resolution made it possible to accurately analyze the state of forests of the “Makarovsky” Sanctuary. More detailed researches require the use of unmanned aerial vehicles.

Субфоссильные спорово-пыльцевые спектры горных территорий на примере полуострова Камчатка

The article presents the results of the composition analysis of 27 recent (surface) pollen assemblages collected in typical plant communities in the northern part of the Central Kamchatka Depression and on the surrounding slopes of the Sredinny Range and Klyuchevskaya Sopka volcano. Our data show that spore-pollen spectra reliably represent the composition of forest plant communities. However, the proportions of pollen in the spectra of some arboreal taxas does not always correspond to their role in plant communities The adequacy of the spectra for plant communities is confirmed by cluster analysis, according to which the most statistically similar spore-pollen spectra are formed in similar plant communities. Regional components of the spectra in surface samples distort the ratios of main taxa in plant communities, especially in the high altitudinal vegetation belt. The participation of coniferous tree pollen in the spectra is underestimated compared to their actual presence in plant communities. These features must be considered when interpreting fossil spore-pollen spectra. Our materials made it possible to identify taxa whose pollen is often found in the spectra of the subalpine and alpine zones: Alnus alnobetula, Liliaceae, Polygonaceae, Asteraceae, Saussurea and Sanguisorba. The strongest influence of local vegetation is observed in the spectra of swamps and coastal plant communities. The spectra of these communities usually contain pollen of Alnus hirsuta, Salix, and Populus, as well as Rosaceae, Cyperaceae, Comarum, Myrica, and Menyanthes, and spores of Polypodiaceae and Equisetum. Our materials will facilitate more reasonable reconstructions of Kamchatka vegetation based on the pollen analysis in the study of fossil pollen spectra of the Kamchatka Peninsula, as well as in the interpretation of pollen data from other mountainous regions.

Biodiversity dynamics in primary mid-taiga spruce forests after total windthrow in the Vodlozersky National Park, Russia

In windthrow-affected areas, the research of biota is of high relevance taking into account the lack of knowledge about the dynamics of their flora, soil properties, and tree stand regeneration. An important task is to study the mechanisms of the natural dynamics of plant communities after major disturbances in large boreal forests. This paper was aimed to investigate the effects of a total windthrow event on the dynamics of biodiversity in pristine mid-boreal spruce (Picea abies) forests. The study was carried out in the Vodlozersky National Park (Northwest Russia: Arkhangelsk Region and Republic of Karelia), situated in the northern and middle taiga subzones. A series of permanent sample plots was established in an area affected by massive windthrow in 2000. The windthrow consequences of the forest communities have been studied, starting from the year of the event (2000) at 2–5-year intervals. A soil survey has been conducted in 2016. Windthrown trees, situated in the sample plots, were counted by species and diameter classes. Natural regeneration was estimated in subplots with a division to height cohorts and vitality status. Geobotanical relevé sampling of the ground vegetation has been conducted in 1 × 1-m permanent plots. Aphyllophoroid fungi (Basidiomycota) were counted by fruit bodies. Main soil pits and partial pits were dug. The morphological description of soils was produced in both undisturbed and disturbed sites in the study area. Obtained data, covering 20 years of surveys of various components of the forest plant communities (tree stand, advance regeneration, ground vegetation, wood-destroying fungi, soils), were analysed. We found that 16–20 years after the windthrow event the species and age structure of the tree stand has been considerably changed due to the forest stand rejuvenation. Post-windthrow regeneration of coniferous species in the true-moss group of forests has been successfully going on. By the end of the second decade after the windthrow event, cowberry spruce forests contained 4300 individuals/0.01 km2 of viable spruce regeneration, including 1500 individuals/0.01 km2 belonging to the large size category of spruce trees. In the bilberry-Sphagnum-type forest, spruce regeneration amounted to 8700 individuals/0.01 km2, including 2200 individuals/0.01 km2 belonging to the large size category of spruce trees. This amount is sufficient to ensure the development of spruce-dominated communities in the future. Since the forest ecosystems were recovering after the windthrow, the biodiversity of changed, that was reflected in an increase in the species composition of the ground vegetation and fungal communities. Over the study period (2001–2021), surveys of the sample plots demonstrated 83 aphyllophoroid fungi species, including five species included in the Red Data Book of the Republic of Karelia, as well as 22 taxa, considered old-growth forest indicator- and specialist species. The number of wood-destroying fungi species was the highest in the period from the 12th to the 19th post-windthrow years. The changes in soil properties on windthrow-affected sites were more explicit in the upper horizons: soil acidity decreased; both potassium and carbon content increased; nitrogen distribution across horizons became more even. An increase in the carbon-nitrogen ratio was detected in the Е and BF horizons. The obtained data can be used for predicting the regeneration of pristine mid-boreal spruce forests affected by catastrophic disturbances.

Divergent roles of herbivory in eutrophying forests

Ungulate populations are increasing across Europe with important implications for forest plant communities. Concurrently, atmospheric nitrogen (N) deposition continues to eutrophicate forests, threatening many rare, often more nutrient-efficient, plant species. These pressures may critically interact to shape biodiversity as in grassland and tundra systems, yet any potential interactions in forests remain poorly understood. Here, we combined vegetation resurveys from 52 sites across 13 European countries to test how changes in ungulate herbivory and eutrophication drive long-term changes in forest understorey communities. Increases in herbivory were associated with elevated temporal species turnover, however, identities of winner and loser species depended on N levels. Under low levels of N-deposition, herbivory favored threatened and small-ranged species while reducing the proportion of non-native and nutrient-demanding species. Yet all these trends were reversed under high levels of N-deposition. Herbivores also reduced shrub cover, likely exacerbating N effects by increasing light levels in the understorey. Eutrophication levels may therefore determine whether herbivory acts as a catalyst for the “N time bomb” or as a conservation tool in temperate forests.

A re-survey in 2019-2021 of winter bird communities in the Oregon Coast Range, USA, initially surveyed in 1968-1970.

Long-term changes in bird populations during winter are poorly evaluated in many parts of the world. We re-surveyed forest bird communities during winter, 2019-2021, in seven large plots originally surveyed from 1968 through to 1970, near Corvallis, Oregon, USA by Stanley Anderson, a graduate student at Oregon State University in the 1960s. Anderson counted birds and measured forest plant communities within the forests dominated by Douglas-fir (Pseudotsugamenziesii) in the Coast Range Mountain foothills. His thesis included plot locations, summaries of vegetation characteristics and point estimates of bird densities for each plot. To our knowledge, the Anderson data represent the oldest structured survey of Pacific Northwest winter forest bird communities with density estimates. Given the paucity of similar data, we re-surveyed his plots after aligning methods with his and adding modern components (distance and time interval sampling) to facilitate comparisons of changes in abundances. We preserved more extensive metadata than were preserved from Anderson's surveys, including georeferenced point count survey locations to facilitate more precisely repeatable future re-surveys. Original surveys of winter bird populations in the Pacific Northwest, USA, based on georeferenced locations within seven large plots originally surveyed, 1968-1970. In addition to raw count data of all bird species detected, we include information from distance sampling and time-interval sampling methods. To our knowledge, this is one of the only structured surveys of winter forest bird populations in the Coast Range Mountains, USA.

Litter eco-hydrological function characteristics of three typical plant communities in the area of Karst peak-cluster depressions from Guizhou, China.

Litter is an important component of forest ecosystems and plays an important eco-hydrological function. Many studies have been carried out on litter at present, but less research has been carried out on the eco-hydrological service functions of litter in different plant communities in Karst, especially in the area of Karst peak-cluster depressions in southwest China. To reveal the characteristics of the hydrological function of the litter layer of the plant community in the area of Karst peak-cluster depressions around FAST (Five-hundred-meter Aperture Spherical Radio Telescope), three typical plant community litter layers of the broad-leaved forest, coniferous forest, and shrub were selected as research objects, and the hydrological function of the litter layer of different plant community types was studied using the immersion method. The results indicated: 1) The litter layer of the broad-leaved forest plant community has the strongest function of intercepting and regulating precipitation (Mlmax = 24.17±0.33 t/ha, Msv = 19.93±0.21 t/ha), and its hydrological service function is the best. 2) The higher the decomposition degree of litter, the stronger the interception function. 3) The fitted equations for both the litter water-absorption capacity (Qct) and time (t) for plant communities were Qct = b + alnt, and the fitted equations for both the litter water-release capacity (Qst) and time (t) were Qst = a t b. 4) The fitted equations for both the water absorption and release rates (vc and vs) and time (t) of the litter were v = a t -b. The water absorption rates of litter were the fastest within 5 min (15529.01~22634.43 g/kg·h), with the greatest interception and storage function for short-term rainfall.

Carbon, Nitrogen and Phosphorus Stoichiometry and Its Influencing Factors in Karst Primary Forest

The stoichiometric characteristics of C, N, and P in plants result from long-term adaptation to environmental conditions. In this study, we analyzed leaf, branch, and soil C, N, and P stoichiometry in a karst primary forest plant community in China. The results showed that N and P content in leaves was higher than that in branches, while C content in the latter was higher than in leaves. Moreover, the coefficient of the variation in C, N, and P content in branches was greater than that in leaves but there was no significant difference in said coefficients in soil. The values of the C:N and C:P ratios were both branch > leaf > soil, whereas the value of the N:P ratio was leaf > branch > soil. There was also a significant positive correlation between leaf nitrogen (LN), leaf phosphorus (LP), branch nitrogen (BN), and branch phosphorus (BP) concentrations but no significant correlation between leaf carbon (LC), branch carbon (BC), and other element concentrations. We found that leaf stoichiometry was strongly influenced by species diversity, whereas branch stoichiometry was mainly influenced by leaf and species diversity; the environmental factors influencing the stoichiometric characteristics of leaves and branches were mainly altitude, soil pH, and total soil P. Finally, these results are relevant as they are helpful to understand the adaptation mechanisms and eco-geochemical processes in karst forest plants and they can also provide a scientific basis for vegetation restoration and reconstruction in these degraded ecosystems.

Endozoochorous seed dispersal by Korean water deer (Hydropotes inermis argyropus) in Taehwa Research Forest, South Korea

Endozoochorous seed dispersal by ungulates can facilitate the dispersal of seeds over long distances. Endozoochorous seed dispersal can also result in the ecological filtering of plant species by dispersing plant seeds with distinctive traits. The Korean water deer (Hydropotes inermis argyropus) is a potential long-distance seed dispersal vector in lowland areas of South Korea. In this study, to test the endozoochorous seed dispersal role of Korean water deer in forested areas, we collected 202 fresh fecal pellet group samples in Taehwa Research Forest, Gwangju City, Gyeonggi Province, South Korea. Additionally, we conducted a vegetation survey to compare the traits of dispersed seeds from feces with the seed traits of flora in the study site. To test whether the composition of species traits dispersed by endozoochory is consistent with that of lowland areas, which consist of forested hills, arable land, and wetlands, we compared the results with a former study conducted in the lowlands. From the seedling emergence method applied to feces, we found a total of 22 species and 115 seedlings. Among 202 fecal pellet groups, 19.8% had at least one germinable seed. Species of forbs, with small-sized seeds (≤2 mm in length), from open habitat, and seeds without special morphology for dispersal are most frequently dispersed through Korean water deer endozoochory. These traits were consistent with the former endozoochory study conducted in a lowland area, irrespective of the different available flora. Therefore, we suggest that deer can potentially disperse seeds with the aforementioned traits to forest plant communities, acting as a consistent ecological filter through endozoochory.

Stronger legacy effects of cropland than of meadows or pastures on soil conditions and plant communities in French mountain forests

AbstractQuestionDifferences in understorey vegetation between ancient and recent forests have been thoroughly explored; however, few studies have investigated the legacies of different former land uses in recent forests. Indeed, due to more intense agricultural practices (tillage and fertilisation), legacy effects are expected to be stronger in former cropland or meadows than in former pastures. Our objectives were to compare soil conditions, taxonomic composition and functional composition of understorey plant communities in recent forests located on former pastures, meadows or cropland, with ancient forests as a reference.LocationTarentaise Valley, Savoy, France.MethodsBased on land‐use maps surveyed between 1862 and 1864, we selected 82 forest sites with different former land uses in mountain forests in the French Alps and carried out soil sampling and botanical surveys. To account for potential confounding factors (altitude, canopy cover, tree species composition), we applied multiple linear regressions to analyse soil properties, canonical correspondence analysis to analyse plant taxonomic composition and multispecies generalised linear mixed‐effects models to analyse relationships between plant functional composition and former land uses.ResultsThe soils of former cropland were richer in nutrients and more alkaline compared to other past land uses, while soils on former pastures and meadows differed only slightly from ancient forests. Ancient forests were characterised by acidophilic, shade‐tolerant, low‐stature, forest‐dependent species, whereas former cropland was characterised by calcicolous non‐forest species. Former pasture and meadow communities displayed a distinct taxonomic composition compared to other past land uses, but a functional composition closer to ancient forest than to former cropland.ConclusionFormer cropland has a stronger legacy effect than former pastures or meadows. This could explain small differences between ancient and recent forests observed in previous studies conducted in mountain landscapes where former cropland was rare.

Effects of a native bamboo species on tree regeneration diversity of a subtropical Atlantic forest

The presence of native bamboo species is considered a factor that affects the dynamics of plant communities in tropical and subtropical forests. In southern Brazil, Merostachys skvortzovii is a long-lasting species (reproductive cycles of 32 years) highly dominant in disturbed areas, causing structural changes in the tree community. In this work, we assessed changes in regeneration communities in 11 years after a reproductive event of M. skvortzvii. We asked if canopy openness and time after bamboo reproduction affect taxonomic and functional diversities of regeneration communities. We installed 20 permanent plots were randomly distributed in the continuous canopy (CC) and open canopy (OC), measured bamboo culms density, and surveyed the regeneration community over the period 2008–2017, and used a generalized linear model to explore the effects of the environment and presence of bamboos on the diversity of regeneration community. We observed an increase in abundance, species richness, and beta diversity over time after the reproductive event, but the time did not affect the Shannon-Wiener index. The canopy opening positively affected the individual abundance species richness, beta diversity, Functional richness (FRic), Functional evenness (FEve) and Functional dispersion (FDis). Also, we found an effect of the canopy opening on the functional attributes positively affecting specific leaf area (SLA) and negatively affecting leaf mass area (LMA) and Leaf carbon content (LCC). We concluded that, despite the intense colonization after the reproduction, the bamboo population follows a decreasing dynamic without negative effects on the regeneration of subtropical forest species, which are more affected by the dynamics of the gaps than bamboo presence. These results show that the subtropical Atlantic Forest regeneration community can restructure itself in the understory without the need for bamboo management.

Increasing the intensity of regeneration treatments decreased beta diversity of temperate hardwood forest understory 20 years after disturbance

ContextIn temperate hardwood forests, increased intensity of soil and canopy disturbances tends to increase species richness due to the establishment of numerous early-successional plant species. However, while competitive pioneer species from early stages of succession can become recalcitrant and alter patterns of natural regeneration, very few studies have examined longer-term effects of these treatments on plant biodiversity.AimsIn this study, we investigated mid-term (ca. 20 years) effects of different regeneration treatments with varying soil and canopy disturbance intensities. We compared understory plant communities in temperate hardwood forests from all the South of Quebec (Canada).MethodsUsing circular experimental plots of 1962.5 m2 (radius = 25 m), we measured taxonomic and functional diversity indices and soil properties using four levels of disturbance intensity in six temperate hardwood forests of Quebec distributed along a longitudinal gradient. Reference forests, i.e. control forests with no silvicultural treatment known for ≥ 80 years, were compared to 20-year-old single-tree selection cuts, group-selection cuts and group-selection cuts with soil scarification.ResultsSpecies richness in both group-selection treatments was higher than that in reference forests. Plant equitability and beta diversity among sites in both group-selection treatments were lower than in single-tree selection cuts and control forests. More intense treatments contributed to the mid-term persistence of recalcitrant competitor species (e.g. Rubus idaeus L., Prunus pensylvanica L.f.) whereas soil scarification appears to have negative sustained effects on species known to be sensitive to regeneration treatments (e.g. Monotropa uniflora L., Dryopteris spinulosa Kuhn).ConclusionsIn temperate hardwood forests of Southern Quebec, silvicultural treatments of higher intensities resulted in detrimental effects on soil properties, especially in the surface horizon, 20 years after disturbance. This legacy, in turn, affected the composition and diversity of understory plant communities. The more intense silvicultural treatments contributed to the persistence of pioneer species better adapted to a wider range of environmental conditions and resulted in a decrease in understory plant community heterogeneity among sites. Conversely, single-tree selection cutting appeared to be the most appropriate silvicultural treatment for maintaining soil functions and heterogeneity of understory plant communities after 20 years; composition and structure being similar to long-undisturbed forests.