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The ecological importance of non-native species is the main characteristic of novel ecosystems. Pinus elliottii species is highly invasive in tropical forests and is commonly found in secondary forests in Brazil. We investigated the floristic and structural changes in an urban novel forest dominated by P. elliottii over a 13-year period (2011–2023). Based on the knowledge about novel forests ecology, we hypothesised that the community will remain stable without significant changes in tree structure and composition over the study period. We studied a small urban forest fragment (2 ha) in Juiz de Fora municipality, south-eastern Brazil. We measured all trees with diameter at breast height (DBH) ≥ 50 mm in a sample of 15 permanent plots (20 × 20 m) in 2011, 2016 and 2023, and calculated the changes in phytosociological and species diversity parameters for each period. As hypothesised, we did not observe significant changes in community structure and composition. Species richness increased from 63 to 80 over the period, but without changes in the phytosociological hierarchy. The non-native species P. elliottii remained as the most important species (importance value, IV) in 2011 (15.1%), 2016 (14.9%) and 2023 (14.2%). The following 12 hyperdominant species in the phytosociological hierarchy, which accounted for more than 70% of IV over the periods, remained dominant with no or small changes in the species hierarchy. The species diversity indices (H') and multivariate analysis (ANOSIM) did not show significant differences over the periods. We concluded that the community is likely to remain with no significant changes in the coming decades due of the self-regenerating structure of the main populations. To the best of our knowledge, this is the first dynamic analysis of an urban novel forest in the neotropics, providing valuable insights for a better understanding of its ecology and functioning. [ABSTRACT FROM AUTHOR]

Long-term monitoring is pivotal for the collection of data capable of unravelling spatio-temporal changes in plant diversity. Here we present a dataset including plant presence and abundance data collected using a probabilistic sampling design in the “Montagna di Torricchio” Strict Nature Reserve, central Apennines, Italy. Five surveys were conducted in 35 plots during a period spanning 22 years (2002–2024). This dataset allows for the study of plant diversity changes over space and time across different habitat types by using statistical inference based on solid sampling theory.

Questions: The alpine vegetation of the Alps is particularly vulnerable to climate change, as the temperature increase in this region is twice the global average and the available area for new colonisations decreases with increasing elevation. While numerous studies have investigated the response of vascular plants to a warming climate in the alpine belt, only a handful have investigated that of cryptogams in the European Alps. Based on a 21‐year monitoring project, we assessed the effects of climate change on cryptogams along elevation, from the treeline to the subnival belt. Location: Four GLORIA summits in Valais (Switzerland). Methods: Between 2001 and 2022, terricolous lichens and bryophytes (from 2008) were inventoried in 52 1‐m2 plots distributed across four summits: 2360 m a.s.l. (treeline), 2550 m (lower alpine), 2990 m (upper alpine) and 3210 m (subnival). Changes in species cover and richness were analysed using generalised linear mixed‐effects model (GLMMs). Results: For bryophytes, total cover remained stable overall. However, six species declined significantly between 2008 and 2022, and the species richness decreased after 2015. For terricolous lichens, total cover significantly increased on the lower alpine summit, while species richness increased on the upper alpine and subnival summits. Conclusions: Bryophytes have probably suffered from the increasingly dry conditions, with a succession of very warm and dry summers over the last decades. Terricolous lichens have taken advantage of the warmer conditions to increase their cover on the lower alpine summit, and new species have colonised the upper summits. However, as they compete with vascular plants for soil and light, they may suffer from shrub and tree encroachment in the future and will be limited upwards by the rarity of developed soils. The large topo‐climatic gradient (850 m) and the length of the time series suggest that similar trends are likely to be more widespread across the Alps. [ABSTRACT FROM AUTHOR]

Climate change portends serious implications for Arctic vegetation. Understanding these effects is likely to be enhanced with long-term observations from permanent plots. I evaluated three decades of change in tundra vegetation from 80 permanent plots on south-eastern Victoria Island, Nunavut, Canada. I compared baseline (1991 and 1992) and contemporary (2019 and 2022) periods in the cover and frequency of graminoids, mosses and common species of forbs, shrubs and lichens. I found substantial shifts in cover of several species and growth forms—an increase in graminoids, decreases in Dryas integrifolia, Polygonum viviparum and Saxifraga oppositifolia, and marginally significant declines in mosses and Cassiope tetragona, but no detectable changes in other groups. The decline in Dryas integrifolia was more pronounced at lower elevations and was noticeable as patches of apparent mortality, inside the plots and elsewhere. The shifts in species abundance were not significantly correlated with each other, nor with changes in soil depth. These changes, manifest as communities with more abundant graminoids, are consistent with expected climate change effects in colder regions of the Arctic. Repeated observations of permanent plots can aid in detecting and understanding long-term ecological change.

One of the largest remnants of tropical dry forest is the South American Gran Chaco. A quarter of this biome is in Paraguay, but there have been few studies in the Paraguayan Chaco. The Gran Chaco flora is diverse in structure, function, composition and phenology. Fundamental ecological questions remain in this biome, such as what bioclimatic factors shape the Chaco's composition, structure and phenology. In this study, we integrated forest inventories from permanent plots with monthly high-resolution NDVI from PlanetScope and historical climate data from WorldClim to identify bioclimatic predictors of forest structure, composition and phenology. We found that bioclimatic variables related to precipitation were correlated with stem density and Pielou evenness index, while temperature-related variables correlated with basal area. The best predictor of forest phenology (NDVI variation) was precipitation lagged by 1 month followed by temperature lagged by 2 months. In the period with most water stress, the phenological response correlates with diversity, height and basal area, showing links with dominance and tree size. Our results indicate that even if the ecology and function of Dry Chaco Forest is characterised by water limitation, temperature has a moderating effect by limiting growth and influencing leaf flush and deciduousness. [ABSTRACT FROM AUTHOR]

Evaluation of soil sustainability should take into account chemical and mineralogical changes due to cultivation. Potassium (K) application is a key farming practice that may potentially affect phyllosilicate composition and soil properties. Irrigation is another agent that affects soil composition. This study aims to evaluate the imprints of cultivation on the chemical and mineralogical compositions of lowland soils under semi-arid and Mediterranean climate regimes and to assess them with the natural pedogenesis. The sites examined include two permanent plot experiments with crop rotation, and three single-plant plots. Cultivated, control, and fallow soils were analyzed for their chemical and mineralogical composition. The X-ray diffraction patterns of the clay fraction were decomposed to achieve quantitative detection of changes among the illite–smectite (IS) phases and in kaolinite amounts. In loamy and clayey soils dominated by IS phases, cultivation caused minor changes and diverse behavior of the IS phases. Yet, the K balance was negative under high fertilization levels and higher plant mass production. Fertilization enhanced the natural process of transforming IS into kaolinite and illite in the sandy soil, leading to a positive K balance. This study emphasizes the importance of IS minerals as a dynamic K pool that responds to plant needs. [ABSTRACT FROM AUTHOR]

Due to the important role of forests in carbon neutrality, it is a big task in accurately calculating and predicting forest carbon storage and carbon sink capacity in recent years. However, considering the factors on the capacity of forest carbon sequestration, ecologists and foresters consider different models to evaluate the forest carbon sink ability at different scales, with foresters focusing more on forest growth models, while ecologists adding more climate and environmental factors, which may result in inconsistent results in carbon storage. Therefore, constructing an integrated model by combining the forestry and ecology models is essential for accurately quantifying and characterizing the forest carbon sink potential at the regional scale. Here, we proposed a new forest carbon sink potential index (FCSPI), which is defined as fractional deficiency of the current forest carbon to its maximum level, based on forest permanent plots, climate, and edaphic data to evaluate the forest sink potential ability from stand level to zonal scale across the northern subtropical zone in Hubei province, China, which coupled the stand growth model and climate-productivity model. The results at stand level showed that the R2 and RMSE of FCSPI were 0.78 and 0.072 respectively, which indicated that the FCSPI is an intuitive, highly practical, straightforward, easy, and rapid to implement methodology for forest carbon sequestration assessment. Moreover, FCSPI can conveniently extended from stand scale to zonal scale based on the site quality index for carbon sink (SIC) and stand age variables, which were derived from the opened climate, edaphic, and topographic data. The results of wall-to-wall FCSPI across the subtropical forest in Hubei province reveal the current and future carbon potential sequestration, which can help managers to focus on forest management for climate-smart actions and planning in forest ecosystem services framework.

(1) Background: Tropical Mountain forests (TMF) constitute a threatened major carbon sink due to deforestation. Carbon compensation projects could significantly aid in preserving these ecosystems. Consequently, we need a better understanding of the above-ground carbon (AGC) spatial distribution in TMFs to provide project developers with accurate estimations of their mitigation potential; (2) Methods: integrating field measurements and remote sensing data into a random forest (RF) modelling framework, we present the first high-resolution estimates of AGC density (Mg C ha−1) over the western Ecuadorian Andes to inform an ongoing carbon compensation mechanism; (3) Results: In 2021, the total landscape carbon storage was 13.65 Tg in 194,795 ha. We found a broad regional partitioning of AGC density mediated primarily by elevation. We report RF-estimated AGC density errors of 15% (RMSE = 23.8 Mg C ha−1) on any 10 m pixel along 3000 m of elevation gradient covering a wide range of ecological conditions; (4) Conclusions: Our approach showed that AGC high-resolution maps displaying carbon stocks on a per-pixel level with high accuracy (85%) could be obtained with a minimum of 14 ground-truth plots enriched with AGC density data from published regional studies. Likewise, our maps increased precision and reduced uncertainty concerning current methodologies used by international standards in the Voluntary Carbon Market. [ABSTRACT FROM AUTHOR]

How, where, and why carbon (C) moves into and out of an ecosystem through time are long-standing questions in biogeochemistry. Here, we bring together hundreds of thousands of C-cycle observations at the Harvard Forest in central Massachusetts, USA, a mid-latitude landscape dominated by 80–120-yr-old closed-canopy forests. These data answered four questions: (1) where and how much C is presently stored in dominant forest types; (2) what are current rates of C accrual and loss; (3) what biotic and abiotic factors contribute to variability in these rates; and (4) how has climate change affected the forest’s C cycle? Harvard Forest is an active C sink resulting from forest regrowth following land abandonment. Soil and tree biomass comprise nearly equal portions of existing C stocks. Net primary production (NPP) averaged 680–750 g C·m−2·yr−1; belowground NPP contributed 38–47% of the total, but with large uncertainty. Mineral soil C measured in the same inventory plots in 1992 and 2013 was too heterogeneous to detect change in soil-C pools; however, radiocarbon data suggest a small but persistent sink of 10–30 g C·m−2·yr−1. Net ecosystem production (NEP) in hardwood stands averaged ~300 g C·m−2·yr−1. NEP in hemlock-dominated forests averaged ~450 g C·m−2·yr−1 until infestation by the hemlock woolly adelgid turned these stands into a net C source. Since 2000, NPP has increased by 26%. For the period 1992–2015, NEP increased 93%. The increase in mean annual temperature and growing season length alone accounted for ~30% of the increase in productivity. Interannual variations in GPP and NEP were also correlated with increases in red oak biomass, forest leaf area, and canopy-scale light-use efficiency. Compared to long-term global change experiments at the Harvard Forest, the C sink in regrowing biomass equaled or exceeded C cycle modifications imposed by soil warming, N saturation, and hemlock removal. Results of this synthesis and comparison to simulation models suggest that forests across the region are likely to accrue C for decades to come but may be disrupted if the frequency or severity of biotic and abiotic disturbances increases.

The geomorphic processes in high-mountain environments are crucial and often limiting factors of vegetation development. Studies based on the long-term field monitoring are still scarce, however, thus limiting our understandng to vegetation dynamics and the knowledge needed for effective conservation management. In this paper we interpret results of a 20 years long observation considering the relationship between alpine vegetation and intensity of geomorphic processes in the territory of seven permanent plots in the Belianske Tatra Mts. (Slovakia, Central Europe). In principle, these sites represent a "battle field" for ongoing geomorphic processes and vegetation. They are either gradually occupied by initial stages of ecological succession of vegetation or were occupied in the past with the vegetation being more or less destructed. The field research was combined with data collection for standard phytosociological relèves. Spatial distribution of particular tussocks or individuals on each field was drawn in detail. We observed the share of species and their spatial arrangement in relation to the control sites with uncovered substrate. Special attention was paid to measuring the intensity of geomorphic processes using various methods and carried out three times a year. The CANOCO software was used for quantitative evaluation of the phytosociological relèves data. We applied indirect gradient analysis of principal components (PCA) to find out the variability of vegetation and sites, and the direct gradient analysis (RDA) to explain the diversity of species ad the habitat characteristicsThe geomorphic processes affecting the extreme high-mountain environment were evaluated as the most crucial elements that determine the spatial distribution of vegetation, its particular species or overall nature of coppice fragmentation. The relief and mainly its spatial geomorphic attributes are therefore relevant phenomena of landscape that enable scientists to understand, for example the scale and hierarchy of vegetation arrangement. The relationship of vegetation and the intensity of geomorphic processes can be only considered and generalized on the basis of longtermed research. [ABSTRACT FROM AUTHOR]

Question: Temperate grasslands are known for their high plant diversity and distinct seasonality. However, their intra‐annual community dynamics are still largely overlooked by ecologists. Therefore, we explored the seasonal alpha‐ and beta‐diversity patterns of vascular plants and their relationships to above‐ground biomass in a rocky steppe (Festucion valesiacae). Location: Pavlov Hills, SE Czech Republic. Methods: For one year, we monitored the plant community of the rocky steppe at monthly intervals in 42 permanent plots of 0.25 m2. We examined seasonal changes in above‐ground biomass (estimated from the cover and height of living plant parts) and seasonal beta‐diversity, which we partitioned into turnover and nestedness components and their quantitative counterparts: balanced changes and abundance gradients. Results: We identified a pronounced seasonal pattern of above‐ground biomass, species richness and composition. Total above‐ground biomass was highest in June (summer), with a peak representing only 60% of total annual production (sum of individual species' maxima). However, the observed peak in species richness occurred in March (early spring), with 80% of the total species number recorded throughout the year. Accordingly, nestedness and abundance gradient patterns differed in the spring months, while seasonal turnover and balanced changes in abundance were generally congruent. Annual, short‐lived, and perennial species exhibited different seasonal patterns of species richness and biomass production, although a sharp increase in biomass and a peak in species richness in spring were universal across the community. Conclusions: Seasonal climatic constraints on plant growth are key determinants of primary production dynamics. Plants adapt to these constraints by adjusting their life cycles in different ways. In dry grasslands, the complexity of plant responses to climatic seasonality can result in seasonal beta‐diversity patterns with divergent peaks in biomass and species richness. [ABSTRACT FROM AUTHOR]

Gypsum covers a vast area of the Iberian Peninsula, making Spain a leader in its production. Gypsum is a fundamental raw material for modern societies. However, gypsum quarries have an obvious impact on the landscape and biodiversity. Gypsum outcrops host a high percentage of endemic plants and unique vegetation, considered a priority by the EU. Restoring gypsum areas after mining is a key strategy to prevent biodiversity loss. For the implementation of restoration approaches, understanding vegetation's successional processes can be of invaluable help. To fully document the spontaneous succession in gypsum quarries and to evaluate its interest for restoration, 10 permanent plots of 20 × 50 m were proposed, with nested subplots, in which vegetation change was recorded for 13 years in Almeria (Spain). Through Species-Area Relationships (SARs), these plots' floristic changes were monitored and compared to others in which an active restoration was carried out, as well as others with natural vegetation. Furthermore, the successional pattern found was compared to those recorded in 28 quarries distributed throughout the Spanish territory. The results show that an ecological pattern of spontaneous primary auto-succession is widely recurring in Iberian gypsum quarries, which is capable of regenerating the pre-existing natural vegetation. [ABSTRACT FROM AUTHOR]

Forests contribute to climate change mitigation through carbon storage and uptake, but the extent to which this carbon pool varies in space and time is still poorly known. Several Earth Observation missions have been specifically designed to address this issue, for example, NASA's GEDI, NASA‐ISRO's NISAR and ESA's BIOMASS. Yet, all these missions' products require independent and consistent validation. A permanent, global, in situ, site‐based forest biomass reference measurement system relying on ground data of the highest possible quality is therefore needed. Here, we have assembled a list of almost 200 high‐quality sites through an in‐depth review of the literature and expert knowledge. In this study, we explore how representative these sites are in terms of their coverage of environmental conditions, geographical space and biomass‐related forest structure, compared to those experienced by forests worldwide. This work also aims at identifying which sites are the most representative, and where to invest to improve the representativeness of the proposed system. We show that the environmental coverage of the system does not seem to improve after at least the 175 most representative sites are included, but geographical and structural coverages continue to improve as more sites are added. We highlight the areas of poor environmental, geographical, or structural coverage, including, but not limited to, Canada, the western half of the USA, Mexico, Patagonia, Angola, Zambia, eastern Russia, and tropical and subtropical highlands (e.g. in Colombia, the Himalayas, Borneo, Papua). For the proposed system to succeed, we stress that (1) data must be collected and processed applying the same standards across all countries and continents; (2) system establishment and management must be inclusive and equitable, with careful consideration of working conditions; and (3) training and site partner involvement in downstream activities should be mandatory. [ABSTRACT FROM AUTHOR]

In 2021, a large transect with 281 10 × 10 m grid cells was re-surveyed in a limestone European beech forest (Hordelymo-Fagetum lathyretosum) on the plateau of the Göttingen Forest after surveys in 1981, 1991, 2001, and 2011. The stand, which has not been managed by forestry since the beginning of the permanent plot study, initially showed an increasing cover of the tree layer and, as a consequence of game-proof fencing until 2005, also an increasing cover of the shrub layer. Since 2011, the tree layer cover has decreased due to small openings after drought years and winter storms. Also, the shrub layer cover declined significantly since 2011, mainly due to ash dieback and the growing impact of deer browsing. In both vegetation layers, Fagus sylvatica was able to expand its dominant role. In the herbaceous layer, the sharp decline and loss of numerous species is striking, among them typical forest species that have been classified as characteristic for species-rich European beech forests on limestone (e. g., Lathyrus vernus, Mercurialis perennis). The large number of losers (27 species) is matched by only a small number of winners (5 species) between 1981 and 2021. Especially Allium ursinum and Hedera helix, but also the two Orchidaceae Epipactis helleborine and Neottia nidus-avis have increased significantly since 1981. The increase of the highly competitive Allium ursinum, probably due to an earlier start and a longer lasting vegetation period, is accompanied by an increasing share of beech in the tree layer. At the same time, the species diversity decreased, and the herb layer composition became more homogeneous across the transect. Hedera helix seems to have benefited mainly from climate change (lack of severe winter frosts, CO2 increase), but also from the temporary exclusion of roe deer browsing. Based on the analysis of mean indicator values shade-tolerant, oceanic-distributed species, as well as nitrogen and moisture indicators have increased, while more light demanding species continuously decreased between survey years. Compared to intensively managed stands with massive thinning and/or soil disturbances, as in coppice-with-standards or large shelterwood systems, these species suffered from a closed canopy after management abandonment. The small-scale disturbances caused by drought and windthrow in the period 2012-2021 are obviously not sufficient to provide favourable conditions for these species, including a large number of species that have been classified as typical for European beech forests on limestone and that have been present in the beginning of the longterm study. Thus, the presented time series indicates that eutrophic beech forests without forest management are species poorer than previously reported. [ABSTRACT FROM AUTHOR]

Understanding forest dynamics is fundamental to their ecological restoration. This is particularly important in forests rich in species of commercial value, such as those of the Juglans genus, which known allelopathic effect could have an impact on the diversity of locations where it exists. The objective of this study was to evaluate the floristic composition and tree diversity of a forest dominated by Juglans neotropica Diels, establishing a permanent plot of 100 x 100 m in the Chanchamayo valley. In the plot, all trees were evaluated with DBH = 10 cm. The permanent plot presented 300 individuals, which corresponded to 47 species in 20 families. The Fisher's Alpha diversity index value was 15.62, and the Shannon-Wiener index value 1.65. These values are notoriously low in comparison with similar sites located in tropical premontane forests referred to in the present work. Due to the allelopathic nature of J. neotropica Diels, it is possible that this condition is a determining factor for the high abundance of this species in the plot and the low tree diversity identified. Since J. neotropica Diels is categorized as endangered by IUCN, the area becomes an important location for its conservation and that of its gene pool. [ABSTRACT FROM AUTHOR]

A study was carried out in five-year-old plantations of Tectona grandis located in the Amazon region of Peru, in order to evaluate the response in growth, productivity, silvicultural indices, and quality. Nineteen permanent monitoring plots in 20.7 ha distributed in four zones were evaluated. The dasometric parameters determined the quantitative variables, while the weighting of the qualitative variables determined the initial quality of the plantation. The results show a plantation of good quality and stable thickness, with high growth and productivity values, reporting diameters of 16.93 cm and heights of 13.27 m. The mean annual increases in diameter and height were 3.39 cm.yr-1 and 2.66 m.yr-1, respectively. Moreover, a mean annual volumetric increase of 16.109 m³.ha-1.yr-1 was obtained. This study contributes to decision-making for the planning of silvicultural activities, and it shows the behavior of teak for future plantations in the region. [ABSTRACT FROM AUTHOR]

Climate change portends serious implications for Arctic vegetation. Understanding these effects is likely to be enhanced with long-term observations from permanent plots. I evaluated three decades of change in tundra vegetation from 80 permanent plots on south-eastern Victoria Island, Nunavut, Canada. I compared baseline (1991 and 1992) and contemporary (2019 and 2022) periods in the cover and frequency of graminoids, mosses and common species of forbs, shrubs and lichens. I found substantial shifts in cover of several species and growth forms—an increase in graminoids, decreases in Dryas integrifolia, Polygonum viviparum and Saxifraga oppositifolia, and marginally significant declines in mosses and Cassiope tetragona, but no detectable changes in other groups. The decline in Dryas integrifolia was more pronounced at lower elevations and was noticeable as patches of apparent mortality, inside the plots and elsewhere. The shifts in species abundance were not significantly correlated with each other, nor with changes in soil depth. These changes, manifest as communities with more abundant graminoids, are consistent with expected climate change effects in colder regions of the Arctic. Repeated observations of permanent plots can aid in detecting and understanding long-term ecological change. [ABSTRACT FROM AUTHOR]

We present a data set resulting from the first round of a national monitoring program of forest reserves. It contains 9538 permanent plots, distributed across 111 study sites in mainland France (including Corsica). Notably focusing on dead wood measurement, this protocol has primarily been applied in strict forest reserves and special nature reserves (sensu Bollmann & Braunisch 2013), with 68% (6494) of the plots being currently located in strict forest reserves (unmanaged) and 24.7% (2363 plots) in forests unmanaged for at least 50 years. Sites cover a large variety of ecological conditions, from lowland to subalpine forests, but with an underrepresentation of Mediterranean forests (Table 1). The protocol assesses all the stages of a tree's life cycle, from seedling to decomposed lying dead wood. On each plot, a combination of three sampling techniques was used: (1) fixed‐area inventory for regeneration, standing dead trees, living trees, and coarse woody debris (CWD) with diameter over 30 cm; (2) transect lines for CWD with diameter <30 cm; and (3) fixed‐angle plot method for living trees with diameter at breast height (DBH) >30 cm (using a relascopic angle of 3%). Measurements include exact tree location (azimuth, distance), species, diameter(s), tree‐related microhabitats, decay stage and bark cover, and seedling cover. With ongoing climate change, the program network can also provide important information to monitor changes in forest ecosystems. It can also be used as forest management monitoring or conservation status assessment. These data are freely available for noncommercial scientific use (Creative Commons Attribution 4.0 CC BY SA 4.0) with attribution, and this paper must be cited if this material is reused. [ABSTRACT FROM AUTHOR]

Mountain birch forest covers large areas in Eurasia, and their ecological resilience provides important ecosystem services to human societies. This study describes long‐term stand dynamics based on permanent plots in the upper mountain birch belt in SE Norway. We also present forest line changes over a period of 70 years. Inventories were conducted in 1931, 1953, and 2007. Overall, there were small changes from 1931 up to 1953 followed by a marked increase in biomass and dominant height of mountain birch throughout the period from 1953 to 2007. In addition, the biomass of spruce (Picea abies) and the number of plots with spruce present doubled. The high mortality rate of larger birch stems and large recruitment by sprouting since the 1960s reveal recurrent rejuvenation events after the earlier outbreak of the autumnal moth (Epirrita autumnata). Our results demonstrate both a high stem turnover in mountain birch and a great ability to recover after disturbances. This trend is interpreted as regrowth after a moth attack, but also long‐term and time‐lagged responses due to slightly improved growth conditions. An advance of the mountain birch forest line by 0.71 m year−1 from 1937 to 2007 was documented, resulting in a total reduction of the alpine area by 12%. Most of the changes in the forest line seem to have taken place after 1960. Regarding silviculture methods in mountain birch, a dimension cutting of larger birch trees with a cutting interval of c. 60 years seems to be a sustainable alternative for mimicking natural processes. [ABSTRACT FROM AUTHOR]

Societal Impact Statement Tropical dry forests (TDF) underpin the wellbeing of millions, mostly rural populations; yet have suffered from severe clearing in Colombia, triggering cascading effects such as desertification. By engaging scientists, society, and institutions in the establishment of platforms for monitoring biodiversity and ecosystem functioning, crucial knowledge gaps will be bridged, helping to find a path toward sustainable development. Science‐led but socially and economically anchored information on biodiversity will help to incorporate nature's contributions to people into the society's cultural values. Ultimately, these transformative actions will translate into the comprehensive management of TDF through a greater impact in decision making. Summary Thousands of permanent plots have been established across the tropics with the purpose of monitoring tree communities. Research outcomes from these platforms, however, have been mainly directed toward the academic community, and their contribution to society has been limited so far. Here, we show how generating robust data on biodiversity has supported decision making in Colombian tropical dry forests (TDF), where less than 8% of their original cover remains. As a first step to build a national dialogue around the critical status of this ecosystem, a national collaborative network on TDF research and monitoring was born in 2014, the Red de Investigación y Monitoreo del Bosque Seco Tropical en Colombia (Red BST‐Col). Our main goal is to generate scientifically sound information that feeds into the comprehensive management of this ecosystem. To do so, a set of biodiversity monitoring platforms has been established across the country, which have already served to answer socio‐ecological questions related with deforestation drivers, citizen science, or the valuation of ecosystem services. Overall, this research agenda has nurtured the four lines that underpin the Program for the comprehensive management of dry forests in Colombia (knowledge management, preservation, restoration, and sustainable use), formulated by the Humboldt Institute, the United Nations Development Programme, and the Ministry of Environment in 2019. Many challenges are ahead, however, for a complex territory where multiple social actors and productive sectors coexist. The ultimate goal is to integrate all the dimensions of biodiversity to achieve a synthetic understanding of the functioning of the most endangered ecosystem in Colombia, and its relationship with local communities' wellbeing.

This study is focused on the vegetation of seminatural dry grasslands. These grasslands are valuable with large biodiversity; however, their long-term preservation requires regular conservation management. This report demonstrates the results of a 13-years mowing experiment, designed to suppress the spread of an unpalatable grass species, Calamagrostis epigejos. The study site was located in mid-successional grasslands, in the Western-Cserhát, near Rád, Northern Hungary. The experimental design consisted of eight permanent plots, where mowing was applied twice a year. The vegetation was sampled annually (from 2001 to 2013). The impacts of mowing were tested using repeated–measures analyses of variance (ANOVA). In 2001, Calamagrostis epigejos was the species with the highest cover in both the mown and control sites, with an average cover value of 63%. However, as a result of mowing, a significant difference was detected in the amount of litter and legumes species as well. The number of species showed an increase in both types of treatment, from 15 to 37 in the mowed plots, but also from 18 to 27 in the control plots. We concluded that mowing twice a year proved to be a useful measure for modifying botanical composition of a grassland. It was well suited for agricultural usage, in particular grazing, which can replace the expensive and time-consuming scythe. Mowing can also be a suitable management measure for controlling native invader species such as Calamagrostis epigejos, and can significantly increase the proportion of species with higher forage values. [ABSTRACT FROM AUTHOR]

This article evaluates the three-year vegetation dynamics of a species rich, protected steppe grassland on loess where no grazing occurred for decades at Bicske, Central Hungary. A detailed coenological survey of vascular vegetation was conducted in four permanent plots of 16 m2 each from 2018 to 2020. Raunkiaer's life-forms, distribution range, and thousand-seed weight of species were evaluated. Shannon diversity and turnover rates for the species and the vegetation were also determined for each plot. In total, 108 vascular plant species were detected. The results indicate grassland stability when plant traits spectra were based on species presence data, but directional change if species cover values were used to weight trait categories. During the three years of the study, chamaephytes decreased and woody species increased their contribution for the Raunkiaer's life-forms, while the cosmopolitan group has steadily lost its significance for distribution range types. Shannon diversity varied between 2.46 and 3.18 among plots (based on natural logarithm) and remained statistically unchanged through time. Average species turnover rates were 14.18% for 2018/19 and 17.52% for 2019/20, whereas corresponding values for vegetation turnover rates were 25.83% and 23.28%. Vegetation turnover rate was significantly higher than the species turnover rate. [ABSTRACT FROM AUTHOR]

Analysing temporal patterns in plant communities is extremely important to quantify the extent and the consequences of ecological changes, especially considering the current biodiversity crisis. Long‐term data collected through the regular sampling of permanent plots represent the most accurate resource to study ecological succession, analyse the stability of a community over time and understand the mechanisms driving vegetation change. We hereby present the LOng‐Term Vegetation Sampling (LOTVS) initiative, a global collection of vegetation time‐series derived from the regular monitoring of plant species in permanent plots. With 79 data sets from five continents and 7,789 vegetation time‐series monitored for at least 6 years and mostly on an annual basis, LOTVS possibly represents the largest collection of temporally fine‐grained vegetation time‐series derived from permanent plots and made accessible to the research community. As such, it has an outstanding potential to support innovative research in the fields of vegetation science, plant ecology and temporal ecology. [ABSTRACT FROM AUTHOR]

Gypsum covers a vast area of the Iberian Peninsula, making Spain a leader in its production. Gypsum is a fundamental raw material for modern societies. However, gypsum quarries have an obvious impact on the landscape and biodiversity. Gypsum outcrops host a high percentage of endemic plants and unique vegetation, considered a priority by the EU. Restoring gypsum areas after mining is a key strategy to prevent biodiversity loss. For the implementation of restoration approaches, understanding vegetation’s successional processes can be of invaluable help. To fully document the spontaneous succession in gypsum quarries and to evaluate its interest for restoration, 10 permanent plots of 20 × 50 m were proposed, with nested subplots, in which vegetation change was recorded for 13 years in Almeria (Spain). Through Species-Area Relationships (SARs), these plots’ floristic changes were monitored and compared to others in which an active restoration was carried out, as well as others with natural vegetation. Furthermore, the successional pattern found was compared to those recorded in 28 quarries distributed throughout the Spanish territory. The results show that an ecological pattern of spontaneous primary auto-succession is widely recurring in Iberian gypsum quarries, which is capable of regenerating the pre-existing natural vegetation.

Despite great concern for drought‐driven forest mortality, the effects of frequent low‐intensity droughts have been largely overlooked in the boreal forest because of their negligible impacts over the short term. In this study, we used data from 6876 permanent plots distributed across most of the Canadian boreal zone to assess the effects of repeated low‐intensity droughts on forest mortality. Specifically, we compared the relative impact of sequential years under low‐intensity dry conditions with the effects of variables related to the intensity of dry conditions, stand characteristics, and local climate. Then, we searched for thresholds in forest mortality as a function of the number of years between two forest surveys affected by dry conditions of any intensity. Our results showed that, in general, frequent low‐intensity dry conditions had stronger effects on forest mortality than the intensity of the driest conditions in the plot. Frequent low‐intensity dry conditions acted as an inciting factor of forest mortality exacerbated by stand characteristics and environmental conditions. Overall, the mortality of forests dominated by shade‐tolerant conifers was significantly and positively related to frequent low‐intensity dry conditions, supporting, in some cases, the existence of thresholds delimiting contrasting responses to drought. In mixtures with broadleaf species, however, sequential dry conditions had a negligible impact. The effects of frequent dry conditions on shade‐intolerant forests mainly depended on local climate, inciting or mitigating the mortality of forests located in wet places and dominated by broadleaf species or jack pine, respectively. Our results highlight the importance of assessing not only climate‐driven extreme events but also repeated disturbances of low intensity. In the long term, the smooth response of forests to dry conditions might abruptly change leading to disproportional mortality triggered by accumulated stress conditions. Forest and wildlife managers should consider the cumulative effects of climate change on mortality to avoid shortfalls in timber and habitat. [ABSTRACT FROM AUTHOR]

Re-inventory of lianas were performed in two 1-ha permanent plots at a 19-year interval (2001-2020) in two tropical dry evergreen forest sites (TDEF; Oorani -OR and Puthupet - PP) of Coromandel Coast of India. Overall, 1964 lianas representing 30 species belonging to 24 genera and 18 families were recorded in this study. Liana species richness declined in both the sites since initial inventory. The TDEF sites revealed an overall increase in stem density for the families Loganiaceae, Papilionaceae, Tiliaceae, Combretaceae, and Celastraceae. The site PP subjected to extreme anthropogenic disturbances reported considerable decrease in its stem density. The diameter class 1-3 cm also revealed substantial decline in its stem density. The endemic species Derris ovalifolia showed an increase in its stem density in 19 years. Anthropogenic disturbances resulted in significant decrease in abundance of species such as Gymnema sylvestre and Jasminum angustifolium, which are known for their medicinal value. The present results provide insights on how anthropogenic disturbances alter species diversity, abundance, and resource values of lianas in TDEFs over a period of time, which will certainly be beneficial for proposing management strategies in the conservation of this forest type. [ABSTRACT FROM AUTHOR]

Disentangling the relative influence of background versus disturbance related mortality on forest demography is crucial for understanding long‐term dynamics and predicting the influence of global change on forests. Quantifying the rates and drivers of tree demography requires direct observations of tree populations over multiple decades, yet such studies are rare in old‐growth forest, particularly in the temperate zone of Europe. We use multi‐decade (1980–2020) monitoring of permanent plots, including observations of mode of mortality and disturbance events, to quantify rates and drivers of tree demography across a network of old‐growth remnants in temperate mountain forests of Slovenia. Annual rates of mortality and recruitment varied markedly among sites and over time; census intervals that captured intermediate severity canopy disturbances caused subtle peaks in annual mortality (e.g., >2%/year), while rates of background mortality in non‐disturbed intervals averaged about 1%/year. Roughly half of the trees died from modes of mortality associated with disturbance (i.e., uprooting or snapped‐alive). Results of a Bayesian multilevel model indicate that beech (Fagus sylvatica) had a higher likelihood of disturbance related mortality compared to fir (Abies alba), which mainly died standing, and there was a notable increase in the odds of disturbance mortality with increasing diameter for all species. Annual recruitment rates were consistently low at sites (<0.5%) that lacked evidence of disturbance, but often exceeded 3% on sites with higher levels of past canopy mortality. Recruitment was dominated by beech on sites with more diffuse background mortality, while the less shade tolerant maple (Acer pseudoplatanus) recruited following known disturbance events. Our study highlights the important role of stand‐scale, partial canopy disturbance for long‐term forest demography. These results suggest that subtle climate‐driven changes in the regime of intermediate severity disturbances could have an important influence on future forest dynamics and warrant attention. [ABSTRACT FROM AUTHOR]

An emerging method of monitoring biodiversity is through the use of audio recordings, often made by autonomous recording units. Acoustic indices have been developed to estimate animal diversity, especially across human disturbance gradients, and have been shown to often correlate with manual counts of animals. Less work has examined whether acoustic indices can detect finer-scale habitat gradients, such as differences in vegetation within mature forests, especially using long-term vegetation plots. We used autonomous recorders to capture sound predominantly produced by birds in the morning and insects at night across a network of 27 1-ha forest vegetation plots, located between 300 and 1850 m asl in southern China, collecting 38,200 min of sound recordings. Based on the animal diversity literature, we hypothesized that acoustic indices would have strongest relationships with elevation, intermediary relationships with vertical structure (vertical heterogeneity, canopy height and tree density), and the weakest relationships with tree species diversity. Generalized linear mixed models, followed by model averaging, showed that elevation was indeed the strongest of the predictor variables, with the highest mean importance factor. In 6 of 14 models the coefficients had confidence intervals that did not cross zero, and in all such significant relationships acoustic diversity decreased with elevation. Vertical heterogeneity had the second highest mean importance factor, but one of its two significant relationships was negative. The only other significant relationship was a positive one between tree species diversity and the H index. Morning and evening recordings had similar results, despite representing biophony made by different taxa with different acoustic characteristics. However, the seven acoustic indices gave dissimilar results, with the H index having three significant relationships, compared to the ACI, BIO and AR indices that had none. We conclude that autonomous recorders, if analyzed with multiple acoustic indices, can be used to investigate landscape or vegetation-related gradients that may influence animal diversity on long-term vegetation plots.

Na podstawie zdjęć fitosocjologicznych z 52 powierzchni stałych w Kampinoskim Parku Narodowym, wykonanych w latach 2001, 2007, 2012 i 2018, określono główne kierunki zmian składu gatunkowego i wskaźników struktury runa. Podobieństwo składu gatunkowego między powierzchniami w latach 2001 i 2018 umożliwiło wyróżnienie czterech grup powierzchni: A - zbiorowiska o różnym stopniu wykształcenia występujące na siedliskach olsowych, B - bory i bory mieszane, C - grądy i zbiorowiska zbliżone oraz D - różne stadia sukcesyjne od zbiorowisk nieleśnych do lasu. Każda z grup charakteryzowała się swoistym zestawem cech zmieniających się w sposób kierunkowy. Ponadto dla każdej z nich inaczej kształtują się zależności korelacyjne między cechami roślinności i cechami gleby, a parametry modeli korelacyjnych mogą być istotnie różne dla różnych lat pomiarowych. Zaobserwowane korelacje między cechami roślinności a poziomem wody mają charakter ogólny, wynikający ze zróżnicowania między grupami zbiorowisk. Nie zaobserwowano natomiast związków między wzrostem poziomu wody a zmianami kierunkowymi cech roślinności ani w ujęciu ogólnym, ani w obrębie grup. Osiemnastoletni okres pomiarowy umożliwia śledzenie krótkoterminowych zmian w fitocenozach, ale jest zbyt krótki, aby stwierdzić występowanie wielkoobszarowych procesów wywołanych regionalnymi lub globalnymi zmianami środowiska, w tym klimatu. Specyfiką metodyczną opracowania było uwzględnienie tylko zmian systematycznych, prowadzących z okresu na okres w tym samym kierunku. Ujęcie bilansowe (różnica między pierwszym i ostatnim pomiarem) wskazuje na zmiany znacznie większej liczby charakterystyk, ale maskuje procesy fluktuacji w okresach dziesięcio- i piętnastoletnich. [ABSTRACT FROM AUTHOR]

Aim: Old‐growth, mesic temperate forests are often assumed to be structured by gap‐phase processes, resulting in quasi‐equilibrial long‐term dynamics. This assumption influences management focused on simulation of natural disturbance dynamics and is embedded in most models of forest successional dynamics. We use multi‐decade monitoring of permanent plots in old‐growth forests to assess demographic assumptions directly with respect to tree mortality rates. Location: Sixteen sites in mesic, temperate old‐growth forests in eastern North America and Europe with multi‐decade monitoring. Time period: Variable across sites, spanning c. 20–78 years from 1936 to 2014. Major taxa studied: Tree species of late‐successional, cool‐temperate forests of Europe and eastern North America. Methods: We calculated and compared the annualized mortality rates (m), with confidence intervals, by species, size class and measurement interval, for tree species of sufficient abundance. Results: Retrospective analysis shows dynamic and diverse demographic properties across populations and sites. Stand‐scale mortality rates of 0.7–2.5%/year average higher than previous estimates for old‐growth temperate forests. Variations among species, over time and among size classes, suggest that gap‐phase models are inadequate to explain stand dynamics, implying instead that rare disturbance events of moderate severity have long‐lasting effects in old‐growth forests and that indirect anthropogenic influences affect old‐growth, unlogged forests. Main conclusions: Multi‐decade baseline data, essential for understanding community assembly and long‐term dynamics in these "slow systems," are rare and poorly integrated. Our analysis demonstrates the value of the few long‐term, "legacy" data sets. Results suggest that differences in life history interact with complex disturbance histories, resulting in non‐equilibrial dynamics in old‐growth temperate tree communities, and that changes in disturbance patterns through anthropogenic climate change might, therefore, be an important driver of ecosystem change. [ABSTRACT FROM AUTHOR]

Warming temperatures and rising moisture deficits are expected to increase the rates of background tree mortality–low amounts of tree mortality (~0.5%–2% year−1), characterizing the forest demographic processes in the absence of abrupt, coarse‐scale disturbance events (e.g. fire). When compounded over multiple decades and large areas, even minor increases in background tree mortality (e.g. <0.5% year−1) can cause changes to forest communities and carbon storage potential that are comparable to or greater than those caused by disturbances.We examine how temporal variability in rates of background tree mortality for four subalpine conifers reflects variability in climate and climate teleconnections using observations of tree mortality from 1982 to 2019 at Niwot Ridge, Colorado, USA. Individually marked trees (initial population 5,043) in 13 permanent plots—located across a range of site conditions, stand ages and species compositions—were censused for new mortality nine times over 37 years.Background tree mortality was primarily attributed to stress from unfavourable climate and competition (71.2%) and bark beetle activity (23.3%), whereas few trees died from wind (5.3%) and wildlife impacts (0.2%). Mean annualized tree mortality attributed to tree stress and bark beetles more than tripled across all stands between initial censuses (0.26% year−1, 1982–1993/1994) and recent censuses (0.82% year−1, 2008–2019). Higher rates of tree mortality were related to warmer maximum summer temperatures, greater summer moisture deficits, and negative anomalies in ENSO (La Niña), with greater effects of drought in some subpopulations (tree size, age and species). For example, in older stands (>250 years), larger and older trees were more likely to die than smaller and younger trees. Differences in tree mortality rates and sensitivity to climate among subpopulations that varied by stand type may lead to unexpected shifts in stand composition and structure.Synthesis. A strong relationship between higher rates of tree mortality and warmer, drier summer climate conditions implies that climate warming will continue to increase background mortality rates in subalpine forests. Combined with increases in disturbances and declining frequency of moist‐cool years suitable for seedling establishment, increasing rates of tree mortality have the potential to drive declines in subalpine tree populations. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Tropical dry forests (TDF) underpin the wellbeing of millions, mostly rural populations; yet have suffered from severe clearing in Colombia, triggering cascading effects such as desertification. By engaging scientists, society, and institutions in the establishment of platforms for monitoring biodiversity and ecosystem functioning, crucial knowledge gaps will be bridged, helping to find a path toward sustainable development. Science‐led but socially and economically anchored information on biodiversity will help to incorporate nature's contributions to people into the society's cultural values. Ultimately, these transformative actions will translate into the comprehensive management of TDF through a greater impact in decision making. Summary Thousands of permanent plots have been established across the tropics with the purpose of monitoring tree communities. Research outcomes from these platforms, however, have been mainly directed toward the academic community, and their contribution to society has been limited so far. Here, we show how generating robust data on biodiversity has supported decision making in Colombian tropical dry forests (TDF), where less than 8% of their original cover remains. As a first step to build a national dialogue around the critical status of this ecosystem, a national collaborative network on TDF research and monitoring was born in 2014, the Red de Investigación y Monitoreo del Bosque Seco Tropical en Colombia (Red BST‐Col). Our main goal is to generate scientifically sound information that feeds into the comprehensive management of this ecosystem. To do so, a set of biodiversity monitoring platforms has been established across the country, which have already served to answer socio‐ecological questions related with deforestation drivers, citizen science, or the valuation of ecosystem services. Overall, this research agenda has nurtured the four lines that underpin the Program for the comprehensive management of dry forests in Colombia (knowledge management, preservation, restoration, and sustainable use), formulated by the Humboldt Institute, the United Nations Development Programme, and the Ministry of Environment in 2019. Many challenges are ahead, however, for a complex territory where multiple social actors and productive sectors coexist. The ultimate goal is to integrate all the dimensions of biodiversity to achieve a synthetic understanding of the functioning of the most endangered ecosystem in Colombia, and its relationship with local communities' wellbeing. [ABSTRACT FROM AUTHOR]

ABSTRACT We present a synthesis (2006-2012) of plant community dynamics in an area (1 ha) of the largest remnant of Atlantic Rain Forest surrounded by São Paulo city. Plants with ≥ 2.5 cm dbh, including the climbers, were sampled in 10 transects (2 × 50 m), and the smaller (> 1 m height, < 2.5 cm dbh) in 10 subtransects (1 × 50 m). We sampled 901 individuals, 125 species (38 families), 83 classified as late-successional species, 12 threatened with extinction and 56 absent in the area management plan, some Endangered (EN) species. The climbers were the most dynamics, they had the largest decrease in basal area; and the larger (> 5.0 cm dbh) and shorter (< 2.5 cm dbh) trees had the highest mortality rates of the shrub-tree synusia. Late species regeneration was predominant. The studied forest showed progression towards more mature successional stages in the monitoring period.

This article evaluates the three-year vegetation dynamics of a species rich, protected steppe grassland on loess where no grazing occurred for decades at Bicske, Central Hungary. A detailed coenological survey of vascular vegetation was conducted in four permanent plots of 16 m2 each from 2018 to 2020. Raunkiaer’s life-forms, distribution range, and thousand-seed weight of species were evaluated. Shannon diversity and turnover rates for the species and the vegetation were also determined for each plot. In total, 108 vascular plant species were detected. The results indicate grassland stability when plant traits spectra were based on species presence data, but directional change if species cover values were used to weight trait categories. During the three years of the study, chamaephytes decreased and woody species increased their contribution for the Raunkiaer’s life-forms, while the cosmopolitan group has steadily lost its significance for distribution range types. Shannon diversity varied between 2.46 and 3.18 among plots (based on natural logarithm) and remained statistically unchanged through time. Average species turnover rates were 14.18% for 2018/19 and 17.52% for 2019/20, whereas corresponding values for vegetation turnover rates were 25.83% and 23.28%. Vegetation turnover rate was significantly higher than the species turnover rate.

Data from eight Permanent Plots of 1 ha (including a ll pla nts = 10 cm) a nd similar number of RAP Transects of 0.1 ha (including a ll pla nts = 2.5 cm) esta blished in prima ry tropica l humid forests, premontane (940 - 1 150 masl) and montane (2 078 - 2 770 masl) in the Chanchamayo valley (Junin / Peru) are here used to finding to which extent the minimum recorded diameter influences tree diversity as found in forest inventories. In each diameter class, both the species percents and Fisher's Alpha values are considered. Our results show that forest inventories including only large diameters, e.g. = 40 cm DBH, ca pture a low percent of the species (29.2% a nd 22.9% in premonta ne and montane forests, respectively); Fisher's Alpha values are coincident with these findings. [ABSTRACT FROM AUTHOR]

This paper presents the newly documented single specimen of the North Philippine temple pitviper (Tropidolaemus subannulatus), one of the venomous endemic snakes of the Philippines. The species has never been recorded in Cebu Island in the last two waves of survey in 1986 and 2016. The new record for Cebu Island on 13 Apr 2018 was a male juvenile T. subannulatus in a diverse forest over limestone in Mount Lantoy key biodiversity area (KBA), with an elevation of 648 m having geographic coordinates of 9.91395ºN and 123.51207ºE in Barangay Cansuje, Argao, Cebu, Philippines. The specimen was recorded in the permanent vegetation plot no. 1, established within the secondary natural forest, perching on the vines (Piper sp.). Some tree species found within the collection area were the following: Garcinia rubra, Ficus ampelas, Canarium asperum, Calophyllum blancoi, Gomphandra luzoniensis, and Goniothalamus almeri. The distance of occurrence from the ground is approximately 3 m. It seemed that the microhabitat characteristics of Mt. Lantoy KBA, particularly the forest over limestone in Barangay Cansuje, is favoring the survival of T. subannulatus. [ABSTRACT FROM AUTHOR]

Question: Infrequent events of extreme drought or extreme temperatures may considerably affect the structure and functioning of vegetation. Here we investigate how fluctuations in precipitation and temperature shape year‐to‐year dynamics and plant species composition in a dry grassland community, and how this variation affects plants with different life histories. Location: Dry grassland (Festucion valesiacae) in the Pavlov Hills, SE Czech Republic. Methods: Long‐term trends in vegetation change in the grassland studied were assessed by the ordination of plot records from vegetation surveys performed between 1930 and 2019. In addition, year‐to‐year changes in vegetation were studied in seven permanent plots of 16 m2 surveyed annually from 1993 to 2018. Variation in species composition and abundances was related to temperature and precipitation in the preceeding two springs, summers, autumns and winters using ordinations and mixed‐effect linear models. Results: There were no remarkable directional changes in the grassland community over the period 1930–2019. However, during the last 25 years, the community exhibited pronounced year‐to‐year fluctuations, which depended on weather conditions in the previous two years. Species with different life histories (e.g. perennials vs. annuals) and different ecology (e.g. ruderal vs. dry‐grassland species) responded differently to specific weather patterns. Perennials were sustained by wet summers, annuals benefitted from wet springs and autumns and moderately warm and wet winters, and covers of ruderals of mixed life histories increased after dry summers. Conclusions: Plant species composition in a Central European dry grassland shows remarkable year‐to‐year dynamics in response to weather patterns over the previous two years. These community changes are non‐directional and contribute to the stability of this grassland, which has not changed considerably over the past 90 years. However, increasing frequency of drought events because of ongoing climate change can result in a directional change with an expansion of ruderal species. [ABSTRACT FROM AUTHOR]

The extreme species richness of some temperate grasslands is a globally relevant yet understudied phenomenon. Until now, few records from thoroughly sampled, though not permanently fixed, vegetation plots were available. We therefore established a network of 40 permanent 4 × 4-m2 plots in species-rich grasslands of the White Carpathians (Czechia), Ukraine, Hungary and Romania. Thirty-one of them form the main dataset comprising plots from discrete forest-steppe grasslands (the Brachypodio-Molinietum association of the Cirsio-Brachypodion pinnati alliance), while nine of them forms the local dataset from a single locality in the White Carpathians, whose vegetation lacks most forest-steppe species and is transitional between the Bromion erecti and Arrhenatherion elatioris alliances (the Anthoxantho-Agrostietum and Anthyllido vulnerariae-Trifolietum montani associations). The permanent plots contain a nested subplot of 1 m2, except for five plots from Ukraine and Romania. Most plots harboured at least 80 vascular plant species per 16 m2, with the mean richness of 16-m2 plots was 95.3 species in the main dataset and 84 species in the local dataset. Mean richness of the 1-m2 subplots, presumably reflecting local environmental conditions and competitive relationships more than that of 16 m2 plots, did not vary between the two datasets, with a general mean of 57.6 species. Species counts of 16-m2 plots and 1-m2 subplots correlated, albeit only moderately, only in the main dataset. The presented datasets may be used for comparative analyses as well as for a future revisiting of the plots and may bring novel insights into the dynamics of extreme species richness. [ABSTRACT FROM AUTHOR]

The capability of plants to modify phenotypic characteristics through interactions with the environment can contribute to functional stability, particularly when this plasticity influences traits associated with survival, rendering it a pivotal mechanism for adaptation. Grime's CSR theory is employed to classify plants based on functional traits dictating competitive, stress, and ruderal tolerance strategies, as these traits serve as indicators of plant responses to environmental stimuli. This study examines the variation in plant functional traits (morphophysiological and phytochemical) within herbaceous communities across a chronosequence of natural regeneration after land-use alteration and abandonment. We investigate whether a correlation exists between regeneration duration and community-weighted mean values through principal component analysis and canonical correspondence analysis. Intraspecific variability of traits is assessed using one-way ANOVA and Tukey's post-hoc test at a significance level of 5% for mean comparisons. Generally, with progressing regeneration, intraspecific differences emerge, including elevated carbon:nitrogen ratio, phenolic compounds, and carbon assimilation, alongside reductions in leaf area, plant height, leaf succulence, individual biomass, and leaf nitrogen content. Consequently, pasture and initial regeneration communities harbor species with functional traits akin to ruderal species, whereas species inhabiting later stages exhibit traits associated with competitors. Analysis of intraspecific variation demonstrates that species occupying sites at different regeneration stages exhibit phenotypic plasticity. The findings underscore how alterations in environmental conditions during natural regeneration influence functional trait values, and underscore the utility of CSR theory for quantifying, comparing, and predicting community structure based on adaptive plant strategies. • Plant functional traits in herbaceous communities along a chronosequence of natural regeneration. • Increase Carbon:Nitrogen ratio in herbs in areas in an advanced stage of succession. • Increase production of phenolic compounds in herbaceous species in later stages. [ABSTRACT FROM AUTHOR]

The installation of research or permanent plots is a very common task in growth and forest yield research. At young ages, tree height is the most commonly measured variable, so the location of individuals is necessary when repeated measures are taken and if spatial analysis is required. Identifying the coordinates of individual trees and re-measuring the height of all trees is difficult and particularly costly (in time and money). The data used comes from three Pinus pinaster Ait. and three Pinus radiata D. Don plantations of 0.8 ha, with an age ranging between 2 and 5 years and mean heights between 1 and 5 m. Five individual tree detection (ITD) methods are evaluated, based on the Canopy Height Model (CHM), where the height of each tree is identified, and its crown is segmented. Three CHM resolutions are used for each method. All algorithms used for individual tree detection (ITD) tend to underestimate the number of trees. The best results are obtained with the R package, ForestTools and rLiDAR. The best CHM resolution for identifying trees was always 10 cm. We did not detect any differences in the relative error (RE) between Pinus pinaster and Pinus radiata. We found a pattern in the ITD depending on the height of the trees to be detected: the accuracy is lower when detecting trees less than 1 m high than when detecting larger trees (RE close to 12% versus 1% for taller trees). Regarding the estimation of tree height, we can conclude that the use of the CHM to estimate height tends to underestimate its value, while the use of the point cloud presents practically unbiased results. The stakeout of forestry research plots and the re-measurement of individual tree heights is an operation that can be performed by UAV-based LiDAR scanning sensors. The individual geolocation of each tree and the measurement of heights versus pole and/or hypsometer measurement is highly accurate and cost-effective, especially when tree height reaches 1–1.5 m.

The revegetation patterns after volcanic eruptions were monitored annually on Mount Usu, northern Japan, using over 25 years to detect successional changes. The vegetation was monitored by 2 × 5 m plots from 1984 and 2008 and by 5 × 5 m plots that were enlarged from the original plots from 1994 to 2008 due to increasing vegetation height. The thick tephra from these eruptions destroyed the former vegetation in 1977 and 1978. Diversity indexes were calculated, and nonmetric multidimensional scaling (NMDS) was conducted using the vegetation data with environmental factors. The cover of dominant species was higher in the large plots probably due to the vegetative expansion. Species richness and diversity continued to increase annually for 30 years after the eruptions. Well‐established plants were perennial forbs and trees and the species replacement occurred consistently. NMDS of small plot data suggested that elevation was related to the first axis, and year, litter volume and distance to the caldera rim were related to the second axis. Plot scores on the first axis suggested that deterministic factors, that is, elevation and its related factors, produced vegetation convergence but those on the second axis suggested that the vegetation change was in response to stochastic factors, such as litter accumulation and its related unmeasured factors, with year. The results indicated that the convergence or divergence was determined by the conflict between the net effects of deterministic and stochastic factors on vegetation development. [ABSTRACT FROM AUTHOR]

• Trait coordination supported the plant economics spectrum. • Traits from different organs had consistent effects on seedling mortality. • Root traits play a key role in determining seedling mortality. Plant traits from different organs are thought to be coordinated to achieve main vital functions. However, evidence on how the coordination of traits affect plant vital rates (e.g. mortality rates) is rare due to the poor representation of root traits, which play important roles in water and soil nutrients uptake. In this study, we collected plant traits from 13,733 seedlings of 57 species across 10-year monitoring in a subtropical forest in Southern China, asking whether traits from root and aboveground organs are coordinated, and whether they have consistent effects on seedling mortality (e.g. all fast resource-acquisitive traits reduce mortality). We performed phylogenetic principal component analysis (PPCA) to test trait coordination and used generalized linear mixed models (GLMMs) to examine trait-mortality relationships. We found that some of the root and aboveground traits were highly correlated. PPCA of traits separated species to the strategy of resource acquisition or conservation, supporting the plant economics spectrum. Traits from root, stem and leaf showed coordinated effects on seeding mortality, in which species with conservative traits tended to have lower mortality rates than species with acquisitive traits. Root traits, such as root nitrogen content, tissue density and specific root length significantly related to seedling mortality. We concluded that traits from different organs were coordinated describing an acquisitive-conservative continuum of strategies and have consistent effects on seedling mortality, providing the first evidence for the plant economics spectrum and for the root trait-mortality relationships in subtropical seedling communities. Our results emphasized that besides aboveground traits, key root traits significantly impact seedling mortality. Integrating root traits is necessary to gain further understanding in the relationships between plant performance and traits. [ABSTRACT FROM AUTHOR]

Methods to quantify plant‐insect interactions in tropical forests may miss many important arthropods and can be time consuming and uneven in capture efficiency. We describe the Amazonas‐trap, a new method that rapidly envelops the target plant for sampling arthropods. We evaluated the efficiency of the Amazonas‐trap by comparing it with two commonly used sampling methods to collect arthropods from plants: the beating tray and manual collection. Samples were collected in 10 permanent plots, in the Ducke forest reserve, Manaus (Amazonas, Brazil). In each plot we sampled 18 plant individuals of Protium sp. (Burseraceae): six by a beating tray, six by manual collection, and six using the Amazonas‐trap. All insects were identified to the family level and those belonging to the order Hymenoptera were identified to the species and morphospecies level. The new method sampled more insect families and more Hymenoptera species than tree beating and manual collection. Of the 75 total families collected, 20 were sampled exclusively by the Amazonas‐trap, seven were only collected with a beating tray, and seven were sampled exclusively with manual collecting. A similar pattern was found for abundance: Amazonas‐trap sampled more individuals, followed by the beating tray and manual collection. Small and winged arthropods were more abundant in Amazonas‐trap, explaining the highest richness of Hymenoptera and insect families sampled with this method. The new method sampled more spiders, wood‐fungi feeders, sap suckers, omnivorous, parasitoids, and insect predators than the other methods, but was equally effective in sampling leaf‐feeders and ants. Amazonas‐trap was more time consuming in the field, but for all diversity parameters evaluated, the new method showed better performance for collecting invertebrates on plants. [ABSTRACT FROM AUTHOR]

Successional change following disturbance is a fundamental ecological process that remains central to understanding patterns in plant ecology. Although succession has been studied for well over a century, understanding of the patterns and processes of change is still inadequate, partly because of the dearth of long‐term studies.Here, we use, as a model system, a volcanic disturbance that is widespread and of global relevance. We examine succession in old‐growth conifer forest understories following burial by tephra (aerially transported volcanic ejecta) in the 1980 eruption of Mount St. Helens. Using four sites with different initial conditions and amounts of disturbance (tephra burial), we sampled plant communities at years 1, 20, and 36 since the eruption using permanent plots representing two treatments: undisturbed tephra and control plots from which tephra was experimentally removed. By using this long‐term data, we were able to gauge change through time and differences between tephra‐disturbed and control plots.In tephra‐impacted plots, cover reached preeruption levels by year 36 except for bryophytes at three sites and shrubs at one site. Cover in control plots also increased significantly for all growth forms except bryophytes, remaining above that on tephra plots at the same site in most situations. Sites generally increased in species richness first, and then gradually increased in evenness and Shannon's diversity; after 36 years, differences between control and tephra‐impacted plots remained at only one site. Community composition was stable in one site and shifted gradually through time at the two other sites, and differences between plot types persisted at one site. Communities change over 36 years could relate to various endogenic and abiotic factors.Synthesis. These data suggest that, while recovery to the predisturbance status occurs in some cases, recovery is site‐specific. Understorey communities can be dynamic, even in old‐growth forests, and may still be responding to disturbance over three decades later. Long‐term experimental studies are key to understanding succession patterns and generalizations about the importance of initial conditions, disturbance intensity, and the complexity of interactions that determine vegetation change. Succession following disturbance may follow predictable trajectories or result in surprising outcomes. During 36 years following tephra deposition from the 1980 eruption of Mount St. Helens (USA), understories recovered in some but not other old‐growth forests, and plant communities demonstrated dynamic responses in both natural tephra and cleared plots. Long‐term measurements were key to understanding complex community change in response to volcanic disturbance. [ABSTRACT FROM AUTHOR]