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Mediterranean temporary ponds (MTPs) are seasonal wetland habitats usually flooded during the rainy season but drying out during the warmer months. Due to their biodiversity, uniqueness, and numerous threats, they are listed as a priority for conservation under the Habitats Directive. Despite all the efforts made so far, they are still in poor conservation status in the Mediterranean biogeographic region, making it urgent to define efficient conservation and restoration actions. In this work, we used two case studies to evaluate the conservation status improvement of MTPs located on the southwest coast of Portugal, following the implementation of different management techniques. Sampling was based on floristic surveys to assess plant richness and species frequency, namely of characteristic MTPs species. In the first case, we tested three management techniques (direct grazing, vegetation cutting, and biomass cut/removal, followed by topsoil plowing—simulating wild boar trampling and wallowing) in plots installed in three MTPs between 2017 and 2018. Plots subject to wild boar simulation disturbance showed higher species richness, higher frequency of characteristic species, and lower dominance of Agrostis stolonifera. In the second case, we upscaled this technique as an ecological restoration action by using it in 10 MTPs between 2018 and 2021. We observed a positive effect on the habitat's structure and conservation status, although the possible influence of recurrent drought periods in the last decade is discussed. This study provides insights into a rare wetland habitat based on lessons learned from hands‐on conservation actions, while also identifying new challenges and knowledge gaps. [ABSTRACT FROM AUTHOR]

There is increasing interestin broad‐scale analysis, modeling, and prediction of the distribution and composition of plant species assemblages under climatic, environmental, and biotic change, particularly for conservation purposes. We devised a method to reliably predict the impact of climate change on large assemblages of plant communities, while also considering competing biotic and environmental factors. To this purpose, we first used multilabel algorithms in order to convert the task of explaining a large assemblage of plant communities into a classification framework able to capture with high cross‐validated accuracy the pattern of species distributions under a composite set of biotic and abiotic factors. We applied our model to a large set of plant communities in the Swiss Alps. Our model explained presences and absences of 175 plant species in 608 plots with >87% cross‐validated accuracy, predicted decreases in α, β, and γ diversity by 2040 under both moderate and extreme climate scenarios, and identified likely advantaged and disadvantaged plant species under climate change. Multilabel variable selection revealed the overriding importance of topography, soils, and temperature extremes (rather than averages) in determining the distribution of plant species in the study area and their response to climate change. Our method addressed a number of challenging research problems, such as scaling to large numbers of species, considering species relationships and rarity, and addressing an overwhelming proportion of absences in presence–absence matrices. By handling hundreds to thousands of plants and plots simultaneously over large areas, our method can inform broad‐scale conservation of plant species under climate change because it allows species that require urgent conservation action (assisted migration, seed conservation, and ex situ conservation) to be detected and prioritized. Our method also increases the practicality of assisted colonization of plant species by helping to prevent ill‐advised introduction of plant species with limited future survival probability. Article impact statement: Broad‐scale analysis and modeling of plant assemblages under climatic‐biotic‐environmental cofiltering identifies species for early conservation. [ABSTRACT FROM AUTHOR]

The provision of valuable ecosystem services by tropical swamp forests (mainly carbon sequestration and storage in biomass and soil) explains their ecological importance. Current efforts toward the conservation of these ecosystems, however, face strong limitations as their spatial variation is largely unknown, particularly in regions where they occur over large areas. Here, we analyze the α-diversity (i.e., effective number of species or true diversity) and community structure variability of three tropical swamp forest communities distributed along an approximately 300 km long portion of the Usumacinta River Basin, southern Mexico. We sampled eighty-three 625-m2 plots to characterize the diversity and structural attributes of the woody plant communities. We recorded 2302 individuals belonging to 60 species and 25 families. Both α-diversity and structural attributes differed significantly among the three communities. The most inland community stood out for having the highest α-diversity for three true diversity values. Interestingly, the mangrove Rhizophora mangle L. was one of the dominant species, both in the swamp forest located closest to the coast and in the community farthest away from the sea. Basal area and density of individuals also had their maxima in the most inland swamp forest. The diversity and structural differences observed among the examined swamp forests seem to be related to contrasting environmental conditions, such as water salinity, distance to the coastline, and the hydrological dynamics of the Usumacinta River. We emphasize the urgency to conserve R. mangle populations in the swamp forest located farthest away from the coast due to its unusual habitat association, which appears to be a relictual condition.

Cerrado is considered one of the world's most threatened and floristically diverse tropical savannas. Distribution of the Cerrado flora comprises three countries: Bolivia, Brazil, and Paraguay; consequently, opportunities to conserve it require a transboundary effort. We aimed to (i) explore the relationship between a representative portion of Cerrado flora (8611 species), natural cover loss, and three country boundaries; and (ii) identify priority areas to expand protected areas at national and transboundary levels considering the different species conservation status, countries' governance, and natural cover loss. We modeled the distribution of Cerrado species for the three countries and overlapped species ranges with country boundaries to calculate species ranges shared between countries and the degree of endemicity. We identified national and transboundary priority regions to expand protected areas. We found that the areas with the highest plant richness are distributed in the central part of the Cerrado and Campos Rupestres Mountain Savanna ecoregions in Brazil (>8500 for the whole country). Bolivia ranked second in species richness (>4300), followed by Paraguay (>3700). The most anthropized areas in Brazil overlapped with regions predicted to foster the highest biodiversity. Conversely, such patterns were opposite in Bolivia and Paraguay, which harbored regions with high opportunities for Cerrado flora conservation. Transboundary prioritization suggested slightly higher species protection, including threatened and endemic species. Restoring some regions primarily in Brazil will be necessary to protect 30 % or 50 % of the study area. Together, the three countries can support more comprehensive conservation actions for the great diversity of the Cerrado flora. • Cerrado is one of the most threatened and floristically diverse tropical savannas. • Many plant species are distributed across Bolivia, Brazil, and Paraguay. • Most anthropized areas in Brazil are in regions with the highest plant richness. • Transboundary prioritization performed slightly better than national prioritization. • Three countries can support more comprehensive conservation actions for Cerrado. [ABSTRACT FROM AUTHOR]

Conservation planning relies heavily on representativeness patterns. In Chile, this has not been assessed at the species level. This study evaluates floristic representativeness in the National System of Protected Areas (SNASPE). Species rarefaction and non-parametric estimators were used to extrapolate total representativeness. Given that conservation planning in Chile is mainly based on protecting vegetation types, the effectiveness of using vegetation types as a surrogate of plant species was evaluated based on richness and complementarity. The study found available information for 42% of the 96 protected areas of continental Chile. According to this information the SNASPE protects at least 48% of the native vascular flora. The southern area protects the largest number of species, most of which are non-endemic natives. The largest number of endemic protected species was found in the central-northern area. The SNASPE in its full range is projected to protect 64% of the vascular flora of Chile. Richness and complementarity surrogacy analyses showed weak effectiveness of vegetation types as a surrogate of plant species, although complementarity performed slightly better than richness. Surrogacy effectiveness was lower for endemic species, probably due to their narrow distributions that are more easily missed when vegetation types are considered instead. [ABSTRACT FROM AUTHOR]

Many studies have investigated the possible impact of climate change on the distributions of plant species. In the present study, we test whether the concept of potential distribution is able to effectively predict the impact of climate warming on plant species. Using spatial simulation models, we related the actual (current species distribution), potential (modelled distribution assuming unlimited dispersal) and predicted (modelled distribution accounting for wind-limited seed dispersal) distributions of two plant species under several warming scenarios in the Sagarmatha National Park (Nepal). We found that the two predicted distributions were, respectively, seven and nine times smaller than the potential ones. Under a +3 °C scenario, both species would likely lose their actual and predicted distributions, while their potential distributions would remain partially safe. Our results emphasize that the predicted distributions of plant species may diverge to a great extent from their potential distributions, particularly in mountain areas, and predictions of species preservation in the face of climate warming based on the potential distributions of plant species are at risk of producing overoptimistic projections. We conclude that the concept of potential distribution is likely to lead to limited or inefficacious conservation of plant species due to its excessively optimistic projections of species preservation. More robust strategies should utilize concepts such as “optimal reintroduction”, which maximizes the benefit–cost ratio of conservation activities by limiting reintroduction efforts to suitable areas that could not otherwise be reached by a species; moreover, such strategies maximize the probability of species establishment by excluding areas that will be endangered under future climate scenarios. [ABSTRACT FROM AUTHOR]

Leatherleaf Chamaedaphne calyculata (L) Moench is a relict, rare and endangered species in Poland. There are no reports on the micropropagation of Chamaedaphne calyculata in the literature. Therefore, the aim of this study was to propose a propagation protocol for leatherleaf via indirect organogenesis using leaves and stems (internodal segments) derived from mature plants growing in a natural stand and from plants grown in vitro as explants. The medium developed by Anthony et al. (2004) with 100%, 50% and 25% salt concentrations, supplemented with IAA (5 and 10µM) and TDZ (5 and 10µM), was used for callus development and the induction of adventitious shoots. The media developed by Anthony et al. (2004) and Anderson (1980), both containing 10µM TDZ and 5µM IAA or 2.28µM zeatin, were used for adventitious shoot elongation. Secondary explants proved to be the most effective starting material for callus induction, the regeneration and elongation of adventitious shoots. The most supportive medium for callus induction and growth and the induction of adventitious shoots was the full medium proposed by Anthony et al. (2004) containing 5µM IAA and 10µM TDZ. Anderson's (1980) medium containing 2.28µM zeatin delivered optimal results in the elongation of adventitious shoots of Ch. calyculata. Roots were cultivated on Anderson's (1980) phytohormone-free medium. Approximately 65% of the plantlets survived after transfer to the sphagnum-peat and perlite mixture (3:1). The plants grew normally without any signs of morphological variation. This study makes the first ever attempt to propose an effective micropropagation protocol for Ch. calyculata. [ABSTRACT FROM AUTHOR]

Remaining populations of plant species in fragmented landscapes are threatened by declining habitat quality and reduced genetic diversity, but the interactions of these major factors are rarely studied together for species conservation. In this study, the interactions between population size, habitat quality, genetic diversity and fitness were investigated in 22 populations of the clonal herb Cirsium dissectum throughout the British Isles. Regression analysis was used to identify significant factors, and a structural equation model was developed to illustrate and integrate these interactions. It was found that smaller populations (measured as the total number of plants) had lower genetic diversity (proportion of polymorphic loci), and that reduced genetic diversity (allelic richness) had a negative impact on the survival of seedlings grown under standard conditions. Habitat quality also had a large effect on C. dissectum. Unmanaged sites with tall vegetation, no bare soil and higher nutrient levels had smaller populations of C. dissectum, but flowering was promoted. Flowering was suppressed in heavily grazed sites with short vegetation. Higher levels of bare soil and phosphorus both had a positive relationship with genetic diversity, but probably for distinctly different reasons: bare soil provides safe sites for establishment, whilst phosphorus may promote flowering and improve seed germination. In order to conserve C. dissectum, management needs to maintain site heterogeneity so that C. dissectum can flower and establishment gaps are still available for seedlings; when either component is reduced, negative feedbacks through reduced genetic diversity and individual fitness can be expected. This study therefore highlights the importance of considering both conservation genetics and habitat quality in the conservation of plant species. [ABSTRACT FROM AUTHOR]

1. During the last century, many plant species typical of heathland and nutrient-poor acidic grasslands have become rare whereas others have remained common. Habitat restoration often fails to enhance the rare species, which may in part be caused by the failure to restore the biogeochemical conditions suited to these species. Many soil variables have been shown to affect plant fitness but it is unknown what their relative importance is and whether any biogeochemical variable acts as a key factor constraining the persistence of rare heathland species. 2. We compiled a data set consisting of 300 vegetation samples and the associated soil chemical properties from a range of studies carried out across the Netherlands. We asked whether growth sites of rare and common species typical of heathland and acidic grasslands differed in their biogeochemical properties, and whether growth sites of rare species displayed less variation in soil biogeochemical variables (e.g. had narrower ecological amplitude). 3. Regardless of rarity, the species’ growth sites were most accurately described by a curvilinear relationship between pH and Al/Ca ratios. Other soil characteristics did not vary systematically with changing acidity of the soil or the patterns were less pronounced. Acidification will therefore most rapidly and predictably result in an increase in Al/Ca ratio whereas this is not necessarily the case for the other soil variables affecting plant fitness. 4. The soil ammonium (NH4) concentration and ammonium/nitrate (NH4/NO3) ratio were 3·5 and 3 times higher, respectively, in growth sites of common species compared with those of rare species. No other measured variable differed significantly between rare and common plant species. 5. On average rare species had a significantly narrower ecological amplitude than common species for soil biogeochemical parameters. 6. Synthesis and applications. A greater sensitivity to high NH4 concentrations in combination with a narrower ecological tolerance zone for a range of soil biogeochemical factors may explain the demise of rare species adapted to nutrient-poor acidic habitats in recent decades. Conservation management should aim to restore low NH4 concentrations and NH4/NO3 ratios. Experimental studies indicate that the most effective way to do this is through removal of the topsoil in combination with liming. [ABSTRACT FROM AUTHOR]

The provision of valuable ecosystem services by tropical swamp forests (mainly carbon sequestration and storage in biomass and soil) explains their ecological importance. Current efforts toward the conservation of these ecosystems, however, face strong limitations as their spatial variation is largely unknown, particularly in regions where they occur over large areas. Here, we analyze the α-diversity (i.e., effective number of species or true diversity) and community structure variability of three tropical swamp forest communities distributed along an approximately 300 km long portion of the Usumacinta River Basin, southern Mexico. We sampled eighty-three 625-m2 plots to characterize the diversity and structural attributes of the woody plant communities. We recorded 2302 individuals belonging to 60 species and 25 families. Both α-diversity and structural attributes differed significantly among the three communities. The most inland community stood out for having the highest α-diversity for three true diversity values. Interestingly, the mangrove Rhizophora mangle L. was one of the dominant species, both in the swamp forest located closest to the coast and in the community farthest away from the sea. Basal area and density of individuals also had their maxima in the most inland swamp forest. The diversity and structural differences observed among the examined swamp forests seem to be related to contrasting environmental conditions, such as water salinity, distance to the coastline, and the hydrological dynamics of the Usumacinta River. We emphasize the urgency to conserve R. mangle populations in the swamp forest located farthest away from the coast due to its unusual habitat association, which appears to be a relictual condition. [ABSTRACT FROM AUTHOR]

There is increasing interest in broad-scale analysis, modeling, and prediction of the distribution and composition of plant species assemblages under climatic, environmental, and biotic filtering, particularly for conservation purposes. We devised a method (broad-scale analysis & modeling of plant assemblages under climatic-biotic-environmental co-filtering, BAM-PACC) for reliably predicting the impact of climate change on arbitrarily large assemblages of plant communities, while also considering competing biotic and abiotic factors. When applied to a large set of plant communities in the Swiss Alps, BAM-PACC explained presences/absences of 175 plant species in 608 plots with >87% cross-validated accuracy, predicted decreases in α, β, and γ diversity by 2040 under both moderate and extreme climate scenarios, and identified plant species likely to be favored/disfavored by climate change. BAM-PACC also revealed the importance of topography and soil in determining the distribution of plant species and their response to climate change, and showed the overriding importance of temperature extremes rather than averages. BAM-PACC was able to address a number of challenging research problems, such as scaling to large numbers of species, exploiting species relationships, dealing with species rarity, and overwhelming proportion of absences in the presence/absence matrix. By handling hundreds/thousands of plants and plots simultaneously over large areas, BAM-PACC can help broad-scale conservation of plant species under climate change, as it allows species that require urgent conservation planning and policies (assisted migration, seed conservation, ex-situ conservation) to be detected and prioritized. BAM-PACC can also increase the practicality of assisted colonization of plant species, by helping to prevent ill-advised introduction of plant species with limited future survival probability in a certain area. This article is protected by copyright. All rights reserved., (This article is protected by copyright. All rights reserved.)