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ABSTRACT Aim Location Methods Results Main Conclusions Seed dispersal plays a key role in shaping the distribution and genetic complexity of seagrass populations and affects their resilience capacity under disturbance. The endemic seagrass Posidonia oceanica is a key component of Mediterranean coastal ecosystems, but knowledge about movement ecology in this species is limited, especially regarding seed movement pathways and dispersal potential.Western coast of Sicily (central Mediterranean).Beach‐cast fruits of the Mediterranean seagrass P. oceanica were collected from nine localities along the Western coast of Sicily, along with adult shoots from eight putative donor meadows. We determined pair‐wise genetic differentiation between established meadows and seed cohorts. Genetic assignment tests were used to infer the most likely meadow of origin of individual seeds and were complemented with forward and backward Lagrangian simulations of dispersal.A significant genetic differentiation was found between seed pools and the most‐likely meadow of origin. The genetic assignment confirmed that seeds from the same cohort originated from multiple meadows and emphasised the presence of long‐distance‐dispersal (LDD) events (up to hundreds of km). Genetic connectivity appeared to be greater than that predicted by oceanographic simulations, which may reflect the longer temporal scales on which gene flow is shaped, in contrast to contemporary dispersal patterns. Lagrangian simulations highlighted that fruits were physically capable of dispersing beyond the study area and that the north Tunisian coast could be a key source of propagules for the populations studied.Our study represents a significant step forward in the understanding of P. oceanica movement ecology and could guide meadows' conservation and restoration actions. Our findings are significant in a broader context outside of the research area and could be the basis of similar studies in other regions, especially considering the increasing number of fruiting events recorded across the Mediterranean likely associated with ocean warming. [ABSTRACT FROM AUTHOR]

Nematodes typically comprise the most abundant phylum in meiofaunal communities. We aim to characterize the specific ecological conditions that influence Nematoda communities in Posidonia oceanica grasslands focusing on three habitats: leaves, matte, and unvegetated adjacent sediment. We hypothesized that the constant flux of nutrients under the canopy would result in a higher concentration of metazoans compared to the unvegetated sediment outside; however, the hypothesis was not confirmed by the obtained results. The habitat heterogeneity played an important role in shaping the community, yielding a greater richness in the matte. The resource specificity of the leaves (microepiphytes) was also expected to shape the community by favoring nematodes capable of exploiting this resource (epistratum feeders with scraping-like structures), such as the family Chromadoridae that dominated this habitat. In addition, the high light exposure of the leaves explains the higher concentration of ocellated nematodes in this habitat. Organic carbon and nitrogen contents had an impact on the Nematoda community composition, meanwhile average grain size only affected the abundance of nematodes with elongated/filiform tails. [ABSTRACT FROM AUTHOR]

On the basis of the data received from the research experiment conducted with bird's-foot-trefoil, red clover and sainfoin, fertilized with humate fertilizers on the territory of the experimental field of Research Institute of Mountain Stockbreeding and Agriculture -- Troyan during the period 2013-2015, correlation dependencies and regression equations were constructed. A positive correlation dependence was established between: the phosphorus content and the height of fertilizer meadows with legumes (r = 0.90); the content of nitrogen-free extractable substances and the relative share of the stems (r = 0.86); and the crude protein and the percentage share of leaves (r = 0.80). This proves the positive effect of fertilizing with boron and molybdenum humate on growth and development of legumes, the accumulation of nutrients in the forage. The regression equations derived prove the possibility of predicting the crude protein content from the share of leaves in the grass stand (R² = 0.64), the phosphorus content from the height of the stems (R² = 0.81) and of the nitrogen-free extractable substances from the relative share of the stems (R² = 0.75), in the grass stands. Two-factor analysis of variance showed the high impact of the conditions of the year (η = 68.69) on the dry matter yield. [ABSTRACT FROM AUTHOR]

Understanding animals' selection of microhabitats is important in both ecology and biodiversity conservation. However, there is no generally accepted methodology for the characterization of microhabitats, especially for vegetation structure. We studied microhabitat selection of three Vipera snakes by comparing grassland vegetation structure between viper occurrence points and random points in three grassland ecosystems: V. graeca in mountain meadows of Albania, V. renardi in loess steppes of Ukraine and V. ursinii in sand grasslands in Hungary. We quantified vegetation structure in an objective manner by automated processing of images taken of the vegetation against a vegetation profile board under standardized conditions. We developed an R script for automatic calculation of four vegetation structure variables derived from raster data obtained in the images: leaf area (LA), height of closed vegetation (HCV), maximum height of vegetation (MHV) and foliage height diversity (FHD). Generalized linear mixed models revealed that snake occurrence was positively related to HCV in V. graeca, to LA in V. renardi and to LA and MHV in V. ursinii, and negatively to HCV in V. ursinii. Our results demonstrate that vegetation structure variables derived from automated image processing significantly relate to viper microhabitat selection. Our method minimizes the risk of subjectivity in measuring vegetation structure, enables the aggregation of adjacent pixel data and is suitable for comparison of or extrapolation across different vegetation types or ecosystems. [ABSTRACT FROM AUTHOR]

Few restoration studies have quantified the recovery of the donor meadow. We evaluated the recovery of a monospecific donor meadow of Halodule wrightii, the second most commonly used transplanting species, and assessed the possible effect of 24 plots of 1 m2 placed in an approximately 3,400 m2 large monospecific meadow with a mean cover of 45%, foliar shoot density of 1,280 shoots/m2, and 16 cm canopy height. Extraction densities were 9, 25, 64, and 121 small‐sized extraction cores (4.5 cm diameter, 20 cm depth), with control and procedural control without extractions (N = 4 per treatment). After 6 months, even the plots with the highest extraction densities recovered, as indicated by the shoot number in the extraction areas and seagrass cover in the plots approaching the levels in the controls. The recovery occurred under the environmental conditions: light availability (22,000 ± 51 lx), relatively stable sediments (0.8–1.16 cm) with a fine sandy composition (mean grain diameter, D50: 0.5 ± 0.22 mm), and low organic matter (0.22 ± 0.012%). The recolonization rate was 1–3 shoots per month in the 4.5 cm diameter extraction areas, independent of the extraction level. Thus, approximately 20% of the H. wrightii meadow (corresponding with 121 cores/m2) could be extracted in our study area. This high extraction intensity can be attributed to the adequate selection of donor species, meadow, and size of the planting unit. [ABSTRACT FROM AUTHOR]

The genetic traits of seagrass populations are a crucial aspect of their ecology and evolution, influencing their adaptability and resilience. Here, we studied the genetic diversity, population structure, and connectivity of eighteen Posidonia oceanica meadows extending in the Eastern Mediterranean Sea (Aegean, Ionian and Cretan Seas, Greece), combining twelve microsatellite markers and Lagrangian particle drift modelling. Our findings revealed a strong genetic differentiation between the Ionian Sea and the Aegean and Cretan Seas, suggesting limited genetic exchange between these two groups. High gene flow was observed within the meadows of the Aegean and Cretan Seas, indicating a well-connected group of populations. Notably, populations of the North Aegean Sea displayed the lowest genetic diversity and the highest clonality compared to the rest of the populations. The lack of substantial oceanographic connectivity between Ionian and Aegean/Cretan Sea populations supported their genetic differentiation. However, the Lagrangian simulations did not fully support gene flow patterns in the Aegean Sea, suggesting that in addition to contemporary processes, historical events may have contributed to the formation of the observed genetic pattern. The genetic information provided here can be incorporated into management strategies aimed at identifying suitable areas as management units in conservation efforts and determining meadows that may serve as donor sites in transplantation initiatives. [ABSTRACT FROM AUTHOR]

Many fire‐prone forests are experiencing wildfires that burn outside the historical range of variation in extent and severity. These fires impact pollinators and the ecosystem services they provide, but how the effects of fire are mediated by burn severity in different habitats is not well understood. We used generalized linear mixed models in a Bayesian framework to model the abundance of pollinators as a function of burn severity, habitat, and floral resources in post‐fire, mid‐elevation, conifer forest, and meadow in the Sierra Nevada, California. Although most species‐level effects were not significant, we found highly consistent negative impacts of burn severity in meadows where pollinators were most abundant, with only hummingbirds and some butterfly families responding positively to burn severity in meadows. Moderate‐severity fire tended to increase the abundance of most pollinator taxa in upland forest habitat, indicating that even in large fires that burn primarily at high‐ and moderate‐severity patches may be associated with improved habitat conditions for pollinator species in upland forest. Nearly all pollinator taxa responded positively to floral richness but not necessarily to floral abundance. Given that much of the Sierra Nevada is predicted to burn at high severity, limiting high‐severity effects in meadow and upland habitats may help conserve pollinator communities whereas low‐ to moderate‐severity fire may be needed in both systems. [ABSTRACT FROM AUTHOR]

Many fire‐prone forests are experiencing wildfires that burn outside the historical range of variation in extent and severity. These fires impact pollinators and the ecosystem services they provide, but how the effects of fire are mediated by burn severity in different habitats is not well understood. We used generalized linear mixed models in a Bayesian framework to model the abundance of pollinators as a function of burn severity, habitat, and floral resources in post‐fire, mid‐elevation, conifer forest, and meadow in the Sierra Nevada, California. Although most species‐level effects were not significant, we found highly consistent negative impacts of burn severity in meadows where pollinators were most abundant, with only hummingbirds and some butterfly families responding positively to burn severity in meadows. Moderate‐severity fire tended to increase the abundance of most pollinator taxa in upland forest habitat, indicating that even in large fires that burn primarily at high‐ and moderate‐severity patches may be associated with improved habitat conditions for pollinator species in upland forest. Nearly all pollinator taxa responded positively to floral richness but not necessarily to floral abundance. Given that much of the Sierra Nevada is predicted to burn at high severity, limiting high‐severity effects in meadow and upland habitats may help conserve pollinator communities whereas low‐ to moderate‐severity fire may be needed in both systems. [ABSTRACT FROM AUTHOR]

• Leaving 10% of the meadow uncut as a refuge is positive for the invertebrate community. • We experimentally investigated the effect on the vegetation. • Within-year rotational uncut refuges do not impact negatively the vegetationa s long as the refuges change location at each mowing event. • The refuge should not be placed at the same location for three consecutive years. Invertebrates inhabiting grasslands benefit from uncut grass refuges, yet effects on the plant community have not been properly quantified. We experimentally investigated the effects on the vegetation of two different types of refuges. While both consisted in not mowing 10–20% of a meadow area, they differed in their rotation frequency: (1) in within-year rotational refuges (WYRR), the location of the refuge within a meadow was changed at each mowing operation, usually twice a year; (2) in between-years rotational refuges (BYRR), the refuge changed location only between years. A third mowing regime without any refuge was included as control (C) for comparison. The study was conducted in thirty extensively managed meadows across the Swiss lowlands. The vegetation was sampled at two 1-m2 plots within each of the four strata defined by a stratified random design that accounted for the spatial location of the uncut refuge over the years. There were no overall significant negative effects of WYRR on plant species richness and composition at the meadow scale, although a small negative effect was detected locally (i.e. at the refuge scale) where a WYRR had been implemented more than once in the preceding three years. Leaving BYRR negatively impacted plant species richness (-11%), even reducing the number of indicator plant species by 22% (from 4.5 to 3.5 per 2 m2), regardless of when and where refuges were left uncut. A beta-diversity analysis revealed no difference at community level between the two refuge types and control meadows. Previous studies had evidenced positive effects of uncut refuges on herbivore and pollinator communities, while this study shows that the plant community is not affected as long as the location of the refuge is changed at each mowing operation. We thus recommend this measure for promoting biodiversity in extensively managed grasslands. [ABSTRACT FROM AUTHOR]

Seagrasses harbour different and rich epiphytic bacterial communities. These microbes may establish intimate and symbiotic relationships with the seagrass plants and change according to host species, environmental conditions, and/or ecophysiological status of their seagrass host. Although Posidonia oceanica is one of the most studied seagrasses in the world, and bacteria associated with seagrasses have been studied for over a decade, P. oceanica's microbiome remains hitherto little explored. Here, we applied 16S rRNA amplicon sequencing to explore the microbiome associated with the leaves of P. oceanica growing in two geomorphologically different meadows (e.g. depth, substrate, and turbidity) within the Limassol Bay (Cyprus). The morphometric (leaf area, meadow density) and biochemical (pigments, total phenols) descriptors highlighted the healthy conditions of both meadows. The leaf-associated bacterial communities showed similar structure and composition in the two sites; core microbiota members were dominated by bacteria belonging to the Thalassospiraceae, Microtrichaceae, Enterobacteriaceae, Saprospiraceae, and Hyphomonadaceae families. This analogy, even under different geomorphological conditions, suggest that in the absence of disturbances, P. oceanica maintains characteristic-associated bacterial communities. This study provides a baseline for the knowledge of the P. oceanica microbiome and further supports its use as a putative seagrass descriptor. [ABSTRACT FROM AUTHOR]

Understanding sexual reproduction and recruitment in seagrasses is crucial to their conservation and restoration. Flowering, seed production, seed recruitment, and seedling establishment data for the seagrass Posidonia australis was collected annually between 2013 and 2018 in meadows at six locations around Rottnest Island, Western Australia. Variable annual rates of flowering and seed production were observed among meadows between northern and southern sides of the island and among years. Meadows on the northern shore consistently flowered more intensely and produced more seeds across the years of the survey. Inter‐site variation in clonal diversity and size of clones, seed production, wind and surface currents during pollen and seed release, and the large, but variable, impact of seed predation are likely the principal drivers of successful recruitment into established meadows and in colonizing unvegetated sands. The prolific but variable annual reproductive investment increases the probability of low levels of continuous recruitment from seed in this seagrass, despite high rates of abiotic and biotic disturbance at seedling, shoot, and patch scales. This strategy also imparts a level of ecological resilience to this long‐lived and persistent species. [ABSTRACT FROM AUTHOR]

Fuentes-Agueda, S.A.; Gallegos, M.E.; Mandujano, M.C., and Golubov, J., 2023. Contrasting growth and establishment of Thalassia testudinum along a cover gradient in the Gulf of Mexico. Journal of Coastal Research, 39(4), 653–662. Charlotte (North Carolina), ISSN 0749-0208. Seagrasses are important for coastal ecosystem health and have significant economic benefits; however, they are undergoing important negative changes worldwide. The seagrass Thalassia testudinum comprises one of the main elements in submerged aquatic vegetation (SAV) habitats, and it grows in monospecific and mixed meadows along the continental shelf of the Gulf of Mexico. In this study, T. testudinum monospecific and mixed meadows were monitored over a 2 year period to identify the abiotic and biotic conditions that may correlate with population parameters through the plastochron index (PI). Plants found in monospecific meadows had larger rhizomes and more flowers in comparison to those in mixed meadows, while the latter produced more leaves and larger shoots. The annual rate of change in biomass (Br) of T. testudinum in the monospecific meadow was 1.15 ± 0.03, which was slightly higher than that in the mixed meadow, with a value of 1.12 ± 0.03. T. testudinum in monospecific meadows tended to exhibit increased sexual reproduction, while vegetative growth and clonal reproduction were more common in mixed meadows. The results highlight that T. testudinum life-history strategies and establishment are affected by both biotic and abiotic factors like depth, temperature, and water nutrients. [ABSTRACT FROM AUTHOR]

Meadows on organic soils perform an essential role as a source of fodder and biomass for energy purposes. In the case of intensive meadows, it is crucial to use grass mixtures that enable obtaining high yields of good quality; however, on organic soils, the grass species composition changes dynamically. We carried out the full cultivation (ploughing) for grassland restoration. The floristic composition of meadow sward in the first year of full use (2013) was similar to the composition of mixtures used for sowing (2012) individual plots. Festuca arundinacea and Phleum pratense showed greater resistance to low temperatures in winter and excess water in spring compared to Lolium perenne. In comparison, we obtained the highest yield (fresh and dry mass) from mixtures with Festuca arundinacea and Lolium perenne. We obtained the best quality forage from the first swath and the object with the highest share of Lolium perenne. For grassland restoration in the analysed habitat, it is reasonable to use grass mixtures with varied compositions, in which the share of Lolium perenne is between 25–50%. [ABSTRACT FROM AUTHOR]

The Posidonia oceanica meadows represent a fundamental biological indicator for the assessment of the marine ecosystem's state of health. They also play an essential role in the conservation of coastal morphology. The composition, extent, and structure of the meadows are conditioned by the biological characteristics of the plant itself and by the environmental setting, considering the type and nature of the substrate, the geomorphology of the seabed, the hydrodynamics, the depth, the light availability, the sedimentation speed, etc. In this work, we present a methodology for the effective monitoring and mapping of the Posidonia oceanica meadows by means of underwater photogrammetry. To reduce the effect of environmental factors on the underwater images (e.g., the bluish or greenish effects), the workflow is enhanced through the application of two different algorithms. The 3D point cloud obtained using the restored images allowed for a better categorization of a wider area than the one made using the original image elaboration. Therefore, this work aims at presenting a photogrammetric approach for the rapid and reliable characterization of the seabed, with particular reference to the Posidonia coverage. [ABSTRACT FROM AUTHOR]

Ecological systems can be regarded as natural capital that yields ecosystem services vital for human well-being. The provision of these services strictly depends on the protection of natural capital stocks generating them, highlighting the need for conservation and monitoring actions led by proper assessment methodologies. Among the available methods, the Environmental Accounting Model based on the emergy approach is rapidly gaining popularity in ecological applications. We used such method to assess the natural capital value of Posidonia oceanica meadows, widely recognized the most important ecosystems in the Mediterranean basin, at Italian national spatial scale. The natural capital value of P. oceanica was further weighed by the estimates provided by a Habitat Suitability Model. We observed that the estimated level of habitat suitability played an important role as modifier of the average biophysical value of P. oceanica. Our approach allowed to identify the meadows having the highest stability and over space and time, which we defined as the most valuable in biophysical terms, thus with highest natural capital value. The spatially explicit estimates we provided could support managers and policy-makers to ensure the long-term provision of ecosystem services generated by P. oceanica , enhancing ecosystem management and maritime spatial planning. [ABSTRACT FROM AUTHOR]

Aims: Once widely used across Europe, grazing of hay meadows is now a rare agricultural practice that is mainly applied in rural regions with maintained traditional agriculture. In this review, we examine the knowledge on grazing hay meadows in the Carpathian Mountains, including its historical distribution, implementation and timing, potential impacts on grassland productivity and biodiversity, and implications for grassland conservation and restoration. Location: The Carpathian Mountains (43.8–50.1°N, 16.9–27.1°E). Methods: We conducted a literature review including biological, ecological, agricultural, ethnological, and historical sources. Results and Conclusions: In each of the seven farming systems that existed in parallel in the Carpathian Mountains before agricultural intensification, grazing of hay meadows was applied regularly. Spring, autumn, and occasionally summer grazing, along with corralling and manuring of hay meadows, were integral parts of these systems, adapted to the seasonal movement of dairy farms across various agroecosystems. The data reviewed provide insight into the role of animals in hay meadow management, as well as how the breakdown of these historical farming systems is impacting local biodiversity, the economy, and the community. According to the literature sources, grazing hay meadows has numerous positive impacts on grassland biodiversity, including suppressing fast‐growing competitors, reducing the accumulation of litter, increasing the availability of germination gaps, dispersing seeds through zoochory, supporting ground‐nesting birds through later mowing, and promoting the regeneration of plants from seeds. From this perspective, the combination of mowing and grazing can be considered a promising tool in current grassland conservation and restoration efforts. [ABSTRACT FROM AUTHOR]

Historical and contemporary processes drive spatial patterns of genetic diversity. These include climate‐driven range shifts and gene flow mediated by biogeographical influences on dispersal. Assessments that integrate these drivers are uncommon, but critical for testing biogeographic hypotheses. Here, we characterize intraspecific genetic diversity and spatial structure across the entire distribution of a temperate seagrass to test marine biogeographic concepts for southern Australia. Predictive modeling was used to contrast the current Posidonia australis distribution to its historical distribution during the Last Glacial Maximum (LGM). Spatial genetic structure was estimated for 44 sampled meadows from across the geographical range of the species using nine microsatellite loci. Historical and contemporary distributions were similar, with the exception of the Bass Strait. Genetic clustering was consistent with the three currently recognized biogeographic provinces and largely consistent with the finer‐scale IMCRA bioregions. Discrepancies were found within the Flindersian province and southwest IMCRA bioregion, while two regions of admixture coincided with transitional IMCRA bioregions. Clonal diversity was highly variable but positively associated with latitude. Genetic differentiation among meadows was significantly associated with oceanographic distance. Our approach suggests how shared seascape drivers have influenced the capacity of P. australis to effectively track sea level changes associated with natural climate cycles over millennia, and in particular, the recolonization of meadows across the Continental Shelf following the LGM. Genetic structure associated with IMCRA bioregions reflects the presence of stable biogeographic barriers, such as oceanic upwellings. This study highlights the importance of biogeography to infer the role of historical drivers in shaping extant diversity and structure. [ABSTRACT FROM AUTHOR]

Oregon semaphoregrass (Pleuropogon oregonus Chase [Poaceae]) is a rare grass that occurs in only a handful of locations in eastern Oregon montane wet meadows, primarily on private lands. Propagation and outplanting methods have been developed over the past few decades to expand the geographic extent and to increase the number of plants by introductions in protected areas. The species rapidly increases through rhizomatous growth in a range of environmental conditions, provided sufficient moisture and nutrients are present, but is susceptible to some pests and pathogens. Over 2 decades, introductions with vegetative material have survived and increased in a mid-elevation meadow on Burns Paiute Tribal lands, a site relatively far from natural populations. Introductions in other areas have largely failed, however, likely because of unsuitable site environmental characteristics. Lessons learned from the successful propagation and outplanting program on Burns Paiute Tribal lands may be useful in future introductions, provided necessary site environmental attributes are identified. [ABSTRACT FROM AUTHOR]

In the Mediterranean, the fleshy, mat-forming red alga Phyllophora crispa creates high-biodiversity habitats that influence light availability, water movement, and temperature. However, knowledge about its influence on other key environmental parameters, such as oxygen availability, chlorophyll, and turbidity, is missing. Therefore, we conducted an in situ study in the Western Mediterranean Sea using multiparameter probes that were placed multiple times on algal P. crispa mats, in adjacent Posidonia oceanica seagrass meadows, and on bare hard bottoms. We acquired a total of 17 full diel measurements for dissolved oxygen (DO), chlorophyll, and turbidity in September and October 2019. Results showed that P. crispa mats influence the investigated parameters differently when compared to P. oceanica meadows and that a monthly effect was observed. In September, general DO patterns measured for P. crispa mats and P. oceanica meadows follow the daily cycle depending on light availability, with the measured DO being lower in the P. oceanica meadows compared to the P. crispa mats and the hard-bottom habitats. In October, however, no significant difference in DO concentrations was observed between P. crispa mats and P. oceanica meadows. Results of this study corroborate that P. crispa mats can be viewed as an ecosystem engineering species, influencing environmental parameters and, hence, providing a habitat for outstanding associated biodiversity. [ABSTRACT FROM AUTHOR]

Meadows of the seagrass Posidonia oceanica inhabit most infralittoral bottoms of the Mediterranean Sea and are considered one of the main climax stages of the infralittoral environment. This seagrass has its western distributional limit along the coast of the Alboran Sea. Taking into account the decline of P. oceanica meadows and the global scenario of ocean warming, it becomes essential to know the structure, temporal dynamics, sexual reproduction and conservation status of this seagrass, across its geographical distribution, including the distribution boundaries where the meadows withstand limiting environmental conditions. In the present work, we studied the structure, phenology and flowering events of four P. oceanica meadows located in the northwestern Alboran Sea (close to the Strait of Gibraltar). Results indicate a decreasing trend of patch size, bathymetric range and number of leaves per shoot towards the Strait (and the Atlantic Ocean), as well as an increasing trend of shoot density and leaf height. Phenological parameters of the northwestern Alboran Sea P. oceanica meadows presented temporal dynamics similar to meadows from other locations within the biogeographical distribution of this seagrass, with similar or even less annual variability in the former. Although most of the studied P. oceanica meadows seem to present a good health status (BiPo index ~0.6) with high shoot densities and some flowering events, some of them showed evidence of regression. [ABSTRACT FROM AUTHOR]

In coastal lagoons, marine benthic macrophyte meadows can be an important element in the resistance to eutrophication of the ecosystem, as they can function as temporary nitrogen sinks, limiting the availability of this nutrient for opportunistic organisms. The role of nitrogen sinks for two dominant macrophyte species of Mediterranean coastal lagoons, the seagrass Cymodocea nodosa and the seaweed Caulerpa prolifera, was analysed by two different approaches: (i) studying nitrate (NO3-) and ammonium (NH4+) uptake kinetics of aboveground tissues in a laboratory and (ii) estimating nitrogen stocks and demands of meadows under natural conditions. The studies were carried out in the coastal lagoon of the Mar Menor, which has been subjected to high anthropogenic nitrogen inputs for decades. While both macrophytes were efficient in exploiting NH4+ from the water column, only C. prolifera showed a high NO3- uptake capacity. Large N pools in the C. nodosa and C. prolifera meadows of the Mar Menor were detected, suggesting that these habitats may have the potential to be essential reservoirs for this nutrient. However, the major role of belowground tissues of the seagrasses in nitrogen accumulation may determine important differences between the two species in temporary N storage and sequestration. The data on N demands for the meadows of both macrophytes in the Mar Menor suggest an important contribution of these habitats in controlling the inputs of this nutrient into the lagoon. We conclude that C. nodosa and C. prolifera meadows can play a key role as a sink for dissolved inorganic nitrogen in temperate coastal lagoons, being an important mechanism of resistance to eutrophication. [ABSTRACT FROM AUTHOR]

In the Mediterranean, anthropogenic pressures (specifically those involving nutrient loads) have been progressively moved to deeper off-shore areas to meet current policies dealing with the protection of marine biodiversity (e.g., European Directives). However, conservation efforts devoted to protecting Posidonia oceanica and other vulnerable marine habitats against anthropogenic pressures have dedicated very little attention to the deepest areas of these habitats. We studied the remote influence of off-shore nutrient discharge on the physiology and structure of deep P. oceanica meadows located nearest to an urban sewage outfall (WW; 1 km) and an aquaculture facility (FF; 2.5 km). Light reduction and elevated external nutrient availability (as indicated by high δ15N, total N and P content and N uptake rates of seagrass tissues) were consistent with physiological responses to light and nutrient stress. This was particularly evident in the sites located up to 2.5 km from the WW source, where carbon budget imbalances and structural alterations were more evident. These results provide evidence that anthropogenic nutrient inputs can surpass critical thresholds for the species, even in off-shore waters at distances within the km scale. Therefore, the critical distances between this priority habitat and nutrient discharge points have been underestimated and should be corrected to achieve a good conservation status. [ABSTRACT FROM AUTHOR]

In the period 2016-2019, at the Research Institute of Mountain Stockbreeding and Agriculture, Troyan (Bulgaria), a field experiment was conducted to establish the impact of annual mineral fertilization on the bioproductive indicators of a degraded grassland with a predominant participation of grasses in mountain conditions. The data analysis shows a significant excess in dry mass yield in the variants with annual application of the combination N12P12 (4.03 t/ha) followed by the annual application of combined fertilization by N8P8 (3.41 t/ha). The values of the indicator exceeded the control by 156.77% and 124.71% (P < 0.001), respectively. The grasslands with combined application of N10P10 (3.34 t/ha) and with alternative alternation of nitrogen and phosphorus (N7/I P7/II P7/III/N7/IV - 3.31 t/ha) had a slight difference in the values of the studied trait, but with high provability compared to the control 120.10% and 118.47%, respectively (P < 0.001). The lowest productivity (2.91 t/ha) (but with a proven excess compared to the control) were the treated grasslands from the second alternative variant (P6/I N6/II P6/III/N6/IV). The excess over the control was 92.06% (P < 0.001). The applied fertilization rates contributed to the desired changes in the individual groups and species of the botanical composition of the degraded grassland. The dominant legume species were: Trifolium hybridum L., Vicia sativa L., Lotus corniculatus L. and Medicago lupulina L., and of grasses - Festuca arundinaceae Scherb., Festuca rubra L. and Agrostis capillaris L. The highest share of motley grasses were registered in the grasslands treated annually with N8P8 (by 39.3% compared to the control) and the lowest in the grasslands treated annually with N12P12 (by 18.4% compared to the control). [ABSTRACT FROM AUTHOR]

The smallest of the inhabited islands of the Balearic archipelago is also the only inhabited Spanish island without an airport. This circumstance, added to the fact that it is the southernmost island of the Balearic Islands, makes it unique by making it part of the most southern Mediterranean characteristics: little precipitation, a lot of light... On these conditions, its posidonia meadows have produced the sand of beaches that have amazed the observer of the rainy and dimly lit Northern Europe. All of this has made it one of the most select and unique destinations in the Western Mediterranean, with environmental, social and economic effects that are not always as positive as some statistics show. Some local initiatives try to counteract the negative effects of a tourist exploitation that could make the island die of success. [ABSTRACT FROM AUTHOR]

The onset of a major seagrass initiative in West Africa enabled important seagrass discoveries in several countries, in one of the least documented seagrass regions in the world. Four seagrass species occur in western Africa, Cymodocea nodosa, Halodule wrightii, Ruppia maritima and Zostera noltei. An area of about 62,108 ha of seagrasses was documented in the studied region comprising seven countries: Mauritania, Senegal, The Gambia, Guinea Bissau, Guinea, Sierra Leone and Cabo Verde. Extensive meadows of Zostera noltei were recorded for the first time at Saloum Delta, Senegal, which represents the new southernmost distribution limit of this species. This paper also describes the seagrass morphology for some study areas and explores the main stressors to seagrasses as well as conservation initiatives to protect these newly documented meadows in West Africa. The produced information and maps serve as a starting point for researchers and managers to monitor temporal and spatial changes in the meadows' extent, health and condition as an efficient management tool. [ABSTRACT FROM AUTHOR]

Invasive plants often drastically alter food webs. Small-mammal assemblages may be greatly impacted by invasive plants, which often provide cover from predators. In addition, a less-studied potential impact is the possibility that small mammals use invasive plants as a food resource. We quantified small mammal giving-up densities (GUDs) by offering fruits of 5 common invasive shrubs and 1 native shrub in adjacent meadow and forest habitats in Pennsylvania. The study ran for two 48-hour sessions in November in 2 consecutive years with different combinations of shrub fruits available to small mammals within buckets that also contained Panicum miliaceum (Proso Millet), and sand. While some degree of differences in foraging activity could be accredited to annual variation, significant differences in GUDs among fruit species and between habitats were detected. The fruits of the invasive shrubs Berberis thunbergia (Japanese Barberry), Ligustrum vulgare (Eurasian Privet), and Rhodotypos scandens (Jetbead) did not appear to be significantly foraged on by small mammals in either habitat. However, the woody liana Celastrus orbiculatus (Oriental Bittersweet) was readily consumed in both the forest and meadow. Fruits of the invasive shrub Eleagnus umbellata (Autumn Olive) was favored but only in meadow habitat, while fruits of the native shrub Lindera benzoin (Spicebush) were moderately foraged in the forest. Through this experiment, we were able to conclude that most woody plants included in this study offer fruits with limited perceived benefit. However, Oriental Bittersweet and Autumn Olive may represent important exceptions that could be influencing small-mammal foraging patterns in northeastern forest and meadow ecosystems. [ABSTRACT FROM AUTHOR]

Studies on the impacts of grazing on carbon, nitrogen, and phosphorus stoichiometry and storage are crucial for better understanding the nutrient cycles of grasslands ecosystems. Using a controlled grazing experimental platform in a meadow steppe ecosystem, the effects of different stocking rates (0.00, 0.23, 0.34, 0.46, 0.69, and 0.92 AU ha−1) on the carbon, nitrogen, and phosphorus contents of plant functional groups were explored. The major results were: (1) The carbon content of Gramineae Barnhart was significantly reduced by grazing intensity (p < 0.05), and the organic carbon content of Cyperaceae Rotundus was significantly higher than that of the other groups; the total nitrogen content of Cyperaceae and other groups and total phosphorus contents of Gramineae, Leguminosae Sp., Cyperaceae, and other groups all increased significantly with increasing grazing intensity (p < 0.05). (2) The carbon, nitrogen, and phosphorus storage amounts of Gramineae, Leguminosae, and Ranunculaceae L. decreased significantly with increasing grazing intensity. Heavy grazing reduced the carbon, nitrogen, and phosphorus storage amounts of Cyperaceae and other groups, while the carbon, nitrogen, and phosphorus storage amounts of Compositae were the largest under moderate grazing. (3) The nitrogen content of each functional group was highly significantly negatively correlated with the C/N ratio, and the phosphorus content was highly significantly negatively correlated with the C/P ratio. Grazing and foraging affected the growth of the different functional groups, which in turn affected their carbon, nitrogen, and phosphorus content, stoichiometry, and storage. Moderate grazing improved the nutrient utilization efficiency of grassland and is beneficial for promoting sustainable grassland development. [ABSTRACT FROM AUTHOR]

Aims: In northwestern North America, montane meadows fed by vernal ground-flow seepage occur scattered throughout an otherwise forested landscape on shallow soils over bedrock. Although their significance for biodiversity has been known, they have never been subject to systematic scientific research and thus, are not included in regional or national vegetation classification schemes. We provide the first vegetation survey of bedrock meadows and compare them to other major non-forest vegetation types in the region. Study area: Northwestern North America (United States, Canada). Methods: We surveyed 110 plots of bedrock meadow vegetation in Montana, Idaho, and British Columbia and compared them with data from 1052 plots from six studies of other open vegetation in the region: prairie and foothill grasslands, maritime mountain, alpine, and timberline meadows. We used cluster analysis to identify groups based on vascular plant composition, related abiotic and structural characteristics to clusters using non-metric multidimensional scaling (NMDS), and compared proportions of plant growth forms and life spans. Results: Cluster analysis identified five groups, with bedrock meadows forming a distinct community. According to the NMDS, bedrock meadows had a high cover of vascular plants, bryophytes, and lichens and a low cover of litter. Their climate was intermediate between maritime mountain and interior timberline meadows. A distinct functional feature of bedrock meadows was their high proportions of annual plants (therophytes) and plants regenerating from bulbs and corms (geophytes)--a functional composition they shared with maritime mountain meadows. Conclusion: Bedrock meadows have distinct floristic, functional, and environmental features, are important hotspots for biodiversity, and host several rare plant species. They are an important habitat for conservation and environmental impact assessment and should be incorporated into regional and national classification schemes. Future research priority should be given to understanding their spatial extent, ecological functioning, and drivers of non-vascular and vascular species richness. [ABSTRACT FROM AUTHOR]

Restoring habitats degraded by intensive agriculture is challenging, and the resulting communities often have lower quality and host fewer species than reference ecosystems. To improve restoration outputs, we need to understand what limits both establishment and performance of target species in restored populations. In this study, we focused on grassland restoration with regional seeds and compared the performance of two target herbs, Betonica officinalis and Centaurea jacea, between restored and reference populations. We also measured plant functional traits and environmental characteristics to understand which parameters affect population performance. Individual plants of both species were smaller in restored populations, which indicates reduced performance. Leaves of plants from restored populations contained more δ15N and, in Betonica, also less nitrogen and higher C:N ratio, which suggests that the performance of the target species may be limited by nitrogen. Nitrogen limitation of all restored communities was further corroborated by the low N:P ratio of bulk biomass. In Centaurea, we also recorded massive herbivory damage in restored populations, which likely further reduced this species' performance in restored meadows. In summary, target plants in restored populations showed lower performance than conspecifics in reference sites, probably due to nutrient imbalance (low nitrogen availability) and excessive herbivory damage. [ABSTRACT FROM AUTHOR]

Foliar fertilizing of meadow grass stand of type Chrusopogon gryllus L. type and pasture grass stand of Nardus stricta L. type with humate fertilizer, such as Biostim (400 ml/da) increases the crude protein content in dry matter by 34.2% and 31.3%, respectively. The highest energy and fodder nutritional value is the fodder mass of the variants treated with a dose of 400 ml/da (for Chrusopogon gryllus L.) and 200 and 300 ml/da (for Nardus stricta L.). The amount of gross energy in meadow grass stands is 1.0% lower than in pastures. The efficiency of the applied biofertilizer is most pronounced in the variants with 100 ml/da dose, where the amount of dry matter and crude protein reaches 808.80 kg and 79.55 kg - for meadow and 509.60 kg and 28.79 kg - for pasture grasslands. There is no difference in the total costs (7.87 BGN/da) regarding the application of foliar fertilizers in pasture and meadow grass stands. The total revenue, total profit, profitability and critical level of the yield from the conducted agrotechnical measure in the meadow grass stands are higher by 19.9%, 25.4%, 27.7% and 92.1% respectively compared to those of the pastures, but at a lower cost price. [ABSTRACT FROM AUTHOR]

Foliar endophytic bacteria and fungi are increasingly being recognized as important drivers of plant host phenotype—affecting a wide range of eco‐physiological processes. However, we are still lacking fundamental ecosystem‐level knowledge about the structure, function and inter‐species interactions in endophytic assemblages associated with plant hosts sharing a common life strategy or ecological specialization.In this study, we chose two groups of plants with contrasting physiology as model systems: parasites and their hosts. We assessed whether plant life‐history strategy, namely differences in nutrient acquisition and accumulation, plays a role in structuring above‐ground microbiomes under field conditions.We focused on the structure, colonization extent and potential function of foliar endophytic bacteria and fungi in three root hemiparasitic species (Orobanchaceae), one stem holoparasite (Convolvulaceae), and their potential host plants co‐occurring in species‐rich temperate grassland ecosystems. For this purpose, we combined next generation amplicon sequencing with quantitative real‐time PCR, chemical analyses of leaf tissue, and, in the case of bacteria, functional predictions using information deposited in available databases.We found the foliar endophytic assemblages to be diverse, dominated by generalist taxa, but highly similar across all studied species. Despite of the highly contrasting leaf tissue chemistry in the parasitic and non‐parasitic plant species, the parasitic trophic mode did not induce systematic shifts in the diversity, composition or predicted biogeochemical function of the endophytic microbiomes under field conditions. However, compared to their potential hosts, leaves of both hemiparasitic and holoparasitic species harboured significantly lower fungal counts, estimated as ß‐actin gene copies ng DNA−1, which suggests that parasitic plants may possess mechanisms to regulate the extent of colonization by endophytic fungi. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

The USDA‐ARS announces the release of the meadow bromegrass [Bromus biebersteinii Roem. & Schult. (excluded)] cultivar 'HighWest' (Reg. no. CV‐25, PI 698169) for use on irrigated and semi‐irrigated pastures as a rapidly establishing forage grass with excellent dry matter yield (DMY) on sites receiving 350 mm of either annual precipitation or irrigation. Selection emphasis in HighWest meadow bromegrass was on crude protein (CP), DMY regrowth, quality, and seedling emergence from a deep planting depth under irrigation. HighWest has been evaluated in Utah comparing it to meadow bromegrass cultivars 'Cache', 'Arsenal', 'Regar', 'Admiral', and 'Armada'. Genotyping by sequencing demonstrated that HighWest is significantly different genetically from Cache (P <.043), Arsenal (P <.003), Regar (P <.040), Admiral (P <.001), and Armada (P <.028) and grouped closest to Cache and Arsenal, consistent with its breeding pedigree. HighWest had greater (P <.05) percentage seedling emergence frequency at Millville, UT, compared with Arsenal, Regar, Armada, and Admiral. Based on a selection index that combined percentage seedling emergence frequency, DMY, and CP values, HighWest had a greater index value at 2.8 compared with Cache (1.7), Arsenal (−0.6), Regar (−3.2), Armada (−1.5), and Admiral (−1.0). Dry matter yield regardless of harvest date was similar to Cache, Arsenal, Regar, Admiral, and Armada. Forage regrowth of HighWest had CP values 6% greater than Cache. Water‐soluble carbohydrates were 22% greater in HighWest (87.0 g kg−1) than Cache. HighWest provides ranchers with additional plant material that maintains DMY and improves forage regrowth quality over the cultivar Cache. Core Ideas: HighWest is a new meadow bromegrass cultivar for use under irrigation and semi‐irrigation.HighWest has greater seedling emergence and vigor than most meadow brome cultivars.Based on combined seedling vigor, dry matter yield, and crude protein values, HighWest had greater index values.Water‐soluble carbohydrates values were always equal to, and sometimes greater than, other cultivars.Genetically, HighWest is distinct from other meadow brome cultivars in this study. [ABSTRACT FROM AUTHOR]

This research shows the results regarding the response to acidic condition of the sediment and Posidonia foraminiferal assemblages collected around the Panarea Island. The Aeolian Archipelago represents a natural laboratory and a much-promising study site for multidisciplinary marine research (carbon capture and storage, geochemistry of hydrothermal fluids and ocean acidification vs. benthic and pelagic organisms). The variability and the complexity of the interaction of the ecological factors characterizing extreme environments such as shallow hydrothermal vents did not allow us to carry out a real pattern of biota responses in situ, differently from those observed under controlled laboratory conditions. However, the study provides new insights into foraminiferal response to increasing ocean acidification (OA) in terms of biodiversity, faunal density, specific composition of the assemblages and morphological variations of the shells. The study highlights how the foraminiferal response to different pH conditions can change depending on different environmental conditions and microhabitats (sediments, Posidonia leaves and rhizomes). Indeed, mineral sediments were more impacted by acidification, whereas Posidonia microhabitats, thanks to their buffer effect, can offer "refugia" and more mitigated acidic environment. At species level, rosalinids and agglutinated group represent the most abundant taxa showing the most specific resilience and capability to face acidic conditions. [ABSTRACT FROM AUTHOR]

Zhang et al. ([29]) determined that linkages between community assembly processes and the abundance of soil nematode communities under nutrient enrichment may play a major role in the C cycling of meadow steppe ecosystems. China's meadow grasslands possess a total area of some 1.1 million km SP 2 sp , including meadow steppes (60,851 km SP 2 sp ), lowland meadows (252,196 km SP 2 sp ), montane meadows (167,189 km SP 2 sp ), and alpine meadows (637,206 km SP 2 sp ) (Liao and Jia [15]). 1 Outline map of the Chinese meadow steppe vegetation (adapted from Li et al. [11]) Of the 15 papers presented in this Special Issue, 12 concern meadow steppe communities at local and regional scales, based on either long-term stationary manipulative experiments, or off-site incubation tests, and transect surveys. Overgrazing has long been regarded as the most significant factor causing grassland degradation in China, while cultivation of grasslands has been most substantial in the meadow steppe region of Inner Mongolia and meadows in northeast China. [Extracted from the article]

Plasticity of plant functional traits plays an important role in plant growth and survival under changing climate. However, knowledge about how leaf functional traits respond to the multi-level N addition rates, multiple N compound and duration of N application remains lacking. This study investigated the effects of 2-year and 7-year N addition on the leaf functional traits of Leymus chinensis and Thermopsis lanceolata in a meadow grassland. The results showed that the type of N compounds had no significant effect on leaf functional traits regardless of duration of N application. N addition significantly increased the leaf total N content (LN) and specific leaf area (SLA), and decreased the leaf total P content (LP) and leaf dry matter content (LDMC) of the two species. Compared with short-term N addition, long-term N addition increased LN, LP, SLA, and plant height, but decreased the LDMC. In addition, the traits of the two species were differentially responsive to N addition, LN and LP of T. lanceolata were consistently higher than those of L. chinensis. N addition would make L. chinensis and T. lanceolata tend to "quick investment-return" strategy. Our results provide more robust and comprehensive predictions of the effects of N deposition on leaf traits. [ABSTRACT FROM AUTHOR]

The current warming of the Mediterranean Sea has been forecast to lead to the shrinkage of seagrass meadows. We agree that rising sea temperatures most likely will have immediate negative effects on them because present-day asexually reproducing clones of Posidonia oceanica were likely selected as a form of resistance under suboptimal conditions during the colder temperatures of the last glaciation. However, since the evolution of P. oceanica has happened under tropical/subtropical conditions for tens of millions of years, some kind of evolutionary resilience to high temperatures is to be expected. We suggest that the ability of P. oceanica plants to reproduce sexually when water temperature is >27°C might lead in the future to the selection of warm-loving plants (as warm-sensitive clones decline), with an associated increase in genetic variability in the species gene pool. Predictions focused exclusively on the future decline of cold-selected (warm-sensitive) clones may result in short-sighted forecasts because the deep history of the taxon is overlooked. We suggest that an evolutionary-based approach should be more often considered when analysing the present declines of animal and plant species. We provide some additional examples of cases in which this could be done. [ABSTRACT FROM AUTHOR]

Abstract—The variability and phytocenotic plasticity of morphological characters in Gymnadenia conopsea (L.) R. Br. individuals and the size, density, age structure, and vitality of 11 fragrant orchid coenopopulations were studied in the Kabardino-Balkarian Republic in the years 2015–2019. The variability and plasticity of the characters of plants ensure their adaptation to various growth conditions and the morphological heterogeneity of their coenopopulations. The dynamics of the abundance, density, age structure, and vitality of coenopopulations in the changing environment provides information on the life strategies of species. The above-ground parts of G. conopsea individuals were used to assess their age state, variability, and plasticity (i.e., the plants were not dug out of the earth). The studies were conducted in meadow plant communities affected by various anthropogenic impacts (recreation and cattle grazing). In changing growth conditions, the species demonstrates medium–high phytocoenotic plasticity (Ip = 38–68%) and high variability of morphological characters (CVx–mean = 17.10–33.63%). In undisturbed wet meadows, the growth processes intensify in G. conopsea individuals, the vitality of their coenopopulations reaches the maximum level (IVC = 0.98–1.16), and the share of generative individuals in the age spectra increases to 48.6–56.5%. With intensification of the anthropogenic impact, the vitality and density of coenopopulations decrease (IVC = 0.82–0.95), the share of virginal individuals increases in the age spectra (on rubble substrates), or the coenopopulations start steadily ageing (in mesophilous meadows). In the absence of anthropogenic pressure, the seed reproduction intensity is high in coenopopulations developing in grass stands with low (60%) projective cover on rubble substrates; the density of individuals in such coenopopulations amounts to 16 ind./m2. G. conopsea features a mixed life strategy type involving both stress-tolerant and explerent (ruderal) components. The explerent–stress-tolerant life strategy enables the species to withstand intense interspecies competition and anthropogenic pressure for a long time and quickly colonize unoccupied areas. [ABSTRACT FROM AUTHOR]

We contribute to the knowledge of charophyte meadows as key components of aquatic systems by analysing how they affect wetland sediments. We performed a factorial-design experiment with limnocorrals (outdoor mesocosms) in a Mediterranean protected wetland with presence or absence of charophytes [Chara vulgaris (CV) and Chara hispida (CH), planted from cultures or recruited in situ from germination of their fructifications]. The first 1 cm-surficial and 2 cm-bottom sediment layers were analysed for cladoceran ephippia, ostracods valves, benthic community of bacteria and periphytic biofilm, and charophyte fructifications. In the surficial sediment, the ephippia density was fourfold higher in the conditions with charophytes than in sites with no-charophytes and higher apparent viability was found. The surficial sediment periphyton biofilm was composed mainly of diatoms, with tenfold higher biomass underneath charophytes, and a much diverse community. The specific microhabitat generated by each charophyte species was reflected in the different abundances and relationships between the analysed components, firstly establishing a divergence with the sediment without meadows and, secondly, a distinction between the meadows of CH and CV that exhibit particular morphology-architecture, might exudate different metabolites and might have different allelopathic capacities over microalgae and microinvertebrates. Thus, the charophyte–sediment tandem is relevant for biodiversity and habitat conservation. [ABSTRACT FROM AUTHOR]

Investigating the direction of changes in functional diversity involving successional pathways and historical disturbances may be a promising tool for predictions of the effectiveness of the seminatural meadows conservation, with great emphasis on formulation of more cost‐effective restoration strategies. The goal of this research was to assess the differences in long‐term shifts in the functional diversity of plant species in seminatural wet meadows unmanaged for the last 40 years, under the influence of different successional pathways and historical disturbances. Using ordination techniques, linear mixed‐effect models, a set of plant functional traits and parameters of functional diversity, we assessed the importance of habitat filtering, competition, and niche partitioning in shaping community assembly changes over time. The most dramatic shifts in functional diversity were found in the Carex acutiformis successional pathway after topsoil removal, where colonization by successional inhibitors was the main driver causing decreases in functional dispersion and divergence. This was expressed as a decrease in the importance of habitat filtering and replacement of specialized species by competitors with heavier seeds and higher specific leaf area. Regarding the C. cespitosa and Salix cinerea pathways, the magnitudes of shifts in functional diversity were milder and differed less between the historical topsoil removal and mowing treatments, thereby maintaining a large role for niche partitioning in shaping the vegetation structure. The results of our study highlight the importance of tussock sedges and shrubs as effective buffers against the functional homogenization of meadows driven by the decreases in functional diversity of plant species, even from a long‐term perspective. [ABSTRACT FROM AUTHOR]

Alien goldenrods (Solidago and Euthamia) invade improperly managed grasslands causing serious environmental problems. The general knowledge regarding habitat resistance against invasion does not allow predicting whether species-rich seminatural meadows or highly productive artificially sown grasslands are more resistant to invasion by goldenrods. To test the differences in resistance, an experiment was conducted. A community resembling a semi-natural, species-rich meadow and a commercial grassland was created in containers in 2018 using seed mixes, with open soil serving as the control. Three goldenrod seedlings representing particular species (Solidago canadensis L. s.l., S. gigantea Aiton, and Euthamia graminifolia (L.) Nutt.) were planted in the test containers with the different communites in 2019. The vegetation was cut once per year during the first and second years of the experiment. In September of the third year, the number of goldenrod ramets, the height of the tallest goldenrod ramet, and the flowering stage were measured and assessed. In addition, the dry biomass of goldenrods and accompanying species were weighed. The results showed no significant differences between total biomass production of the examined communities, except for E. graminifolia, for which species-rich meadow produced more biomass than the commercial grassland and control. Both communities strongly reduced ramet numbers and height and goldenrod biomass production compared to the control. No differences were found between these two vegetation types, except for the flowering stage of S. canadensis and E. graminifolia, which could not produce seeds in the species-rich meadow community. The results suggest that semi-natural, species-rich meadows are reasonable alternatives to species-poor commercial grasslands to control goldenrod invasion. [ABSTRACT FROM AUTHOR]

Submerged aquatic vegetation, and especially charophytes, which are an important habitat for many species, have declined in the Baltic Sea due to changes in light climate, eutrophication and physical disturbance. Physical disturbance in the form of small-scale dredging activities is commonplace in Sweden due to land uplift, but causes fragmentation of coastal habitats. Here we test three planting methods for restoration of the charophyte Chara aspera on an area of deposited sediment, and a single method for restoration of C. tomentosa in a dredged area. We found that none of the planting methods tested was more successful than natural recolonization of C. aspera on the deposited sediment. C. tomentosa planting was unsuccessful in the dredged area and was likely outcompeted for light by taller species. The C. aspera meadow was resilient to smaller disturbances, as experimental removal of up to 2.5% of C. aspera and sediment from the donor area did not reduce C. aspera coverage a month after removal. Even after an uncontrolled event that removed up to 50% of C. aspera in the experimental plots, C. aspera coverage had returned to pre-removal levels a year after the disturbance. We suggest future restoration experiments test transplanting sediment rich in oocytes and bulbils into areas with suitable light climates and low competition with other species. Restoration efforts are costly and highly uncertain of success, therefore we recommend discontinuing dredging activities in charophyte meadows to protect this important habitat. • Four planting methods did not increase charophyte recolonization of a disturbed area. • Dense undisturbed C. aspera meadows can be resilient to removal of small areas. • Restoration of charophyte meadows is difficult and expensive. • Avoiding dredging activities in charophyte meadows is essential to stop habitat loss. [ABSTRACT FROM AUTHOR]

In the coastal environment, a large amount of microplastics (MPs) can accumulate in the sediments of seagrass beds. However, the potential impact these pollutants have on seagrasses and associated organisms is currently unknown. In this study, we investigated the differences in MPs abundance and composition (i.e., shape, colour and polymer type) in marine sediments collected at different depths (−5 m, −15 m, −20 m) at two sites characterized by the presence of Posidonia oceanica meadows and at one unvegetated site. In the vegetated sites, sediment samples were collected respectively above and below the upper and lower limits of the meadow (−5 m and −20 m), out of the P. oceanica meadow, and in the central portion of the meadow (−15 m). By focusing on the central part of the meadow, we investigated if the structural features (i.e. shoots density and leaf surface) can affect the amount of MPs retained within the underlying sediment and if these, in turn, can affect the associated benthic communities. Results showed that the number of MPs retained by P. oceanica meadows was higher than that found at the unvegetated site , showing also a different composition. In particular, at vegetated sites, we observed that MPs particles were more abundant within the meadow (at – 15 m), compared to the other depths, on unvegetated sediment, with a dominance of transparent fragments of polypropylene (PP). We observed that MPs entrapment by P. oceanica was accentuated by the higher shoots density, while the seagrass leaf surface did not appear to have any effect. Both the abundance and richness of macrofauna associated with P. oceanica rhizomes appear to be negatively influenced by the MPs abundance in the sediment. Overall, this study increases knowledge of the potential risks of MPs accumulation in important coastal habitats such as the Posidonia oceanica meadows. [Display omitted] • High Posidonia oceanica densities can retain microplastics in sediments. • Transparent fragments of polypropylene dominate in vegetated sediments. • Microplastics negatively affect macrofauna communities associated with P. oceanica. [ABSTRACT FROM AUTHOR]

Questions: Agricultural intensification has led to the decline of biodiverse meadows and other semi‐natural grasslands. Road verges offer potential alternative habitats for meadow species, but they may not be suitable for all meadow species due to different soil properties, frequent disturbances, pollution or suboptimal management. Are their communities of vascular plants and bryophytes similar or dissimilar to those in mown or grazed meadows? What kind of species are associated with road verges, mown meadows or grazed meadows? How do the habitat types differ in their soil conditions and disturbance intensity? Location: The study was conducted at 36 sites in central Finland. Methods: We compared the vascular plant and bryophyte flora and the habitat characteristics of road verges, mown meadows and grazed meadows. Results: The community composition of both vascular plants and bryophytes differed among the habitat types. Many species occurred in all three habitat types, but several meadow specialists were absent or less frequent in the road verges. In contrast, road verges hosted more forest species and ruderal species, especially bryophytes. Road verges differed from meadows in their soil conditions. Conclusions: We conclude that although road verges may host some species typical to meadows, their value as alternative habitats could be increased by improved soil preparation and vegetation management. Meanwhile, the continued decline of quality habitats for meadow species underscores the need to maintain, increase and improve meadow management. [ABSTRACT FROM AUTHOR]

The Lakes Amvrakia and Ozeros (W. Greece) belong to the western chain of Greek wetlands running along the coast of the Ionian Sea. They are both natural lakes belonging to the Natura 2000, Site of Community Importance (pSCI) and are characterized by high ecological value. Wet meadows are typical habitat types of these wetland ecosystems which are in contact with rural ecosystems which they interact with. Due to the high conservation value of these habitat types, in the framework of this study the flora of the wet meadows was recorded and a floristic analysis concerning chorology, life forms and habitat preferences was made. A total number of 152 taxa was found in the wet meadows of both lakes from which only 47 taxa were common. The families with the greatest number of species were Fabaceae (22 taxa), Asteraceae (14 taxa) and Poaceae (9 taxa) for the wet meadow vegetation of the Lake Amvrakia and Fabaceae, Poaceae (17 and 13 taxa, respectively) for the Lake Ozeros. In both lakes the prevalence of the Therophytes is evident, while the life forms of Chamephytes and Aquatics were absent from the Lake Amvrakia. From the results of the canonical correspondence analysis among species, sampling plots and selected environmental variables, a clear separation between species and sampling plots was found, presenting strong correlation with specific edaphic parameters (pH, CaCO3, EC, Polsen, Total N, SOC and NO-3). These edaphic properties, as a result of natural and anthropogenic interventions, seem to play an important role in the wet meadows plant species distribution pattern. [ABSTRACT FROM AUTHOR]

Investigating non‐random assemblages emerging in response to environmental gradients is relevant to understand mechanisms and processes affecting biodiversity. Species may be filtered from fractions of environmental gradients that limit dispersal, survival or ontogenetic development, which ultimately leads to biotic complementarities among sites. Non‐random assemblages as a response to environmental filtering have been widely demonstrated in Amazonian forests, but are rarely assessed in non‐forest ecosystems such as macrophyte meadows covering lakes. In this study, we sampled 50 plots (50 m long, 6 m wide) along continuous macrophyte meadows in a lake system in the lower Amazon River. Our main goal is to test the effects of distance from the lake bank, macrophyte height and composition (frequency of morphotype occurrence), air temperature and physicochemical properties of water (pH, dissolved oxygen, depth and temperature) on frog α and β‐diversity estimates, and frequency of species traits occurrence (abundance‐weighted body size, toe pads, foot webbing and tadpole habit). We found 16 species, for which local assemblages quantified by α and β‐diversity estimates were not random, but predicted by macrophyte height, morphotype composition and water depth. We have explicitly shown that species are filtered from fractions of these gradients through ecomorphological relationships, since morphological traits and tadpole habits were also selected by the vertical stratification provided by the vegetation cover and water depth. Overall, we present an investigation of assemblage ecology that is relevant to conservation, because the results suggest biotic complementarities within habitats that are rarely considered as distinct biogeographic units from the surrounding várzea forests. Abstract in Portuguese is available with online material. [ABSTRACT FROM AUTHOR]

We report a 12‐yr data set (August 2006–October 2018) of nearly continuous estimates (n = 3275) of gross primary production (GPP), community respiration (CR), and net community production (NCP) in a Posidonia oceanica seagrass meadow, computed from O2 measurements on a mooring at 10 m bottom depth in the Bay of Revellata (Corsica). Both NCP and CR were correlated to GPP and followed the leaf biomass seasonal cycle. The meadow was net autotrophic (NCP of 23 ± 8 mol O2 m−2 yr−1, GPP [83 ± 16 mol O2 m−2 yr−1] > −CR [−60 ± 9 mol O2 m−2 yr−1]), in agreement with oxygen oversaturation (104% at annual scale, 101% in winter, and 109% in summer). Calcification (CAL) and CaCO3 dissolution (DIS) rates were evaluated from dissolved inorganic carbon measurements in benthic chamber incubations (August 2006–2009). The meadow was found to be a net sink of CaCO3 (DIS > CAL) at an annual rate of 7 mol CaCO3 m−2 yr−1 that matched estimates of CaCO3 deposition on the meadow by sedimentation from the water column. CAL from epiphyte coralline algae was correlated to GPP, but CAL : GPP ratio (0.1) was lower than reported for coralline algae in cultures (0.6) due to the additional contribution of Posidonia to GPP. Both NCP and net DIS contributed to an annual CO2 sink of −30 mol CO2 m−2 yr−1 distinctly stronger than the estimated net air‐sea CO2 flux (−1 mol CO2 m−2 yr−1). This suggests that CO2 input by vertical mixing and/or transport by horizontal advection also strongly contribute to the net atmospheric CO2 exchange. [ABSTRACT FROM AUTHOR]

Introduction: Both intensification and abandonment of traditional agricultural practices are known to be major threats to biodiversity worldwide. Land abandonment, in particular, has a negative effect on the diversity of both plant and insect communities, although few studies have analysed the effects on the interactions between both groups. Given the importance in maintaining mutualistic interactions between plants and pollinators, it is essential to know how the structure of pollination networks changes in the process of abandonment of traditionally managed habitats and also to determine to what extent it is re-established when such habitats are restored. Methods: We monitored a butterfly-plant network over a long period (22 years) in habitats where land abandonment and restoration had taken place. This has allowed to analyse the long-term effects of such processes on both plant and butterfly communities and the interactions between them. Results and discussion: Abandonment led to significant reductions in the cover of typical grasslands plants, resulting in changes in butterfly assemblages and plant-butterfly interactions. Specifically, it caused a replacement of multivoltine by monovoltine species, increasing thus network specialization as the latter established interactions with fewer plants. A grassland restoration combining mowing and grazing promoted a quick return to the pre-abandonment situation in the butterfly community. Moreover, such restoration practice increased network generalization and nestedness, network descriptors known to enhance community stability. Implications for insect conservation: Maintaining traditional management practices in these semi-natural meadows is an effective way to preserve their biodiversity, understood not only as the number of species but also as the number of interactions that butterflies establish with nectar sources. [ABSTRACT FROM AUTHOR]

Wild ungulates seek out food resources at the bottom of mountain valleys in winter and spring, where their high density can negatively impact the production of hay meadows. This study determines the factors that explain the meadow use of four sympatric species: red-, roe-, and fallow-deer, and wild boar. In 2017, we counted the individuals of each species in 94 meadows for eight nights, between March and June, and estimated the frequency of meadow use as the proportion of positive censuses over the total censuses per meadow. We also recorded the presence of domestic ungulates. We inventoried the floristic composition in June. Species tended to use different meadows but only fallow- and roe-deer significantly segregated, indicated by the negative C-score index. As the ungulate frequency was skewed to 0, we used a generalized additive model (GAMLSS) to simultaneously simulate the probability of animals being absent and the frequency of positive censuses. Landscape features contributed to explaining the absence probability, while plant richness and legume cover explained the frequency of meadow use. The presence of domestic ungulates did not affect wild ungulate behavior. All studied species, except roe-deer, avoided exposed spots, preferentially using large meadows close to the forest. At meadow level, each species seemed to have different forage requirements. The frequency of fallow deer increased with the meadow forage quality, indicating a more grasses-based diet than the other two deer, and probably displacing roe-deer to suboptimum meadows. Red-deer used less plant-rich meadows, suggesting flexibility in their dietary choices. [ABSTRACT FROM AUTHOR]

Methodological papers advise to collect moss surface samples either at the beginning or at the end of the flowering season. In reality, such collections occur often within the flowering season for purposes of vegetation description or because of accessibility of remote study areas. Here we test whether the season of moss surface sample collection has an influence on pollen spectra. Ten moss/litter samples were collected in different habitats of the natural reserve 'Spasskaya Gora' (Perm region, Russia) in July and September from the same locations exactly. The results show that pollen assemblages reflect well the present dominant vegetation of Pinus-Betula-forests and grasslands and demonstrate differences between open and forested areas as well as between abandoned fodder meadows and semi-natural hay meadows in use. Paired t-tests and Wilcoxon tests demonstrate that the dominant pollen taxa Pinus diploxylon-type, Betula and Poaceae as well as the rarefied number of pollen taxa do not differ significantly between seasons, while values of Artemisia are significantly higher in September. A significant decrease in pollen concentration in September indicates the importance of washing-out of pollen by precipitation. PCA results demonstrate the similarity of the pollen spectra between the seasons. Based on our results, we conclude that the season of surface sample collection does not significantly influence the pollen assemblages and appropriate field studies can be carried out in summer during the flowering season. However, we strongly recommend to collect bulk samples of mosses with basal parts and/or litter with surface soils in order to ensure representation of the average pollen signal for the previous years and to dilute local extremes in the pollen deposition. [ABSTRACT FROM AUTHOR]

The restoration of a threatened type of seminatural grassland—the Baltic Boreal coastal meadows—began in Estonia in 1997. The main causes of degradation of these communities were land abandonment and overgrowth by reed. In 2015, we resurveyed 14 sites and classified as (1) permanently managed or (2) restored before 2005, or (3) after 2005. In 2015, all sites were managed under the EU agri‐environmental scheme and classified as permanently managed or restored before or after 2005. The resurvey focused on assessment of the long‐term success of restoration, comparing the vegetation parameters of restored meadows with permanently managed meadows (which were considered as reference). Our study revealed that historical management patterns have an impact on the species richness of these habitats, as more species were found in historically mown meadows, even if the sites were restored by grazing. However, species richness was not an important indicator of coastal meadow recovery. The best indicators of restoration success are evenness and coverage of low‐lying, light‐demanding, salt‐tolerant, wintergreen, cryptophyte, and hemicryptophyte plant species. Phragmites australis is a good indicator species for the habitat, as its abundance indicates poor habitat quality. The study indicated that the recovery of coastal meadow habitat from abandonment requires more than 15 years of restoration activities, and suggested the 3‐year restoration period covered by conservation measures and funds is not enough. Therefore, we recommend that agri‐environmental schemes should support additional restoration activities for recently restored meadows which are entering the management scheme. [ABSTRACT FROM AUTHOR]