Peak In Richness Research Articles

Emission spectrum and photon statistics in cavity-QED system under incoherent pumping

The emission spectrum is an important tool for studying the properties and interactions of matter. By comparing analytical and numerical solutions, we validate the applicability and limitations of the low-excitation approximation. Here we show that even with a moderate pumping rate, rich multiple peaks can be observed in the emission spectrum which is the result of excitation of higher dressed rungs. Moreover, we find distinct photon distributions in the steady state under different pumping and coupling conditions and the physical mechanisms behind these phenomena are also illustrated. Additionally, we also show that the interference between the emission channels of the emitter and cavity can result in asymmetry of the emission spectrum of the whole system even if the emitter is resonant with the cavity field. Our findings can help in understanding the nonlinear characteristics and photon statistics in the cavity-QED systems.

Plant species richness (PSR) along island biogeographical gradients in inhabited islands of Shinan-gun, Republic of Korea

The objective of this study is assess the influences of 8 environmental factors, population, coastline length, island area, vegetated area, highest peak, distance to the mainland, longitude, latitude on vascular plant species richness (PSR) of 10 inhabited islands of Shinan-gun, South Korea. In simple regression, the relationships between PSR and distance to the mainland, longitude and latitude were significant at the 5% level. When distance increases, longitude and latitude decrease, plant species richness increases. The relationship between PSR and coastline length, island area and highest peak were not significant at 5% level. But coastline length, island area and vegetated area showed negative relation with plant species richness and highest peak showed positive relation. Relationship between population and PSR was not statistically significant and showed negative relation. This may indicate PSR decrease by the effects of human dynamics, but further research is needed. In stepwise regression method three variables, distance, longitude and latitude, explained 98.0% of the variation in PSR.

Environmental DNA Reveals the Impact of Submarine Groundwater Discharge on the Spatial Variability of Coastal Fish Diversity.

Submarine groundwater discharge (SGD) has recently been recognized as an influential factor in coastal ecosystems; however, little research has been conducted on its effects on coastal fish diversity. To investigate the relationship between SGD and fish diversity, we conducted a survey at the coastal island scale using the environmental DNA (eDNA) method. Our findings indicate that fish species richness and functional richness peak at stations with high SGD. Environmental variables, such as salinity, dissolved inorganic nitrogen (DIN) concentration, and SGD, significantly influence fish diversity. Carnivore fish richness was negatively correlated with salinity, while planktivore fish richness was positively correlated. Additionally, SGD and DIN concentrations were found to be crucial in shaping omnivorous and pelagic communities, respectively. This study highlights the role of SGD in enhancing nutrient conditions favorable for diverse fish communities and demonstrates the effectiveness of eDNA metabarcoding for rapid marine biodiversity assessment. These findings provide valuable insights for coastal ecosystem monitoring and management.

Ant impacts on global patterns of bird elevational diversity.

Using data on bird species elevational distributions from the world's mountain ranges, bird diets, and the distribution of the ant genus Oecophylla, we report that global patterns in bird elevational diversity show signals of competition with ants. Oecophylla is an abundant and effective predator of invertebrates, preying on the same species that invertivorous birds feed on. In mountain ranges with Oecophylla present in the foothills, the maximum species richness of invertivorous birds (but not other trophic guilds) occurs, on average, at 960 m, ca. 450 m higher than in mountain ranges without Oecophylla, resulting in a mid-elevation peak in bird species richness. Where Oecophylla is absent, bird species richness for all guilds generally show monotonic declines with increasing elevation. We argue that Oecophylla reduces prey density for invertivorous birds and that low prey abundance reduces invertivorous bird density, which in turn is correlated with lower bird species richness. These findngs suggest that competition between distantly related taxa can set range limits, leading to emergent diversity patterns over large scales.

Microhabitat diversity – A crucial factor shaping macrofungal communities and morphological trait expression in dead wood

The majority of studies exploring the ecology of saprotrophic fungi have worked with individual logs as homogenous sampling units, neglecting the presence of microhabitats and inner complexity. Based on close to 7000 sporocarp records of more than 450 fungal taxa from 134 decaying beech logs we investigated microhabitat preferences in macrofungi and linked these to sporocarp traits. The respective microhabitats were defined by the local wood decay stage, vertical position on the fallen log and special habitat features (hollows, fracture surfaces, woody material fallen from the log). We found microhabitat associations to be non-random in relation to fungal community composition and sporocarp morphology, indicating an evolutionary link between dead wood niche and sporocarp morphology. While log-level fungal species richness peaked at intermediate decay stages, taxa with significant indicator values were skewed towards early and late decay stages, when defined at microhabitat decay level. This suggests that the commonly found peak in fungal species richness on dead logs in intermediate decay stages expresses a peak in niche diversity rather than a peak in taxa decay stage preferences.

Linking hydrological connectivity with the richness and composition of aquatic invertebrates across the Paraná River floodplain, Argentina

Lateral hydrological connectivity can affect the community characteristics by promoting dispersal of organisms between the river and its floodplain. We investigated the species richness, specific diversity, and relative abundance of microcrustaceans transported by the flood and the macroinvertebrates retained by Pontederia crassipes Mart. roots in five floodplain lakes with different connectivity within the RAMSAR Site Humedales Chaco. Due to differences in the slopes of the floodplain studied, the connectivity was determined by the topographic location of each lake, rather than by the distance from the river. During the hydrological connection, there was a transverse gradient in the physical and chemical characteristics of the water, with an increase in the electrical conductivity and a decrease in dissolved oxygen and suspended solids in the more isolated sites. A total of 62 species of microcrustaceans (48 cladocerans and 14 copepods) and 63 taxa of macroinvertebrates were identified. The microcrustaceans had high species richness in the three most connected lakes, whereas the macroinvertebrates had a peak in taxa richness in the lakes with intermediate connectivity. The low beta diversity (βw) for both microcrustaceans (14.63 %) and macroinvertebrates (16.9 %) indicated that taxa richness varied little between sites with different hydrological connectivity. In both assemblages, cluster analysis based on the similarity of the relative abundance grouped the three sites more connected and separated from the less connected sites. Our results suggest that species richness followed different patterns in different assemblages across the lateral gradient and that the hydrological connectivity was more related to the relative abundance of microcrustaceans and macroinvertebrates than to the classical measures of βw. Species diversity indices did not vary between sites. The high total species richness of invertebrates is mainly a result of the spatial arrangement of the different floodplain lakes.

Masses of the conjectured H-dibaryon at different temperatures*

Abstract We present a lattice QCD determination of masses of the conjectured H-dibaryon, denoted as , at nine different temperatures: 0.24, 0.63, 0.76, 0.84, 0.95, 1.09, 1.27, 1.52, and 1.90. The masses of baryons N, Σ, Ξ, and Λ at different temperatures were also computed. The simulations were performed on an anisotropic lattice with flavours of clover fermion at a quark mass corresponding to . The thermal ensembles were provided by the FASTSUM collaboration, whereas the zero temperature ensembles were provided by the Hadspec collaboration. We also calculated the spectral density of the correlation function of those particles. The spectral density distributions show a rich peak structure at the lowest temperature; at intermediate temperatures, the mass values of those particles obtained by the extrapolation method reflect a two-peak structure. While the spectral density for the octet baryon becomes smooth at 1.27, 1.52, and 1.90, the spectral density for the H-dibaryon becomes smooth at . At , the mass difference of the H-dibaryon and Λ pair, expressed as , was estimated to be MeV, which suggests the existence of a bound H-dibaryon state.

Distribution Patterns of Gymnosperm Species along Elevations on the Qinghai–Tibet Plateau: Effects of Climatic Seasonality, Energy–Water, and Physical Tolerance Variables

Climate change is one of the most prominent factors influencing the spatial distribution of plants in China, including gymnosperms. Climatic factors influence gymnosperm distribution along elevational gradients on the Qinghai–Xizang (Tibet) Plateau (QTP), and understanding how species adapt to these factors is important for identifying the impacts of global climate change. For the first time, we examined the county-level distribution of gymnosperm species on QTP using data from field surveys, published works, monographs, and internet sources. We used simulated distribution data of gymnosperms (N = 79) along the elevational gradients to investigate the overall impact of environmental variables in explaining the richness pattern of gymnosperms. Eighteen environmental variables were classified into three key variable sets (climatic seasonality, energy–water, and physical tolerance). We employed principal component analysis and generalized linear models to assess the impact of climatic variables on the gymnosperm’s richness pattern. Gymnosperm species are unevenly distributed across the plateau and decline gradually from the southeast to the northwest. The altitudinal gradients have a unimodal relationship with the richness of gymnosperms, with the maximum species richness at an elevation of 3200 m. The joint effects of physical tolerance and energy–water predictors have explained the highest diversity of gymnosperms at mid-elevation. Because the richness peak correlates significantly with the wettest month’s precipitation and moisture index, this confirms the significance of moisture on gymnosperm distributions due to increased precipitation during the wet season. Furthermore, our results provide evidence that climatic seasonality factors are involved in the decline of gymnosperm richness at high elevations. A total of 37% of gymnosperm species on QTP are listed as vulnerable, nearly threatened, or endangered, with elevations ranging from 600 m to 5300 m. As a result, we conclude that gymnosperms are at high risk of extinction because of the current climate fluctuations caused by global climate change. Our research offers fundamental data for the study and protection of gymnosperm species along the steepest elevation gradients.

Exploring the impact of data curation criteria on the observed geographical distribution of mosses.

Biodiversity data records contain inaccuracies and biases. To overcome this limitation and establish robust geographic patterns, ecologists often curate records keeping those that are most suitable for their analyses. Yet, this choice is not straightforward and the outcome of the analysis may vary due to a trade-off between data quality and volume. This problem is particularly recurrent for less-studied groups with patchy sampling effort. The latitudinal pattern of mosses richness remains inconsistent across studies and these may emerge purely from sampling artefacts. Our main objective here is to assess the effect of different curation criteria on this spatial pattern in the Temperate Northern Hemisphere (above 20° latitude). We contrasted the geographical distribution of moss species records and the latitude-species richness relation obtained under different data curation scenarios. These scenarios comprehend five sources of taxonomical standardisations and eight data cleaning filters. The analyses are based on the selection of well-surveyed cells at 100 km cell resolution. The application of some 'data curation scenarios' severely affects the number of records selected for analysis and substantially changes the proportion of richness per cell. The sensitivity to data curation becomes detectable at regional and at the cell scales showing a large shift in the latitudinal richness peak in Europe, from 60° N to 45° N latitude, when only preserved specimens are selected and duplicates based on date of collection and coordinates are excluded. Our results stress the importance of justifying the criteria used for filtering biodiversity data retrieved from biodiversity databases to avoid detecting misleading patterns. Curating records under particular criteria compromises the information in some areas displaying different spatial information of mosses. This problem can be ameliorated if data filtering is combined with identifying well-surveyed cells, render relatively constant results under different combinations of filtering even for less well-known groups such as mosses.

Porcelaneous larger foraminiferal responses to Oligocene–Miocene global changes

Sea surface temperatures (SST) have been identified as a main controlling factor on larger benthic foraminifera (LBF) living in tropical to sub-tropical shallow-water carbonate and mixed siliciclastic‑carbonate platforms. Changes in SST, along with those in ocean acidification and nutrient content recorded in the global oceans throughout their history will not only continue but also be amplified in the future at an unprecedented rate of change possibly reaching levels found in the geological record. This study focuses on the Oligocene (mean SST 8 °C higher than present) and the Miocene (SST 5–8 °C higher than present) epochs which were characterized by a higher richness in porcelaneous LBF (pLBF) than today. A systematic re-assessment and comprehensive literature survey of stratigraphic ranges and palaeogeographic distribution in the Western Tethyan (Mediterranean) and Indo-Pacific regions are used to evaluate the impact of changes in SST, seawater pCO2 and pH on the biodiversity of the Oligocene–Miocene pLBF Alveolinella, Austrotrillina, Borelis, Bullalveolina, Flosculinella, and Praebullalveolina. Two peaks in species richness were identified during the Aquitanian and Langhian–Serravallian. These peaks occurred when SST was ∼29 °C, with pCO2 of ∼400 ppm and pH > 7.8. These values are comparable to those of today. The minima in species richness recorded in the Rupelian–early Chattian, in the Burdigalian and from the Tortonian onward can be correlated to the detrimental effects of both minimum (< 26 °C) and maximum (> 31 °C) SST thresholds. High pCO2 (> 600 ppm) values, which are limited to the Rupelian–early Chattian, are also detrimental to species richness. Seawater pH higher than 7.7 did not negatively affect species richness. These historical trends have serious implications for the future diversity of pLBFs with the increasing likely scenario of rising SST and pCO2 and lowering of pH values in the near future. These developments can potentially lead to diversity decrease and even extinction of pLBFs. However, the resilience of present-day pLBF species to rising SST and pCO2 levels is underpinned by the evolutionary histories of their fossil counterparts during climate variations, albeit at much different rates of change.

High-sensitive nonthermally coupled upconversion for ultralow temperature sensing

Upconversion based nanothermometry has received much attention due to its merits of stability, narrow band emission and rich emission peaks. However, the previous works are mainly focused on the emissions from thermally coupled energy levels which is theoretically limited by Boltzmann distribution theory with resultant low temperature sensitivity in particular at ultralow temperatures. Here we report a LiYF4:Yb/Ho@LiYF4 core-shell nanostructure to improve the sensitivity at low temperatures by taking advantage of non-thermally coupled energy levels of Ho3+. In detail, the green upconversion emission of Ho3+ shows an increase with reducing temperature while its red upconversion emission presents a decline during the same process. This is primarily due to the suppression of the non-radiative multi-phonon relaxation occurred at the green emitting levels (5F4,5S2) and the intermediate level (5I6) at low temperatures. Such a feature contributes to a high relative sensitivity of 7.17%/K at 11 K, much higher than reported values. Our results provide a promising candidate for the development of nanothermometer with high-sensitive low-temperature sensing performance.

Temporal variations of diversity and community structure of epifauna along the latitudinal and depth gradients in China seas over nearly 60 years

To examine the diversity and community structure of epifauna along latitudinal and depth gradients in China seas and its temporal variations over nearly 60 years, a total of 61,424 records of epifauna were compiled. Latitudinal gradients of γ-diversity from 28 to 37°N showed two peaks of increase in 1958–1960; however, only one peak was observed near 28°N in 2000–2015. Along depth gradient, the peak of species richness shifted about 10 m deeper from about 50 m in 1958–1960 to about 60 m in 2000–2015. Values of α-diversity were higher in 2000–2015 than that in 1958–1960 in latitudes from 30 to 33°N and in depth from 50 to 75 m, respectively. Epifaunal communities were distributed basically along latitudinal and depth gradients. Spatial patterns of communities in the southern Yellow Sea and northern East China Sea were found relatively stable over nearly 60 years.

Geographic patterns in range sizes and their drivers of endemic angiosperms in China

AbstractGeographic range size of endemic species is the most important indicator of species' vulnerability to extinction and conservation prioritization, yet variation in range size among species and across space has been relatively understudied. We investigated the variations and geographic patterns of the range size of 9898 angiosperm species endemic to China and compared the effects of historical and contemporary climate and species' functional traits associated with dispersal ability (including growth form, fruit type, and sexual system) on range size variations. Our results revealed that narrow‐ranged endemic species are clustered in Southwest China where angiosperm species' richness peaks. Winter temperature had the strongest and negative effect on the range size of narrow‐ranged endemic species across space and species, while climate seasonality had the strongest and positive effect on the range size of wide‐ranged endemic species. Both historical and contemporary climate have also influenced species range size indirectly via their effects on species' functional traits associated with dispersal ability. Range size of all endemic species, narrow‐ranged and wide‐ranged, showed little phylogenetic signal, suggesting that phylogenetic conservatism plays a minor role in range size variations. Our results show that the range size of angiosperm species endemic to China is driven by both extrinsic spatiotemporal environmental factors and intrinsic species' traits that allow species to cope with environmental change.

Limited range shifting in biocrusts despite climate warming: A 25‐year resurvey

Abstract The ranges of many species globally have already shifted to maintain climatic equilibrium in the face of climate change. Biocrusts—soil surface dwelling communities of lichens, bryophytes and microbes—play important functional roles in many ecosystems, particularly in drylands. Compared to better studied animal and plant taxa, dryland biocrusts have different establishment requirements and have never been assessed for historical range shifts. Here, we revisited the sites (N = 204) of a 25‐year‐old biocrust survey across a large area (400,000 km2) of drylands in south‐eastern Australia. We used quadratic models to quantify changes in the climate niches of 15 lichen, eight moss and five liverwort taxa, as well as biocrust cover and richness. Our models showed that the observed climatic niches of most taxa have become hotter and drier in the past quarter century, yet the responses of the vast majority of taxa are consistent with remaining in the same geographic space. A similar pattern was observed at the community level, where the peak of biocrust cover and richness now occurs in a hotter, drier environment. Notable exceptions were the liverwort Riccia lamellosa and lichens in the genera Cladonia and Xanthoparmelia, which showed signs of contraction at their arid range edges. Unlike more mobile taxa, most biocrust species have yet to shift geographically and may already be lagging behind the pace of climate change. One explanation for the mortality lag is that long‐term climate variability in the system is extensive, which may have selected for the ability to withstand multi‐year warm periods as long as there is an eventual return to milder conditions. However, no forecasts of future climate include a return to milder conditions, suggesting there will be an eventual loss of ecosystem multifunctionality at the contracting front. Expansion lags are most likely due to delays in the mortality of competing vascular plants. Synthesis: Our study provides a valuable contribution to the knowledge of range shifts in understudied taxa and highlights a future need to promote the expansion of biocrusts to maintain the provision of ecosystem functions and services across their range.

Subterranean Fauna of the Lukina Jama–Trojama Cave System in Croatia: The Deepest Cave in the Dinaric Karst

The Dinaric Karst is a global hotspot for subterranean diversity, with two distinct peaks of species richness in the northwest and southeast, and an area of a lower species richness in the central part. In this article, we present a species list and describe the ecological conditions of the Lukina jama–Trojama cave system, located in the central part of the Dinaric Karst. This cave system is the deepest and one of the most logistically challenging cave systems sampled so far in the Dinaric Karst. Repeated sampling resulted in a list of 45 species, including 25 troglobionts, 3 troglophiles, 16 stygobionts, and 1 stygophile. Most of the recorded species are endemic to the Velebit Mountain, while three species are endemic to the Lukina jama–Trojama cave system. Within the system, species richness peaks in the deepest third of the cave, most likely reflecting the harsh ecological conditions in the upper parts, including ice, cold winds, and occasional waterfalls. Milder and more stable deeper parts of the cave contain a rich subterranean species community, part of which is associated with two very distinct aquatic habitats, the cave hygropetric and the phreatic zone. The newly recognized hotspot of subterranean biodiversity in the central Dinaric Karst, which has emerged between the two known centers of biodiversity, further highlights the species richness in large cave systems, but also challenges the diversity patterns in the Dinaric Karst overall.

Cascading effects of elephant–human interactions and the role of space and mobility in sustaining biodiversity

AbstractOur study monitored the changes in elephant numbers, distribution, and ecological impacts over a 50‐year period. During this period, the free‐ranging intermingled movements of wildlife and traditional subsistence pastoralists across the Amboseli ecosystem were disrupted by a national park, livestock ranches, farms, settlements, and changing lifestyles and economies. Elephants compressed into the national park by poaching and settlement turned woodlands to grassland and shrublands, and swamps into short grazing lawns, causing a reduction of plant and herbivore diversity and resilience to extreme events. The results echo the ecological findings of high‐density elephant populations in protected areas across eastern and southern Africa. The impact has led to the view of elephants in parks as being incompatible with biodiversity and to population control measures. In contrast to Amboseli National Park, we found woody vegetation grew and plant diversity fell in areas abandoned by elephants. We therefore used naturalistic and exclosure experiments to determine the density‐dependent response of vegetation to elephants. We found plant richness to peak at the park boundary where elephants and livestock jostled spatially, setting up a creative browsing‐grazing tension that caused a patchwork of habitats and peak of plant richness. Prehistorical and historical literature reviews lend support to the Amboseli findings that elephants and people, the two dominant keystone species in the savannas, have been intimately entangled and coexisted prior to the global ivory trade and colonialism. The findings point to the need to view specific elephant populations in historical perspective and, as far as possible, create connectivity beyond protected areas to allow mobility on an ecosystem and landscape scale. The Amboseli study underscores the significance of space and mobility in the keystone role of elephants, and community‐based conservation as a way to foster coexistence at an ecosystem and landscape scale. Space and mobility also alleviate the ecological disruption of compressed populations, and minimizes population management.

Linking different resources to recognize vascular epiphyte richness and distribution in a mountain system in southeastern Mexico

Mesoamerican mountains are important centers of endemism and diversity of epiphytes. The Sierra Madre of Chiapas in southeastern Mexico is a mountainous region of great ecological interest due to its high biological richness. We present the first checklist of epiphytes for this region based on a compilation of various information sources. In addition, we determined the conservation status for each species based on the Mexican Official Standard (NOM-059-SEMARNAT-2010), endemism based on geopolitical boundaries, spatial completeness with inventory completeness index, richness distribution with range maps, and the relationship between climatic variables (temperature and rainfall) with species richness using generalized additive models. Our dataset includes 9,799 records collected between 1896 and 2017. Our checklist includes 708 epiphytes within 160 genera and 26 families; the most species-rich family was Orchidaceae (355 species), followed by Bromeliaceae (82) and Polypodiaceae (79). There were 74 species within a category of risk and 59 species considered endemic. Completeness of epiphyte richness suggests that sampling is still largely incomplete, particularly in the lower parts of the mountain system. Species and family range maps show the highest richness at high elevations, while geographically richness increases towards the southeast. Epiphyte richness increases with increased rainfall, although a unimodal pattern was observed along the temperature gradient with a species richness peak between 16 and 20 C°. The Sierra Madre of Chiapas forms a refuge to more than 40% of all epiphytes reported for Mexico and its existing network of protected areas overlaps with the greatest epiphyte richness.

Lepidoptera Assemblages along a Western Slope Elevation Gradient of the South-Central Sierra Nevada Mountains in California

We present the results of a study of the Lepidoptera species inhabiting the various biotic zones of the western slope of the Sierra Nevada Mountains, from the Great Central Valley to the mountain crest, in an area around an approximate transect from the city of Fresno to Mono Pass. The investigation methods included day-catching, day- and nocturnal trapping, searching and rearing of immature stages, and catch and release techniques. We identified 1092 species. Most of them represented Noctuoidea, Geometroidea, Gelechioidea, Pyraloidea, and Tortricoidea superfamilies. Most species were encountered at the base of the mountain, in the Foothill Woodland zone, indicating a low-plateau pattern of species richness for our sampled area. We found a bimodal annual species richness curve at the lower elevations (Valley Floor and Foothill Woodland) with a peak in May/June and another one in October. At higher altitudes there was only one richness peak, in July. In the Valley Floor and Foothill Woodland zones there was continuous flight activity throughout the year, while at higher altitudes this activity became gradually restricted to the warmer periods of the year. Anthropogenic changes were detected in the natural habitat at all elevations. These were most pronounced in the Valley Floor and Foothill Woodland zones, thereafter decreasing with the altitude. We found a direct relationship between the mean low temperature values in any given zone and month and the number of species flying at that time and altitude. We assessed this relationship visually, from the charts we plotted for each zone with the pertinent values. During this study, we encountered larval-host plant associations for Udea vacunalis (Pyralidae), Anoncia mosa (Cosmopterygidae), and Aristotelia sp. (Gelechiidae) for which we could not find any references in the literature as well as certain larval habits of Plebejus acmon and Agriades podarce (both Lycaenidae) that expand the awareness concerning their larval behaviors.

Seasonal beta‐diversity of dry grassland vegetation: Divergent peaks of above‐ground biomass and species richness

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

Liverworts show a globally consistent mid-elevation richness peak.

The study of elevational gradients allows to draw conclusions on the factors and mechanisms determining patterns in species richness distribution. Several earlier studies investigated liverwort diversity on single or few elevational transects. However, a comprehensive survey of the elevational distribution patterns of liverwort richness and their underlying factors is lacking so far. This study's purpose was to fill this gap by compiling an extensive data set of liverwort elevational patterns encompassing a broad diversity of mountains and mountain ranges around the world. Using polynomial regression analyses, we found a prevalence of hump-shaped richness patterns (19 of 25 gradients), where liverwort species richness peaked at mid-elevation and decreased towards both ends of the gradient. Against our expectation and unlike in other plant groups, in liverworts, this pattern also applies to elevational gradients at mid-latitudes in temperate climates. Indeed, relative elevation, calculated as the percentage of the elevational range potentially inhabited by liverworts, was the most powerful predictor for the distribution of liverwort species richness. We conclude from these results that the admixture of low- and high-elevation liverwort floras, in combination with steep ecological gradients, leads to a mid-elevation floristic turnover shaping elevational patterns of liverwort diversity. Our analyses further detected significant effects of climatic variables (temperature of the warmest month, potential evapotranspiration, and precipitation of the warmest month) in explaining elevational liverwort richness patterns. This indicates that montane liverwort diversity is restricted by high temperatures and subsequent low water availability especially towards lower elevations, which presumably will lead to serious effects by temperature shifts associated with global warming.