Patterns Of Species Diversity Research Articles

A global assessment of species diversification in aquaculture

Aquaculture is a diverse food production system, and a high species diversity in aquaculture can make the global food system more resilient. Species diversification could facilitate aquaculture growth through multiple mechanisms and increase the sector's resilience and long-term sustainability. Facing increasing challenges from climate change, disease outbreaks, market fluctuations, and other disturbances, species diversification has become a widely recognized and endorsed development strategy in the policy and scientific communities for the growth and resilience of the aquaculture sector. However, many attempts to establish new species have yielded little long-term success, and the private sector often concentrates efforts on the most advantageous species for rapid growth. This paper presents a comprehensive assessment of aquaculture species diversification at the global, regional (more than 30 country groups), and national (nearly 200 countries) levels, covering the period 1950 to 2020 with a focus on 1990 to 2020. The assessment employs the concept of “effective number of species” as a measure of diversity and uses two sub-indicators to assess within-group versus between-group diversity. The indicator system reveals detailed patterns of species diversity and uncovers different driving forces of species diversification. Additionally, the study maps the status and trends of species diversity to offer a refined perspective on species diversity profiles and diversification patterns. The findings reveal that beneath high species diversity in world aquaculture lies generally low diversity at the national level; nearly half of national aquaculture has no within-group or between-group diversity. Furthermore, species diversification has been losing momentum in recent decades, and concentration has become a more prominent development pathway, with a tendency to drive aquaculture towards a low-diversity system similar to terrestrial farming. Public interventions are crucial to promote species diversification in aquaculture for the sector's resilience and long-term sustainability. It is important to not only reduce the cost of species diversification for the private sector but also to dedicate more public efforts towards increasing its benefits and viability. While diverse diversification patterns among national aquaculture indicate no one-style-fits-all species diversification pathway, a country may draw guidance from others' experiences, especially since countries with similar species diversity profiles or diversification patterns tend to cluster geographically. Evidence-based policymaking and sector management regarding species diversification entail collaborative efforts among policymakers, scientists, and the aquaculture community to expand and refine assessment frameworks, improve data availability and quality, and efficiently utilize information, knowledge, and insights generated by these assessments to inform decision making at various levels.

RETRACTED: A primer of community ecology using the R language

AbstractCommunity ecology beginners often struggle to understand theories expressed in complex mathematical formulas and to master computer programming. To remedy this situation, this article provides a practical, R‐based introduction to community ecology by illustrating core concepts (vital rates, carrying capacity, and density dependence) and models that can be used to explore the patterns of species abundance and diversity. The structure of this article consists of three modeling exercises, each asking a general question that can be answered by a combination of theory and R programming: (1) what determines the abundance of species, and what makes a population persist and go extinct?; (2) what determines the distribution of species and species diversity?; (3) what determines the relative abundance of species and what allows species to coexist? Through the exercises, I discuss the following five concepts and ideas that provide valuable insights into the questions: (i) the tragedy of the commons, (ii) the theory of island biogeography, (iii) competitive exclusion, (iv) the neutral theory of biodiversity, and (v) frequency dependence. These materials are thus designed to guide the reader in developing an intuition for ecological thinking that will help capture the essence of the global environmental and biodiversity crisis. Although this article does not delineate the scope and depth of the vast field of community ecology, I hope that it will motivate the reader to step up to a more formal introduction to community ecology.

Climatic niche evolution in Smilacaceae (Liliales) drives patterns of species diversification and richness between the Old and New World

AbstractGeographical variation in species richness in plant groups is determined by the interplay between historical, evolutionary, and ecological processes. However, the processes underlying the striking disparity in species richness between Asia and the Americas remain poorly understood. Here, we synthesize global phylogenetic and macroecological data on the diversification of Smilacaceae, deciphering potential drivers underlying the species diversity pattern biased toward Asia. We compiled global distributions of all Smilacaceae species, and reconstructed the biogeographic history and niche evolution using a new time‐calibrated phylogeny (eight genes, 135 species). Integrating these data sets, we estimated evolutionary histories and diversification rates for each region, and tested correlations among species diversification, niche evolution, and niche divergence. Smilacaceae probably originated during the Late Cretaceous/Early Palaeocene and began to diversify in middle to low latitudes in Central America and Eurasia during the Late Eocene. Both the Old and New World clades exhibited a steady, albeit slight, increase of species diversification from the Late Eocene to Early Miocene. However, the Old World clade experienced an abrupt increase in net diversification during the Late Miocene. Our findings also revealed that species diversification rates were positively correlated with ecological niche evolution and niche divergence. Niche shifts and climatic niche evolution since the Middle Miocene played crucial roles in species diversification dynamics within Smilacaceae. The high plant richness in Asia may be explained by greater diversification in this region, potentially promoted by heterogeneous environments.

Genomic and species diversity patterns across multiple trophic levels in riverscapes

Testing whether intra‐ and interspecific biodiversity facets co‐vary spatially across trophic levels is of utmost importance to generalize processes driving biodiversity patterns in natural landscapes. Similar processes are expected to act on intra‐ and interspecific diversity, which should lead to positive co‐variation between genetic and species diversity. Although this prediction has been verified within trophic levels, it has rarely been tested across multiple trophic levels. To meet this challenge, we focused on a riverine freshwater ecosystem in which we sampled intra‐ (genomic diversity) and interspecific (species diversity) data across three trophic levels: riparian trees, benthic macroinvertebrates and fishes. For each trophic level, we quantified α‐ and β‐diversity at both the intra‐ (SNP diversity within populations of Alnus glutinosa, Gammarus sp. or Phoxinus dragarum) and interspecific levels (species diversity within communities). We first tested for a global spatial co‐variation of diversity across trophic levels and diversity facets. We then tested whether relevant environmental parameters similarly affected each biodiversity estimate and explained potential spatial co‐variation among biodiversity components. We did not evidence any spatial co‐variation of biodiversity across trophic levels and diversity facets, neither for α‐ nor for β‐diversity. We found that sites situated in the Western part of the sampling area had higher α‐diversities, and that highly connected sites had lower β‐diversities, which holds true for all trophic levels and diversity facets. Nonetheless, the effects of other environmental predictors were specific to each biodiversity component, likely explaining the absence of spatial co‐variation among biodiversity components. Our study demonstrates that global biodiversity patterns in rivers can be hard to generalize and are rather idiosyncratic, even though a few processes might have consistent impacts on biodiversity components across trophic levels.

Geographical patterns and drivers of plant productivity and species diversity in the Qinghai-Tibet Plateau

The Qinghai-Tibet Plateau (QTP) has three main grassland types: alpine meadow, alpine steppe, and alpine desert steppe. In this study, we asked how plant productivity and species diversity vary with altitude, longitude and latitude in alpine grasslands of the QTP. We then identified the environmental factors that drive these observed patterns of plant productivity and species diversity. We found that although plant productivity and species diversity varied greatly across large-scale longitudinal and latitudinal gradients, these changes were strongest across the longitudinal gradient. This finding indicates that moisture rather than temperature has the greatest impact on plant productivity and species diversity of the alpine grasslands in the QTP. We also found that besides soil and climate factors, partial pressure of carbon dioxide (pCO2) also has significant effects on plant productivity, and barometric pressure and partial pressure of oxygen (pO2) also have significant effects on species diversity. Furthermore, the relationship between the biomass of grassland-dominant species and species diversity was affected by the spatial scale at which these factors were studied. Our study provides new insights into the interconnections between plant productivity and species diversity and the major factors that influence alpine grasslands. It also provides a scientific basis for the maintenance of plant diversity and ecosystem functions in hypoxic (low-oxygen) regions.

Woody debris structures on large clearcut openings: Oases for small mustelids and prey species?

Restoration structures such as post-harvest woody debris piles on large clearcut openings may provide habitat for many mammal species. Mustelids such as the American marten (Martes americana) and several weasel (Mustela spp.) species are important furbearers in temperate and boreal forests and are negatively affected by clearcutting. We ask if constructed piles of woody debris on large (e.g., 30–50 ha) openings will be used by these mustelids and their small mammal prey species? We tested the hypotheses (H) that (H1) the presence (index of activity patterns) of small mustelids, (H2) abundance, species richness, and species diversity of the forest-floor small mammal community, and (H3) reproduction of the major species: southern red-backed vole (Clethrionomys gapperi), long-tailed vole (Microtus longicaudus), and deer mouse (Peromyscus maniculatus), would be greater on sites with woody debris piles than on sites with dispersed debris. A fourth hypothesis (H4) predicted that the above response variables would be similar across a linear configuration of debris piles on the large openings. Mustelid presence and populations of forest-floor small mammals were sampled on four replicated (n = 4) large (30–50 ha) clearcut sites from 2017 to 2022 in south-central British Columbia, Canada.Mean presence of mustelids was significantly higher (4.5 to 8.0 times) in piles than dispersed sites during the first four post-harvest years, thereby supporting H1. Mean index of mustelid activity per line was similar among pile index-lines across these clearcut openings. Mean abundance of C. gapperi was similar statistically between treatment sites but with numbers 3 to 10 times higher, on average, in the piles than dispersed sites and was likely biologically important. Mean abundance of M. longicaudus was significantly higher (1.2–4.4 times) in the piles than dispersed sites. Mean abundance of P. maniculatus and Sorex spp. were similar between treatment sites. Mean abundance of total small mammals, including the less common species, was significantly higher (1.4–1.9 times) in piles than dispersed sites. Similarly, mean species richness and diversity were both significantly higher in piles than dispersed sites. Mean number of total recruits was higher in piles than dispersed sites for M. longicaudus and P. maniculatus, but most measures of reproductive attributes were similar, thereby providing only partial support for H3. As per support for H4, response variables were similar across a linear array of debris piles on large openings. Our study is the first to measure responses of small mustelids and forest-floor small mammals to constructed piles of woody debris as a means of habitat restoration on relatively large (mean area 40.5 ha) openings created by conventional clearcutting. Piles of debris seem to act as oases for mustelids and their prey species in ecological restoration of cutover forest land.

Species assemblages of insular Caribbean Sticta (lichenized Ascomycota: Peltigerales) over ecological and evolutionary time scales

Phylogenetic approaches to macroevolution have provided unique insight into evolutionary relationships, ancestral ranges, and diversification patterns for many taxa. Similar frameworks have also been developed to assess how environmental and/or spatial variables shape species diversity and distribution patterns at different spatial/temporal scales, but studies implementing these are still scarce for many groups, including lichens. Here, we combine phylogeny-based ancestral range reconstruction and diversification analysis with community phylogenetics to reconstruct evolutionary origins and assess patterns of taxonomic and phylogenetic relatedness between island communities of the lichenized fungal genus Sticta in the Caribbean. Sampling was carried out in the Greater Antilles (Cuba, Jamaica, Dominican Republic, and Puerto Rico) and Lesser Antilles (Dominica, Guadeloupe, and Martinique). Data for six molecular loci were obtained for 64 candidate Caribbean species and used to perform both macroevolutionary phylogenetics, which also included worldwide taxa, and phylobetadiversity analyses, which emphasized island-level communities. Our work uncovered high levels of island endemism (∼59%) in Caribbean Sticta. We estimate initial colonization of the region occurred about 19 Mya from a South American ancestor. Reverse migration events by Caribbean lineages to South America were also inferred. We found no evidence for increased diversification rates associated with range expansion into the Caribbean. Taxonomic and phylogenetic turnover between island-level communities was most strongly correlated with environmental variation rather than with geographic distance. We observed less dissimilarity among communities from the Dominican Republic and Jamaica than between these islands and the Lesser Antilles/Puerto Rico. High levels of hidden diversity and endemism in Caribbean Sticta reaffirm that islands are crucial for the maintenance of global biodiversity of lichenized fungi. Altogether, our findings suggest that strong evolutionary links exist between Caribbean and South American biotas but at regional scales, species assemblages exhibit complex taxonomic and phylogenetic relationships that are determined by local environments and shared evolutionary histories.

New distribution record of the Greater False Vampire Bat (Megaderma lyra, Geoffroy 1810) from North-Western Himalaya

India has been stated to have 10% of the world's total bat's diversity. The present survey was aimed to study the bat species diversity, distribution and activity patterns in north-western Himalayan region of India. Field surveys were conducted and echolocation calls were recorded using bat detector, Echometer touch 2 in Shiwalik ranges of Himalaya. The Greater False Vampire Bat (Megaderma lyra) has a broad distribution range that stretches from south to south east Asia. In India the distribution of the species was mostly recorded from southern subtropical coastal regions and north-eastern subtropical moist evergreen forests. In the present study The Greater False Vampire Bat (Megaderma lyra) has been recorded for the first time from Garhwal region of north-western Himalayas. Greater False Vampire Bat (Megaderma lyra) having long forearm (>6.63 ± 0.03cm) and lengthy ear (>3.66 ± 0.08cm), which is a distinguishable feature of the family Megadermatidae. The peak frequency (FMaxE) of echolocation was recorded as 50.295 ± 9.18 kHz. This frequency was initiated at 108.20 ± 2.51 kHz and terminated at 30.76 ± 1.37 kHz. The call structure recorded was very distinguishable and specific to this family.

Checklist of national key protected wild plants on the Qinghai-Tibetan Plateau.

Qinghai-Tibetan Plateau is a global biodiversity hotspot due to the unique geographical environment. However, there are few reports on the list of national key protected plants and the distribution pattern of their diversity in this area. Based on the flora and online database, this paper summarised the species diversity and distribution patterns of national key protected wild plants on the Qinghai-Tibet Plateau. The results showed that there were 350 species of national key protected wild plants on the Qinghai-Tibetan Plateau, belonging to 72 families and 130 genera. Amongst them, 22 species were under class I protection, 328 species were under class II protection and 168 species were endemic to China. Its endangered status involves EW 1 species, CR 17 species, EN 90 species, VU 90 species, NT 30 species, LC 60 species and DD 62 species. Species diversity declined gradually from the southeast to the northwest with hotspots located within Sanjiang Valley subregion (ⅢE14a). The list of national key protected wild plants and their diversity and distribution patterns in the Qinghai-Tibetan Plateau can provide basic data for the conservation of regional biodiversity and the formulation of conservation strategies.

Plant diversity patterns along an elevation gradient: the relative impact of environmental and spatial variation on plant diversity and assembly in arid and semi-arid regions

The spatial distribution pattern of species diversity and its driving variables are essential to understanding how biodiversity will respond to the threat of future climatic instability. This study examines how the alpha and beta diversity indices vary along the elevation gradient and which factors are more responsible for arid and semi-arid plant diversity and community assembly. There were 121 species from 90 genera and 42 families found at elevations ranging from 1,200 to 2,600 m within the Ningxia Helan Mountain National Nature Reserve in China. These were primarily shrubs and herbs with characteristics adapted to extreme temperatures. The diversity of both the shrub layer and the herb layer was highest at mid-elevation, underscoring the importance of protecting mid-elevation ecosystems. Climatic distance and topographic distance were more influential than spatial distance in driving the species composition change of shrubs and herbs. In the herb layer, climatic, topographic, and spatial factors contributed more to community assembly than shrub communities. In this case, improving the environment in the community or introducing herbs could help the restoration of these places. These findings provide insight into biogeographic patterns, biodiversity growth mechanisms, and community formation processes. Moreover, it can improve projections of climate change within and across ecosystems and provide the scientific basis for the use and management of plant resources in arid and semi-arid regions.

Responses of arid plant species diversity and composition to environmental factors

An oasis is a unique natural landscape in arid and semi-arid areas, significant for regulating regional microclimates and hydrological processes in deserts. However, little is known regarding the response of natural oasis plants communities to various environmental factors. Nineteen sample plots (50 m × 50 m) were selected in the Daliyabuyi Oasis in the Taklimakan Desert hinterland based on the location of groundwater monitoring wells and 76 vegetation quadrats (25 m × 25 m) were established. A two-way indicator species analysis, Mantel test, detrended correspondence analysis, canonical correspondence analysis (CCA), and hierarchical partitioning were used to provide an in-depth analysis of community classification, species composition, and environmental interpretation of the oasis. A generalized linear model was used to verify the results which showed that the current oasis community could be divided into four types according to the dominant species, which is controlled by soil moisture. Measurement of species composition and distribution of communities showed significant differences between species diversity of individual community types. Variations in groundwater depth affects patterns of species diversity which is sensitive to richness, while the degree of surface water disturbance affects the pattern of species evenness. Moreover, the CCA ordination map showed that community distribution and diversity characteristics have their own preferences in habitat gradients. The study concluded that the species dominance of the community and the composition and distribution are not dominated by a single factor. There are differences in the scale and effect of different water resource types in maintaining community characteristics.

Relationship between species diversity and tree size in natural forests around the Tropic of Cancer

Although numerous hypotheses have been proposed to explain the patterns of species diversity of forests at local and landscape levels, it is still difficult to predict the alpha diversity of species, especially in tropical and subtropical natural forests where trees of different sizes and shapes are highly mixed. Size might characterize species diversity, and the possible correlation between these variables may contribute to the development of easy-to-use growth indicators to predict diversity and to understand the status of trees within a stand. In this study, diameter classes were divided using the equal diameter class (EDC) and minimum measured diameter (MMD) methods, and five species diversity indices were calculated for each diameter class of 14 permanent plots in five national nature reserves surrounding the Tropic of Cancer (23.5°), southwest China. The results show that species richness, abundance, and spatial diversity indices decreased in a typical inverted J-shape pattern with increasing diameter class and MMD, and could be easily modeled by a negative exponential function. The Shannon–Wiener index showed a linear decrease while Pielou’s evenness index displayed a linear increase, with a small degree of instability. The results suggest that species diversity in subtropical forests is closely related to tree size, and the relationship is possibly independent of habitat. Measuring DBH of some trees in a stand could be informative regarding species diversity and contribute to the investigation and assessment of biodiversity.

Spatial patterns, underlying drivers and conservation priorities of orchids in the central Himalaya

Understanding the primary drivers of species diversity patterns and identifying critical places for biodiversity protection are the two major concerns confronting the global conservation community. The Orchidaceae, which is one of the most diverse angiosperm families with over 30,000 species, is currently facing grave threats from habitat degradation, climate change, and a range of human-induced issues. However, the spatial patterns of orchid distribution and the factors influencing these patterns, both of which are crucial for developing successful orchid conservation plans, remain poorly understood. Here, using one of the most extensive distribution datasets of >500 orchid species in Nepal, we mapped the distribution of all, common, rare, epiphyte, and terrestrial species and identified important factors driving their patterns. We also assessed their protection gaps and identified key conservation regions. We discovered low spatial congruence between the diversity patterns of different groups, and the fundamental drivers underlying the richness pattern differed considerably. The key orchid conservation areas were primarily found in the mid-hills and highlands of central Nepal, with 62 % of these areas outside the protected area (PA) network. Our findings emphasize the importance of considering pollinator diversity and other climate factors when developing effective management plans to conserve orchids, as well as employing different strategies to conserve different life forms. A huge conservation gap in protecting orchids despite large PA coverage in Nepal indicates insufficiency of existing PA network in conserving plants. Therefore, our findings reiterates the need to consider plant conservation goals alongside animal conservation priorities in future conservation planning.

Can cities provide butterfly-friendly habitats?

Abstract. Winarni NL, Nuruliawati, Anugra BG, Junaid AR, Widayanti S, Aslan, Nugroho A, Miga I, Kurniawan MB, Liestanti M, Lutfiani RA, Wulandari Y. 2023. Can cities provide butterfly-friendly habitats? Biodiversitas 24: 2334-2341. Cities are progressively changed over time, creating land use changes with reduced green space areas. On the other hand, urban habitats offer a range of opportunities for biodiversity including butterflies which also act as an ecological health indicator. In Indonesia, like Jakarta Greater Area, or the so-called Jabodetabek which comprised Jakarta and its satellite cities, Bogor, Depok, Tangerang, and Bekasi, is highly urbanized. However, its capabilities to support the butterfly community are still little known. Thus, this paper aims to identify Jakarta Greater Area’s potential as urban habitat for butterflies through a citizen science approach namely KupuKita. The data were collected from June 2021 to November 2022. The survey used KupuKita platform, an online questionnaire established in 2021, which focused on three families, Nymphalidae, Papilionidae, and Pieridae. Its species richness, diversity and community pattern were analyzed consecutively by using Shannon-Wiener and Simpson’s Index. Next, the results were also analyzed towards the vegetation strata (grasses, shrubs, and trees) as observed during the data collection. The results suggested that Jakarta, Tangerang, and Bekasi have the least diverse butterfly community in comparison to Depok and Bogor. The butterfly community in Depok and Bogor was similar, both high in richness and diversity. Such similarity was potentially due to the wide arrays of remaining habitats that supported butterfly communities in three strata. The shrubs support more species richness rather than other strata. Bogor and Depok were potentially support more species in all three strata. Hence, because of the closely plant-butterfly relationships, vegetation interventions are crucial to increase the complexity of vegetation and create a butterfly-friendly habitat.

The contribution of common and rare species to species abundance patterns in alpine meadows: The effect of elevation gradients

Ecological niche modeling uses environmental variables associated with species distribution points to simulate species distribution and its importance in biodiversity conservation. This study aimed to quantify plant community composition and species abundance distribution (SAD) in alpine meadows at different elevations and to assess the contribution of rare and common species to SAD. We established a permanent study plot of 210 hm2 in Gannan Tibetan Autonomous Prefecture, China, surveyed 315 sample squares (0.5 m × 0.5 m), and calculated the Hill numbers. The results showed that (1) a total of 72 species were surveyed at different altitudes, with Kobresia humilis and Kobresia macrantha as the main dominant species; (2) the SADs of overall and common species fit the ecological niche model (GSM (Geometric Sequence Model)), indicating that ecological niche differentiation is the main factor influencing SAD. The fitted model for rare species SAD varied with elevation, suggesting that various ecological processes influence rare species SAD. (3) Hill numbers showed a “single peak” pattern with increasing elevation. The number of rare species was higher than that of common species. Still, the distribution frequency of common species was significantly higher than rare species. The correlation between common-rare species sequences and cumulative species distribution was high. This indicates that common species dominate the species diversity pattern of the community, are the main contributors to the SAD pattern, and should be protected first. Rare species are also important carriers of community function and include much spatial information. Rare and common species work together in different ways to influence and maintain the species diversity patterns of alpine meadow plant communities.

Mapping tree species diversity in temperate montane forests using Sentinel-1 and Sentinel-2 imagery and topography data

Detailed information on spatial patterns of tree species diversity (TSD) is essential for biodiversity assessment, forest disturbance monitoring, and the management and conservation of forest resources. TSD mapping approaches based on the Spectral Variability Hypothesis (SVH) could provide a reliable alternative to image classification methods. However, such methods have not been tested in large-scale TSD mapping using Sentinel-1 and Sentinel-2 images. In this study, we developed a new workflow for large-scale TSD mapping in an approximately 4000 km2 temperate montane forest using Sentinel-1 and Sentinel-2 imagery-based heterogeneity metrics and topographic data. Through a systematic comparison of model performance in 24 prediction scenarios with different combinations of input variables, and a correlation analysis between six image heterogeneity metrics and two in-situ TSD indicators (species richness S and Shannon-Wiener diversity H′), we assessed the effects of vegetation phenology, image heterogeneity metrics, and sensor type on the accuracy of TSD predictions. Our results show that (1) the combination of Sentinel-1 and Sentinel-2 imagery produced higher accuracy of TSD predictions compared to the Sentinel-2 data alone, and that the further inclusion of topographic data yielded the highest accuracy (S: R2 = 0.562, RMSE = 1.502; H′: R2 = 0.628, RMSE = 0.231); (2) both Multi-Temporal and Spectral-Temporal-Metric data capture phenology-related information of tree species and significantly improved the accuracy of TSD predictions; (3) texture metrics outperformed other image heterogeneity metrics (i.e., Coefficient of Variation, Rao's Q, Convex Hull Volume, Spectral Angle Mapper, and the Convex Hull Area), and the enhanced vegetation index (EVI) derived image heterogeneity metrics were most effective in predicting TSD; and (4) the spatial distribution of TSD showed a clear decrease trend along the altitudinal gradient (r = −0.61 for S and − 0.45 for H′) and varied significantly among forest types. Our results suggest a good potential of the SVH-based approaches combined with Sentinel-1 and Sentinel-2 imagery and topographic data for large-scale TSD mapping in temperate montane forests. The TSD maps generated in our study will be valuable for forest biodiversity assessments and for developing management and conservation measures.

Relationship between plant species diversity and aboveground biomass in alpine grasslands on the Qinghai–Tibet Plateau: Spatial patterns and the factors driving them

Alpine grasslands are important ecosystems on the Qinghai–Tibet Plateau and are extremely sensitive to climate change. However, the spatial responses of plant species diversity and biomass in alpine grasslands to environmental factors under the background of global climate change have not been thoroughly characterized. In this study, a random forest model was constructed using grassland ground monitoring data with satellite remote sensing data and environmental variables to characterize the plant species diversity and aboveground biomass of grasslands in the Three-River Headwaters Region within the Qinghai–Tibet Plateau and analyze spatial variation in the relationship between the plant species diversity and aboveground biomass and their driving factors. The results show that (1) the selection of characteristic variables can effectively improve the accuracy of random forest models. The stepwise regression variable selection method was the most effective approach, with an R2 of 0.60 for the plant species diversity prediction model and 0.55 for the aboveground biomass prediction model, (2) The spatial distribution patterns of the plant species diversity and aboveground biomass in the study area were similar, they were both high in the southeast and low in the northwest and gradually decreased from east to west. The relationship between the plant species diversity and aboveground biomass varied spatially, they were mostly positively correlated (67.63%), but they were negatively correlated in areas with low and high values of plant species diversity and aboveground biomass, and (3) Analysis with geodetector revealed that longitude, average annual precipitation, and elevation were the main factors driving variation in the plant species diversity and aboveground biomass relationship. We characterized plant species diversity and aboveground biomass, as well as their spatial relationships, over a large spatial scale. Our data will aid biodiversity monitoring and grassland conservation management, as well as future studies aimed at clarifying the relationship between biodiversity and ecosystem functions.

Evolutionary history and global angiosperm species richness–climate relationships

AbstractAimClimate has been regarded as an important explanation for large‐scale species richness patterns. However, the mechanisms underlying the significant variations in species richness–climate relationships across different clades remain to be tested. We explored how niche conservatism, diversification rates and time for speciation influenced species richness–climate relationships between clades.LocationThe globe.Time PeriodPresent day.Major Taxa StudiedAngiosperms.MethodsBased on a newly complied database of the global distributions of 288,735 angiosperm species, we used generalized linear models to assess the relationships between species richness of different angiosperm families and climatic factors. We also conducted phylogenetic comparative analysis to test whether niche conservatism, diversification rates and time for speciation affect the variations in species richness–climate relationships.ResultsWe found that temperature seasonality dominated the global angiosperm diversity patterns. Closely related families had more similar species richness–climate relationships than distantly related ones. The discrepancy between the current and ancestral niches of different clades had much stronger effects on variations in species richness–climate relationships than diversification rates and time for speciation. With the increase in the discrepancy between current and ancestral niches, the explanatory power (i.e., R2) of contemporary temperature and precipitation in explaining species richness patterns increased.Main ConclusionsOverall, our findings strongly support that niche conservatism dominates the variations in species richness–climate relationships across taxonomic groups. These findings allow better understanding on how large‐scale species diversity patterns are formed.

The impact of traditional conservation practices on species composition and diversity patterns of sacred swamps in the central Western Ghats, India

The impact of traditional conservation practices on species composition and diversity patterns of sacred swamps in the central Western Ghats, India

A clue to the evolutionary history of modern East Asian flora: Insights from phylogeography and diterpenoid alkaloid distribution pattern of the Spiraea japonica complex

Each subkingdom of East Asian flora (EAF) has a unique evolutionary history, but which has rarely been described based on phylogeographic studies of EAF species. The Spiraea japonica L. complex, which is widespread in East Asia (EA), has received considerable attention because of the presence of diterpenoid alkaloids (DAs). It provides a proxy for understanding the genetic diversity and DA distribution patterns of species under various environmental conditions associated with the geological background in EA. In the present study, the plastome and chloroplast/nuclear DNA of 71 populations belonging to the S. japonica complex and its congeners were sequenced, combined with DA identification, environmental analyses, and ecological niche modelling, to investigate their phylogenetic relationships, genetic and DAs distribution patterns, biogeography, and demographic dynamics. An “ampliative” S. japonica complex was put forward, comprising all species of Sect. Calospira Ser. Japonicae, of which three evolutionary units carrying their respective unique types of DAs were identified and associated with the regionalization of EAF (referring to the Hengduan Mountains, central China, and east China). Moreover, a transition belt in central China with its biogeographic significance was revealed by genetic and DA distribution patterns from the perspective of ecological adaptation. The origin and onset differentiation of the “ampliative” S. japonica complex was estimated in the early Miocene (22.01/19.44 Ma). The formation of Japanese populations (6.75 Ma) was facilitated by the land bridge, which subsequently had a fairly stable demographic history. The populations in east China have undergone a founder effect after the Last Glacial Maximum, which may have been promoted by the expansion potential of polyploidization. Overall, the in-situ origin and diversification of the “ampliative” S. japonica complex since the early Miocene is a vertical section of the formation and development of modern EAF and was shaped by the geological history of each subkingdom.