Plant functional types and climatic change: Introduction

Abstract. Plant functional types are a necessary device for reducing the complex and often uncharted characteristics of species diversity in function and structure when attempting to project the nature and function of species assemblages into future environments. A workshop was held to review the current methods commonly used for defining plant functional types, either globally or for particular biomes, and to compare them with the field experiences of specialists for specific biomes of the world. The methods fall into either an objective and inductive approach or a subjective and deductive approach. When the different methods were tested, it was generally found that the classification for one site or environment was not wholly applicable to a different site or environment. However, the degree of change which is necessary for adjustment between environments may not prove to be a major limitation in the use of functional types.     

9. The algal flora of the Primorsky Region, Russian Far East

A survey of the freshwater algal flora of the Primorsky Region, Russian Far East, is presented. During more than 70 years of investigations 1659 species (including varieties and forms 2276 taxa) belonging to 346 genera of different groups of algae have been recorded from this territory. The Primorsky Region is rich in habitats attractive to algae-rivers, lakes, reservoirs, and ponds. The details of the distribution of algae in different types of waterbodies have been examined. The algal flora of the region is comparable to the areas, and its taxonomical structure is typical for Eurasia. From this territory some new species and varieties have been described — Achnanthes chankensis, Cymbella ventricosa var. hankensis, Surirella alisoviana, and others. The flora includes some rare species — Fragilaria magocsyi, Perone dimorpha, and Heterothrix monochloron, and some endemics of Asia — Navicula scutelloides var. baicalensis, N. globulifera var. nipponica, Gomphonema sphaerophorum, and Surirella tientsinensis.     

Developing and testing alien species indicators for Europe

Alien species indicators provide vital information to the biodiversity policy sector on the status-quo and trends of biological invasions and on the efficacy of response measures. Applicable at different geographical scales and organizational levels, alien species indicators struggle with data availability and quality. Based on policy needs and previous work on the global scale, we here present a set of six alien species indicators for Europe, which capture complementary facets of biological invasions in Europe: (a) an combined index of invasion trends, (b) an indicator on pathways of invasions, (c) the Red List Index of Invasive Alien Species (IAS), (d) an indicator of IAS impacts on ecosystem services, (e) trends in incidence of livestock diseases and (f) an indicator on costs for alien species management and research. Each of these indicators has its particular strengths and shortcomings, but combined they allow for a nuanced understanding of the status and trends of biological invasions in Europe. We found that the scale and impact of biological invasions are steadily increasing across all impact indicators, although societal response in recent years has increased. The Red List Index is fit-for-purpose and demonstrates that overall extinction risks (here shown for amphibians in Europe) are increasing. Introduction pathway dynamics have changed, with some pathways decreasing in relevance (e.g., biological control agents) and others increasing (e.g., horticultural trade) providing a leverage for targeted policy and stakeholder response. The IAS indicators presented here for the first time on a continental basis serve as a starting point for future improvements, and as a basis for monitoring the efficacy of the recent EU legislation of IAS. This will need a better workflow for data collection and management. To achieve this, all main actors must work toward improving the interoperability among existing databases and between data holders.     

Stable isotope proxies for evaluating biodiversity in stream biota

Differences in δ¹³C and δ¹⁵N values in stream biota are caused by several environmental conditions. Variations in abundance, species richness and the assemblage structure of stream biota are also caused by several environmental conditions. Hence, abundance, species richness and the assemblage structure of stream biota are expected to be strongly correlated with the differences in value of stable isotopes. In this study, the gaps in δ¹³C and δ¹⁵N between periphyton and charr are discussed in terms of the abundance, genus richness, and assemblage of benthic invertebrates at each site. Gaps in δ¹³C between periphyton and charr were strongly correlated with some aspects of mountainous area and the genus richness of benthic invertebrates at each site. The gaps in δ¹⁵N between periphyton and charr were strongly correlated with the abundance and assemblage structure of benthic invertebrates at the location tested. The δ¹³C values of predators were correlated with some aspects of mountainous area and the assemblage structure of the benthic invertebrates. The δ¹⁵N values of predators were correlated with genus richness and the assemblage structure of the benthic invertebrates. These results suggest that the value gaps in δ¹³C and δ¹⁵N can be used to assess biodiversity and could provide indices for estimating the biodiversity in a stream.     

Why is biodiversity data-deficiency an ongoing conservation dilemma in Africa?

Recent reports illustrate deficiencies in knowledge about current conditions and long-term trends in population sizes of hundreds of African plants and animals’ species. In this commentary, I discuss the lack of standardized data for assessing and monitoring biodiversity in Africa. I present my own views on the causes for these knowledge and data gaps, their consequences for conservation, and future directions that could improve the current situation.There are many reasons for lack of standardized data including; ongoing conflicts and political instability in many biodiversity-rich countries; absence of regular and policy-driven monitoring programs; weak facilities; and irregular or insufficient funding. Existing biodiversity monitoring initiatives are often short-term, poorly-designed surveys, largely dependent on volunteer researchers or international partners, biased towards large “charismatic” animal species, and published in difficult-to-access outlets. Consequently, up-to-date and rigorous reports about conditions and trends of African biodiversity are limited, and conservation planning, comparative studies and accurate valuation of ecosystem services continue to be difficult.Urgent actions include: 1) commitments and support of local governments to implement effective conservation monitoring programs; 2) establishment of a network of carefully designed long-term and continent-wide monitoring initiatives for endangered species and biodiversity; and 3) involvement of universities, research centers, Non-Governmental Organizations (NGOs) and local communities in such monitoring efforts. Such actions could stimulate further in-depth studies and systematic analysis of the root causes and solutions for the decades-long African biodiversity knowledge gap. Examples of highly needed systematic analysis and documentation in the coming efforts towards filling up the biodiversity data gap in Africa should clearly define biodiversity data-deficiency by taxonomic groups and by countries.     

From phylogenetic to functional originality: Guide through indices and new developments

In biodiversity studies a species is often classified as original when it has few closely related species, a definition that reflects its phylogenetic originality. More recently, studies have focussed on biological or functional traits that reflect the role(s) that species play within communities and ecosystems. This has led many studies to an alternative evaluation of species’ originality: its functional originality. Most indices of species' originality were developed to treat the hierarchical structure of a (phylogenetic) tree. The change in perspective from measures of phylogenetic originality to measures of functional originality thus raises methodological issues particularly around the need to develop indices explicitly appropriate for evaluating functional trait-based originality. We compare indices of species' originality including a new index which we develop to evaluate (1) whether phylogenetic originality could serve as a proxy for functional originality in conservation and ecological studies; (2) whether the transformation of functional data into functional trees modifies the way species are ranked according to their originality measures compared to approaches that directly rely on pairwise functional dissimilarities among species; and more generally, (3) whether different indices provide different views on how original species are from each other, hence reflecting different ecological and evolutionary processes that generated patterns of originality. Using simulations and a real case study, we show that: (1) the strong effects of the choice of a clustering approach can affect reported levels of dissimilarities among species; (2) the tree-based approaches could better reflect the trait-generating processes under constant (Brownian) rates of evolution; and (3) phylogenetic originality measures can depart from functional originality measures when species have large amount of independent evolution. Overall, phylogenies may be used at large scales but cannot replace functional approaches designed for depicting community assembly. Indeed, traits involved in ecological processes may have various histories and thus moderate phylogenetic signals. Our comparative study provides approaches and perspectives on the analysis of originality across biological scales of organization from individuals, through populations, up to the originalities of communities and regions.     

Floristic variation,chorological types and diversity: do they correspond at broad and local scales?

Abstract. The relationships between biogeographical patterns and local‐scale patterns based on microscale features, such as topoclimate, are well known in plant biogeography. Here we present a method of determining this correspondence using constrained ordination and correlations. We examined compositional gradients at two different scales, biogeographical chorotypes, and diversity. Compositional data (124 taxa × 113 plots) were sampled at four regularly spaced sites in south‐eastern Spain. Longitude (LONGI) was used as a spatial variable representing an east–west climate gradient, together with a radiation index (RADIN), elevation, and a disturbance indicator. All factors correlated with the compositional gradients, but the local‐topoclimate factor (RADIN) and the broad‐scale factor (LONGI) were most important. These two, spatially independent factors were both correlated with the two first ordination axes, and therefore should relate to the same general trend in species‐turnover. There was a significant Spearman's rank correlation between the species order along these two gradients. This is interpreted as an ecological self‐similar pattern, i.e. coenoclines repeating at different scales. A consistent order of species along local‐ and broad‐scale coenoclines may indicate that similar operational factors act at several scales, here related to moisture and temperature. The distribution of Mediterraneo–Macaronesian, Mediterraneo–Saharo–Arabian and Ibero–Maghribian species confirmed the correspondence between the broad‐ and local‐scale gradients. The former group decreases in number with increasing aridity along both gradients, whereas the two latter groups increase. A discordant pattern was found with south‐eastern Iberian endemics, but this may be explained by several of them being edaphic (saxicolous) specialists. There is a significant decrease in species richness with high radiation, but the expected increase along the longitudinal gradient from west (dry) to east (moist) was not statistically significant. This may be due to the correspondence between high richness and disturbance, both occurring in the middle of the broad‐scale gradient.     

Biotic diversification in the Guayana Highlands: a proposal

Until recently, the high degree of diversity and endemism of the Guayana Highlands was explained within the frame of the refuge theory. Although this hypothesis is unsupported by recent palaeoecological evidence, no new diversification model has been proposed. This paper is a proposal based on the latest palynological findings that indicate a downward biotic migration of c. 1100 m altitude during glacials, and the subsequent interglacial upward shift, in response to colder and warmer climates, respectively. Therefore, during glacials, biotic mixing is expected in the lowlands, thus promoting sympatric speciation, hybridization and polyploidy. At the mountaintops, unknown cold‐adapted taxa and páramo‐like(?) communities are expected to have occurred, and vicariance prevailed. In the interglacials, many taxa have had the opportunity for ascending to the mountains again, allowing genetic interchange among their slopes and summits, while others would have been adapted to lowlands. The interglacial highland communities, where vicariance still predominated, experienced some extinction owing to habitat loss by upland displacement. According to this model, the successive alternation of glacials and interglacials resulted in a net increase of diversity and endemism, favoured by the complex topography and habitat heterogeneity, which allowed high niche diversification. This model has some similarities with the Andean and Amazon modes of diversification, but the special topographical characteristics of the Guayana region made it different in other fundamental aspects. The Guayana Highlands would have acted as a ‘biodiversity pump’ for the surrounding inner and coastal lowlands, due to the repeated speciation and further spreading events, as a response to climate. Several working hypotheses are suggested in relation to the proposed model. The use of coordinated international multiproxy projects combining palaeoecology and genetic analysis of modern taxa is strongly encouraged for exploring these ideas.     

Vicariance and endemism in a Neotropical savanna hotspot: distribution patterns of Cerrado squamate reptiles

Aim To test predictions of the vicariance model, to define basic biogeographical units for Cerrado squamates, and to discuss previous biogeographical hypotheses. Location Cerrado; South American savannas south of the Amazon, extending across central Brazil, with marginal areas in Bolivia and Paraguay and isolated relictual enclaves in adjacent regions. Methods We compiled species occurrence records via field sampling and revision of museum specimens and taxonomic literature. All species were mapped according to georeferenced locality records, and classified as (1) endemic or non‐endemic, (2) typical of plateaus or depressions, and (3) typical of open or forested habitats. We tested predictions of the vicariance model using biotic element analysis, searching for non‐random clusters of species ranges. Spatial congruence of biotic elements was compared with putative areas of endemism revealed by sympatric restricted‐range species. Effects of topographical and vegetational mosaics on distribution patterns were studied according to species composition in biotic elements and areas of endemism. Results We recorded 267 Cerrado squamates, of which 103 (39%) are endemics, including 20 amphisbaenians (61% endemism), 32 lizards (42%) and 51 snakes (32%). Distribution patterns corroborated predictions of the vicariance model, revealing groups of species with significantly clustered ranges. An analysis of endemic species recovered seven biotic elements, corroborating results including non‐endemics. Sympatric restricted‐range taxa delimited 10 putative areas of endemism, largely coincident with core areas of biotic elements detected with endemic taxa. Distribution patterns were associated with major topographical and vegetational divisions of the Cerrado. Endemism prevailed in open, elevated plateaus, whereas faunal interchange, mostly associated with forest habitats, was more common in peripheral depressions. Main conclusions Our results indicate that vicariant speciation has strongly shaped Cerrado squamate diversity, in contrast to earlier studies emphasizing faunal interchange and low endemism in the Cerrado vertebrate fauna. Levels of squamate endemism are higher than in any other Cerrado vertebrate group. The high number of recovered endemics revealed previously undetected areas of evolutionary relevance, indicating that biogeographical patterns in the Cerrado were poorly represented in previous analyses. Although still largely undocumented, effects of vicariant speciation may be prevalent in a large fraction of Cerrado and Neotropical biodiversity.