Using crisp and fuzzy modelling to identify favourability hotspots useful to perform gap analysis

In this study, we propose the use of a favourability function to perform Gap Analysis. To exemplify this, we modelled the distribution of terrestrial mammal species in Andalusia (South of Spain) on the basis of their presence/absence on a grid of 10 km × 10 km UTM cells (n = 961). Using logistic regression and 30 variables related with the environment, space and human influence, we obtained probabilities of occurrence for each species in each cell. We computed a crisp favourability index considering the areas as favourable or unfavourable for a species if the probability of occurrence was higher or lower than the species prevalence, respectively. We also used a favourability function and fuzzy logic to level all species to the same threshold of favourability, which allowed to compare and to combine species distributions. Adding up the fuzzy favourability values for each species in each cell we obtained a fuzzy favourability index that we compared with species richness (sum of species in each cell) and with the crisp favourability index. We performed Gap Analysis by overlapping these results with the current reserve network of Andalusia. Gaps were grouped in fewer and bigger zones after applying the favourability indices. Considerations and recommendations for the use of the favourability function to select areas of conservation interest are discussed.     

Modelling the distribution of Bonelli's eagle in Spain: implications for conservation planning

Bonelli's eagle, Hieraaetus fasciatus, has recently suffered a severe population decline and is currently endangered. Spain supports about 70% of the European population. We used stepwise logistic regression on a set of environmental, spatial and human variables to model Bonelli's eagle distribution in the 5167 UTM 10 × 10 km quadrats of peninsular Spain. We obtained a model based on 16 variables, which allowed us to identify favourable and unfavourable areas for this species in Spain, as well as intermediate favourability areas. We assessed the stepwise progression of the model by comparing the model's predictions in each step with those of the final model, and selected a parsimonious explanatory model based on three variables — slope, July temperature and precipitation — comprising 76% of the predictive capacity of the final model. The reported presences in favourable and unfavourable areas suggest a source–sink dynamics in Bonelli's eagle populations. The fragmented spatial structure of the favourable areas suggests the existence of a superimposed metapopulation dynamics. Previous LIFE (The Financial Instrument of the European Union for the Environment and Nature) projects for the conservation of this species have focused mainly on the northern limit of its range, where the sharpest population decline has been recorded. In these areas, favourability is low and Bonelli's eagle populations are probably maintained by the immigration of juveniles produced in more favourable zones. However, southern populations, although stable, show signs of reduction in productivity, which could menace the population sizes in the whole study area. We suggest that conservation efforts should focus also on known favourable areas, which might favour population persistence in unfavourable areas through dispersal.     

Assessing the potential range expansion of the exotic monk parakeet in Spain

In this study we determine favourable areas for the monk parakeet, Myiopsitta monachus , in peninsular Spain to account for its current distribution and predict its future course according to its potential range. We applied a favourability function based on generalized linear models using the presence/absence of breeding colonies of the species and the values of a set of variables on the 5167 UTM 10 × 10 km squares comprising the study area. We calculated the factor of distribution change in presences predicted by the model, and grouped the variables into explanatory factors performing a variation partitioning to assess the explanatory power of each factor. Our model included six predictors to explain the presence and absence of the species. These predictors were grouped into three factors: human activity, climate, and topography. Purely human influences accounted for 63.8% of the variation of the final model, while topographical variables explained 15.2% and climate only 5.7%. We obtained a high distribution change factor in which the presences of the species were predicted to increase between two- and sevenfold. Taking into account highly favourable squares, we conclude that the species is still absent in more than 72% of potential settlement areas, and thus we expect a continuous increase in the distribution of the species. Human activity is the main force moulding the distribution of the species, and lies behind its fast expansion, which is not only active, but is also passive via releases and escapes. We identified the areas of likely future expansion of the exotic monk parakeet in Spain. The pest status of the species in its native range, together to its distribution trend, should be taken into account by wildlife agencies to consider options for management.     

On the concept of chorotype

Recent reviews of the meaning of the word ‘chorotype’ in biogeography have led to contrasting definitions and a confusion of concepts. This is because ‘chorotype’ has been used by different authors to express two different concepts: (1) groups of species with overlapping ranges (overall distributions) and (2) groups of species with a similar distribution within a certain area. To avoid confusion, I suggest the term ‘global chorotype’ be used to indicate a group into which species with similar ranges can be classified; and ‘regional chorotype’ be used for a group of species with similar distributions within a certain region. Although the global chorotype represents the world‐wide spatial responses of species to historical and environmental pressures, and does not vary with the area under consideration, a particular species might be classified into different regional chorotypes in different study areas.     

A model for range expansion of an introduced species: the common waxbill Estrilda astrild in Portugal

Abstract. The common waxbill Estrilda astrild was first introduced to Portugal from Africa in 1964, and has spread across much of the country and into Spain. We modelled the expansion of the common waxbill on a 20 × 20 km UTM grid in 4‐year periods from 1964 to 1999. The time variation of the square root of the occupied area shows that this expansion process is stabilizing in Portugal, and reasons for this are discussed. Several methods used to model biological expansions are not appropriate for the present case, because little quantitative data are available on the species ecology and because this expansion has been spatially heterogeneous. Instead, colonization on a grid was modelled as a function of several biophysical and spatio‐temporal variables through the fitting of a multivariate autologistic equation. This approach allows examination of the underlying factors affecting the colonization process. In the case of the common waxbill it was associated positively with its occurrence in adjacent cells, and affected negatively by altitude and higher levels of solar radiation.     

Distribution patterns of the small mammals (Insectivora and Rodentia) in a transitional zone between the Eurosiberian and the Mediterranean regions

To determine, by means of quantitative analyses, the distribution patterns of the insectivores and rodents in Catalonia using physiographical regions as Operative Geographical Units (OGUs). Catalonia (north‐eastern Iberian Peninsula). Based on the presence/absence of twenty‐five small mammals in thirteen physiographical regions, which were used as OGUs, the following aspects were studied: (a) identification of biotic boundaries; (b) determination of chorological association of species; (c) climatic characterization of the biotic regions and the chorotypes. Groups of biotic regions and species were established, and their statistical significance was tested. The possible effect of several climatic factors on these groupings was studied using discriminant analyses. A significant biotic boundary was found to separate the central and eastern Pyrenees from the remaining physiographical regions. The climatic variables that defined this boundary were related to the severity and the availability of environmental energy. Four chorotypes were identified. One chorotype was constituted by Pyrenean or Pre‐Pyrenean species, an association determined by their mid‐European requirements; another chorotype was formed by Eurosiberian species, but showed a variable degree of tolerance to Mediterranean conditions; a third chorotype included species with a wide distribution that are Mediterranean, anthropic, generalist or have very specific habitats; and finally the fourth chorotype was constituted by a strictly Mediterranean species. The climatic factors that accounted for the distribution of these chorotypes were the mean July temperature and the mean annual precipitation. We conclude that the axial zone of the Pyrenees, except the coastal portion, determines two biotic regions in Catalonia. As for the classification of species, using quantitative techniques for the first time, we offer a new biogeographicalal configuration for the small mammals in this temperate‐Mediterranean transition.     

The pace of past climate change vs. potential bird distributions and land use in the United States

Climate change may drastically alter patterns of species distributions and richness, but predicting future species patterns in occurrence is challenging. Significant shifts in distributions have already been observed, and understanding these recent changes can improve our understanding of potential future changes. We assessed how past climate change affected potential breeding distributions for landbird species in the conterminous United States. We quantified the bioclimatic velocity of potential breeding distributions, that is, the pace and direction of change for each species’ suitable climate space over the past 60 years. We found that potential breeding distributions for landbirds have shifted substantially with an average velocity of 1.27 km yr^?1, about double the pace of prior distribution shift estimates across terrestrial systems globally (0.61 km yr^?1). The direction of shifts was not uniform. The majority of species’ distributions shifted west, northwest, and north. Multidirectional shifts suggest that changes in climate conditions beyond mean temperature were influencing distributional changes. Indeed, precipitation variables that were proxies for extreme conditions were important variables across all models. There were winners and losers in terms of the area of distributions; many species experienced contractions along west and east distribution edges, and expansions along northern distribution edges. Changes were also reflected in the potential species richness, with some regions potentially gaining species (Midwest, East) and other areas potentially losing species (Southwest). However, the degree to which changes in potential breeding distributions are manifested in actual species richness depends on landcover. Areas that have become increasingly suitable for breeding birds due to changing climate are often those attractive to humans for agriculture and development. This suggests that many areas might have supported more breeding bird species had the landscape not been altered. Our study illustrates that climate change is not only a future threat, but something birds are already experiencing.     

Exploring species attributes and site characteristics to assess plant invasions in Spain

Aim Biological invasions are a major component of global change with increasing effects on natural ecosystems and human societies. Here, we aim to assess the relationship between plant invader species attributes and the extent of their distribution range size, at the same time that we assess the association between environmental factors and plant invader species richness. Location Spain, Mediterranean region. Methods From the species perspective, we calculated the distribution range size of the 106 vascular plant invaders listed in a recently published atlas of alien plant species in Spain. Range size was used as an estimation of the degree of invasion success of the species. To model variation in range size between species as a function of a set of species attributes, we adopted the framework of the generalized linear mixed models because they allow the incorporation of taxonomic categories as nested random factors to control for phylogenetic relationships. From the invaded site perspective, we determined invader plant species richness as the number of species for each 10 × 10 km Universal Transverse Mercator (UTM) grid. For each grid cell, we estimated variables concerning landscape, topography, climate and human settlement. Then, we performed a generalized linear mixed model incorporating a defined spatial correlation structure to assess the relationship between plant invader richness and the environmental predictors. Results From the species perspective, wind dispersal and minimum residence time appeared to favour invasion success. From the invaded site perspective, we identified high anthropogenic disturbance, low altitude, short distance to the coastline and dry, hot weather as the main correlates to UTM grid cell invader richness. Main conclusions According to these results, an increasing importance of man‐modified ecosystems and global warming in the Mediterranean region should facilitate the expansion of plant invaders, especially wind‐dispersed species, leading to the accumulation of invasive species in some sites (i.e. invasion hot spots).     

Species richness, area and climate correlates

Aim Species richness–area theory predicts that more species should be found if one samples a larger area. To avoid biases from comparing species richness in areas of very different sizes, area is often controlled by counting the numbers of co‐occupying species in near‐equal area grid cells. The assumption is that variation in grid cell size accrued from working in a three‐dimensional world is negligible. Here we provide a first test of this idea. We measure the surface area of c. 50 × 50 km and c. 220 × 220 km grid cells across western Europe. We then ask how variation in the area of grid cells affects: (1) the selection of climate variables entering a species richness model; and (2) the accuracy of models in predicting species richness in unsampled grid cells. Location Western Europe. Methods Models are developed for European plant, breeding bird, mammal and herptile species richness using seven climate variables. Generalized additive models are used to relate species richness, climate and area. Results We found that variation in the grid cell area was large (50 × 50 km: 8–3311 km²; 220 × 220: 193–55,100 km²), but this did not affect the selection of variables in the models. Similarly, the predictive accuracy was affected only marginally by exclusion of area within models developed at the c. 50 × 50 km grid cells, although predictive accuracy suffered greater reductions when area was not included as a covariate in models developed for c. 220 × 220 km grid cells. Main conclusions Our results support the assumption that variation in near‐equal area cells may be of second‐order importance for models explaining or predicting species richness in relation to climate, although there is a possibility that drops in accuracy might increase with grid cell size. The results are, however, contingent on this particular data set, grain and extent of the analyses, and more empirical work is required.     

Biogeographical zonation of African hornbills and their biotic and geographic characterisations

We studied the geographic ranges of the 23 African hornbill species using countries as distribution units, to search for either groups of similar distributions (chorotypes) or gradual replacement of species as two different types of distribution patterns. We used a probabilistic classification method to distinguish between these two types of biogeographic patterns. Then we analysed the influence of climate, area, surface covered by different types of habitat, and human disturbance in each country, as well as biotic features of the species involving the habitat preference, feeding requirements and habits, body size, sexual dimorphism, and metabolic parameters, on the biogeographic patterns detected. We found that 20 species were significantly classified into three chorotypes. The western-central chorotype comprises nine species characterised by their preference for forest habitat and their low sexual body mass dimorphism. These species occur in 25 countries, characterised by their low range of temperatures. The eastern chorotype includes three species characterised by their preference for feeding on the ground and greater dimorphism in mass between the sexes. Seven countries, characterised by their high values of savanna and grassland surface area, constitute the geographic element of this chorotype. The southern chorotype involves the distribution of eight species characterised by their preference for montane and coastal forests or woodlands. Eighteen countries fall into this chorotype and are characterised by their low values of temperature in the coldest month and greater surface area of desert scrub and desert forest. The other three species replace each other mainly following a gradual pattern within the study area.     

Variation partitioning for range expansion of an introduced species: the common waxbill Estrilda astrild in Portugal

The common waxbill Estrilda astrild was first introduced to Portugal, from Africa, in 1964, from where it has spread to much of the country and to Spain. We modelled the expansion of this species on a 20×20-km UTM grid in 4-year periods from 1964 to 1999. Colonisation process on a grid was modelled as a function of several biophysical and spatio-temporal variables through the fitting of several multiple logistic equations. Variation partitioning confirmed the importance of the spatial-temporal component, explaining 33% of the total variation, followed by the combined effects of both environmental and spatial-temporal variables (around 25%). Only 11% of the total variation can be attributed strictly to the considered environmental factors.     

Chorotypes of seaweeds from the western Mediterranean Sea and the Adriatic Sea: An analysis based on the genera Audouinella (Rhodophyta), Cystoseira (Phaeophyceae) and Cladophora (Chlorophyta)

The aim of the present paper is to identify the possible existence of groups of species in the genera Audouinella (Rhodophyta), Cystoseira (Phaeophyceae) and Cladophora (Chloropyta) with significantly similar distribution patterns (chorotypes), in the western Mediterranean Sea and the Adriatic Sea. Of the 98 species studied, 59 were grouped into 11 chorotypes, whereas 39 species remained ungrouped. Thirty‐eight species were included in a generalist chorotype, whereas 6 chorotypes were monospecific. The relationships with the environmental factors that could explain the chorotypes are discussed.     

Using chorotypes to deconstruct biogeographical and biodiversity patterns: the case of breeding waterbirds in Europe

Aim To deconstruct the biodiversity pattern of the 152 waterbird species breeding in Europe to better understand its multiple causal processes. Location Continental Europe, Iceland and the British Isles. Methods We considered the orders that are typically comprised by swimming, diving or wading birds, which inhabit marshes, fens, peatlands and fresh, brackish or salt waters, including coastal waters. We used the 55 main river basins of Europe as geographical units, and searched for either chorotypes (groups of similar species distributions) or gradual replacement of species throughout the river basins. Chorotypes were recognized by applying a probabilistic classification method to the distributions. Then we used GLM to characterize the extent and the species richness of each chorotype according to energy availability (higher levels of environmental energy favouring the presence of species), climatic stress due to an excess of energy, availability of water, productivity, seasonality and surface area. Results One hundred and forty species significantly aggregate into nine chorotypes. The other 12 species, most of them marine, are centred on Great Britain, dropping away progressively on coasts further away from there. Differences in either the availability of energy or climatic stress significantly characterized the distribution of seven chorotypes comprising 90.8% of the species. Main conclusions Chorotypes are meaningful and useful to deconstruct biodiversity patterns. Our results suggest that energy is the main factor related to the biogeographical patterns of breeding waterbirds in Europe, and provide an insight into regional trends of species richness previously analysed with a habitat‐scale perspective.     

The distribution patterns of reptiles in the Riff region, northern Morocco

A biogeographical classification of reptiles in the Riff region (northern Morocco, Africa) was carried out to look for shared distribution patterns, here termed chorotypes. Baroni‐Urbani & Buser's similarity index was applied to the presence/absence data of reptiles in 10×10 km UTM (Universal Transverse Mercator) squares, and then UPGMA (Unweighted Pair‐Group Method using arithmetic average) was used to classify the species. A probabilistic method was employed to assess the statistical significance of the groups obtained. An ordination method, the Canonical Correspondence Analysis, was also used to study the distribution of the reptiles within a continuous framework.
A gradual longitudinal replacement of reptile species was found throughout the Riff, with no sharp discontinuities for the distributions of most of the species. This may be due to the biogeographical northward movement of the Saharan boundaries, which have not yet reached biogeographical equilibrium. Thus, Saharan reptiles enter the Riff region from the east, through the lower basin of the River Moulouya.
Seven reptile chorotypes were identified in the Riff, and these comprise Mediterranean species and others endemic to the Maghreb (the region that spans most of North‐western Africa, excluding the Sahara). These chorotypes have a western distribution, and are segregated from one another according to altitude. Historical and ecological processes can account for the distributions shared by these species, which have inhabited the Riff for longer than eastern reptiles.     

Land use and environmental factors affecting red-legged partridge (Alectoris rufa) hunting yields in southern Spain

The red-legged partridge is a small game species widely hunted in southern Spain. Its commercial use has important socioeconomic effects in rural areas where other agrarian uses are of marginal importance. The aims of the present work were to identify areas in Andalusia (southern Spain) where game yields for the red-legged partridge reach high values and to establish the environmental and land use factors that determine them. We analysed 32,134 annual hunting reports (HRs) produced by 6,049 game estates during the hunting seasons 1993/1994 to 2001/2002 to estimate the average hunting yields of red-legged partridge in each Andalusian municipality (n=771). We modelled the favourability for obtaining good hunting yields using stepwise logistic regression on a set of climatic, topographical, land use and vegetation variables that were available as digital coverages or tabular data applied to municipalities. Good hunting yields occur mainly in plain areas located in the Guadalquivir valley, at the bottom of Betic Range and in the Betic depressions. Favourable areas are related to highly mechanised, low-elevation areas mainly dedicated to intensive dry crops. The most favourable areas predicted by our model are mainly located in the Guadalquivir valley.     

Distribution and movement of juvenile and sub‐adult Chinese sturgeon (Acipenser sinensis Gray, 1835) in the Three Gorges Reservoir and the adjacent upstream free‐flowing Yangtze River section: a re‐introduction trial

The aim of this 2008–2012 study was to prove the hypothesis that the Three Gorges Reservoir (TGR) and the upper free‐flowing section can offer a habitat for restocking the Chinese sturgeon, Acipenser sinensis. Thus, 498 cultured A. sinensis (including 28 sub‐adults tagged with ultrasonic transmitters) were released into the TGR and the adjacent free‐flowing section of the Yangtze River. The distribution, movement and growth of the released fish were collected by acoustic telemetry and bycatch information. Results indicated that only three sub‐adults migrated upstream to the free‐flowing section where they remained for the three‐year observation (limited by the longevity of the transmitter battery). However, most sub‐adults migrated downstream after release, with a migration distance of 15–877 km as well as a tracking duration from 19 to 6063 h. The downstream traveling speed in the free‐flowing section (mean = 3.70 km h^?1, range = 1.51 – 8.25 km h^?1) was significantly faster than that in the reservoir section (mean = 1.05 km h^?1, range = 0.12 – 1.82 km h^?1; p < 0.05). Only three sub‐adults migrated to within 3 km of Three Gorges Dam (TGD) and stayed in the reservoir. Sub‐adults stayed obviously deeper within the reservoir (mean = 11.47 m) than in the free‐flowing section (mean = 3.63 m; p < 0.05). Juveniles were recaptured from 45 – 810 km downstream their release sites with a mean traveling speed of 1.05 km h^?1 (range = 0.13 – 1.82 km h^?1), lower than that of the sub‐adults released in the free‐flowing section. Twelve percent of juveniles released in one of the tributaries of the Yangtze River found the entrance and migrated downstream to the reservoir within the first 30 days. Average body weight of the recaptured juveniles increased by 10.3% (range = 2.3% – 15.3%) and some crustaceans (e.g. river shrimp) were found in the stomach and gut of two juveniles. The results demonstrate that the TGR and its adjacent upstream free‐flowing Yangtze River section can serve as reintroduction sites to support a certain quantity of Chinese sturgeon to remain and mature there.     

Area Networks for Conserving Iberian Insects: A Case Study of Dung Beetles (col., Scarabaeoidea)

Possibilities to create an efficient network of areas for the conservation of Iberian dung-beetle biodiversity were investigated. Data were taken from BANDASCA, a 15,740 record dung-beetle database with information for 101,996 specimens. The greatest species richness and phylogenetic diversity are found in the Iberian Central System cordilleras, while those of range-size rarity are in the southernmost corner of the Iberian Peninsula and in the coastal plains of the Guadalquivir basin. Additionally, broad regional score trends of these variables reach a maximum in a smaller northeastern, and a larger southeastern region (Baetic and sub-Baetic mountains). Major Central and Southern Spain dung-beetle hotspots contain many of the UTM grid cells which delimit the near-minimum-set of areas hosting maximum dung-beetle biodiversity scores. They are viewed as the nucleus of a potential network of reserves. A UTM grid cell (30TXK1) where Onthophagus albarracinus, an endemic and demographically rare species inhabits the Sierra of Albarracín and Montes Universales, was detected as an irreplaceable area. Because of recent land use changes and rapid human-induced habitat transformation threatening dung-beetle fauna, caution should be taken not to recommend an in memoriam network of areas no longer hosting a fauna extinct today. The abandoning of traditional herding management in Europe threatens the preservation of grasslands where dung-feeding beetles play a major ecological role in maintaining pasture quality and livestock health. A return to more traditional herding methods would require stable dung-beetle populations. Any insect conservation planning in Spain would benefit from more biogeographical information for other insect groups.     

基于Dobson算法的中国受威胁陆栖哺乳类优先保护识别与保护现状分析

优先保护区识别对受威胁物种的多样性保护具有重要价值。基于GIS空间分析、管理及预测能力,以中国受威胁陆栖哺乳动物为对象,建立受威胁物种的分布二值网格系统;利用Dobson算法对研究区3810个网格单元进行筛除,确定全国范围下受威胁物种的优先保护区域;结合中国主要的自然保护地分布数据（国家公园和自然保护区）,采用保护空缺方法分析优先保护区内受威胁动物的保护现状。研究发现,29个50km×50km的网格单元就包含了全部的受威胁陆栖哺乳物种,其中位于喜马拉雅山东南区等地的10个网格区域覆盖有80%以上的物种,其所处的10组县级行政区内被主要自然保护地保护的土地面积占25.9%,物种数占83.6%,存在一定的保护空缺。本文采用Dobson排除算法,以小面积规则网格为基本单元,顾及到了实验结果的客观性,有助于提高优先保护区的识别效率。     

Explanations for bird species range size: ecological correlates and phylogenetic effects in the Canary Islands

Aim To explore the determinants of island occupancy of 48 terrestrial bird species in an oceanic archipelago, accounting for ecological components while controlling for phylogenetic effects. Location The seven main islands of the Canary archipelago. Methods We obtained field data on population density, habitat breadth and landscape distribution in Tenerife, Fuerteventura and La Palma, aiming to sample all available habitats and the gradient of altitudes. In total, 1715 line transects of 0.5 km were carried out during the breeding season. We also reviewed the literature for data on occupancy, the distance between the Canary Islands and the nearest distribution border on the mainland, body size and endemicity of the 48 terrestrial bird species studied. Phylogenetic eigenvector regression was used to quantify (and to control for) the amount of phylogenetic signal. Results The two measurements of occupancy (number of occupied islands or 10 × 10 km UTM squares) were tightly correlated and produced very similar results. The occupancy of the terrestrial birds of the Canary Islands during the breeding season had a very low phylogenetic effect. Species with broader habitat breadth, stronger preferences for urban environments, smaller body size, and a lower degree of endemicity had a broader geographical distribution in the archipelago, occupying a larger number of islands and 10 × 10 UTM squares. Main conclusions The habitat‐generalist species with a tolerance for novel urban environments tend to be present on more islands and to occupy a greater area, whereas large‐sized species that are genetically differentiated within the islands are less widespread. Therefore, some properties of the ranges of these species are explicable from basic biological features. A positive relationship of range size with local abundance, previously shown in continental studies, was not found, probably because it relies on free dispersal on continuous landmasses, which may not be applicable on oceanic islands.     

Quantitative phytogeography of the Italian Beech Forests

This paper presents a numerical analysis of the distribution patterns in Europe and adjoining regions of 242 vascular plant species occurring in the Italian beech forests. The classification of a matrix of species and of 531 Operational Geographic Units (OGUs) led to recognition of 15 different phytogeographic elements (chorotypes). The joint distribution of the species belonging to each chorotype is shown by a chorogram, which is a geographic map obtained by computer processing of the distributional data. Some of the chorograms show the main distributional centers for the beechwood flora in southern Europe: northwestern Balkan Peninsula and eastern Alps, southern Balkan Peninsula, Maritime Alps, northern Apennines, southern Apennines. Only 20% of the species are limited to narrow areas in southern Europe, and were not able to expand considerably their ranges in postglacial times. Migration from the refugia and colonization of vast areas in central and northern Europe led to intensive speciation phenomena, occurring chiefly through the formation of neopolyploid species. Several south European, narrow-ranging species, can be considered as palaeopolyploids with relict character. There is a good relationship between distribution and ecology of the chorotypes.Abbreviations OGU Operational Geographic Unit - OGS Operational Geographic Set - OCS Operational Character Set