Glacial Refugia and Future Habitat Coverage of Selected Dactylorhiza Representatives (Orchidaceae)

New and Noteworthy Taxa of the Genus Dactylorhiza Necker ex Nevski (Orchidaceae Juss.) in Kazakhstan Flora and Its Response to Global Warming

A critical study of the herbarium material representing the orchid genus Dactylorhiza Necker ex Nevski in Kazakhstan was conducted in 2019–2020. The information on the species composition was clarified. Dactylorhiza fuchsii subsp. hebridensis (Wilmott) Soó and D. × kerneri (Soó) Soó were identified for the first time in the country. New taxa were noted for individual botanical and geographical areas. All taxa were presented in the list and annotated with studied herbarium materials from the Kazakhstan area. Based on the collected and available locations for the studied taxa, distribution modeling was carried out for the four taxa (D. incarnata, D. majalis subsp. baltica, D. salina, and D. umbrosa). Bioclimatic data for the present and future (2041–2060) based on four possible scenarios were used. The occurrence of Dactylorhiza representatives in Kazakhstan is threatened by global climate warming. It is likely that some of them may not occur in the country in the future (D. incarnata and D. majalis subsp. baltica), losing up to 99.87% of their modern range or their range may be significantly reduced (D. salina and D. umbrosa), losing up to 80.83% of their present distribution. It is worth considering global changes in planning conservation activities and identifying areas that may play a significant role in the functioning of the national flora in the future.

Ecological niche modeling of the pantropical orchid Polystachya concreta (Orchidaceae) and its response to climate change

Climate is the dominant control factor on the spatial distribution of organisms on a global scale and global warming is predicted to become a major cause of species extinctions. In our study ecological niche modeling (ENM) was used to estimate the effect of projected future climate changes on the pantropical orchid Polystacha concreta as well as to reconstruct changes in the distribution of the suitable climatic niches of this species since the Last Glacial Maximum (LGM). The study revealed small differences in the niches occupied by populations of P. concreta recorded in various continents; however, these alterations will become more significant in regard to future climatic change. While losses of suitable habitats of the studied orchid will occur in the Americas and Africa, global warming will be favorable for Asian populations. Our study suggests a significant loss of niches since the LGM which indicates that the currently observed loss of habitats is not only the result of human activity but also of natural changes of the Earth’s climate. From the obtained models we identified the areas that will be the most resistant regarding the modifications caused by climate change.

A Synopsis of Sardinian Studies: Why Is it Important to Work on Island Orchids?

Biological and ecological investigations of islands are crucial to explain ecosystem functioning. Many studies on island biodiversity are carried out on oceanic islands. In contrast, information on continental islands, such as those in the Mediterranean Sea, is very often fragmented in space and time. Here, a synopsis of the Orchidaceae of Sardinia is presented based on literature surveys and recent botanical field studies. Our final list comprises of 64 species and 14 genera: thirteen species and subspecies were recognized as endemic and four new species were recorded for the flora of the island: Anacamptis palustris (Jacq.) R.M. Bateman, Pridgeon & M.W. Chase; Himantoglossum hircinum (L.) Spreng; Orchis italica Poir.; and Platanthera kuenkelei subsp. kuenkelei var. sardoa R.Lorenz, Akhalk., H.Baumann, Cortis, Cogoni & Scrugli. This orchid richness reflects the geological history of the island that was linked to the mainland several times, facing long periods of isolation. We also discuss a critical point-of-view of the biodiversity shortfalls still problematic for insular orchids. Indeed, within the Mediterranean Basin, the greatest amount of endemism occurs mainly on large islands, and, despite a long history of botanical exploration in European countries, many of them are scarcely investigated. This annotated synopsis shows the potential of continental islands to understand trends in ecology and evolution. Further studies are required to complete our knowledge of the orchid diversity on continental islands in order to propose scientific-based conservation programs to preserve these unique taxa.

Species Richness, Ecology, and Prediction of Orchids in Central Europe: Local-Scale Study

Orchids are one of the most species-rich families in the world, and many species are under threat in numerous countries. Biodiversity research focusing on the relationship between the richness of orchid species and ecological factors was performed across the Cerová vrchovina Mts (Western Carpathians) testing impact of 26 explanatory variables. We aimed to determine the main ecological predictors controlling species richness and to predict potential species richness patterns. Altogether, 19 orchid species were found in the studied area, with Cephalanthera damasonium and Epipactis microphylla being the most common. Four environmental predictors (minimal longitude, carbonate-containing sediments, maximal yearly solar irradiation, and agricultural land) had statistically significant effects on orchid richness following regression analysis. Predictive models for the nine most frequent species using MaxEnt software showed (i) that land cover and geological substrate had the highest contribution to the explained variance in the models and (ii) strong potential for occurrence of given orchids in several poorly mapped parts of the studied area.

Is the lady's-slipper orchid (Cypripedium calceolus) likely to shortly become extinct in Europe?-Insights based on ecological niche modelling

Lady's-slipper orchid (Cypripedium calceolus) is considered an endangered species in most countries within its geographical range. The main reason for the decline in the number of populations of this species in Europe is habitat destruction. In this paper the ecological niche modelling approach was used to estimate the effect of future climate change on the area of niches suitable for C. calceolus. Predictions of the extent of the potential range of this species in 2070 were made using climate projections obtained from the Community Climate System Model for four representative concentration pathways: rcp2.6, rcp4.5, rcp6.0 and rcp8.5. According to these analyses all the scenarios of future climate change will result in the total area of niches suitable for C. calceolus decreasing. Considering areas characterized by a suitability of at least 0.4 the loss of habitat will vary between ca. 30% and 63%. The highest habitat loss of ca. 63% is predicted to occur in scenario rcp 8.5. Surprisingly, in the most damaging rcp 8.5 prediction the highest overlap between potential range of C. calceolus and its pollinators will be observed and in all other scenarios some pollinators will be available for this species in various geographical regions. Based on these results at least two approaches should be implemented to improve the chances of survival of C. calceolus. In view of the unavoidable loss of suitable habitats in numerous European regions, conservation activities should be intensified in areas where this species will still have suitable niches in the next 50 years. In addition, for C. calceolus ex-situ activities should be greatly increased so that it can be re-introduced in the remaining suitable areas.

Biogeography and genotypic diversity of Metarhizium brunneum and Metarhizium robertsii in northwestern North American soils

The biogeography and genotype diversity of Metarhizium species in northwestern North American soils was examined; 20 ecoregions were sampled, including 58 agricultural and 80 natural habitat subsites, and areas that were glaciated during the Pleistocene epoch. One hundred and twenty-nine isolates of M. brunneum, 26 isolates of M. robertsii, four isolates of M. guizhouense, one isolate of M. flavoviride, and 55 isolates of Beauveria were recovered. Metarhizium and Beauveria species were isolated in diverse ecoregions within the study area, but a trend for increased isolation of Metarhizium species in western regions of the study area was observed. Consistent with this observation, the prevalence of M. brunneum and M. robertsii decreased at higher elevations, and the opposite was true for Beauveria. Both M. brunneum and M. robertsii were more commonly isolated from agricultural and natural habitat subsites, and considerable genotypic diversity was observed in both habitats and within the same subsite. Metarhizium robertsii, but not M. brunneum, was more commonly isolated from nonglaciated locations; however, less diversity and richness was observed for M. brunneum recovered from glaciated versus nonglaciated locations consistent with insular biogeography. The study has implications for microbial control strategies in the region.

Global warming not so harmful for all plants - response of holomycotrophic orchid species for the future climate change

Current and expected changes in global climate are major threat for biological diversity affecting individuals, communities and ecosystems. However, there is no general trend in the plants response to the climate change. The aim of present study was to evaluate impact of the future climate changes on the distribution of holomycotrophic orchid species using ecological niche modeling approach. Three different scenarios of future climate changes were tested to obtain the most comprehensive insight in the possible habitat loss of 16 holomycotrophic orchids. The extinction of Cephalanthera austiniae was predicted in all analyses. The coverage of suitable niches of Pogoniopsis schenckii will decrease to 1-30% of its current extent. The reduction of at least 50% of climatic niche of Erythrorchis cassythoides and Limodorum abortivum will be observed. In turn, the coverage of suitable niches of Hexalectris spicata, Uleiorchis ulaei and Wullschlaegelia calcarata may be even 16-74 times larger than in the present time. The conducted niche modeling and analysis of the similarity of their climatic tolerance showed instead that the future modification of the coverage of their suitable niches will not be unified and the future climate changes may be not so harmful for holomycotrophic orchids as expected.

Evolution of the climatic tolerance and postglacial range changes of the most primitive orchids (Apostasioideae) within Sundaland, Wallacea and Sahul

The location of possible glacial refugia of six Apostasioideae representatives is estimated based on ecological niche modeling analysis. The distribution of their suitable niches during the last glacial maximum (LGM) is compared with their current potential and documented geographical ranges. The climatic factors limiting the studied species occurrences are evaluated and the niche overlap between the studied orchids is assessed and discussed. The predicted niche occupancy profiles and reconstruction of ancestral climatic tolerances suggest high level of phylogenetic niche conservatism within Apostasioideae.