Abstract. Water resources and associated ecosystems are becoming highly endangered due to ongoing global environmental changes. Spatial ecological modelling is a promising toolbox for understanding the past, present and future distribution and diversity patterns in groundwater-dependent ecosystems, such as fens, springs, streams, reed beds or wet grasslands. Still, the lack of detailed water chemistry maps prevents the use of reasonable models to be applied on continental and global scales. Being major determinants of biological composition and diversity of groundwater-dependent ecosystems, groundwater pH and calcium are of utmost importance. Here we developed an up-to-date European map of groundwater pH and Ca, based on 7577 measurements of near-surface groundwater pH and calcium distributed across Europe. In comparison to the existing European groundwater maps, we included several times more sites, especially in the regions rich in spring and fen habitats, and filled the apparent gaps in eastern and southeastern Europe. We used random forest models and regression kriging to create continuous maps of water pH and calcium at the continental scale, which is freely available also as a raster map (Hájek et al., 2020b; https://doi.org/10.5281/zenodo.4139912). Lithology had a higher importance than climate for both pH and calcium. The previously recognised latitudinal and altitudinal gradients were rediscovered with much refined regional patterns, as associated with bedrock variation. For ecological models of distribution and diversity of many terrestrial ecosystems, our new map based on field groundwater measurements is more suitable than maps of soil pH, which mirror not only bedrock chemistry but also vegetation-dependent soil processes.

Question Fens have a well‐developed bryophyte layer covering most of the ground. Non‐sphagnaceous bryophytes, especially the group of so‐called brown mosses, prevail over sphagna under alkaline conditions. In sub‐alkaline conditions, rich fens allow the co‐occurrence of both these functional groups, but sphagna are competitively superior over non‐sphagnaceous bryophytes and seedlings of vascular plants, and they are currently expanding in some regions. We test whether the ratio between the two major bryophyte functional groups (bryo‐ratio) accounts for the species composition of vascular plants in fens. Location Central and Eastern Europe. Methods Analysis of two existing regional‐ and continental‐scale data sets of the vegetation‐ plot records and measured local factors by Canonical Correspondence Analysis with variation partitioning (community‐level analysis) and Structural Equation Modelling (species‐level analysis). Results At the community level, the bryo‐ratio accounted significantly for species composition of fen‐specialized vascular plants, more obviously in the regional‐scale data set. At the species level, more fen species (50–67% according to the data set) were significantly directly affected (adjusted p < 0.05) by the bryo‐ratio than by water pH (14–17%) and by measured water table depth (WTD) in the regional data set (12.5%). In the continental data set, the comparable proportions of species were directly affected by the bryo‐ratio and WTD inferred by soil moisture indicator values (50% vs 58%). Most of the species affected significantly by the bryo‐ratio preferred the fens rich in non‐sphagnaceous bryophytes. They were largely those with a low capability of vegetative reproduction. Conclusions The group of species preferring brown moss patches includes mostly rare and endangered species with a great need for generative reproduction (e.g., Primula farinosa, Triglochin palustris, Pedicularis palustris, Saxifraga hirculus). Our findings demonstrate the important role of the bryophyte layer in the structuring of vascular plant communities in fens and highlight urgent conservation needs for brown moss patches.

M. (2018): Using a new database of plant macrofossils of the Czech and Slovak Republics to compare past and present distribution of hypothetically relict fen mosses. -Preslia 90: 367-386.Modern databases containing large amounts of botanical data are a promising source of new results based on large data analyses. We used a new database of plant macrofossils of the Czech and Slovak Republics to compare the recent distributions of putative relict species of fen bryophytes with their past distributions since the late glacial. All the species studied occur in lateglacial sediments, but mostly in regions where they are recently recorded (19-21st centuries). There are specific regions rich in putative relict species of fen bryophytes both in late glacial / early Holocene times and recently. In some cases the target species were, however, found outside the recent distribution range where environmental conditions are no longer suitable for their occurrence. We further found that the total number of the glacial and early-Holocene records greatly exceeds the total number of records for the middle Holocene, when succession to woodlands or bogs resulted in a reduction in species of bryophytes that are specific to open rich fens. The observed patterns may imply a relict status of the target species. We especially documented a substantial decline in the abundance of species requiring a high and stable water level (Drepanocladus trifarius, Meesia triquetra and Scorpidium scorpioides), both throughout the Holocene and during the most recent transformations of the landscape. In contrast, those species that tolerate transient decreases in water level persisted into recent times at more localities (Calliergon giganteum, Hamatocaulis vernicosus, Paludella squarrosa). Macrofossil data cannot, however, provide a quantitative analysis of the distribution of a species, because the number of recent data usually greatly exceeds the number of fossil records. The reason is that the area sampled in palaeoecological research is very small as it is time-consuming and expensive; cores or excavations usually are of only a few square centimetres. Despite this shortcoming, macrofossil data are an important, but not the only, source of evidence for the identification of the relict status of a species.

QuestionFiltering vegetation plot records according to sampling size is an essential methodological step in vegetation studies. In fens, the variation of traditionally used plot sizes seems to limit continental‐scale syntheses following the Braun‐Blanquet approach. Which plot sizes harbour the analogous number of habitat specialists (i.e., diagnostic/indicator species) and capture the main compositional gradients identically?LocationScandinavia, central Europe.MethodsThe data set of fen vegetation plot records was compiled using large databases and categorised into four distinct habitats. For each habitat, semi‐log species–area curves of specialists and other species were fitted using generalised additive models (GAM). In addition, we surveyed 72 sites in a series of plot sizes (0.07, 0.25, 1, 4, 16 m2) where we applied, separately for each plot size, Non‐Metric Multi‐Dimensional Scaling (NMDS) and compared the resulting patterns with Procrustes analysis.ResultsConsistently across different fen habitats, the species–area curves of specialists increased steeply up to the plot size of 1 m2, while increasing negligibly in the plot size range of 1–25 m2. In contrast, the species–area curves of other species displayed mostly linear to linear‐exponential trends. NMDS ordinations of medium (1 and 4 m2) and large plots (16 m2) were the most congruent, while the patterns captured in the ordination of the smallest plots (0.07 m2) differed most from the others.ConclusionsIn fens, plot sizes of at least 1 m2 describe sufficiently the broad‐scale pattern in specialists’ diversity as well as the main environmental gradients. The range of plot sizes of 1–25 m2 may be safely merged in broad‐scale analyses of fen vegetation without introducing substantial bias, at least when compared with other possible uncertainty sources.

Polyethylene glycol (PEG) was used to produce whole-virus antigen derived from tissue culture cells infected with a Canadian strain of caprine arthritis-encephalitis virus. PEG antigen batches were obtained after precipitation and concentration of infected tissue culture material with PEG 8000 and final treatment with sodium dodecyl sulfate. The optimum time of harvest of tissue culture extracted material to produce the maximum amount of viral proteins was determined in roller bottles, after cocultivation of infected and noninfected fetal lamb corneal cells. Samples from day 9 to day 25 postculture were collected and processed. By Western blotting, the optimum time of harvest was found to be day 25 following the coculture. Two large batches of PEG antigen were prepared at the optimum time of harvest. Both batches gave similar results when tested by Western blotting and enzyme-linked immunosorbent assay (ELISA), using reference control sera from infected and noninfected goats. For further testing in ELISA, cutoff values and ratios were determined for PEG batch 1, using 200 known serum samples from goats free of the disease. The PEG antigen batch was compared with an in-house ELISA antigen in a kinetic mode, using 498 serum samples from field goats. The in-house ELISA antigen was produced following two rounds of ultracentrifugation and treatment with sodium dodecyl sulfate (R. A. Heckert, W. B. McNab, S. M. Richardson, and M. R. Briscoe, Can. J. Vet. Res. 56:237-241, 1992). The PEG antigen batch was found suitable for ELISA, with a relative specificity of 100% and a relative sensitivity of 99.4% compared to the in-house ELISA antigen. This method of antigen production for ELISA was found to be rapid, inexpensive, and reliable for the diagnosis of caprine-arthritis encephalitis, without requiring the use of sophisticated laboratory equipment.Caprine arthritis-encephalitis virus (CAEV) belongs to the Retroviridae family and the subfamily Lentivirinae. The virus is distributed worldwide and causes leuko-encephalomyelitis in goat kids (13), chronic progressive arthritis-synovitis, indurative mastitis, and chronic interstitial pneumonia in adult goats (6,9,12). The development of clinical disease takes a few months to a few years, with infections in most animals remaining subclinical (7,15). For both the clinical and asymptomatic forms, the CAEV causes a lifetime infection despite humoral and cellular immune responses (8), with no known effective treatment; the infected animals remain reservoirs of the virus for their entire lives. Transmission between infected and susceptible animals occurs mainly through colostrum and milk consumption (1,15). Contact transmission between goats of all ages has also been demonstrated (15). The early detection of the infected animals and their segregation and/or eradication from the flock form an efficient practice to limit the spread of the virus (17). The infection is primarily detected by the demonstration of specific CAEV antibodies in the body fluids of the infected goats (15). The...