Climatically promoted taxonomic homogenization of macroinvertebrates in unaffected streams varies along the river continuum.

Biotic homogenization appears to be a global consequence of anthropogenic change. However, the underlying environmental factors contributing to homogenization are difficult to identify because their effects usually interact and confound each other. This can be the reason why there is very little evidence on the role of climate warming in homogenization. By analysing macroinvertebrate assemblages in 65 streams that were as close to natural conditions as possible, we avoided the confounding effects of common anthropogenic stressors. This approach resulted in revealing a significant effect of increased temperature (both summer and winter) on changes in macroinvertebrate compositional over the past two decades. However, homogenization was significant only at opposite ends of the river continuum (submontane brooks, low-altitude rivers). Surprisingly, species of native origin predominated overall, increasing in frequency and abundance ("winners"), while only a minority of species declined or disappeared ("losers"). We hypothesise that undisturbed conditions mitigate species declines and thus homogenization, and that the temperature increase has so far been beneficial to most native species. Although we may have only captured a transitional state due to extinction debt, this underscores the importance of maintaining ecological conditions in stream to prevent species loss due to climate change.

Actinotignum schaalii: Relation to Concomitants and Connection to Patients' Conditions in Polymicrobial Biofilms of Urinary Tract Catheters and Urines.

Actinotignum schaalii is an emerging, opportunistic pathogen and its connection to non-infectious diseases and conditions, such as prostate or bladder cancer, or chronic inflammation has been proposed. Here, we analyzed 297 urine, ureteral and urinary catheter samples from 128 patients by Polymerase Chain Reaction followed by Denaturing Gradient Gel Electrophoresis and Sequencing (PCR-DGGE-S), and culture, and 29 of these samples also by 16S rRNA Illumina sequencing, to establish A. schaalii's prevalence in urinary tract-related samples, its relation to other bacteria, and its potential association with patients' conditions and samples' characteristics. A. schaalii-positive samples were significantly more diverse than A. schaalii negative and between-group diversity was higher than intra-group. Propionimicrobium lymphophilum, Fusobacterium nucleatum, Veillonella sp., Morganella sp., and Aerococcus sp. were significantly more often present in A. schaalii-positive samples; thus, we suggest these species are A. schaalii's concomitants, while Enterobacter and Staphylococcaceae were more often identified in A. schaalii-negative samples; therefore, we propose A. schaalii and these species are mutually exclusive. Additionally, a significantly higher A. schaalii prevalence in patients with ureter stricture associated hydronephrosis (p = 0.020) was noted. We suggest that A. schaalii could be an early polybacterial biofilm colonizer, together with concomitant species, known for pro-inflammatory features.

Spring-fen habitat islands in a warming climate: Partitioning the effects of mesoclimate air and water temperature on aquatic and terrestrial biota.

Climate warming and associated environmental changes lead to compositional shifts and local extinctions in various ecosystems. Species closely associated with rare island-like habitats such as groundwater-dependent spring fens can be severely threatened by these changes due to a limited possibility to disperse. It is, however, largely unknown to what extent mesoclimate affects species composition in spring fens, where microclimate is buffered by groundwater supply. We assembled an original landscape-scale dataset on species composition of the most waterlogged parts of isolated temperate spring fens in the Western Carpathian Mountains along with continuously measured water temperature and hydrological, hydrochemical, and climatic conditions. We explored a set of hypotheses about the effects of mesoclimate air and local spring-water temperature on compositional variation of aquatic (macroinvertebrates), semi-terrestrial (plants) and terrestrial (land snails) components of spring-fen biota, categorized as habitat specialists and other species (i.e. matrix-derived). Water temperature did not show a high level of correlation with mesoclimate. For all components, fractions of compositional variation constrained to temperature were statistically significant and higher for habitat specialists than for other species. The importance of air temperature at the expense of water temperature and its fluctuation clearly increased with terrestriality, i.e. from aquatic macroinvertebrates via vegetation (bryophytes and vascular plants) to land snails, with January air temperature being the most important factor for land snails and plant specialists. Some calcareous-fen specialists with a clear distribution centre in temperate Europe showed a strong affinity to climatically cold sites in our study area and may hence be considered as threatened by climate warming. We conclude that prediction models solely based on air temperature may provide biased estimates of future changes in spring fen communities, because their aquatic and semiterrestrial components are largely affected by water temperature that is modified by local hydrological and landscape settings.

Effect of Fascioloides magna (Digenea) on fecundity, shell height, and survival rate of Pseudosuccinea columella (Lymnaeidae).

Infection with Fascioloides magna (Digenea) causes serious damage to liver tissue in definitive hosts represented by ruminants, especially cervids. The distribution of F. magna includes the indigenous areas in North America, and the areas to which F. magna was introduced-Central Europe, Southeast Europe, and Italy. The North American intermediate host of F. magna, the freshwater snail Pseudosuccinea columella (Lymnaeidae), is an invasive species recorded in South America, the Caribbean, Africa, Australia, and west and Southeast Europe. In Europe, Galba truncatula is the snail serving for transmission, but P. columella has potential to become here a new intermediate host of F. magna. Little is known about interactions between F. magna and P. columella. In this study, the susceptibility of P. columella (Oregon, USA) to the infection by a single miracidium of the Czech strain of F. magna and the influence of F. magna on snail fecundity, shell height, and survival were evaluated. The data show that the Oregon strain of P. columella is a highly suitable host for the Czech strain of F. magna, with the infection rate of 74 %. In addition, a negative effect on survival rate of infected snails was recorded only in the late phase of infection. The infection was accompanied by a major reduction in egg mass production and by a decrease in the number of eggs per egg mass. The shell height of infected snails did not significantly differ from that in unexposed controls.