The diversity of annelids in subterranean waters: a case study from Poland

Not all invertebrate groups commonly occur in subterranean waters but annelids live in surface and underground habitats. The annelid species' richness in various underground waters (wells and interstitial and cave waters) and surface streams of Poland was compared, and the habitat preferences for the most frequent species were determined. Until now, 111 annelid taxa (mainly oligochaetes) had been identified in underground waters in Poland, with higher numbers (71) in the interstitial habitat than in stream bottoms (62). The number of species identified in the caves and wells was distinctly lower (54 and 29, respectively). The Correspondence Analysis did not separate the samples from various underground water types into distinct groups, and the distribution of well fauna was especially scattered (in the ordination diagram) because abiotic parameters differ strongly in studied wells. Only three stygobiontic species (Cernosvitoviella parviseta, Enchytraeus dominicae and Trichodrilus moravicus) were related to some caves. The analysis of the available data indicate that to obtain a comprehensive picture of the aquatic fauna in a given country all types of subterranean aquatic habitats should be sampled and taken into account. Moreover, to ascertain the composition of benthic invertebrates in running waters, investigation of the interstitial habitat should also be performed.

Changes in Snowbed Vegetation in the Western Carpathians Under Changing Climatic Conditions and Land Use in the Last Decades

Snowbed vegetation is one of the most sensitive alpine vegetation type to the climate change, because shortened period of snow cover has essential impact on the snowbed environment. We focus on its changes in the Western Tatras, which is a part of the Western Carpathians (Slovakia). The assessment of changes in snowbed vegetation is based on the method of pair comparison. In 2016–2018, we resampled 21 historical phytocoenological relevés of Festucion picturatae and Salicion herbaceae alliances from 1974 and 1976. Historical data include 45 species, while recent data include 50 species. We observed a decrease in the frequency of species characteristic for snowbeds and, on the other hand, an increase in that for strong competitors, especially grasses and small shrubs from adjacent habitats. According to Ellenberg’s ecological indices, there is some increase in temperature and decrease in light ecological factors in snowbed habitats. In S. herbaceae data, a statistically significant increase in the average species number was observed with new species that penetrated from the adjacent habitats. Changes in species composition between historical and recent data are confirmed by Non-metric multidimensional scaling (nMDS) ordination diagram. Linear mixed-effect models showed big variability in factors that have impact on phytodiversity; nevertheless, temperature is the most significant factor.

Synanthropic communities with Dactylis glomerata L. in the Kursk Region

The results of the studies of synanthropic vegetation in Kursk Region (area is 29 800 sq. km), that is located between 50°54′–52°26′ N and 34°05′–38°31′ E, are given. Zonal vegetation is represented by broad-leaved forests on dark-gray forest soils and meadow steppes on chernozems. Synanthropic vegetation was being studied since 2003. 58 relevés were performed in the city of Kursk and few district centers of Kursk Region. The data were treated by IBIS 7.2 software package (Zverev, 2007). Classification is carried out according to Braun-Blanquet approach, the names of the higher syntaxa follow to «Vegetation of Europe…» (Mucina et al., 2016). Ecological conditions, such as soil moisture, richness in mineral nitrogen, light were assessed with the use of average values by H. Ellenberg et al. (1992) ecological scales while hemero­biality with use of average values of N. G. Ilminskikh (1993) ecological scale and processed by IBIS software (Zverev, 2007). As a result, 2 new associations of synanthropic ve­getation were described. Their communities are widely distributed in anthropogenic habitats within the study area. Ass. Arrhenathero elatioris–Dactylidetum glomeratae (Arepieva 2015) ass. nov. et stat. nov. hoc loco (Table 2, relevés 1–35; nomenclature type (holo­typus) is relevé 19 in the paper by L. A. Arepieva (2015: 102, Table 34), it corresponds to relevé 4 ­(author’s number — 37) in Table 2 in this article) refers to the alliance Convolvulo arvensis–Agropyrion repentis Görs 1967, order Agropyretalia intermedio–repentis T. Müller et Görs 1969, class Artemisietea vulgaris Lohmeyer et al. in Tx. ex von Rochow 1951. Diagnostic species are Arrhenatherum elatius and Dactylis glomerata. Two variants are distinguished within the association. Communities of var. typica (Table 2, rele­vés 1–19; Fig. 1) are described on sunny sites. Communities of var. Glechoma hederacea (Table 2, relevés 20–35; Fig. 2) are often formed in partially shaded habitats under strong anthropogenic impact, that’s why species of the order Arctio lappae–Artemisietalia­ ­vulgaris Dengler 2002 and the class Sisymbrietea Gutte et Hilbig 1975 are more common there. Previously (Arepieva, 2015) we considered this association decribed in the Kursk city as subass. Convolvulo arvensis–Elytrigietum repentis Felföldy 1943 dactylidetosum glomeratae Arepieva 2015. Presently, its rank is rised up to the аssociation for the following reasons: this syntaxon has a wide area of distribution, as the studied communities are common throughout the region, and it good enough differs of the other syntaxa of the alliance Convolvulo arvensis–Agropyrion repentis that are known in our region. Synoptic table (Table 3), value ranges of ecological factors for аssociations (Fig. 3) and DCA-ordination diagram (Fig. 4) demonstrate the differentiation of the syntaxa. The differences of this аssociation of those close to it in composition known in other regions (ass. Convolvulo arvensis–Elytrigietum repentis in Czech Republic, ass. Agropyro repentis–Dactylidetum glomeratae Ubaldi 1976 em. Ubaldi, Puppi et Speranza 1983 in Italy, ass. Geranio tuberosae–Dactylidetum Korzh. et Kljukin 1990 in Ukraine) are discussed. Among syntaxa of the meadow vegetation the most similar in species composition to it is subass. Arrhenatheretum elatioris dactylidetosum glomeratae Nowiński 1967 (alliance Arrhenatherion elatioris Luquet 1926, order Arrhenatheretalia elatioris Tx. 1931, class Molinio-Arrhenatheretea Tx. 1937) in Poland. The syntaxon differentiations are shown in Table 4. In Kursk Region close to the described association is ass. Anthoxantho–Agrostietum tenuis Sillinger 1933 (alliance Cynosurion cristati Tx. 1947, order Arrhenatheretalia elatioris Tx. 1931, class Molinio-Arrhenatheretea Tx. 1937). Ass. Glechomo hederaceae–Dactylidetum glomeratae ass. nov. hoc loco (Table 2, relevés 36–58; nomenclature type (holotypus hoc loco) — relevé 41 (author’s number — 650); Fig. 5) belongs to the alliance Arction lappae Tx. 1937, order Arctio lappae–Artemisietalia vulgaris Dengler 2002, class Epilobietea angustifolii Tx. et Preising ex von Rochow 1951. Diagnostic species are Carex contigua, Dactylis glomerata, Elsholtzia ciliata, Glechoma hederacea, Xantho­xalis stricta. Its communities, that occur in parks and gardens, were described in shaded habitats. The differences between this association and those of synanthropic vegetation close to it in the species composition are shown: ass. Leonuro–Arctietum tomentosi Lohmeyer in Tx. 1950 in Kursk Region and ass. Arctio tomentosi–Rumicetum obtusifolii Passarge 1959 in Slovakia (Table 5; Fig. 6, 7). Identified syntaxa, described within different orders and classes, have high floristic similarity because their communities are directed series with gradually changing conditions (the DCA-ordination diagram on Fig. 8). There is a change of impact of some ecological factors (light, moisture, reaction and richness in mineral nitrogen of soils and substrates) along axis 1. On this axis the communities of var. Glechoma hederacea of the ass. Arrhenathero elatioris–Dactylidetum glomeratae occupy an intermediate position and species, that have high constancy in ass. Glechomo hederaceae–Dactylidetum glomeratae, also occur in these. In all likelihood, the axis 2 is a change in degree of anthropogenic impact, which does not significantly influence on the syntaxon differentiation. The results of DCA-ordination are confirmed by the value ranges of ecological factors (Fig. 9).

Morphological Variation and Speciation of Acavidae Family: A Case Study from Fossil and Living Species of Batadombalena Cave Pre-historic Site in Sri Lanka

A sufficient knowledge on prehistoric culture and habitat of earliest Homo sapiens (Balangoda man) is available in Batadomba-lena cave, a noticeable rock shelter in lowland rainforest of southwestern Sri Lanka goes upto Pleistocene and Holocene eras. Late Pleistocene inhabitants of Batadombalena cave’s foraged for a broad spectrum of plant and mainly arboreal animal resources such as, monkeys, squirrels and rainforest snails etc. Archaeo-faunal evidence would help to describe the prehistoric man eating behavior as well as availability of nature pre-historic flora, fauna and environmental status. The family Acavidae is very sensitive to climatic variations, hence used as a bio-indicator to describe the variations of paleo-climatic nature. This study examined the morphological features of 20 samples of Acavidae family (living/fossil samples of Acavus superbus, and sub fossil samples of Oligospira waltoni) collected from soils by digger method in 2005 and compared with 20 samples from the same area at presently available. The shell characters of snails such as, height, width, diameter of mouth, thickness of lip, and angular of axis were measured and subjected to multivariate analysis to understand how climatic variability and nature of paleo-diet contribute survival of Acavidae species. Results showed that Acavus superbus living species had large shell characteristics than the sub fossils. Results of similar study in the same climatic status in 2000 showed that the shell measurements of Acavus superbus are relatively larger than both living and sub fossils in Batadobalena cave. Ordination diagram derived from species shell characteristics showed that Acavus superbus living species grouped as scattered /diffuse clusters, while sub fossil species grouped as a single cluster at the center of the ordination diagram. It is imply a trend of speciation /diversification of Acavus species from Pleistocene era to date. Multivariate analyses prove that, a strong positive correlation of species characteristics, such as height (r = 0.62), thickness of lip (r = 0.544) and angular of axis (r = 0.744), and a strong negative relationship (r = 0.832) for shell width for the species were observed. Our results are useful to compare with other fossil snails to see whether the climate change influence for changing body size. In conclusion, palaeo-environment, and present environment variation has been occurred in minimum way without much changes to observed Acavidae species compositions present and past.

Prevalence of honeybee viruses in the Czech Republic and coinfections with other honeybee disease

Six bee viruses, which occur in Apis mellifera, were monitored in the Czech Republic between 2006 and 2009. Samples of larvae and pupae collected from hives where American foulbrood was detected were screened for bee viruses and in the 125 samples of larvae, there was no confirmed case of a larva infected with both American foulbrood and a bee virus. Of 145 samples infected with the protozoan Nosema apis, there were 23 cases of coinfections with the BQCV virus, 18 with the DWV virus and 11 with the ABPV virus. All coinfections with three or four viruses were also statistically significant apart from the one between ABPV with CBPV and DWV. The PCA ordination diagram indicates that BQCV occurs mainly with Nosema apis and DWV mainly with ABPV.

Environmental Factors Influencing the Distribution of Juvenile Groundfish in Nearshore Habitats of Southwest Nova Scotia

Eight nearshore (< 20 m) marine habitats were surveyed to estimate the relative abundance of juvenile groundfish and to assess the environmental variables influencing their distribution. Surveys were conducted as part of a depth-stratified, random sampling design; at each site a small otter trawl was towed for 15 min at eight stations in each of three depth strata. A suite of 13 environmental variables were measured in association with each tow. A total of 1908 fish from 13 different species were caught at 191 completed trawl stations. Standardized centered principal components analysis, orthogonally rotated factor analysis, and detrended correspondence analysis (DCA) were used to delineate aggregations in the abundance data. DCA coupled with stepwise multiple regression best resolved the species' distributions and dominant gradients in the environment. The first two DCA axes reflected estuarine to coastal gradients (68% of the variance) and significant environmental variables were plotted as vectors in the ordination diagram. An estuarine assemblage of species, characterized by winter flounder (Pseudopleuronectes americanus) and white hake (Urophycis tenuis), was associated with waters that were warmer, less saline, more turbid, and overlying a finer grained substrate, than a coastal assemblage of species which included cod (Gadus morhua) and rock gunnel (Pholis gunnellus). The biologically significant gradients corresponded to those which dominated variation in the physical environment.