Search Results (62)

The Ukrainian brook lamprey (UBL) (Eudontomyzon mariae) spreads in Poland and often replaces the European brook lamprey (EBL) (Lampetra planeri) in rivers contaminated by wastewater effluents. We aimed to investigate whether this phenomenon is associated with differences in the intestinal microbiota of the two lamprey species. We analysed seasonal changes in the midgut microbial content of the UBL ammocoetes collected from a section of the River Gać affected by wastewater treatment plant effluent. The numbers of cultivable psychrophilic (autochthonous) and mesophilic (allochthonous) microorganisms, along with Escherichia coli and faecal streptococci, were compared to those found in the EBL from the same site. Higher levels of the faecal indicator microorganisms were observed in the UBL gut content compared to the EBL across most seasons, particularly in the winter (all mesophiles), in contrast to the levels of psychrophilic bacteria. This may suggest a relatively greater accumulation of mesophilic, sewage-associated bacteria in the UBL gut. Varying intestinal bacterial counts in the UBL gut did not reflect trends observed for the microorganisms in surrounding water during the studied seasons. These findings support the hypothesis that the UBL potentially benefits from the uptake of faecal bacteria. Such adaptation may contribute to its dominance in contaminated freshwater ecosystems, where EBL populations decline. Full article

Thanks to their striking shapes and colors, heterobranch “sea slugs” are probably the most sought-after group of marine critters by scuba divers around the world. Nevertheless, for many of the islands and coasts of Sicily, there are no specific studies on the fauna of this group (formerly known as opisthobranchs). Even Lampedusa, one of the most famous islands in the Mediterranean, is no exception to this. To fill this knowledge gap, the authors conducted a faunal study dedicated to this group in July 2025. Data collection, carried out using the photographic-capture technique both during scuba diving and snorkeling, led to the finding of 22 species of heterobranch “sea slugs”. A comparison of the heterobranch “sea slugs” of Lampedusa with that of other Sicilian islands revealed a low diversity of these mollusks on this island. This scarcity of fauna is probably due to the lack of favorable environments and the considerable environmental homogeneity that characterizes the seabed and coastal areas of Lampedusa. Nevertheless, the discovery of some species of considerable biogeographical importance, together with the island’s unique geographical position, make it an important location to monitor for the study of the distribution patterns of allochthonous marine Heterobranchia species that enter into the Mediterranean Sea. Full article

The Danube in Croatia serves as an important transport route but also favors the spread of invasive species, especially in the floodplain areas. Many of them originate from the Ponto-Caspian region and influence European ecosystems with their migrations. One of these species, Limnomysis benedeni, a mysid shrimp, thrives in shallow waters and plays a crucial role as a food source for fish. L. benedeni was first recorded in Croatia in 2004 in Lake Sakadaš (Kopački Rit). Prior to the study on aquatic macroinvertebrates in Kopački Rit Nature Park, conducted from July 2020 to July 2023, there had been no documented records in recent years. Sampling was carried out seasonally for macroinvertebrates and monthly for environmental parameters at 15 sites within the park or in the immediate vicinity. Samples were collected according to standard AQEM methodology. A total of 21 macroinvertebrate groups (407 taxa), out of which the most diverse were Diptera with 20 families, were identified in this study, including nine allochthonous species in addition to L. benedeni. The most abundant populations of L. benedeni were found in the Danube, the Petreš channel, and Vemeljski Dunavac channel, which supply the floodplain with water from the Danube. Most individuals were collected in summer and spring, with the highest density being 741 individuals per square meter. Environmental parameters such as water level, type of habitats, pH values, chemical oxygen demand, and phosphorus content, were statistically significant for the distribution of species. The dominant microhabitat for L. benedeni in Kopački Rit was argyllal in combination with coarse particulate organic matter and wood debris, and the composition of these microhabitats remained consistent throughout the seasons. L. benedeni was the only crustacean species to establish a stable population in the floodplain area, excluding Asellus aquaticus (water louse), a cosmopolitan species. The ongoing influence of L. benedeni on the native community still remains to be determined. Full article

Coastal wetlands provide vital ecosystem services, yet large-scale removal of invasive Spartina alterniflora disrupts soil carbon pools and fragments habitats. Converting this biomass to biochar may enhance restoration outcomes, though ecological effects remain poorly understood. We evaluated how Spartina alterniflora-derived biochar (0%, 0.5%, 1%, and 3%) influences growth performance, clonal reproduction, root morphology, and rhizosphere properties of native Scirpus mariqueter. Moderate biochar addition (1%) significantly boosted plant performance, increasing total biomass by 64.5%, aboveground biomass by 36.7%, and belowground biomass by 115.0%, while root length increased by 135.8%. Biochar improved soil moisture and nutrient availability, including nitrate nitrogen (NO₃⁻-N), ammonium nitrogen (NH₄⁺-N), and available phosphorus (AP), while stimulating nitrification and promoting clonal propagation. In contrast, high-dose biochar (3%) elevated soil salinity and electrical conductivity, leading to suppressed plant growth and reproductive allocation. Correlation analysis revealed strong positive associations between root volume and soil nutrient levels. Our findings demonstrate that moderate application of Spartina alterniflora-derived biochar enhances plant productivity and soil function, potentially improving carbon sequestration in restored coastal wetlands. This study provides insights into ecological recycling of invasive biomass and supports biochar as a viable tool for sustainable wetland restoration, though potential risks at high concentrations warrant further investigation. Full article

The structure and density of plankton communities greatly influence carbon and nutrient cycling as well as the environmental status of lake ecosystems. This community can respond to a range of environmental drivers, including those influenced by human perturbations on local and regional scales, causing abrupt changes and imbalances. While the implications of climate and land-use changes are evident for a range of tropical lake conditions, their impacts on planktonic population dynamics are less understood. In this study, we aimed to investigate how distinctive levels of nutrients, allochthonous organic matter (OM), and sunlight availability change phytoplankton and zooplankton density and structure in a natural tropical lake. Using an in situ mesocosm facility, we manipulated the addition of nutrients and OM, in addition to sunlight availability and a combination of these treatments. We monitored limnological parameters, plankton count, and identification for 12 days. The mesocosms included eight different combinations in a 2 × 2 × 2 factorial design, each with two replicates. Inorganic nutrient addition reduced phytoplankton species richness, favoring the dominance of opportunistic species such as Chlorella sp. at much higher densities. Organic matter also increased light attenuation and caused the substitution of species and changes in dominance from Pseudanabaena catenata to Aphanocapsa elachista. On the other hand, physical shading had less influence on these communities, presenting densities similar to those found in the control mesocosms. Zooplankton presented a group dominance substitution in all mesocosms from copepod to rotifer species, and copepod growth seemed to be negatively affected by Chlorella sp. density increase. Furthermore, this community was associated with the light attenuation indices and bacterioplankton. These results indicate that tropical planktonic responses to environmental changes can effectively occur in just a few days, and the responses can be quite different depending on the nutritional source added. The punctual nutrient addition was sufficient to provide changes in this community, evidencing the strength of anthropic events associated with strong nutrient input. Understanding tropical plankton dynamics in response to environmental changes, such as those simulated in this work, is important for understanding the effects of climate and anthropogenic changes on tropical lake functioning. This knowledge can strengthen measures for the conservation of freshwater systems by allowing predictions of plankton community changes and the possible consequences for the aquatic food chain and water quality. Full article

Urban flora is a more and more interesting research subject, in light of the ongoing environmental change and biological homogenisation, since urban contexts are much more diversified that natural ones and, therefore, they offer much more colonisation possibilities to allochthonous species or unexpected refuges for endangered species. We have, therefore, added our own contribution by analysing the spontaneous vascular flora of 7 cities of the Emilia-Romagna Po Plain (northern Italy), one of the more culturally and economically developed areas in Europe. The global floristic list was 1305 species, spanning from 432 to 756 species in each individual city; 219 of them were constantly present in all cities examined. A notable richness in phytosociological classes (43 out of 75 known for the entire national territory) was observed. Therophytes were 35.4% of the spectrum, followed by hemicryptophytes, phanerophytes and geophytes. Eurasian and Mediterranean species dominated (average values 30 and 27%, respectively); exotic species were 26.8%, in line with the strong floristic pollution of Emilia-Romagna, with neophytes always prevailing over archaeophytes. Among neophytes, 44.8% came from the Americas and 26.2% from Asia. Some hydro-hygrophilous and halophilous species were found, owing to the presence of watercourses crossing the urban areas and coastal wetlands bordering one of the towns. The species new for the flora of Italy or Emilia-Romagna were 32, of which 24 were allochthonous. The species protected at a regional or national level were hardly present, which is normal in artificial environments. Despite the inevitable differences in exploration intensity and effort, this synthesis offers a picture of the contribution given by anthropogenic habitats to the global biological richness of the territory. Full article

Rhamdiopsis krugi is a highly specialized troglobitic (exclusively subterranean) catfish endemic to the phreatic water bodies of twelve caves located within two separated metasedimentary basins in the region of Chapada Diamantina, Bahia state, Brazil. This species is included in the List of Endangered Fauna of Brazil, under the Vulnerable category—VU. In general, troglobites have different strategies for searching for food and reproductive partners, as well as unique behaviors. Knowledge of the reproductive periods, as well as its feeding habits, provides fundamental data for effective protection and species conservation. Biological aspects related to feeding habits and reproduction of R. krugi were addressed across six annual cycles, considering both dry and rainy seasons. For this, stomach content analysis, using the frequency of occurrence and volumetric index methods, as well as observation of the sex ratio and stage of maturation of the gonads were carried out for 148 individuals of R. krugi sampled in eight caves in Chapada Diamantina. Stomach volumes correlated with reproduction aspects across the dry and rainy seasons. These populations showed opportunistic carnivorous feeding habits, consuming both autochthonous and allochthonous items, with a preference for foraging in submerged guano deposits, which demonstrates the catfish’s strong dependence on bats. Regarding sex ratios, there was no marked seasonality; however, in rainy seasons, there was a higher proportion of maturing females, showing a reproductive tendency. During these periods, there was also a significantly higher number of stomachs with contents, showing seasonality in the diet. Specialized diet and dependence on rainy periods, especially in diet, corroborate the fragility of R. krugi, especially considering the changes in rainfall regimes in Brazil, with dry seasons exceeding eight months per year in the last ten years. Full article

The fish fauna of Rio de Janeiro has been extensively studied, resulting in a comprehensive database of species collected over more than three centuries. This study aimed to provide a checklist of species, to identify patterns of diversity and the distribution of freshwater ichthyofauna, to delineate biogeographic units, and to explore changes in faunal composition among different areas. Analyzing data from ichthyological collections and the literature on original species descriptions revealed 206 freshwater fish species: 183 native and 23 allochthonous. The checklist includes updated species names. The sampling effort in Rio de Janeiro is extensive, especially in coastal lowlands. The findings indicate that inventory work is still needed in some areas, particularly within the Rio Paraíba do Sul basin. Seven bioregions of freshwater ichthyofauna were identified, including a major region of higher species richness and smaller areas with higher endemism of restricted-range species. This biogeographic assessment underscores the diverse and distinctive freshwater fish fauna in the basins of Rio de Janeiro, with well-defined biogeographic units. Full article

In this study we focused on the need to fill a knowledge gap among Italian botanical studies namely that of ornamental species census. In particular, we addressed one of the regions in southern Italy with less knowledge in the field of such studies and with an obvious presence of non-native species. A widespread census of the Apulian territory was carried out between 2021 and 2024 in both urban and suburban areas including street trees, parks, and private and historic gardens. The inventory of ornamental trees, shrubs, and succulents of Apulia (southern Italy) was carried out in six provinces, i.e., Bari, Barletta-Andria-Trani, Brindisi, Foggia, Lecce, and Taranto. The checklist comprises 287 taxa (including 265 species, 6 varieties, 5 subspecies, and 11 forms) included in 179 genera belonging to 78 families. We evaluated the number of taxa per families and genera, the presence of each taxa in the provinces of Apulia, the number of taxa per occurrence status, growth forms, geographical origin, and the number of native and alien taxa and also the artificial hybrids. Remarks of the most significant taxa and evaluation of geographical distribution in Italy were also taken into consideration. A large number of surveyed taxa (51.74%) are comprised in the list reported in the recent study on allochthonous vascular flora in Italy with a marked prevalence of Neophyte Casual Alien and Neophyte Naturalized Alien species. Full article

Fresh, green leaves are increasing as resources in aquatic ecosystems due to more frequent severe spring and summer storms, but research on allochthonous resources typically uses senescent leaves. We examined macroinvertebrate colonization of green leaves of three native deciduous trees (red maple, red oak, and tulip poplar) over two weeks within both a stream and fishless pond. Leaf colonization varied depending on the taxa of leaves and colonizers, submersion time, and the ecosystem examined. Within the stream, the densities of isopods (Lirceus sp.) and snails (mostly the invasive Potamopyrgus antipodarum) did not vary significantly across leaf species. In contrast, mayflies (Tricorythodes sp.) in the stream colonized tulip poplar in greater numbers than red oak leaves, while higher densities of planarians (order Tricladida) occurred within red oak leaves. The numbers of mayflies and snails decreased significantly by the second week, but the densities of isopods and planaria within stream leaf packs were consistent. In contrast, within the pond, significantly more isopods (Caecidotea communis) were collected after the first than after the second week of submersion and in tulip poplar leaves. Clams (Sphaeriidae) in the pond, on the other hand, were more prevalent in the second week but did not discriminate among leaf species. While the number of leeches (mostly Helobdella stagnalis) was consistent across weeks, significantly fewer leeches resided within tulip poplar leaves than within red oak leaves. Our results suggest that there are no consistent colonization-preference rankings of species of fresh leaves across freshwater benthic macroinvertebrate taxa. Even within a functional feeding group (e.g., the two types of isopods and snails, all detritivore-herbivores), there were differences in colonization patterns. Therefore, increased allochthonous inputs of fresh leaf litter due to severe spring- and summer-time storms are likely to promote the populations of various taxa to different extents. Full article

Subterranean environments are often characterized by a natural gradient of microclimatic conditions and trophic resources, showing a higher trophic availability and a lower microclimatic stability in the shallowest area (close to the cave entrance), while the opposite occurs in the deepest sections. The shallowest areas of subterranean environments (e.g., the entrance and twilight zone, Mesovoid Shallow Substratum) act as ecotones between the surface habitats and the deep areas, creating a particular habitat which can be exploited by numerous species with different degrees of adaptation to subterranean environments. Species living in these ecotones may hold a key role in sustaining the entire ecosystem, as they are likely one of the major drivers of allochthonous organic matter. Indeed, these species are usually facultative cave-dwellers, meaning that they are able to exit and forage on the surface. Once these species are back inside the cave, they provide the local community with different typologies of organic matter (e.g., feces, eggs), which represent one of the most important sources of organic carbon. Therefore, studying which ecological features may exert significant effects on the abundance of these species may be of great help in understanding the ecosystem dynamics and the functional role of each species. In this study we analyzed the data collected through a year-round monitoring program, aiming to assess the potential effects that both abiotic and biotic features may have on the abundance of three facultative cave species. We focused on seven caves located in Monte Albo (Sardinia, Italy). The cave environments were divided into 3-meter sectors, and within each cave sector, microclimatic and biological data were seasonally recorded. We focused on the following facultative cave species: the spiders Metellina merianae and Tegenaria sp. and the snail Oxychilus oppressus. Different relationships were observed between the ecological features and the abundance of the three species. The two spiders were more abundant in warmer cave sectors closer to the cave entrance, especially the M. merianae. On the other hand, the snail tended to be more abundant farther from the cave entrance and in more illuminated cave sectors, probably because sunlight promotes the abundance of some of its trophic resources (e.g., lichens, vegetation). Furthermore, O. oppressus was the only species whose abundance and cave distribution was significantly affected by seasonality. This study provides useful and novel information to understand the population dynamics of facultative cave species and their role in subterranean ecosystems. Full article

Cuba is struggling with a growing environmental problem: the uncontrolled spread of the allochthonous weed species marabou (Dichrostachys cinerea) throughout the country. Over the last 70 years, marabou has become a formidable invasive species that poses a threat to Cuban biodiversity and agricultural productivity. In this paper, we present a free and affordable method for regularly mapping the spatial distribution of the marabou based on the Google Earth Engine platform and ecological surveys. To test its accuracy, we develop an 18-year remote sensing analysis (2000–2018) of marabou dynamics using the Valle de los Ingenios, a Cuban UNESCO World Heritage Site, as an experimental model. Our spatial analysis reveals clear patterns of marabou distribution and highlights areas of concentrated growth. Temporal trends illustrate the aggressive nature of the species, identifying periods of expansion and decline. In addition, our system is able to detect specific, large-scale human interventions against the marabou plague in the area. The results highlight the urgent need for remedial strategies to maintain the fragile ecological balance in the region. Full article

The release of oil into the environment represents a pervasive problem stemming from oil exploration, accidents, transportation and releases from landfills, storage facilities or industrial plants. Compared to conventional and costly techniques, bioremediation is an attractive and promising alternative, as it can selectively degrade pollution without affecting the natural features of the site and the flora and fauna living there. In this study, the isolation, identification and characterization of autochthonous bacterial strains from a crude oil-contaminated soil sample was carried out under batch conditions over a period of 28 days. The initial colony forming units value for bacteria was 1.15 × 10⁹/g of soil. The results show that the activity of bacteria was highest at a pH of 7.25. Based on morphology, biochemical tests and an analysis of MALDI TOF, isolated autochthonous bacterial species were identified as Bacillus megaterium, Bacillus licheniformis, Bacillus cereus and Pseudomonas chlororaphis. Since allochthonous bacteria are not highly efficient in a new environment due to their low adaptability and competition with indigenous microorganisms, these autochthonous microorganisms play a pivotal role in enhancing the bioremediation process on an applicable, industrial scale. This advancement aligns with the principles of sustainable development and the green economy, as purified soil is suitable for rational reuse in the environment. Full article

Knowledge of native Arbuscular Mycorrhizal Fungi (AMF) and their relationship with the edaphic characteristics where they live is important to establish the influence of allochthonous AMF, which were inoculated, on the development and stability of soil aggregates. The objectives of this research were to know the composition of native AMF species from two contrasting soils, and to establish the development and stability of aggregates in those soils with corn plants after inoculating them with allochthonous AMF. The experiment had three factors: Soil (two levels [S1 and S2]), HMA (three levels: without application [A0], with the application of Claroideoglomus claroideum [A1] and with the application of a consortium [A2]) and Fertilization (two levels (without fertilization [f0] and with fertilization [f1])). Twelve treatments were generated, with five replicates (60 experimental units [EU]). The EU consisted of a pot with a corn plant and the distribution was completely random. The results demonstrated that the Typic Ustifluvent presented nine species of native AMF, while the Typic Dystrustert had three; the native AMF in each soil influenced the activity of allochthonous AMF, such as their colonization and sporulation. Likewise, differences were found in the stability of macro-sized aggregates (0.5 to 2.0 mm). Full article

We here provide the first comprehensive analysis and discussion on prey consumed by the European cave salamanders of the genus Speleomantes. Our study stems from the need to shed light on the still unknown foraging behavior adopted by Speleomantes cave salamanders. Starting from the published datasets on gut contents from all Speleomantes species (including hybrids), we here discuss additional information (i.e., species ecology, lower taxonomic level), which were systematically omitted from those data sets. We analyzed a data set consisting of 17,630 records from 49 categories of consumed prey recognized from gut contents of 2060 adults and juveniles Speleomantes. Flying prey accounted for more than 58% of the prey items, while elongated crawling prey accounted for no more than 16% of the diet within a single population. Among the total recognized prey items, only three can be surely ascribed to the group of strictly-cave species (i.e., troglobites), meaning that European cave salamanders mostly forage in surface environment, and therefore represent one of the major drivers of allochthonous organic matter in subterranean environments. Some of the consumed prey seemed to be aquatic, allowing us to hypothesize whether Speleomantes are able to catch prey from a shallow body water. Furthermore, European cave salamanders possess the ability to prey upon taxa characterized by particular anti-predator defenses, while morphological constraints seem to be the most important limit to prey consumption. For each specific case, we provide insights and propose hypotheses concerning the foraging behavior that need to be tested to properly understand the foraging behavior of this cryptic salamanders. Full article