146 research outputs found
Peculiarities of the Accumulation of Mineral Elements and Nitrogen in the Assimilation Apparatus of Scots Pine
The research has been carried out in the Arkhangelsk forestry of the Arkhangelsk Region in a drained shrub-sphagnum pine forest. Census trees of medium diameter and height for the stand have been selected, from which samples of needles, both living and dying yellow ones, and shoots of different ages have been taken on model branches. Soil samples have also been taken from the 3 upper horizons. It has been established that most of all nitrogen and mineral elements accumulate in the living needles – 4.4 % on average, in the dying needles and shoots there are 37–40 % less. Among all the elements, nitrogen, potassium and calcium make up the largest proportion; while the rest of the chemical elements are several time less. In descending order of the share, they are arranged in the following sequence: magnesium, sulfur, phosphorus, manganese, silicon, iron and aluminum. The most important mineral elements are derived in significant quantities from the dying yellow needles. The content of sulfur, magnesium, phosphorus, manganese and iron decreases in them by 3.3, 2.1, 8.0, 1.5 and 1.4 times, respectively, compared to the living needles. Data on the presence of nitrogen and mineral elements in the soil horizons A0, T1 and T2 have been obtained. It has been established that some of the essential elements for the life of a tree are concentrated in the living needles in much larger quantities than in the soil: potassium, phosphorus, manganese and calcium – by 12.0, 4.0, 6.0 and 1.9, respectively. The yellow falling needles create a biological cycle of substances. The amount of nitrogen and ash constituents in these needles is proportional to their presence in the soil. In turn, the content of mineral elements in the shoots is close to their amount in the yellow falling needles, on the one hand, and on the other, depends on the age of the shoots. There is a steady trend of decreasing the content of nitrogen, potassium, phosphorus and sulfur with the age of the shoots
Widespread continental mtDNA lineages prevail in the bumblebee fauna of Iceland
Origins of the fauna in Iceland is controversial, although the majority of modern research supports the postglacial colonization of this island by terrestrial invertebrates rather than their long-term survival in glacial refugia. In this study, we use three bumblebee species as a model to test the hypothesis regarding possible cryptic refugia in Iceland and to evaluate a putative origin of recently introduced taxa. Bombus jonellus is thought to be a possible native Icelandic lineage, whereas B. lucorum and B. hortorum were evidently introduced in the second half of the 20th century. These phylogeographic analyses reveal that the Icelandic Bombus jonellus shares two COI lineages, one of which also occurs in populations on the British Isles and in mainland Europe, but a second lineage (BJ-02) has not been recorded anywhere. These results indicate that this species may have colonized Iceland two times and that the lineage BJ-02 may reflect a more ancient Late Pleistocene or Early Holocene founder event (e.g., from the British Isles). The Icelandic populations of both Bombus lucorum and B. hortorum share the COI lineages that were recorded as widespread throughout Eurasia, from the European countries across Russia to China and Japan. The findings presented here highlight that the bumblebee fauna of Iceland comprises mainly widespread ubiquitous lineages that arrived via natural or human-mediated dispersal events from the British Isles or the mainland
Review of the globally invasive freshwater mussels in the genus Sinanodonta Modell, 1945
In this review, we synthesize the current knowledge of the biology, ecology, and impact of Sinanodonta freshwater mussels (Bivalvia, Unionidae), native to East Asia, that have successfully invaded Europe, Central America, North Africa, and several Asian regions. The main introduction pathways of Sinanodonta were reconstructed based on DNA sequence data and distribution records. We show that invasive lineages of Sinanodonta belong to three species, namely, S. woodiana s. str. (“temperate invasive” lineage), S. pacifica (“tropical invasive” lineage), and S. lauta. Their generalist fish-dispersed larvae, short life span, high fecundity, use by humans for multiple purposes, and ability to establish populations in anthropogenically disturbed conditions were identified as crucial traits driving their invasions. Information on the consequences is scarcer, but Sinanodonta can impact native species through larval parasitism, host fish/food competition, and parasite transmission. In addition, ecosystem effects through their filtration—biodeposition—excretion activity and the occurrence of massive die-offs were detected. Ecosystem services and disservices have not yet been quantified, even at local scales, and management methods in the invasive range are understudied. A better understanding of Sinanodonta ecology, impacts, and management options is urgently needed to make informed decisions and set realistic and impactful restoration goals
Complete mitochondrial genomes of the freshwater mussels Amblema plicata (Say, 1817), Pleurobema oviforme (Conrad, 1834), and Popenaias popeii (Lea, 1857) (Bivalvia: Unionidae: Ambleminae)
Freshwater mussels are a critically imperiled group of mollusks that play key ecological roles and provide important services to humans. The Ambleminae is the only subfamily of these mussels, endemic to North America. Complete mitogenomes have only been sequenced for two of five tribes of the subfamily. Pleurobema oviforme, Amblema plicata, and Popenaias popeii each belong to tribes Pleurobemini, Amblemini, and Popenaidini, respectively, and have not had published mitogenomes. Thus, this study aims to present the complete mitogenomes for these species, to provide a phylogeny of the Ambleminae and confirm the gene arrangements with representation from each of its tribes. The newly sequenced mitogenomes range from 15,852 to 15,993 nucleotides, are composed of 13 PCGs, 22 tRNAs, and two rRNAs and all share the same (UF1) gene order.This work was supported by Portuguese Foundation for Science and
Technology (FCT) [grant number ConBioMics/BI-Lic/2019-037 (JTT), grant
number SFRH/BD/137935/2018 (AGS)]; COMPETE 2020, Portugal 2020
and the European Union through the ERDF, and by Portuguese
Foundation for Science and Technology (FCT) through national funds
[UID/Multi/04423/2019] under project ConBiomics: the missing approach
for the Conservation of Bivalves Project, and [project number NORTE-01-
0145-FEDER-030286]. Fieldwork in Texas was funded by the U.S. Fish and Wildlife Service, and Texas Parks and Wildlife Department (TPWD) as a Joint Traditional Section 6 Project 407348.info:eu-repo/semantics/publishedVersio
Trace Element Patterns in Shells of Mussels (Bivalvia) Allow to Distinguish between Fresh- and Brackish-Water Coastal Environments of the Subarctic and Boreal Zone
The accumulation of trace metals in the shells of bivalves allows quantitative assessments of environmental pollution and helps to reconstruct paleo aquatic environments. However, the understanding on how marine and freshwater mollusks control the level of trace elements in their shells remains very limited. Here, we compared the trace element composition of marine and freshwater bivalves from boreal and subarctic habitats, using examples of widely distributed species of marine (Mytilus edulis, M. trossulus) and freshwater (Anodonta anatina, Unio sp., Beringiana beringiana) mussels. Sizable differences in several trace element concentrations were detected between different species, depending on their environmental niches. A multiparametric statistical treatment of the shell’s elemental composition allowed to distinguish the impact of external factors (water and sediment chemical composition) from active metabolic (biological) control. In particular, the obtained results demonstrated that Ba:Ca and Pb:Ca ratios in mussels’ shells are closely related to the primary productivity of aquatic ecosystems. The Mn:Ca ratio allowed to constrain the environmental conditions of mussels’ species depending on the trophic state of inhabited waterbody. Overall, the marine mussels exhibited stronger biological control of trace element accumulation, whereas trace element pattern in shells of freshwater mussels was chiefly controlled by environmental factors. The obtained results might help to use the trace element composition of bivalves in distinguishing marine and freshwater habitats of mollusks in paleo environments
An example of a possible leech-bryozoan association in freshwater
Associations of various invertebrate species with bryozoans and sponges are a well-known marine phenomenon but such epizooic communities are far less diverse in freshwater environments. Here an occurrence of numerous leeches Alboglossiphonia cf. papillosa (Braun, 1805), in interstitial spaces between zooids of a colony of the freshwater bryozoan species Plumatella aff. fungosa (Pallas, 1768) in Eastern Siberia is described. To the best of our knowledge, this record appears to be the first known example of a leech-bryozoan association, although such relationships deserve further research
Conbiomics: the missing approach for the conservation of freshwater bivalves
The decline of freshwater biodiversity hás reached alarming proportions. The
extinction rate of freshwater biodiversity is predicted to be five times faster than ali
other groups of species. The Unionidae, being the largest of the freshwater bivalve
families, is among the most endangered group in the world. They are important
providers of aquatic ecosystem services and are characterized by an unusual
pattem of mtDNA inheritance. However, phylogeny, population genetic structure
and species-level diversity remains unclear for much of the group. With an
experienced and well-qualified team, the present proposal aims to define the most
important freshwater mussel taxa and most criticai áreas for conservation, at
European and Global leveis, to inform the most relevant policy niakers. This will be achieved by integrating a genomics approach with available distribution data, in order to determine and map global species richness, phylogenetic diversity, and weighted endemism. This complementary approach will not only help conserve this vulnerable group but will offer wider benefits to freshwater ecosystems whose billions of people depend globally. Additionally, as these animals have an extraordinary unusual pattern of mtDNA inheritance, they will be used as model-taxa to study the evolution of mtDNA and life in general.This research was developed under Project NÂş NORTE-01-0145-FEDER-030286 (ConBiomics: the missing approach for the Conservation of freshwater Bivalves), co-financed by COMPETE 2020, Portugal 2020 and the European Union through the ERDF, and by FCT through national funds.info:eu-repo/semantics/publishedVersio
Freshwater mussel conservation: A global horizon scan of emerging threats and opportunities
We identified 14 emerging and poorly understood threats and opportunities for addressing the global conservation of freshwater mussels over the next decade. A panel of 17 researchers and stakeholders from six continents submitted a total of 56 topics that were ranked and prioritized using a consensus-building Delphi technique. Our 14 priority topics fell into five broad themes (autecology, population dynamics, global stressors, global diversity, and ecosystem services) and included understanding diets throughout mussel life history; identifying the drivers of population declines; defining metrics for quantifying mussel health; assessing the role of predators, parasites, and disease; informed guidance on the risks and opportunities for captive breeding and translocations; the loss of mussel-fish co-evolutionary relationships; assessing the effects of increasing surface water changes; understanding the effects of sand and aggregate mining; understanding the effects of drug pollution and other emerging contaminants such as nanomaterials; appreciating the threats and opportunities arising from river restoration; conserving understudied hotspots by building local capacity through the principles of decolonization; identifying appropriate taxonomic units for conservation; improved quantification of the ecosystem services provided by mussels; and understanding how many mussels are enough to provide these services. Solutions for addressing the topics ranged from ecological studies to technological advances and socio-political engagement. Prioritization of our topics can help to drive a proactive approach to the conservation of this declining group which provides a multitude of important ecosystem services.This publication is based upon work from COST Action CA18239, supported by COST (European Cooperation in Science and Technology). DCA was supported by Corpus Christi College and a Dawson Fellowship at St. Catharine's College, Cambridge. MLL was supported by FCT-Fundacao para a Ciencia e a Tecnologia (2020.03608.CEECIND). ISO was supported by a Whitten Studentship. INB was supported by the Russian Science Foundation (grant no. 21-17-00126). YVB was supported by RSF project no. 21-14-00092. KD was supported by the Czech Science Foundation (19-05510 S). TZ was supported by statutory funds of IOP PAN. MK was supported by funding through the Australian National Environmental Science Program. For the purpose of open access, the author has applied a Creative Commons Attribution (CC BY) licence to any Author Accepted Manuscript version arising from this submission
The crown pearl: a draft genome assembly of the European freshwater pearl mussel Margaritifera margaritifera (Linnaeus, 1758)
Since historical times, the inherent human fascination with pearls turned the freshwater pearl mussel Margaritifera margaritifera (Linnaeus, 1758) into a highly valuable cultural and economic resource. Although pearl harvesting in M. margaritifera is nowadays residual, other human threats have aggravated the species conservation status, especially in Europe. This mussel presents a myriad of rare biological features, e.g. high longevity coupled with low senescence and Doubly Uniparental Inheritance of mitochondrial DNA, for which the underlying molecular mechanisms are poorly known. Here, the first draft genome assembly of M. margaritifera was produced using a combination of Illumina Paired-end and Mate-pair approaches. The genome assembly was 2.4 Gb long, possessing 105,185 scaffolds and a scaffold N50 length of 288,726 bp. The ab initio gene prediction allowed the identification of 35,119 protein-coding genes. This genome represents an essential resource for studying this species' unique biological and evolutionary features and ultimately will help to develop new tools to promote its conservation.A.G.-d.-S. was funded by the Portuguese Foundation for Science and
Technology (FCT) under the grants SFRH/BD/137935/2018, EF (CEECIND/00627/2017) and MLL (2020.03608.CEECIND). This research was developed
under ConBiomics: the missing approach for the Conservation of freshwater Bivalves Project No. NORTE-01-0145-FEDER- 030286, co-financed
by COMPETE 2020, Portugal 2020 and the European Union through
the ERDF, and by FCT through national funds. Additional strategic funding
was provided by FCT UIDB/04423/2020 and UIDP/04423/2020. Authors’ interaction
and writing of the article was promoted and facilitated by the COST
Action CA18239: CONFREMU—Conservation of freshwater mussels: a pan-
European approach.info:eu-repo/semantics/publishedVersio
Expansion and systematics redefinition of the most threatened freshwater mussel family, the Margaritiferidae.
Two Unionida (freshwater mussel) families are present in the Northern Hemisphere; the Margaritiferidae, representing the most threatened of unionid families, and the Unionidae, which include several genera of unresolved taxonomic placement. The recent reassignment of the poorly studied Lamprotula rochechouartii from the Unionidae to the Margaritiferidae motivated a new search for other potential species of margaritiferids from members of Gibbosula and Lamprotula. Based on molecular and morphological analyses conducted on newly collected specimens from Vietnam, we here assign Gibbosula crassa to the Margaritiferidae. Additionally, we reanalyzed all diagnostic characteristics of the Margaritiferidae and examined museum specimens of Lamprotula and Gibbosula. As a result, two additional species are also moved to the Margaritiferidae, i.e. Gibbosula confragosa and Gibbosula polysticta. We performed a robust five marker phylogeny with all available margaritiferid species and discuss the taxonomy within the family. The present phylogeny reveals the division of Margaritiferidae into four ancient clades with distinct morphological, biogeographical and ecological characteristics that justify the division of the Margaritiferidae into two subfamilies (Gibbosulinae and Margaritiferinae) and four genera (Gibbosula, Cumberlandia, Margaritifera, and Pseudunio). The systematics of the Margaritiferidae family is re-defined as well as their distribution, potential origin and main biogeographic patterns
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