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Povzetek: Cystoseira s.l. forests are recognised as important habitats which host diverse coastal fish assemblages. Many fish species use such habitats as feeding, breeding, and nursery grounds. Since the coastal fish community depends on the availability of dense macroalgal belts, the decline of these habitats in the Mediterranean Sea also affects the density of coastal fish species. We studied the coastal fish assemblage in Cystoseira s.l. forests in three consecutive years 2019–2021 in the Gulf of Trieste (Adriatic Sea). Data on coastal fish fauna were collected by visual counts conducted by SCUBA diving. Data on algal cover and habitat types were obtained by recording with a video camera. Similarities and differences in the fish community were analysed in terms of habitat and substrate preferences. A total of 34 species were recorded in Cystoseira forests. The results of the present study show that the different algal cover and associated depth gradient have different effects on the fish assemblage in coastal waters, affecting species composition and abundance. For many species, particularly labrids and sea breams, there is a decreasing temporal trend in frequency of occurrence and density. However, fish community trends can be used as a good “proxy” to evaluate the algal belt status. Our results indicate that rapid conservation and restoration actions are needed to stem the decline of Cystoseira s.l. forests.
Ključne besede: Cystoseira s.l. forests, fish assemblage, fish biodiversity, habitat preference, macroalgal belt, Mediterranean Sea
Objavljeno v DiRROS: 12.07.2024; Ogledov: 94; Prenosov: 97
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Ključne besede: biodiversity, remote sensing, oceanography
Objavljeno v DiRROS: 09.07.2024; Ogledov: 127; Prenosov: 64
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Povzetek: Madagascar is a global biodiversity hotspot, but its biodiversity continues to be underestimated and understudied. Of raft spiders, genus Dolomedes Latreille, 1804, literature only reports two species on Madagascar. Our single expedition to humid forests of eastern and northern Madagascar, however, yielded a series of Dolomedes exemplars representing both sexes of five morphospecies. To avoid only using morphological diagnostics, we devised and tested an integrative taxonomic model for Dolomedes based on the unified species concept. The model first determines morphospecies within a morphometrics framework, then tests their validity via species delimitation using COI. It then incorporates habitat preferences, geological barriers, and dispersal related traits to form hypotheses about gene flow limitations. Our results reveal four new Dolomedes species that we describe from both sexes as Dolomedes gregoric sp. nov., D. bedjanic sp. nov., D. hydatostella sp. nov., and D. rotundus sp. nov. The range of D. kalanoro Silva & Griswold, 2013, now also known from both sexes, is expanded to eastern Madagascar. By increasing the known raft spider diversity from one valid species to five, our results merely scratch the surface of the true Dolomedes species diversity on Madagascar. Our integrative taxonomic model provides the framework for future revisions of raft spiders anywhere.
Ključne besede: raft spiders, integrative taxonomic model, Madagascar, biodiversity, integrative taxonomy, zoology
Objavljeno v DiRROS: 16.05.2024; Ogledov: 272; Prenosov: 384
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Povzetek: The ecological impacts of long-term (press) disturbance on mechanisms regulating the relative abundance (i.e., commonness or rarity) and temporal dynamics of species within a community remain largely unknown. This is particularly true for the functionally important arbuscular mycorrhizal (AM) fungi; obligate plant-root endosymbionts that colonize more than two-thirds of terrestrial plant species. Here, we use high-resolution amplicon sequencing to examine how AM fungal communities in a specific extreme ecosystem—mofettes or natural CO2 springs caused by geological CO2 exhalations—are affected by long-term stress. We found that in mofettes, specific and temporally stable communities form as a subset of the local metacommunity. These communities are less diverse and dominated by adapted, “stress tolerant” taxa. Those taxa are rare in control locations and more benign environments worldwide, but show a stable temporal pattern in the extreme sites, consistently dominating the communities in grassland mofettes. This pattern of lower diversity and high dominance of specific taxa has been confirmed as relatively stable over several sampling years and is independently observed across multiple geographic locations (mofettes in different countries). This study implies that the response of soil microbial community composition to long-term stress is relatively predictable, which can also reflect the community response to other anthropogenic stressors (e.g., heavy metal pollution or land use change). Moreover, as AM fungi are functionally differentiated, with different taxa providing different benefits to host plants, changes in community structure in response to long-term environmental change have the potential to impact terrestrial plant communities and their productivity
Ključne besede: arbuscular mycorrhiza, elevated CO2, long-term experiments, soil biodiversity, soil hypoxia, next-generation sequencing, NGS
Objavljeno v DiRROS: 28.02.2024; Ogledov: 380; Prenosov: 196
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Povzetek: The availability of public genomic resources can greatly assist biodiversity assessment, conservation, and restoration efforts by providing evidence for scientifically informed management decisions. Here we survey the main approaches and applications in biodiversity and conservation genomics, considering practical factors, such as cost, time, prerequisite skills, and current shortcomings of applications. Most approaches perform best in combination with reference genomes from the target species or closely related species. We review case studies to illustrate how reference genomes can facilitate biodiversity research and conservation across the tree of life. We conclude that the time is ripe to view reference genomes as fundamental resources and to integrate their use as a best practice in conservation genomics.
Ključne besede: genomics, biodiversity conservation
Objavljeno v DiRROS: 22.02.2023; Ogledov: 563; Prenosov: 395
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