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  • Open access
  • 48 Reads
Assessing the effect of climate change in vascular plants with disjunct populations

Many species exhibit intraspecific ecological variation and to not consider this ecological differentiation can confound predictions made with species distribution models (SDMs). This problem may be particularly relevant for species where there are few populations with potential local adaptations. To increase the performance of niche models and provide more solid basis for conservation plans, it is recommended to apply a subdivision criterion with biological significance. In this study, we examined twelve species with disjunct populations and created models of both the entire species and each group of populations. In addition, we considered as “aggregate model” for the species the area predicted to be suitable by at least one of each group of populations. In general, highest range contractions were identified by the species model. The species model forecasted a similar trend as the aggregate model in the majority of species, but in four cases they predicted opposite trends. In summary, our results suggest that the inclusion of intraspecific variability does not significantly improve the overall accuracy of SDMs based on all species occurrences but may lead to substantially different conclusions about future range changes. Furthermore, they suggest that intraspecific variability alone may provide a buffer against environmental change, even if the niche is conserved among different intraspecific groups. Consideration of intraspecific differences may ultimately allow us to highlight potential resilience units that can act as potential buffers against the adverse effects of climate change, and to develop targeted conservation strategies accordingly.

  • Open access
  • 43 Reads
Genetic diversity and population structure assessed by SSR in a Peruvian germplasm collection of loche squash (Cucurbita moschata, Cucurbitaceae)

Loche is an ancient landrace of squash from Northern Peru, notable for its vegetative reproduction and lack of seeds in fruits. Studies on this crop have been focused mainly on its nutritional properties and agronomic management. However, very little is known about its genetics. Here, we used 21 simple sequence repeats (SSRs) to assess the genetic diversity and population structure of a collection of 100 samples of loche from three localities in Peru, and 10 samples of related species, C. pepo and C. maxima (110 accessions in total). A total 85 bands were manually scored, obtaining an average of 4.05 alleles per locus. UPGMA clustering method was used to generate a dendrogram, and similar to the principal coordinate analysis (PCoA), it showed a clear identification between the three species of Cucurbita. Discriminant analysis of principal components (DAPC) clustered the 110 accessions into four populations: (i) two of loche, (ii) one of C. pepo, and (iii) one of C. maxima. Genetic diversity (i.e. expected heterozigosity) estimation was conducted considering only the two groups (populations) of loche identified by DAPC algorithm, which was 0.03 as an average. The standardized index of association was greater than zero demonstrating that loche is a clonal population. AMOVA revealed the greatest variation between populations (74.58%) and indicated that variability within populations is 25.42%. Vegetative propagation by means of stem cuttings and cultivation in a very restricted geographical area would explain the rather low diversity of loche. This in turn would suggest that the apparent variation observed in fruit shape may be explained by somatic mutation and/or environmental factors. Our next step is to employ NGS tools on this landrace to develop molecular tools that will promote its modern genetic improvement and sustainable management. However, further studies are needed for a more accurate evaluation of phenotypic traits of this precious crop.

  • Open access
  • 59 Reads
Diversity patterns of benthic assemblages on intertidal estuarine seagrass beds in Aveiro (Portugal)

Seagrass meadows are very productive ecosystems and many animal species are dependent of these meadows, including a wide diversity of invertebrates. This study aims to explore spatial diversity patterns of benthic invertebrates associated to Zostera noltei Hornemann, 1832 meadows. Three meadows (A, B, C) were sampled along the salinity gradient of Ria de Aveiro. At each meadow two sites were selected and four core were taken at each site. Fauna was sorted, counted and identified to the lowest taxonomical level. ANOVA tests showed significant differences of taxa number and abundance among meadows. Highest values of species and individuals were found in meadow A (31 taxa and 3342 individuals). Lowest values of individuals were found in B (970) and lowest values of taxa in B and C (20). PERMANOVA allowed to identify significant differences among meadows, being the meadow B similar to C and both distinct from A. Simper analyses showed the main taxa responsible of the differences. These taxa included annelids (Oligochaetes, Hediste diversicolor (O.F. Müller, 1776) and Notomastus latericeus Sars, 1851), molluscs (Peringia ulvae (Pennant, 1777) and Scrobicularia plana (da Costa, 1778)), crustaceans (Cyathura carinata (Krøyer, 1847)) and nematodes. It was also observed that some annelids as N. latericeus and oligochaete and the gastropod P. ulvae presented density gradient of abundance along the lagoon from the inner side to the outer.

Acknowledgements: This research was developed under Project No. 029818, co-financed by COMPETE 2020, Portugal 2020 and the European Union through the ERDF, and by FCT through national funds.

  • Open access
  • 48 Reads
Agroecosystems and plant diversity: Olive groves understorey, under different management practices in Greece

Agroecosystems often dominate in Mediterranean area and their management strongly affects biodiversity. In Greece, about one third of the olive groves are organic – with environment friendly farming practices - while the rest includes conventional or abandoned olive groves. The current study aims to investigate plant species diversity of olive groves under different management practices. Authors unpublished data from field surveys on different insular and mainland areas have been used, together with already published data. The results showed that organic olive groves are characterized by a rich and diverse flora, mainly dominated by therophytes and especially of annual leguminous species and other insect-pollinated plants that are indicators of long-term but moderate human interference. Conventional olive groves have a poor and rather common flora also dominated by therophytes. Abandoned olive groves present a rather poor but diverse flora, mainly dominated by hemicryptophytes and phanerophytes and to a lower proportion of annual plants, depending also on when they have been abandoned.

  • Open access
  • 42 Reads
Defensive secretions of Amazonian opilionids from Republic of Ecuador
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About 120 species of opilionids have been described in Ecuador (7000 worldwide), The Ecuadorian Amazon is the region where the greatest number of species is concentrated. opilionids inhabit humid and shaded habitats and are generally nocturnal. these species possess glands secreting defensive secretions containing benzoquinonoids (benzoquinones and polysubstituted phenols). in this study we report the defensive compositions of neotropical opilionids inhabiting the Arajuno region, Ecuador, at the Jura Jura Kawsay Scientific Station of the Central University of Ecuador. The GC examination of the extract obtained from the defensive secretion of these Gonyleptidae (Order Laniatores, Opilinida) revealed the presence of five volatile components, three benzoquinones and two hydroquinones, being the major component 2,3-dimethyl-1,4-benzoquinone. A wide variety of benzoquinonoids have been characterized from plant and microbial sources, as well as from marine organisms.Among terrestrial invertebrates, benzoquinonoids are widely biosynthesized by arthropods including, besides millipedes, insects and opilionids. There seems little doubt that in theses invertebrates the benzoquinonoids secretions serve to repel predators and pathogenic microorganisms.

  • Open access
  • 78 Reads
Characterization of the trophic niche for a Rockfish community in southeast Alaska
, ,

Rockfish are a group of marine fishes that exhibit significant ecological diversity as well as demand economic importance due to commercial and recreational fishing. We sampled Rockfish tissue from 2013 to 2018 in southeast Alaska off the southeast coast of Admiralty Island. Our objective was to characterize trophic niche and position of the Rockfish community using stable isotope analysis. We also wanted to observe any potential patterns regarding hypotheses of community composition. We found that the Rockfish community occupied a unique position in isospace in the context of other common species. Further, the isotopic niches of each Rockfish species were smaller than other common species. Between Rockfish communities, pelagic Rockfish occupied a significantly larger portion of isopace than demersal rockfish. The small niche size of Rockfish species compared to the large niche size of cooccurring common species suggests that the Rockfish community follows a niche differentiation model rather than a lottery model of community composition. The small niche size in isospace may be a function of competitive pressures among Rockfish species. Additionally, this pressure may be more prevalent in demersal Rockfish communities because they had generally smaller niche sizes than pelagic Rockfish.

  • Open access
  • 69 Reads
Exploring lampenflora of Resavska Cave, Serbia

Lampenflora, a complex phototrophic community developing near artificial light in show caves, is recognized as a major concern for cave management and its regular monitoring became necessity. For the purpose of this work, monitoring was done in one of the most visited show caves in Serbia – Resavska Cave, directly before and after the main season in 2021, in March and November. Lampenflora was localized and developed mainly near artificial light, further parts of the cave were not affected. Different sampling sites (twelve in total) regarding type of artificial light and type of biofilm were chosen for lampenflora sampling. Two biofilm types were recognized in situ: epilithic/endolithic ones dominated by algae and/or Cyanobacteria and moss dominated biofilms. Analysis of phototrophic microorganisms revealed the presence of Cyanobacteria, Chlorophyta and Bacillariophyta. The highest diversity was found in Cyanobacteria where genera Aphanocapsa, Eucapsis, Gloeocapsa and Leptolyngbya were recorded during both samplings, Nostoc and Synechocystis in March, Hassalia, Oscillatoria and Pseudocapsa only in November. Chlorophyta were represented with Chlorella, Desmococcus, Klebsormidium, Mesotaenium, Stichococcus in March and the same taxa except Klebsormidium in November. Humidophila was the most widespread diatom in fresh biofilm samples. Aside from higher diversity, Cyanobacteria were sporadically found in samples except on two sampling sites where Aphanocapsa cf. muscicola and Hassalia sp. were abundant. Chlorophyta dominated in samples, which is in accordance with many other studies. Ecological parameters – temperature, relative air humidity, light intensity, substratum moisture and substratum pH were also determined and related to degree of colonization and community composition.

  • Open access
  • 57 Reads
Conservation Status of Globally Testudines River Terrapins Based on DNA Barcoding

River terrapins are turtle types that live in freshwater or brackish water. There are 12 species of river terrapin worldwide. A total of 26 COI sequences of worldwide river terrapins were used in this study. The study aims to determine the global utility of river terrapin DNA barcoding using novel COI sequences and compare them to other COI sequences previously published in BOLD systems and GenBank. Nevertheless, the conservation status of the river terrapins is also taken into account for sustainability priority. The sequences contained three families, as determined by the UPGMA tree, with 33% of river terrapins classified as least concern (LC) and 25% classified as critically endangered (CR). The genomic and bioinformatics analyses of river terrapins reported here may serve as a foundation for future research on this species throughout the world.

  • Open access
  • 63 Reads
Genetic diversity of Barbary macaques (Macaca sylvanus) and its implications in conservation management of the species

Barbary macaques (Macaca sylvanus) are critically endangered primates. They are
unique within their genus, as the only African macaque. By the late Miocene, their habitat
extended across Northern Africa and in Southern Europe. Aside from an introduced population
in Gibraltar, their current distribution is reduced to disjointed forests in Algeria and Morocco.
Our knowledge of the phylogeographic history and intra-specific diversity of this highly
endangered species is also fragmented. In this study we aimed to improve our understanding
of the phylogeographic history and genetic diversity of the Barbary macaque by expanding the
genetic data available on the Algerian populations. Moreover, we investigated captive
populations of Barbary macaques for comparison to wild populations. The mtDNA
hypervariable control region I was sequenced using DNA extracts from faecal and hair samples
from wild and captive populations. The newly produced data (N = 157), from both Algerian
and Moroccan populations, were combined with previously published data (N = 212) and used
to characterize genetic variability and reconstruct phylogenetic relationships among wild and
captive populations. We found that Algerian populations exhibit an increased genetic diversity
relative to Moroccan populations. Phylogenetic relationships suggest that the Moroccan
populations diversified after being isolated from the Algerian populations. Captive populations
were found to be not fully representative of the genetic diversity exhibited in the species, but
rather only of Moroccan populations. Findings in this study suggest that the fragmented
Algerian populations should be managed to increase gene flow between them by increasing
habitat connectivity where it is feasible.

  • Open access
  • 19 Reads
Effect of land-use change over arbuscular mycorrhizal fungi diversity in an Argentinian endemic native forest

Arbuscular mycorrhizal fungi (AMF, Glomeromycota) are biotrophic mutualistic symbionts of 80% of the terrestrial plants. AMF increase their hosts’ growth through its contribution to the water and nutrients absorption from soil to the plant roots. The different AMF taxa vary in their edaphic and nutritional preferences, the host species ranges and the seasonal changes in sporulation features. The increase in world human population and the global demand for natural resources have acted as an important driving force for agricultural changes in Argentina in the last 150 years. Particularly, the Prosopis caldenia Burkart forests (or "Caldenales") have suffered an important reduction in the last 10 years. Here, we studied AMF abundance and diversity in four land uses and their relationship with soil and vegetation characteristics. The land use selected were Native Forest (Caldenales), Eragrostis curvula (Schrad.) Nees pasture, Medicago sativa L. cropfield and soybean (Glicine max (L.) Merill) cropfield. AMF spores were extracted from soil by the traditional method and were identified by morphological features. Cluster analysis divided the land uses into two groups, Kruskal-Wallis show significant differences in AMF abundance and richness between land uses, AMF abundance and tree richness were negatively correlated, showing less abundance of AMF spores in the plots with the highest richness of tree species, and ANOSIM analysis show differences between land uses. Our results suggested that land use and vegetation richness have a strong influence on the AMF community. Agricultural activities would negatively influence AMF species diversity but would not affect negatively spores abundance.

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