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Artstale: Lakrød møgbille

Plants regulate soils and microclimate, provide substrate for heterotrophic taxa, are easy to observe and identify and have a stable taxonomy, which strongly justifies the use of plants as bioindicators in monitoring and conservation. However, insects and fungi make up the vast majority of species. Surprisingly, it remains untested whether plants are strong predictors of total multi-taxon species richness. To answer this question, we collected an extensive data set on species richness of vascular plants, bryophytes, macrofungi, lichens, plant-galling arthropods, gastropods, spiders, carabid beetles, hoverflies and OTU richness from environmental DNA metabarcoding. Plant species richness per se was a moderate predictor of richness of other taxa. Taking an ecospace approach to modelling, the addition of plant-derived bioindicators revealed 1) a consistently positive effect of plant richness on other taxa, 2) prediction of 12-55% of variation in other taxa and 48 % of variation in the total species richness.

1. Plants regulate soils and microclimate, provide substrate for heterotrophic taxa, are easy to observe and identify and have a stable taxonomy, which strongly justifies their use as indicators in monitoring and conservation. However, there is no consensus as to whether plants are strong predictors of total multi-taxon species richness. In this study we investigate if general terrestrial species richness can be predicted by vascular plant richness and bioindication. 2. To answer this question, we collected an extensive data set on species richness of vascular plants, bryophytes, macrofungi, lichens, plant-galling arthropods, gastropods, spiders, carabid beetles, hoverflies and genetic richness (Operational Taxonomic Units = OTUs) from environmental DNA metabarcoding. We also constructed a Conservation Index based on threatened red list species. Besides using richness of vascular plants for prediction of other taxonomic groups, we also used plant-derived calibration of the abiotic environment (moisture, soil fertility and light conditions) as well as the degree of anthropogenic impact. 3. Bivariate relationships between plant species richness and other species groups showed no consistent pattern. After taking environmental calibration by bioindication into account, we found a consistent, and for most groups significant, positive effect of plant richness. Plant species richness was also important for richness of fungal OTUs, Malaise OTUs and for the Conservation Index. Our multiple regression analyses revealed 1) a consistently positive effect of plant richness on other taxa, 2) prediction of 12-55% of variation in other taxa and 48% of variation in the total species richness when bioindication and plant richness were used as predictors. 4. Our results justify that vascular plants are strong indicators of total biodiversity across environmental gradients and broad taxonomic realms and therefore a natural first choice for biodiversity monitoring and conservation planning. Plants regulate soils and microclimate, provide substrate for heterotrophic taxa, are easy to observe and identify and have a stable taxonomy, which strongly justifies their use as indicators in monitoring and conservation. However, there is no consensus as to whether plants are strong predictors of total multi-taxon species richness. In this study, we investigate if general terrestrial species richness can be predicted by vascular plant richness and bioindication. To answer this question, we collected an extensive dataset on species richness of vascular plants, bryophytes, macrofungi, lichens, plant-galling arthropods, gastropods, spiders, carabid beetles, hoverflies, and genetic richness (operational taxonomic units = OTUs) from environmental DNA metabarcoding. We also constructed a Conservation Index based on threatened red list species. Besides using richness of vascular plants for prediction of other taxonomic groups, we also used plant-derived calibration of the abiotic environment (moisture, soil fertility and light conditions) as well as the degree of anthropogenic impact. Bivariate relationships between plant species richness and other species groups showed no consistent pattern. After taking environmental calibration by bioindication into account, we found a consistent, and for most groups significant, positive effect of plant richness. Plant species richness was also important for richness of fungal OTUs, Malaise OTUs and for the Conservation Index. Our multiple regression analyses revealed (a) a consistently positive effect of plant richness on other taxa, (b) prediction of 12%–55% of variation in other taxa and 48% of variation in the total species richness when bioindication and plant richness were used as predictors. Our results justify that vascular plants are strong indicators of total biodiversity across environmental gradients and broad taxonomic realms and therefore a natural first choice for biodiversity monitoring and conservation planning.

BackgroundIn light of the biodiversity crisis and our limited ability to explain variation in biodiversity, tools to quantify spatial and temporal variation in biodiversity and its underlying drivers are critically needed. Inspired by the recently published ecospace framework, we developed and tested a sampling design for environmental and biotic mapping. We selected 130 study sites (40 × 40 m) across Denmark using stratified random sampling along the major environmental gradients underlying biotic variation. Using standardized methods, we collected site species data on vascular plants, bryophytes, macrofungi, lichens, gastropods and arthropods. To evaluate sampling efficiency, we calculated regional coverage (relative to the known species number per taxonomic group), and site scale coverage (i.e., sample completeness per taxonomic group at each site). To extend taxonomic coverage to organisms that are difficult to sample by classical inventories (e.g., nematodes and non-fruiting fungi), we collected soil for metabarcoding. Finally, to assess site conditions, we mapped abiotic conditions, biotic resources and habitat continuity.ResultsDespite the 130 study sites only covering a minute fraction (0.0005 %) of the total Danish terrestrial area, we found 1774 species of macrofungi (54 % of the Danish fungal species pool), 663 vascular plant species (42 %), 254 bryophyte species (41 %) and 200 lichen species (19 %). For arthropods, we observed 330 spider species (58 %), 123 carabid beetle species (37 %) and 99 hoverfly species (33 %). Correlations among species richness for taxonomic groups were predominantly positive. Overall, sample coverage was remarkably high across taxonomic groups and sufficient to capture substantial spatial variation in biodiversity across Denmark. This inventory is nationally unprecedented in detail and resulted in the discovery of 143 species with no previous record for Denmark. Comparison between plant OTUs detected in soil DNA and observed plant species confirmed the usefulness of carefully curated environmental DNA-data. Species richness did not correlate well among taxa suggesting differential and complex biotic responses to environmental variation.ConclusionsWe successfully and adequately sampled a wide range of diverse taxa along key environmental gradients across Denmark using an approach that includes multi-taxon biodiversity assessment and ecospace mapping. Our approach is applicable to assessments of biodiversity in other regions and biomes where species are structured along environmental gradient.

The archetypical venomous lizard species are the helodermatids, the gila monsters (Heloderma suspectum) and the beaded lizards (Heloderma horridum). In the present study, the gila monster venom proteome was characterized using 2D-gel electrophoresis and tandem mass spectrometry-based de novo peptide sequencing followed by protein identification based on sequence homology. A total of 39 different proteins were identified out of the 58 selected spots that represent the major constituents of venom. Of these proteins, 19 have not previously been identified in helodermatid venom. The data showed that helodermatid venom is complex and that this complexity is caused by genetic isoforms and post-translational modifications including proteolytic processing. In addition, the venom proteome analysis revealed that the major constituents of the gila monster venom are kallikrein-like serine proteinases (EC 3.4.21) and phospholipase A2 (type III) enzymes (EC 3.1.1.4). A neuroendocrine convertase 1 homolog that most likely converts the proforms of the previously identified bioactive exendins into the mature and active forms was identified suggesting that these peptide toxins are secreted as proforms that are activated by proteolytic cleavage following secretion as opposed to being activated intracellularly. The presented global protein identification-analysis provides the first overview of the helodermatid venom composition. Biological significance: The helodermatid lizards are the classical venomous lizards, and the pharmacological potential of the venom from these species has been known for years; best illustrated by the identification of exendin-4, which is now used in the treatment of type 2 diabetes. Despite the potential, no global analyses of the protein components in the venom exist. A hindrance is the lack of a genome sequence because it prevents protein identification using a conventional approach where MS data are searched against predicted protein sequences based on the genome sequence. However, in the recent years the development of software tools for de novo sequencing and homology searches have improved significantly facilitating the first global analysis of the major protein components of helodermatid venom presented in this study. We have used a 2D-gel approach and determined the protein components in the 58 major spots resulting in the identification of 39 unique proteins. Of these, 19 have not previously been identified in helodermatid venom. The analysis provides results with impact on our understanding of the function and evolution of venom proteins, and serves as a basis for further unraveling of the pharmaceutical potential of the venom components.