Context
There is an urgent need to stop the biodiversity loss in European agricultural landscapes. These landscapes, due to their fragmentation, include a lot of edges, many of them between habitats ...of different quality in terms of biodiversity.
Objectives
Here, we ask how plant species richness is distributed from the interior of protected semi-natural grassland into the interior of adjacent crop fields, and which species groups determine the observed patterns.
Methods
At grassland–crop field interfaces in two German landscapes, we sampled the vegetation along transects extending 32 m into both habitats. Based on theory, we fitted different models to visualize the species richness curve along transects and selected the best model via AIC.
Results
The best fitting model for all species was monotone over the interface with a minimum in the field and a maximum in the grassland. This shape was driven by the generalists, showing the same pattern, while grassland specialists showed a sigmoid curve with an increase only in the grassland. Arable specialists had a peak at the field edge and decreased towards the grassland. Curves for Ellenberg indicator values for moisture, nutrients and light showed the same shape as the overall species curve, yet with an inverse pattern for light.
Conclusions
This is the first study revealing gradual responses of plant species richness at the grassland–crop field interface with a high spatial resolution. As these adjacent habitats influence each other far into their neighbourhood, attention should be given when conserving biodiversity in agricultural landscapes, particularly in case of often small and scattered protected areas.
Insects are the most diverse group of animals on Earth, but their small size and high diversity have always made them challenging to study. Recent technological advances have the potential to ...revolutionise insect ecology and monitoring. We describe the state of the art of four technologies (computer vision, acoustic monitoring, radar, and molecular methods), and assess their advantages, current limitations, and future potential. We discuss how these technologies can adhere to modern standards of data curation and transparency, their implications for citizen science, and their potential for integration among different monitoring programmes and technologies. We argue that they provide unprecedented possibilities for insect ecology and monitoring, but it will be important to foster international standards via collaboration.
Rapid changes of the biosphere observed in recent years are caused by both small and large scale drivers, like shifts in temperature, transformations in land-use, or changes in the energy budget of ...systems. While the latter processes are easily quantifiable, documentation of the loss of biodiversity and community structure is more difficult. Changes in organismal abundance and diversity are barely documented. Censuses of species are usually fragmentary and inferred by often spatially, temporally and ecologically unsatisfactory simple species lists for individual study sites. Thus, detrimental global processes and their drivers often remain unrevealed. A major impediment to monitoring species diversity is the lack of human taxonomic expertise that is implicitly required for large-scale and fine-grained assessments. Another is the large amount of personnel and associated costs needed to cover large scales, or the inaccessibility of remote but nonetheless affected areas.
To overcome these limitations we propose a network of Automated Multisensor stations for Monitoring of species Diversity (AMMODs) to pave the way for a new generation of biodiversity assessment centers. This network combines cutting-edge technologies with biodiversity informatics and expert systems that conserve expert knowledge. Each AMMOD station combines autonomous samplers for insects, pollen and spores, audio recorders for vocalizing animals, sensors for volatile organic compounds emitted by plants (pVOCs) and camera traps for mammals and small invertebrates. AMMODs are largely self-containing and have the ability to pre-process data (e.g. for noise filtering) prior to transmission to receiver stations for storage, integration and analyses. Installation on sites that are difficult to access require a sophisticated and challenging system design with optimum balance between power requirements, bandwidth for data transmission, required service, and operation under all environmental conditions for years. An important prerequisite for automated species identification are databases of DNA barcodes, animal sounds, for pVOCs, and images used as training data for automated species identification. AMMOD stations thus become a key component to advance the field of biodiversity monitoring for research and policy by delivering biodiversity data at an unprecedented spatial and temporal resolution.
Recent advances in molecular phylogenetics and a series of important palaeobotanical discoveries have revolutionized our understanding of angiosperm diversification. Yet, the origin and early ...evolution of their most characteristic feature, the flower, remains poorly understood. In particular, the structure of the ancestral flower of all living angiosperms is still uncertain. Here we report model-based reconstructions for ancestral flowers at the deepest nodes in the phylogeny of angiosperms, using the largest data set of floral traits ever assembled. We reconstruct the ancestral angiosperm flower as bisexual and radially symmetric, with more than two whorls of three separate perianth organs each (undifferentiated tepals), more than two whorls of three separate stamens each, and more than five spirally arranged separate carpels. Although uncertainty remains for some of the characters, our reconstruction allows us to propose a new plausible scenario for the early diversification of flowers, leading to new testable hypotheses for future research on angiosperms.
At the current rates of species extinction on a global level, Red List assessments need to speed up to inform conservation management in a timely manner. This study analyzed the progress made over ...the last 10 years in red listing aquatic invertebrates in Northern Europe. A survey of 43 freshwater molluscs and 1492 marine crustaceans was carried out for their Red List status in twelve countries during a twenty year interval (2003−2022). Our survey demonstrated that many countries have no national Red List or outdated Red Lists for the freshwater molluscs and only four countries have assessed their existing crustacean species. Alarmingly, we find 13 % fewer occurrence records for the crustaceans and 48 % fewer records for the freshwater molluscs in GBIF in the last 10 years (2013−2022) than in the 10 years previously (2003−2012). A barcode gap analysis reveals more barcodes for the 16S gene (77 %) than for the COI gene (63 %) for the freshwater molluscs and even fewer barcodes for the marine crustaceans (17 % for 16S and 40 % for the COI gene). With the current methods, regular comprehensive red listing of aquatic invertebrates is unrealistic. Here we present a set of scripts that allow automated occurrence and barcode gap analyses on unrepresented species groups. Finally, we discuss ways to increase the number of occurrence records and speed up red listing under existing European frameworks through whole community screening of ecosystems using molecular and other emerging tools.
•Red listing for aquatic invertebrates needs to speed up to inform conservation.•A North European survey of molluscs and crustaceans was carried for the last 20 years.•Red lists for the aquatic invertebrates are either lacking or not up to date. · Regular and comprehensive red listing of aquatic invertebrates is unrealistic.•Citizen science and eDNA community screening can increase the number of occurrences.
The occurrence and distribution of insects and their possible associations with plant species are largely unknown in Germany and baseline data to monitor future trends are urgently needed. Using ...newly-designed automated Malaise trap multi-samplers, the occurrence of insect species and their potential associations with plants was monitored synchronously at two contrasting field sites in Germany: an urban botanical garden and a forest research station. Taxa were identified by metabarcoding of the insects and the plant traces present in the preservative ethanol of the Malaise trap samples. For comparison, a botanical survey was conducted in the vicinity of the traps. Across both sites, we identified a total of 1290 exact sequence variants (ESVs) assigned to Insecta, of which 205 are known to be pollinators. In the botanical garden, we detected the occurrence of 128 plant taxa, of which 41 also had one of their known insect pollinator species detected. Insect species richness was highest in May, mainly attributed to an increase in Diptera. These results present a case study of the applicability of automated sampling and DNA-based methods to monitor the timings of flowering and corresponding activity of plant-visiting insects.
Foliage and reproductive structures of Platanaceae from the Upper Cretaceous (Santonian) of Quedlinburg, Central Germany, were comparatively studied and their systematic affinities established. One ...type of foliage preserved in sandstone and rarely in clayish siltstone belongs to the extinct genus
Credneria. The leaves are typically obovate with a pinnate-actinodromous venation and distinct suprabasal veins. In addition, a substantial number of leaves preserved in siltstone and rarely in sandstone are identical to modern
Platanus based on leaf architecture and epidermal features. As in modern
Platanus leaf margin and size were found to be of no systematic significance in both fossil leaf types. Further, staminate flower heads preserved as cleavage compressions in siltstone were found in association with
Platanus leaves; they contain pollen that is identical to modern
Platanus in size and type of tectum. In addition, a few three-dimensionally preserved staminate flower heads with ca. 50 flowers on a receptaculum are described. Each flower appears to have a two-whorled perianth and six or seven stamens. The organs of the outer perianth whorl show a distinct epidermal cell pattern different from the inner ones. All perianth organs have the same length as the stamens. Stamens are bithecate and contain pollen identical to that found in compression fossils. Pistillate heads preserved in siltstone consist of numerous achenes with persistent styles, which show close similarity to modern
Platanus. It remains unclear, whether additional inflorescence heads of uncertain sex found in sandstone that are slightly larger than those preserved in siltstone belong to the leaves of
Credneria. Association evidence links vegetative and reproductive structures preserved in siltstone and indicates the presence of the modern genus
Platanus in the Santonian.
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