Browsing by Subject "Insects"

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  • Andersen, Line Holm; Nummi, Petri; Rafn, Jeppe; Frederiksen, Cecilie Majgaard Skak; Kristjansen, Mads Prengel; Lauridsen, Torben Linding; Trojelsgaard, Kristian; Pertoldi, Cino; Bruhn, Dan; Bahrndorff, Simon (2021)
    The succession-driven reed bed habitat hosts a unique flora and fauna including several endangered invertebrate species. Reed beds can be managed through commercial winter harvest, with implications for reed bed conservation. However, the effects of winter harvest on the invertebrate community are not well understood and vary across studies and taxonomic levels. The aim of this study was to investigate the effects of reed harvest on invertebrate communities. Ground-dwelling and aerial invertebrates were continuously sampled for 10 weeks in the largest coherent reed bed of Scandinavia in order to assess how time since last reed harvest (0, 3, and 25years) influences invertebrate biomass, biodiversity and community structure across taxonomic levels. Biomass was measured and all specimens were sorted to order level, and Coleoptera was even sorted to species level. The invertebrate community showed distinct compositional differences across the three reed bed ages. Furthermore, biomass of both aerial and ground-dwelling invertebrates was highest in the age-0 reed bed and lowest in the age-25 reed bed. Generally, biodiversity showed an opposite trend with the highest richness and diversity in the age-25 reed bed. We conclude that it is possible to ensure high insect biomass and diversity by creating a mosaic of reed bed of different ages through small-scale harvest in the largest coherent reed bed in Scandinavia. The youngest red beds support a high invertebrate biomass whereas the oldest reed beds support a high biodiversity. Collectively, this elevate our understanding of reed harvest and the effects it has on the invertebrate communities, and might aid in future reed bed management and restoration.
  • Ariza, Gloria Maria; Jacome, Jorge; Kotze, D. Johan (2021)
    The tropical dry forest (TDF) ecosystem is characterised by strong seasonality exasperated periodically by the El Nino/southern oscillation (ENSO). The environment produced by this event could constrain the survival of small organisms, such as insects. Carabid beetles were collected in a TDF in Armero, Colombia, during wet and dry seasons in both El Nino and non-El Nino periods. A series of traits linked to desiccation resistance were measured to characterise their adaptation to the TDF environment and to investigate changes experienced by carabid beetles during both episodes in quantitative (assemblage) and qualitative (traits) parameters. We found no difference in the presence of traits between El Nino and non-El Nino episodes, but carabid assemblages changed significantly in composition and assemblage structure between these episodes. During both periods, small-sized and nocturnal species dominated the assemblages, but in terms of number of individuals, medium and large-sized, and visual hunter species dominated. Calosoma alternans and Megacephala affinis were the most abundant species with high dispersal capacity. Carabid beetles exhibited morphological traits well-adapted to drought experienced in TDF, including when it is exasperated by ENSO. However, long-term studies can help to elucidate the real effects of ENSO and to confirm the adaptation of carabid beetles to cope with this extreme environment.
  • Milicic, Marija; Vujic, Ante; Cardoso, Pedro (2018)
    Climate change presents a serious threat to global biodiversity. Loss of pollinators in particular has major implications, with extirpation of these species potentially leading to severe losses in agriculture and, thus, economic losses. In this study, we forecast the effects of climate change on the distribution of hoverflies in Southeast Europe using species distribution modelling and climate change scenarios for two time-periods. For 2041-2060, 19 analysed species were predicted to increase their areas of occupancy, with the other 25 losing some of their ranges. For 2061-2080, 55% of species were predicted to increase their area of occupancy, while 45% were predicted to experience range decline. In general, range size changes for most species were below 20%, indicating a relatively high resilience of hoverflies to climate change when only environmental variables are considered. Additionally, range-restricted species are not predicted to lose more area proportionally to widespread species. Based on our results, two distributional trends can be established: the predicted gain of species in alpine regions, and future loss of species from lowland areas. Considering that the loss of pollinators from present lowland agricultural areas is predicted and that habitat degradation presents a threat to possible range expansion of hoverflies in the future, developing conservation management strategy for the preservation of these species is crucial. This study represents an important step towards the assessment of the effects of climate changes on hoverflies and can be a valuable asset in creating future conservation plan, thus helping in mitigating potential consequences.
  • Mochulskii, Viktor Ivanovich, ca. 1810-1871. (Helsingfors, Imprimerie de la Société de Litérature Finnoise, 1856)
  • Vauterin, Aleksis (Helsingin yliopisto, 2020)
    Many European citizens have growing concerns over climate change. This seems to go together with the debate about the impact of consumers’ personal dietary choices on climate change. Novel food protein sources are entering the European food market to replace or compensate meat protein sources. One protein food alternative are insect-based proteins. However, there is limited research as to how choices of alternative insect-based protein products may influence consumers’ carbon footprints. This study explores the potential of insect protein to reduce the carbon footprint associated with European food consumption. Three scenarios were formed to identify and describe options for reducing current levels of carbon footprints associated with the consumption of conventionally produced chicken meat. In the scenarios, soybean meal-based feeds used in conventional chicken production are replaced with insect-based feeds, and chicken products are replaced with protein food products from insects. Further, two different insect feeding sources are considered and compared to each other. A number of existing global warming potential values from a variety of Life Cycle Assessment studies focusing on chicken and insect production were collected to create a database for use in the scenario analyses. The database was utilised to assess the global warming impact of producing alternative insect protein on the carbon footprint of European food consumption. The results from the three scenarios indicate that the carbon footprint of food consumption can be reduced by replacing conventionally produced chicken meat with insect-based protein food products. However, insect-based protein products would have a positive impact on the carbon footprint only if the insects that are produced for use in feed or food are farmed with low-value side streams. Currently, the shift to an increased use of side streams in insect-based food production faces regulatory challenges in Europe. In the light of European efforts to encourage sustainable food alternatives, and considering the environmental benefits insects could offer as alternative proteins over options of conventional protein sources, there is a need for continued research on the environmental sustainability of insect eating and insect feeding, as well as the safety and regulatory issues related to the use of insect protein in food consumption.
  • Popov, S.; Milicic, M.; Diti, I.; Marko, O.; Sommaggio, D.; Markov, Z.; Vujic, A. (2017)
    Spatial and temporal differences in landscape patterns are of considerable interest for understanding ecological processes. In this study, we assessed habitat quality by using the Syrph The Net database and data on decreasing species richness over a 25-year period for the two largest phytophagous hoverfly genera (Merodon and Cheilosia). Furthermore, within this time frame, we explored congruence between ecological responses (species richness and Biodiversity Maintenance Function for these two genera) and landscape structural changes through correlation analysis. Our results indicate that landscapes have experienced changes in aggregation, isolation/connectivity and landscape diversity, with these parameters being significantly correlated with Cheilosia species richness loss and habitat quality. We conclude that the genus Cheilosia is a good bioindicator that can highlight not only the current quality of an area but also temporal changes in landscape patterns.
  • Muona, Jyrki; Chang, Huali; Ren, Dong (2020)
    Abstract: Recent molecular studies have suggested that the clicking beetle families Elateridae, Eucnemidae, Throscidae, and Cerophytidae evolved in the Jurassic and diversified in the Cretaceous. These studies paid little attention to fossils, using them only as dating tools. The identification of Elateridae fossils is challenging, as external synapomorphies are not known for this family. Elateridae can be identified only as something not belonging to the other related families, all of which have diagnostic synapomorphies. Most subfamilies and tribes of Elateridae do possess definite diagnostic characters, however, making their identification feasible. We checked the 28 Elateridae described from Chinese Mesozoic deposits. Twelve were Elateridae, seven were Eucnemidae, and one was a Throscidae. Three species could be Eucnemidae, but showed aberrant characters. Five species could not be placed and may not belong to Elateroidea at all. On the basis of these results we suggest that all previously described Elateridae fossils should be re-checked. They should be searched for synapomorphies defining Eucnemidae, Throscidae, and Cerophytidae. If such characters are not present, a click beetle type of fossil can be placed in Elateroidae incertae sedis. The Mesozoic Chinese Elateridae fossils all belong to clades that do not exist today, whereas the Mesozoic Eucnemidae subfamilies are extant ones. This may be the source of the disagreement between Elateridae fossil age and datings based on molecular studies. One new combination was made: Desmatus ponomarenkoi (Chang, Kiretjshuk & Ren, 2009) NEW COMBINATION (= Paradesmatus ponomarenkoi Chang, Kirejtshuk & Ren, 2009).