Browsing by Subject "insects"

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  • Lähteenmäki-Uutela, Anu; Rahikainen, Moona; Lonkila, Annika; Yang, Baoru (Butterworth Scientific, 2021)
    Food Control 130: 108336
    We ask how European food law impacts the transformative potential of alternative proteins, including single-cell proteins, plant-based novel proteins, cultured meat,macroalgae, and insects. The Novel Food Regulation may prove insurmountable for small companies, and it is demanding and time-consuming even for larger companies,dampening the transformative potential of all novel foods and traditional foods from third countries. Several microalgae and macroalgae are non-novel in the EU, which eases their way into the markets. The unclear novel food status of some potential green macroalgae species is a hindrance. All insects are novel, and none has EU-level authorization yet, although some Member States allow insect food. The GM Food Regulation is procedurally and scientifically demanding, and it forces GM labelling. The Regulation dampens the transformative potential of food GM technology. In addition to crops and fruit, GM Food Regulation applies to genetically modified or edited microbes,microalgae, cultured meat, and insects. The naming and labelling rules of plant-based products have caused controversy. From the business perspective, the health claims process is similarly challenging as the novel food process. EU food law must guarantee food safety and consumer rights while applying the principles of nondiscrimination and proportionality.
  • Milicic, Marija; Popov, Snezana; Vujic, Ante; Ivosevic, Bojana; Cardoso, Pedro (2020)
    1. Dark diversity represents the set of species that can potentially inhabit a given area under particular ecological conditions, but are currently 'missing' from a site. This concept allows characterisation of the mechanisms determining why species are sometimes absent from an area that seems ecologically suitable for them. 2. The aim of this study was to determine the dark diversity of hoverflies in south-eastern Europe and to discuss the role of different functional traits that might increase the likelihood of species contributing to dark diversity. Based on expert opinion, the Syrph the Net database and known occurrences of species, the study estimated species pools, and observed and dark diversities within each of 11 defined vegetation types for 564 hoverfly species registered in south-eastern Europe. To detect the most important functional traits contributing to species being in dark diversity across different vegetation types, a random forest algorithm and respective statistics for variable importance were used. 3. The highest dark diversity was found for southwest Balkan sub-Mediterranean mixed oak forest type, whereas the lowest was in Mediterranean mixed forest type. Three larval feeding modes (saproxylic, and phytophagous on bulbs or roots) were found to be most important for determining the probability of a species contributing to hoverfly dark diversity, based on univariate correlations and random forest analysis. 4. This study shows that studying dark diversity might provide important insights into what drives community assembly in south-eastern European hoverflies, especially its missing components, and contributes to more precise conservation prioritisation of both hoverfly species and their habitats.
  • de Jong, M. A.; Saastamoinen, Marjo (2018)
    Thermal tolerance has a major effect on individual fitness and species distributions and can be determined by genetic variation and phenotypic plasticity. We investigate the effects of developmental and adult thermal conditions on cold tolerance, measured as chill coma recovery (CCR) time, during the early and late adult stage in the Glanville fritillary butterfly. We also investigate the genetic basis of cold tolerance by associating CCR variation with polymorphisms in candidate genes that have a known role in insect physiology. Our results demonstrate that a cooler developmental temperature leads to reduced cold tolerance in the early adult stage, whereas cooler conditions during the adult stage lead to increased cold tolerance. This suggests that adult acclimation, but not developmental plasticity, of adult cold tolerance is adaptive. This could be explained by the ecological conditions the Glanville fritillary experiences in the field, where temperature during early summer, but not spring, is predictive of thermal conditions during the butterfly's flight season. In addition, an amino acid polymorphism (Ala-Glu) in the gene flightin, which has a known function in insect flight and locomotion, was associated with CCR. These amino acids have distinct biochemical properties and may thus affect protein function and/or structure. To our knowledge, our study is the first to link genetic variation in flightin to cold tolerance, or thermal adaptation in general.
  • Marquina, Daniel; Esparza-Salas, Rodrigo; Roslin, Tomas; Ronquist, Fredrik (2019)
    DNA metabarcoding allows the analysis of insect communities faster and more efficiently than ever before. However, metabarcoding can be conducted through several approaches, and the consistency of results across methods has rarely been studied. We compare the results obtained by DNA metabarcoding of the same communities using two different markers - COI and 16S - and three different sampling methods: (a) homogenized Malaise trap samples (homogenate), (b) preservative ethanol from the same samples, and (c) soil samples. Our results indicate that COI and 16S offer partly complementary information on Malaise trap samples, with each marker detecting a significant number of species not detected by the other. Different sampling methods offer highly divergent estimates of community composition. The community recovered from preservative ethanol of Malaise trap samples is significantly different from that recovered from homogenate. Small and weakly sclerotized insects tend to be overrepresented in ethanol while strong and large taxa are overrepresented in homogenate. For soil samples, highly degenerate COI primers pick up large amounts of nontarget DNA and only 16S provides adequate analyses of insect diversity. However, even with 16S, very little overlap in molecular operational taxonomic unit (MOTU) content was found between the trap and the soil samples. Our results demonstrate that none of the tested sampling approaches is satisfactory on its own. For instance, DNA extraction from preservative ethanol is not a valid replacement for destructive bulk extraction but a complement. In future metabarcoding studies, both should ideally be used together to achieve comprehensive representation of the target community.
  • Löyttyniemi, Kari (Suomen metsätieteellinen seura, 1983)
  • Löyttyniemi, Kari; Uusvaara, Olli (Suomen metsätieteellinen seura, 1986)
  • de Mendoza, Guillermo; Kaivosoja, Riikka; Grönroos, Mira; Hjort, Jan; Ilmonen, Jari; Kärnä, Olli-Matti; Paasivirta, Lauri; Tokola, Laura; Heino, Jani (2018)
    1. Metacommunity theory focuses on assembly patterns in ecological communities, originally exemplified through four different, yet non-exclusive, perspectives: patch dynamics, species sorting, source-sink dynamics, and neutral theory. More recently, three exclusive components have been proposed to describe a different metacommunity framework: habitat heterogeneity, species equivalence, and dispersal. Here, we aim at evaluating the insect metacommunity of a subarctic stream network under these two different frameworks. 2. We first modelled the presence/absence of 47 stream insects in northernmost Finland, using binomial generalised linear models (GLMs). The deviance explained by pure local environmental (E), spatial (S), and climatic variables (C) was then analysed across species using beta regression. In this comparative analysis, site occupancy, as well as taxonomic and biological trait vectors obtained from principal coordinate analysis, were used as predictor variables. 3. Single-species distributions were better explained by in-stream environmental and spatial factors than by climatic forcing, but in a highly variable fashion. This variability was difficult to relate to the taxonomic relatedness among species or their biological trait similarity. Site occupancy, however, was related to model performance of the binomial GLMs based on spatial effects: as populations are likely to be better connected for common species due to their near ubiquity, spatial factors may also explain better their distributions. 4. According to the classical four-perspective framework, the observation of both environmental and spatial effects suggests a role for either mass effects or species sorting constrained by dispersal limitation, or both. Taxonomic and biological traits, including the different dispersal capability of species, were scarcely important, which undermines the patch dynamics perspective, based on differences in dispersal ability between species. The highly variable performance of models makes the reliance on an entirely neutral framework unrealistic as well. According to the three-component framework, our results suggest that the stream insect metacommunity is shaped by the effect of habitat heterogeneity (supporting both species-sorting and mass effects), rather than species equivalence or dispersal limitation. 5. While the relative importance of the source-sink dynamics perspective or the species-sorting paradigm cannot be deciphered with the data at our disposal, we can conclude that habitat heterogeneity is an important driver shaping species distributions and insect assemblages in subarctic stream metacommunities. These results exemplify that the use of the three-component metacommunity framework may be more useful than the classical four perspective paradigm in analysing metacommunities. Our findings also provide support for conservation strategies based on the preservation of heterogeneous habitats in a metacommunity context.
  • Kauppi, Katja; Rajala, Ari; Huusela, Erja; Kaseva, Janne; Ruuttunen, Pentti; Jalli, Heikki; Alakukku, Laura; Jalli, Marja (2021)
    The effect of weeds, plant diseases and insect pests on spring barley (Hordeum vulgare) and spring wheat (Triticum aestivum) grain and nutrient yield was examined. Long-term field trial data was used to assess the impact of different pests on grain yield. In the absence of pesticides, fungal diseases caused the largest annual yield-reduction in spring wheat and spring barley, 500 kg ha(-1) on average. Converting yield loss to nutrient yield loss this represented reductions of 8.1 and 9.2 kg ha(-1) in nitrogen and 1.5 and 1.6 kg ha(-1) in phosphorus, respectively. Likewise, it was estimated that weeds decrease the yield of spring barley and spring wheat for 200 kg ha(-1), which means reductions of 3.7 and 3.2 kg ha(-1) in nitrogen and 0.6 kg ha(-1) in phosphorus, respectively. For insect pests yield-reduction in spring barley and spring wheat varied between 418 and 745 kg ha(-1) respectively. However, because bird cherry-oat aphid (Rhopalosiphum padi L.) incidence data was limited, and aphids are highly variable annually, nutrient yield losses caused by insect pests were not included. Based on the current study, the management of weeds, plant diseases and insects maintain cereal crop yield and may thus decrease the environmental risks caused by unutilized nutrients.
  • Toivonen, Marjaana; Herzon, Irina; Toikkanen, Jenni; Kuussaari, Mikko (Enviroquest, 2021)
    Journal of Pollination Ecology 28, 153-166
    Uncultivated field margins are important refugia for pollinating insects in agricultural landscapes. However, the spill-over of pollination services from field margins to adjacent crops is poorly understood. This study (i) examined the effects of landscape heterogeneity on pollinator occurrence in permanent field margins and pollinator visitation to adjacent mass-flowering turnip rape (Brassica rapa ssp. oleifera) in boreal agricultural landscapes, and (ii) tested whether pollinator abundance and species richness in field margins predict abundance and species richness of crop visitors. Pollinators visiting the crop were more affected by landscape heterogeneity than pollinators in adjacent margins. Species richness, total abundance, and the abundance of syrphid flies visiting the crop increased with increasing landscape heterogeneity, whereas, in field margins, landscape heterogeneity had little effect on pollinators. In field-dominated homogeneous landscapes, wild pollinators rarely visited the crop even if they occurred in adjacent margins, whereas in heterogeneous landscapes, differences between the two habitats were smaller. Total pollinator abundance and species richness in field margins were poor predictors of pollinator visitation to adjacent crop. However, high abundances of honeybees and bumblebees in margins were related to high numbers of crop visitors from these taxa. Our results suggest that, while uncultivated field margins help pollinators persist in boreal agricultural landscapes, they do not always result in enhanced pollinator visitation to the adjacent crop. More studies quantifying pollination service delivery from semi-natural habitats to crops in different landscape settings will help develop management approaches to support crop pollination.
  • Lahti, Tuomas (Helsingfors universitet, 2014)
    The purpose of this master's thesis was to study environmental impacts of nature-based tourism on vegetation, insect communities, birds and soil nitrogen levels in Käsivarsi wilderness area in the Finnish Lapland. Tourism is the largest industry in the world and nature-based tourism is the fastest growing segment of it. Nature-based tourism takes place in areas that holds great nature values. These areas are often protected to preserve significant nature values from negative impacts of human activities. This controversy creates disharmony between nature tourism and nature conservation. Most popular nature tourism destinations in Finland are state owned national parks and wilderness areas. Wilderness areas are not within strict nature conservation. They are areas defined by law for preserving the typical character of the remaining wilderness areas, preserving native Saami culture and for preserving and developing recreational use of these areas. Studies have shown that nature-based tourism has caused changes by erosion and human disturbance to vegetation, mammals and birds. The key study question was to examine if there are changes in the soil nitrogen levels around huts used by hikers. I was also a point of interest to discover what kind of bird, insect and plant communities occur around these huts. Main interest was to see if there are changes in these communities on a gradient from high human impact areas around the huts to more pristine mountainous areas. The study was performed around five huts with three study lines, which had study points 15, 30, 60, 120, 240, 480 and 960 meters away from the hut. Birds were observed from the same lines but with 200 meter point counting intervals. It was also studied whether the abundance of graminoids was affected by the soil nitrogen levels and if soil nitrogen levels or the abundance of graminoids influenced changes in insect or bird communities. Results show that nature-based tourism has an impact on soil ammonium and nitrate levels. This impact was visible in increased nitrate and ammonium levels on a 30 meter radius area around the huts. The observed fauna and flora around the huts were typical for the mountainous region in the northern Finland. There were no observed invasive species. No species was discovered to have a negative impact from nature-based tourism. Abundance of graminoids increased near the huts whereas plant species richness and vegetation biomass did not. The insect community was more diverse and abundant near the huts. Especially Amara brunnea ground beetle and rove beetles showed a clear increase in numbers near the huts. Birds were also more abundant and species rich near the huts. Especially insect eating bird species as a group were more abundant close to the hut compared to the surrounding study areas. The increased level of ammonium in the soil correlated with the increased graminoid and insect abundances. The increased graminoid abundance correlated also with the observed insect abundance. The influence between nature-based tourism and the changes in soils nitrogen levels and in the insect communities were scientifically demonstrated for the first time in this study. This thesis provides a comprehensive view of the effects that nature-based tourism has in the northern Finnish nature. The generalization of the result was weakened by the fact that the study was conducted only around five different huts and that the studied plant and animal communities were relatively diverse between these huts. The results are still substantial for the nature tourism in Käsivarsi wilderness area. The results can be useful for developing nature tourism infrastructure for the plausible new national park in the area.
  • Kohonen, Ilmari (Helsingin yliopisto, 2020)
    Global biodiversity continues to decline. Recent reports of decline in insect abundance and biomass are concerning, given the crucial roles insects play in multiple ecosystem processes, such as pollination, nutrient cycling and as a food resource for higher trophic levels. Based on the current state of the literature, it appears that total insect abundance and biomass are in decline, but there is considerable variation in trajectories in different regions and taxa. Many studies report on either aggregated community abundance or biomass, but few have examined how closely these two variables are correlated. For example, declining trends in large-bodied species could have disproportionately large effects on total biomass, even if total abundance remained stable. This, in turn, could have substantial consequences for predators dependent on insect biomass for food. Whether studying total abundance or biomass, long-term monitoring data are essential for robust estimation of temporal trends. In my thesis, I investigated trends in macro-moth abundance and biomass using data from the Finnish moth monitoring scheme (Nocturna) over a period of 24 years (1993-2016). My main objectives were to explore whether total abundance and biomass have changed over the timeframe examined, and to estimate the degree of correlation between the two variables in these data. As is typical for monitoring programs, only counts of moth individuals have been recorded. In order to obtain information on biomass, I created a predictive model for converting the recorded abundance counts to dry biomass based on species mean wingspan and body robustness. I weighed museum collection specimens of common moth species of variable sizes, and used these data for fitting the model. Additionally, I also investigated how local weather (thermal and precipitation) conditions during the growing season and winter relate to interannual variation in total abundance. Finally, I analysed potentially informative species traits (e.g., wingspan, voltinism, overwintering stage) in relation to population trends of individual species, because such associations could be underlying change in total abundance or biomass. There was no long-term change in total macro-moth abundance or biomass over the 24-year monitoring period. Abundance and biomass were very highly correlated (r > 0.9). In terms of interannual variation, total moth abundance and biomass showed a distinctive pattern suggestive of periodicity, with peaks at approximately 10-year intervals. Local weather conditions were very weakly associated with annual change rates of total abundance, leaving the interannual pattern unexplained. Lichen-feeding and multivoltinism (multiple generations per year) were positively related to population trends, supporting earlier findings. Especially relevant to potential trends in biomass, wingspan showed no relationship with positive or negative trends, which is in line with the high correlation between abundance and biomass in this dataset. My results imply that the total abundance and biomass trends in boreal Europe diverge from those commonly reported from temperate Europe. Further research is required to shed light on factors underlying total insect abundance and biomass trends. The method I developed for converting moth abundance to biomass is applicable to similar work elsewhere.
  • Meinader, Martin; Panelius, Samuel (Societas entomologica Helsingforsiensis, 1970)
    Notulae entomologiae; 50
  • Meinander, Martin; Panelius, Samuel (Societas entomologica Helsingforsiensis, 1971)
    Notulae entomologiae; 51
  • Meinander, Martin (Societas entomologica Helsingforsiensis, 1972)
    Notulae entomologiae; 52
  • Meinander, Martin (Societas entomologica Helsingforsiensis, 1973)
    Notulae entomologiae; 53
  • Meinander, Martin (Societas entomologica Helsingforsiensis, 1974)
    Notulae entomologiae; 54
  • Meinander, Martin; Panelius, Samuel (Societas entomologica Helsingforsiensis, 1975)
    Notulae entomologiae; 55
  • Meinander, Martin (Societas entomologica Helsingforsiensis, 1976)
    Notulae entomologiae; 56