6 research outputs found

    Monitoring of aphid flight activities in seed potato crops in Serbia

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    Aphid flight activities in seed potato fields have been studied by the yellow water traps. It is a good method for monitoring aphids as vectors of viruses, but this study also showed it is a suitable method for insect-diversity research. During the four-year studies, over 11.500 specimens were collected and a total of 107 different taxa of aphids were identified. The most abundant species were polyphagous species, such as: Acyrthosiphon pisum (Haris), Aphis fabae Scopoli, Aphis gossypii Glover and Brachycaudus helichrysi (Kaltenbach). The results of the studies show that diversity of aphids in different regions of Serbia is similar regardless of the altitude and the diversity of terrain. At most sites it ranged from 2 to 3. The highest value was recorded in Begec, locality in northern part of Serbia, in year 2008, and it was 2.92. The maximum values of the Shannon-Weaver diversity index at all sites were recorded in the first weeks of the monitoring of aphid flight activities. Morisita-Horn similarity index shows no significant differences between sites regardless of altitudes. The sites are grouped by year, not by similarity of relief. In spite of these results, the Chi-square analysis showed highly significant difference in vector frequencies among seasons and sites with more pronounced differences for PVY. As a consequence of differences in vector frequencies, the vector pressure index in some regions was different also. The number of vectors and vector pressure index vary depending on the altitude of localities. At localities at altitudes under 1000 m, they were high. The highest index was at Kotraza, locality in central part of Serbia, in 2007, when PVY index exceeded the value of 180, while for PLRV it was 60. At high altitudes on mountain Golija, above 1100 m, the number of aphids was low, as well as the vector pressure index which indicates that these regions are suitable for producing virus-free seed potato

    Report on the Workshop on Transversal Variables. (Linking economic and biological effort data (call) design). 19th -23rd January 2015

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    The Workshop on the Transversal Variables took place in Zagreb from the 19th to 23rd of January, 2015 mainly to tackle the issues related to the increasing need of having fisheries fleet economic data and fisheries biologic data on a level of disaggregation that would allow a proper interoperability between datasets to underpin bioeconomic modelling. For that, several analyses were carried out and conclusions taken. These analyses were : 1. comparison of economic and biological effort data calls both with respect to their level of resolution and the landings and effort values obtained from equivalent aggregations was performed. This was compared to what would be needed in order to undertake bioeconomic modelling for a chosen management plan. 2. The description of how MS are calculating effort variables and a proposal on the way forward to harmonize approaches, 3. Conclusions on how to harmonize levels of resolution, the variable definitions and the codification in use amongst data calls, in order to make them comparable and based on coherent standard codifications.JRC.G.3-Maritime affair

    The influence of filler on the properties of elastomeric materials based on poly(ethylene-co-propylene-co-2-ehylidene-5-norbornene) rubber

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    Crosslinked samples based on poly(ethylene-co-propylene-co-2-ehylidene5-norbornene) EPDM rubber, carbon black as active filler and natural chalk as inactive filler were cured with sulphur. The content of carbon black was varied from 100 to 200 pph. The content of chalk was varied from 0 to 100 pph. The content of paraffin oil was also varied in some samples. The compounds were prepared by mixing ingredients on a laboratory two-roll mill. Vulcanizates were prepared by curing at 180°C. Various methods were used for the physical and mechanical characterizations. The dynamic mechanical properties of the elastomers were measured in the temperature range from -120 to 80°C

    The economic performance of the EU fishing fleet during the COVID-19 pandemic

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    The COVID-19 outbreak and subsequent public health interventions have depressed demand and disrupted supply chains for many fishing businesses. This paper provides an analysis of the COVID-19 impacts on the profitability of the EU fishing fleets. Nowcasting techniques were used to estimate the impact of the COVID-19 pandemic on the economic performance for the EU fishing fleet in 2020 and 2021. Our results show that the economic impact of COVID-19 on this sector was smaller than initially expected and overall profits remained positive. This was in part due to low fuel prices that reduced operating costs of fishing, and the early response from governments to support the sector. The results vary by fishing fleet, revealing that small-scale fleets and the fleets in the Mediterranean and Black seas have been more impacted than large-scale fleets and the fleets in the Northeast Atlantic

    The economic performance of the EU fishing fleet during the COVID-19 pandemic

    No full text
    The COVID-19 outbreak and subsequent public health interventions have depressed demand and disrupted supply chains for many fishing businesses. This paper provides an analysis of the COVID-19 impacts on the profitability of the EU fishing fleets. Nowcasting techniques were used to estimate the impact of the COVID-19 pandemic on the economic performance for the EU fishing fleet in 2020 and 2021. Our results show that the economic impact of COVID-19 on this sector was smaller than initially expected and overall profits remained positive. This was in part due to low fuel prices that reduced operating costs of fishing, and the early response from governments to support the sector. The results vary by fishing fleet, revealing that small-scale fleets and the fleets in the Mediterranean and Black seas have been more impacted than large-scale fleets and the fleets in the Northeast Atlantic
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