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The present study investigated the effects of cultivation practices on grain (oats) yield and yield components, such as straw yield, harvest index, thousand kernel weight, and plant lodging. In addition, multi-element composition and isotopic signature (δ13C, δ15N) of the oat grains were studied. The spring oat cultivar ‘Noni’ was grown in a long-term field experiment during 2015–2020, using three management practices: control without organic amendment, incorporation of manure every third year and incorporation of crop residues/cover crop in the rotation. Synthetic nitrogen (N) (0, 55, 110 and 165 kg/ha) was applied during oat development in each system. Multi-element analysis of mature grains from two consecutive years (2016 and 2017) was performed using EDXRF spectroscopy, while stable isotope ratios of carbon (C) and nitrogen (N) were obtained using an elemental analyzer coupled to an isotope ratio mass spectrometer (EA/IRMS). The results show how cultivation practices affect yield components and isotopic and elemental signatures. Increasing the N rate improved both the oat grain and straw yields and increased susceptibility to lodging. The results show how the elemental content (Si, Ca, Zn, Fe, Ti, Br and Rb) in the oat grains were influenced by intensification, and a noticeable decrease in elemental content at higher N rates was the result of a dilution effect of increased dry matter production. The mean δ15N values in oat grains ranged from 2.5‰ to 6.4‰ and decreased with increasing N rate, while δ13C values ranged from −29.9‰ to –28.9‰. Based on the δ15N values, it was possible to detect the addition of synthetic N above an N rate of 55 kg/ha, although it was impossible to differentiate between different management practices using stable isotopes.

The Authors conducted a long-term follow-up study of a John Deere 1490 forwarder-mounted bundler owned by a Portuguese company and used for bundling logging residues from fast-growing eucalypt plantations located in Portugal and Spain. The study spanned 7 years, from 2011 to 2016. During this time, the machine clocked over 11,500 h and produced more than 200,000 bundles or 75,000 green tons of biomass. Bundle length was commonly 2.4 m, and bundle mass averaged 350 kg. Overall, the database contained 1752 daily records. Bundling productivity averaged 19 bundles per productive machine hour (meter hour, excluding all major delays). Mechanical availability was very high and averaged 93%. Utilization commonly ranged between 65% and 75%. Use and productivity showed a predictable seasonal trend and a slight decline over time. The latter might be due to wear, but also due to the increasingly challenging conditions faced by the company as the average worksite size sharply decreased from 2011 onwards. While almost extinct elsewhere, bundling seems to thrive in the Iberian plantations, possibly due to the industrial character of both eucalypt farming and bioenergy generation in the region. That allows the reaping of all integration benefits offered by bundling, while the cost of setting up a parallel biomass chain is minimized. Furthermore, bundling seems the ideal technique for efficient residue recovery where slash yields are low and roadside storage space is limited: these are the typical constraints of industrial eucalypt plantations, where planted area is maximized (=little landing space) and the largest possible proportion of the tree mass is turned into pulpwood (=relatively low residue yield).

Diplomsko delo obravnava donose plodov, lesa in medu evropskega pravega kostanja (Castanea sativa Mill.) v Beli krajini. Raziskovalni objekt se nahaja v gozdnogospodarski enoti Črnomelj. Podatki o donosih plodov kostanja so bili pridobljeni na dvajsetih vzorčnih ploskvah, ki so bile locirane na mreži 100 × 100 m. Ocenjene in izmerjene so bile tudi nekatere sestojne značilnosti in lastnosti dreves, pod katerimi smo inventarizirali plodove. S pomočjo teh podatkov so bile narejene primerjave glede vplivov posameznih parametrov na donos plodov. Pridobljeni ali izračunani so bili tudi podatki o donosih kostanjevega medu in lesa. Na vzorčnih ploskvah je bilo v povprečju 390 g zdravih kostanjevih plodov, kar predstavlja donos 487,5 kg/ha. Najnižji donos je znašal 254 g (318 kg/ha), najvišji pa 649 g (811 kg/ha). Vrednost donosa plodov se je glede na zbrane podatke in tržno ceno gibala med 975 in 1706 €/ha/leto. Donos končnega poseka bi predstavljal 6087 €/ha ± 4062 €/ha. Donos volumenskega prirastka lesa je bil ob 1 - 4 % relativnem volumenskem prirastku lesne zaloge kostanja ocenjen na 37,2 - 148,7 €/ha/leto. Vrednost ocenjenega donosa medu je znašala 300 - 540 €/ha/leto. Zaključeno je bilo, da bi donos s strani plodov tudi v najslabšem primeru skoraj 7 krat presegel prihodek s strani letnega volumenskega prirastka kostanja. The thesis deals with the yields of fruits, wood and honey of the sweet chestnut (Castanea sativa Mill.) in Bela krajina. The study area is located in the forest management unit Črnomelj. Data on chestnut fruit yields were obtained on twenty sample plots located on a 100 × 100 m grid. Some stand characteristics and properties of trees, under which fruits were inventoried, were assessed and measured. These data enabled analyses of their influence on fruit yield. Data on chestnut honey and timber yields were also obtained or calculated. On the sample plots, an average of 390 g of healthy chestnuts was obtained, which represents a yield of 487.5 kg/ha. The lowest yield was 254 g (318 kg/ha) and the highest 649 g (811 kg/ha). According to these results and the market price, the value of fruit yield ranged between 975 and 1706 €/ha/year. The value of the final felling timber yield would represent 6087 €/ha ± 4062 €/ha. The value of the wood volume increment was estimated at 37.2 - 148.7 €/ha/year at 1 - 4 % relative volume increment of chestnut growing stock. The value of the estimated yield of sweet chestnut honey was 300-540 €/ha/year. It was concluded that even in the worst case scenario the value of the sweet chestnut fruit yield would be almost 7 times higher than the income from the annual wood volume increment.

Background and Purpose: In recent years classic financial market theory based on decision makers’ rationality has been challenged by repeated anomalies that became a ‘new normal’. As a result, what we witness today is a considerable turn to behavioral concepts that can shed a new light on choices made by market participants. The astonishing development of social media accelerated scientific validation of such concepts, since the media opened new and capacious ‘laboratory space’ for testing behavioral hypotheses. The main purpose of the article is to examine whether financial market professionals believe that social media content can be useful in achieving additional financial market returns and to investigate the factors behind this belief. Design/Methodology/Approach: We surveyed a sample of over 400 financial market professionals at institutions operating in Poland, and analyzed the results using logit regression models. Results: We established that almost 60% of the surveyed finance professionals recognized the potential of social media for achieving additional returns. We also found out that the differences in respondents’ perception of this potential could be explained mainly by heterogeneity of their job experience and, to a lesser degree, by their job position. Interestingly, more experienced individuals were less likely to recognize this potential. Firm-specific factors did not have a significant effect on the dependent variable. Conclusion: The opinions of financial market professionals regarding the link between social media and additional returns are mixed, which is consistent with the current body of evidence brought by sentiment-based research. Our findings confirm the key role of previous experience in explaining attitudes towards novelties and innovations (such as social media), a phenomenon known from other fields and everyday experience. Ozadje in namen: V zadnjih letih se je pokazalo vse več dvomov v ustreznost klasične teorije finančnih trgov, ki temelji na racionalnosti odločevalcev. Ponavljajo se anomalije in odstopanja od te teorije, ki postajajo »nova normal­nost«. Zato strokovnjaki posvečajo vse več pozornosti vedenjskim konceptom, ki se lahko z drugega vidika osvetlijo odločitve udeležencev na finančnem trgu. Hitri razvoj družbenih medijev je spodbudil raziskave, ki bi proučevale takšne koncepte, saj so mediji odprli nov “laboratorijski prostor” za preverjanje vedenjskih hipotez. Glavni namen članka je preučiti, ali strokovnjaki na finančnem trgu verjamejo, da je mogoče vsebine družbenih medijev uporabiti za doseganje dodatnih donosov na finančnih trgih, in identificirati dejavnike, ki vplivajo na te donose. Zasnova / metodologija / pristop: V raziskavi smo zajeli vzorec več kot 400 strokovnjakov na finančnih trgih v insti­tucijah, ki delujejo na Poljskem, in analizirali rezultate z uporabo logit regresijskih modelov. Rezultati: Skoraj 60% anketiranih finančnih strokovnjakov prepoznava potencial družbenih medijev za doseganje dodatnih donosov. Ugotovili smo tudi, da bi lahko razlike v zaznavanju tega potenciala pojasnila predvsem heterog­enost njihovih delovnih izkušenj in, v manjši meri, njihovo delovno mesto. Pokazalo se je, da izkušeni strokovnjaki manj verjetno prepoznajo te možnosti manj izkušeni posamezniki. Za posamezna podjetja specifični dejavniki po naših ugotovitvah nimajo pomembnega vpliva na dodatne donose. Zaključek: Mnenja strokovnjakov na finančnih trgih glede povezave med družbenimi mediji in dodatnimi donosi, so mešano. To se sklada z ugotovitvami, ki jih so jih prinesle študije, ki temeljijo na raziskovanju občutkov.. Naše ugoto­vitve potrjujejo ključno vlogo predhodnih izkušenj pri pojasnjevanju odnosa do novosti in inovacij (kot so družbeni mediji), pojav, znan iz drugih področij in iz vsakdanjih izkušenj.

Este artigo pretende explicitar como os araweté – falantes de uma língua tupi-guarani que habitam a região do Médio Xingu, na Amazônia brasileira – concebem e acessam os vegetais, tendo como referência dinâmicas relacionais e sistemas de significados que os envolvem. Para abordar essa discussão serão privilegiados os marcadores plantado e não plantado e a noção de maestria. This article aims to make explicit how the Araweté – speakers of a Tupi-Guarani language inhabiting in the Middle Xingu region of the Brazilian Amazon – conceive and access vegetable elements, with reference to relational dynamics and meaning systems involving them. To address this discussion, the planted and non-planted markers, as well as the notion of mastery, will be explored.