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Item Proposal of two visual tree risk assessment methods for urban parks in Montevideo, UruguayAutores: Coelho-Duarte, Ana Paula; Daniluk-Mosquera, Gustavo; Gravina, Virginia; Hirigoyen, Andrés; Vallejos-Barra, Oscar; Ponce-Donoso, MauricioThe risk assessment of urban trees is a challenge that must be addressed by many cities, in consideration of their climatology, management and spatial heterogeneity. Since these trees are in stages of aging, added to bad practices, inadequate selection and establishment, amongst others, their early elimination, and hence the loss of the ecosystem services they provide, is being promoted. For this reason, two tree risk assessment methods were developed to be applied in a complementary manner in urban parks, one basic visual (BV) and the other detailed visual (DV), both structured with the components of likelihood of failure, likelihood of impact, consequence and risk rating, being analyzed qualitatively and semi quantitatively. The methods were applied in 24 trees of Eucalyptus and Tipuana genus by two groups of assessors, experienced and inexperienced, totaling 192 assessments. Results were analyzed with a linear mixed model (LMM), which showed differences between both methods for the likelihood of failure, where the assessment of branches turned out to be the attribute with the highest impact. The methods proved to be suitable to be used in a complementary manner, since BV turns out to be efficient when it is necessary to assess a large number of trees. DV turned out to be more effective, since it was able to identify more precisely the attributes of the tree that must be considered for adequate risk mitigation and management. Therefore, their combined use is recommended for risk assessment in trees established in parks.Item Nutrient (N, P, K) use efficiency and nitrogen balance in a bioenergy plantation of Populus deltoides clone Lux in San Piero A Grado (Pisa), ItalyAutores: Ariza, Antonio María Cabrera; Ragaglini, Giorgio; Silva-Flores, Patricia; Bustos-Letelier, Oscar; Santelices-Moya, RómuloEnergy crops have proved to be a viable alternative to fossil fuels. However, high biomass production always means that large quantities of nutrients from the soil are removed at harvest. The goal of this work was to estimate nutrient (nitrogen, phosphorous, potassium) use efficiency (NUE) and nitrogen balance in an eight-year-old Populus deltoides clone Lux, short rotation forestry under two cutting cycles, every two (biennial) and three (triennial) years, carried out under Mediterranean climate conditions. Results indicate that NUE, for all the analyzed elements, contained variations with slightly higher values for nitrogen and phosphorous in the triennial cycle. Although poplar cultivation has a positive nutrient efficiency, in terms of nitrogen, there is significant loss of this element in the crop cycle.Item Green bonds, sustainable development and environmental policy in the European Union carbon marketAutores: Leitao, Joao; Ferreira, Joaquim; Santibánez González, ErnestoThis study assesses the non-linear effects of green bonds, conventional bonds and energy commodities on the behaviour of the cap-and-trade European Union carbon market (European Union Emissions Trading System [EU-ETS]). By estimating four models, using Markov-switching (MS) econometric methodology, non-linearities are confirmed in dynamic behaviours, observing in the global calculation a positive effect of green bonds (S&P Green and Sol Green) on the carbon market, in regimes of both high and low volatility, whereas conventional bonds (S&P Agg) and energy commodities (DJCI En) contribute to a decrease in the carbon market in regimes of high volatility. The relevance of green bonds is underlined in determining the behaviour of the carbon market, besides observing greater persistence of the low volatility regime. These results allow both investors and fund managers to implement strategies in different volatility or economic activity contexts through a diversified portfolio and green/climate structure.
