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In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

This paper deals with waste management in the tourism sector, specifically in the agro-tourism structures. Two regions of Romania and Italy have been considered as case studies in order to promote good practices and actions for sustainable municipal solid waste management. Specific criteria to adopt for the sustainable consumption of beverages and food and for the sustainable use of packaging of various types have been analyzed and suggested. The adoption of an indicator at the level of the single tourist structure has been proposed to help self-analysis that is aimed at setting the priorities of intervention for improving its environmental sustainability.

The biological denitrification process is extensively discussed in scientific literature. The process requires anoxic conditions, but the influence of residual dissolved oxygen (DO) on the efficiency is not yet adequately documented. The present research aims to fill this gap by highlighting the effects of DO on the specific denitrification rate (SDNR) and consequently on the efficiency of the process. SDNR at a temperature of 20 °C (SDNR20°C) is the parameter normally used for the sizing of the denitrification reactor in biological-activated sludge processes. A sensitivity analysis of SNDR20°C to DO variations is developed. For this purpose, two of the main empirical models illustrated in the scientific literature are taken into consideration, with the addition of a deterministic third model proposed by the authors and validated by recent experimentations on several full-scale plants. In the first two models, SDNR20°C is expressed as a function of the only variable food:microrganism ratio in denitrification (F:MDEN), while in the third one, the dependence on DO is made explicit. The sensitivity analysis highlights all the significant dependence of SDNR20°C on DO characterized by a logarithmic decrease with a very pronounced gradient in correspondence with low DO concentrations. Moreover, the analysis demonstrates the relatively small influence of F:MDEN on the SDNR20°C and on the correlation between SDNR20°C and DO. The results confirm the great importance of minimizing DO and limiting, as much as possible, the transport of oxygen in the denitrification reactor through the incoming flows and mainly the mixed liquor recycle. Solutions to achieve this result in full-scale plants are reported.

Abstract:The paper retraces the implementation of a biogas energy programme within the Best Ray project run in Tanzania 2008-2011. The objective of the Best Ray project was to empower rural communities by providing them with modern and renewable energy technologies to better tackle Millennium Development Goals. An important activity of the project was the construction of a biogas system in secondary school solve a sanitation problem and provide the school with a free and reliable energy supply. After a field assessment, the project directed the resources to small domestic biogas installation rather than large institutional ones as future sustainability seemed to be better granted. Best Ray merged the Tanzanian Domestic Biogas Programme. Trainings were organized and 25 biogas plants constructed. The technology is simple and the design effective, but still the cost seems high for a rural context. Final beneficiaries are appreciating the technologies for reasons that were not predictable by those who ideated the project.