On the generalized Feng-Rao numbers of numerical semigroups generated by intervals

We give some general results concerning the computation of the generalized Feng-Rao numbers of numerical semigroups. In the case of a numerical semigroup generated by an interval, a formula for the $r^{th}$ Feng-Rao number is obtained.Comment: 23 pages, 6 figure

Educació i drogues, drogues i educació?

Hem volgut obrir aquesta tribuna amb un interrogant sense cap pretensió d'oferir una resposta, sinó de plantejar les suficients incógnites, dubtes i vacil'lacions que siguin necessaries per tal de suscitar reflexió i debat. Només d'aquesta manera, creiem -i, de fet, n'estem convenc;: udes-, que podrem avanc;:ar paral'lelament i en consonancia amb una realitat social tan heterogénia i canviant. Partim d'algunes consideracions al voltant de I'educació amb les quals ens identifiquem per intentar establir una relació entre aquest instrument de socialització i les drogues com un fenomen social

Evaluating historical, basin-wide landslide activity in a context of land abandonment and climate change: Effects of landslide visibility and temporal resolution

Drainage basins of the Northern Apennines, particularly in the clayey settings, bear among the highest rates of landsliding worldwide. A history of major land cover changes has left a landscape characterized by sparse, coppice-managed forest, transitional shrubs, and actively eroding badlands. Historical trends of landslide occurrence are examined in the Sillaro River basin (139 km2) in relation to land cover and climatic changes. To this purpose we have compiled a multi-temporal (1954–2018) landslide inventory (n = 1164) across twelve sequential photo sets that bears decadal (7- to 15-yr) and finer (2- to 6-yr) temporal resolution respectively before and after 1996. To account for changes in meteorological forcing, we examine: (i) the total annual precipitation (PRCPTOT); (ii) the annual maximum daily precipitation (RX1day); and (iii) the precipitation fraction (R99pTOT) due to extremely wet days. We find that landslide activity is strongly controlled by lithology, with landslide densities in claystones 3-to-4 times higher than in marl-sandstone alternations. This difference is chiefly associated with badlands, which are the most active land cover type and where new scars at a site could recur up to nine times. To evaluate the influence of varying temporal resolution on inventory completeness, hence on inference about land cover and climatic effects, we constrain the time scales of landslide visibility and assess the relative rates of undersampling. We find that visibility functions decline non-linearly with time, and that an inventory compiled at 5-year resolution would be missing up to 20 % of the landslide scars, with the size of an additional 27 % that would be underestimated due to revegetation. Overall, detection of entire landslide scars, which varies with land cover, becomes rare after 13 years in transitional shrubs, and after 17 years in badlands and managed forest. The historical analysis shows that landslide count: (i) increases in 1955–1976, a period of maximum anthropogenic pressure and wetter conditions; (ii) decreases steadily from 1977 through 2000, during a phase of land abandonment and decline in annual precipitation; and (iii) grows highest in 2000–2014, a period of land cover stability characterized by lesser precipitation although increasingly focused on high-magnitude events. To evaluate the likely reason of this recent increase in landsliding (i.e., R99pTOT vs inventorying resolution), we replicate the post-1996 mapping at coarser resolution. In the simplified inventory, landslide densities drop up to a factor of 2, and the inverse correlation originally linking landslide count with R99pTOT, loses significance. We conclude that, when the bias associated with varying inventorying resolution is removed, dependencies previously attributed to climatic effects become drastically reduced, and in some instances can even disappear

The effects of land use and topographic changes on sediment connectivity in mountain catchments

Understanding the evolution of sediment connectivity associated with different land use and topographic changes is a prerequisite for a better understanding of sediment budgets and sediment transport processes. We used the Index of Sediment Connectivity (IC) developed by Cavalli et al. (2013) based on the original approach by Borselli et al. (2008) to study the effects of decadal-scale land use and topographic changes on sediment connectivity in mountain catchments. The input variables of the IC (i.e. land cover and topography) were derived from historical aerial photos using Structure from Motion-Multi View Stereo algorithms (SfM-MVS). The method was applied in different sub-catchments of the Upper River Cinca Catchment (Central Pyrenees), representative of three scenarios: (a) Land cover changes; (b) Topographic changes in agricultural fields (terracing); and (c) Topographic changes associated with infrastructure (road construction). In terms of land cover changes, results show that although connectivity is increased in some areas due to the establishment of new field crops, for most of the study area connectivity decreased due to afforestation caused by rural abandonment. Topographic changes due to the establishment of agricultural terraces affected connectivity to a larger degree than land cover changes. Terracing generally reduced connectivity due to the formation of flat areas in step-slopes, but in certain points, an increase in connectivity caused by the topographic convergence produced by terraces was observed. Finally, topographic changes associated with road construction greatly modified surface flow directions and the drainage network, resulting in changes in connectivity that may affect erosional processes nearby. The methodology used in this paper allows to study the effects of real decadal-scale land use and topographic changes on sediment connectivity and also evaluating and disentangling those changes. Furthermore, this approach can be a useful tool to identify potential risks associated with morphological and land use changes, involving road infrastructures

Accounting for Carbon Footprint Flows in Wine Production Process. Case Study in Spanish Winery

Companies are gradually becoming conscious about the necessity of reducing their environmental impact and adopting low-carbon strategies in order to cope with increasing institutional and social demands. However, remaining competitive while reducing the environmental impact and improving the corporate image requires adopting sophisticated mechanisms boosting eco-efficiency and keeping costs tight. Material Flows Cost Accounting (MFCA) is an instrument that allows the monitoring of, measurement of, and accounting for physical and monetary processes along the production process. If extended to the supply chain, and applied to the energy usage and CO2 emissions, it allows one to account for the Carbon Footprint (CF) of a company and its products at any given stage of the value chain. The current paper presents a case study developed under the framework of a three-year project to introduce an energy use and carbon emissions monitoring and accounting system in a large winery company in Spain, based on the MFCA approach and CF accountability. Including the supply chain of the company and the whole farming cycle of its main input, the case study presents the method and phases adopted to implement the project, its direct and indirect results and outcomes, and the conclusions that can be extracted, which may be inspirational for practitioners and scholars envisaging similar projects

¿Reportar mediciones o midiendo para reportar? Medición interna de la Economía Circular desde una perspectiva de la contabilidad medioambiental y su interrelación

This paper aims to provide a model to measure the circular economy in businesses from an environmental accounting approach. The range of circular activities and the intensity with which companies implement them are analysed to increase the understanding of the relationship between the implementation of circular economy in firms and their different environmental management accounting and reporting practices. The study is developed through an empirical analysis based on a survey addressed to a sample of Spanish companies and designed to analyse different environmental accounting practices and measure the circular economy-related activities introduced by companies to close the material loops in processes. Main results indicate that circular economy activities are generally introduced by companies progressively, without clearly responding to common patterns for the introduction of the different circular principles and activities. A moderate correlation is observed between companies’ level of circular economy and their environmental management accounting practices, with a more significant correlation for a higher number of circular activities, particularly for firms that implement environmental management systems and have higher levels of transparency and sustainability information policies. Although companies are progressively adopting circular activities, the lack of specific indicators limits their internal measurement. Consequently, the information provided by organisations about the closing of material loops remains sporadic. The results highlight the need for built-in specific metrics to deploy environmental accounting practices in circular economy models.Este trabajo presenta un modelo para medir la economía circular en las empresas desde un enfoque de contabilidad medioambiental. Se analizan tanto el rango de actividades circulares como la intensidad con la que son implementadas para contribuir al conocimiento de la relación entre la introducción de la economía circular en las empresas y sus prácticas de contabilidad e información de gestión medioambiental. El estudio se desarrolla a través de un análisis empírico llevado a cabo a través de una encuesta dirigida a una muestra de empresas españolas diseñada para analizar las prácticas de contabilidad e información medioambiental y de medición de las actividades relacionadas con la economía circular introducidas por las empresas en sus procesos de cierre de círculos de materiales. Los principales resultados obtenidos indican que las actividades de economía circular son generalmente introducidas por las empresas progesivamente, sin responder de forma clara a paulas relacionadas con los distintos principios y actividades circulares. Se observa una correlación moderada entre el nivel de circularidad de las empresas y sus prácticas de contabilidad de gestión medioambiental, siendo la correlación mayor a mayor número de actividades, especialmente en lo que concierne a la implementación de sistemas de gestión ambiental o el desarrollo de políticas de transparencia y de información de sostenibilidad. A pesar de que las empresas estén adoptando progresivamente actividades circulares, la falta de indicadores específicos limita la medición interna de la economía circular por parte de las empresas. Por consiguiente, la información proporcionada por las organizaciones acerca del cierre de círculos sigue siendo esporádica. Los resultados ponen de manifiesto la necesidad de métricas integradas específicas para el despliegue de prácticas de contabildiad medioambiental para modelos de economía circular