The concept of sustainability has gone far beyond the issues of the sustainable management of natural and environmental resources. Nowadays, sustainability is part of the social sciences in a different way. The aim of this research was dual. Firstly, we analyzed the different contexts and areas of knowledge where this concept is used in society by using social listening on Twitter, one of the most popular social networks today. The sentiments of these conversations were rated to assess whether the feelings and perceptions of these conversations on the social network were positive or negative regarding the use of the concept. Also, we tested if these perceptions about the topic were attuned to other more formal fields, such as scientific research, or strategies followed nationally or internationally by agencies and organizations related to sustainability. The method used on this first part of the research consisted of an analysis of 15,000 tweets collected from Twitter using natural language processing (NLP) for clustering the main areas of knowledge of topics where the concept of sustainability was used, and the sentiment of these conversations on the social network. Secondly, we mapped the social network of users who generated or spread content regarding sustainability on Twitter within the period of observation. Social network analysis (SNA) focuses on the taxonomy of the network and its dynamics and identifies the most relevant players in terms of generation of conversation and also their referrers who spread their messages worldwide. For this purpose, we used Gephi, an open source software used for network analysis and visualization, that allows for the exploration and visualization of large networks of any kind, in depth. The findings of this research are new, not only because of the mix of technology and methods used for extracting data from Twitter and analyzing them from different perspectives, but also because they show that social listening is a powerful method for analyzing relevant social phenomena. Listening on social networks can be used more effectively than other more traditional processes to gather data that are more costly and time consuming and lack the momentum and spontaneity of digital conversations.

COVID-19 has profoundly disrupted national education systems, affecting the future well-being of school-age children. Bacher-Hicks and colleagues showed that the intensity of the search for online learning resources in the United States doubled with respect to pre-COVID-19 levels. However, areas of the country with higher incomes, better internet access, and fewer rural schools experienced significantly greater increases in search intensity. Using a similar method to study the case of Spain, we analyze the evolution of search intensity for a selection of digital educational resources over the period 2015 to 2021. Special attention is paid to the period of COVID-19 pandemic, namely, March 2020 to June 2021. The findings include a widespread rise in the use of digital resources with respect to the use in the last 5 years, which varies by digital educational resource and region. However, the use of digital resources in Spain does not seem to vary according to family income, at least in relation to open access digital educational resources. In addition, there appears to be a steady decline in search intensity for digital educational resources and a certain degree of substitutability following the surge due to the pandemic and the school closures.

No abstract

La creación por la Unión Europea de la Red Natura 2000 ha obligado a las administraciones a cambiar las normas ambientales sobre los recursos disponibles, como zonas agrícolas, con el fin de permitir la sostenibilidad del medio ambiente y las actividades económicas preexistentes. En este trabajo se emplean modelos hedónicos y Sistemas de Información Geográf ica para evaluar económicamente las características de estos territorios con respecto a sus principales atributos. Aplicamos esta combinación de métodos a la Zona de Especial Protección para lasAves número (ZEPA) 56 para la Comunidad de Madrid en España, que se encuentra alrededor de los ríos Alberche y Cof io y que formaría parte de la denominada Red Natura 2000 de la Unión Europea. Posteriormente se determinan los aspectos más relevantes para las parcelas de terreno dentro del área protegida, como la calidad del suelo, la distancia a la red de carreteras, etc., y el efecto sobre su precio. Los resultados muestran que aquellas características que hacen que la tierra sea más versátil aumentan su valor, mientras que aquellos que puedan condicionar su uso agrícola o alternativa, como fauna protegida, lo reducen.

No abstract