Indoor and outdoor atmospheric corrosion monitoring of cultural heritage assets

The conservation state of Cultural Heritage (artefacts stored in museums, historical buildings, etc.) can be severely affected by the environmental conditions which they are exposed to. For this reason, a proper monitoring system is typically required in such locations in order to detect potentially unsafe conditions and to monitor the main atmospheric parameters as temperature and relative humidity, and/or the presence of aggressive gases. In this paper a wireless sensors network, designed and developed at Politecnico di Torino, has been employed for two long-lasting monitoring campaigns in Colombia. The architecture has been deployed both inside museums and outside on historical sites proving its capabilities. The solution is composed of small sensing nodes with volume lower than 8 cm3 and dimensions of 2.5x1.5 cm, which are capable of acquiring temperature and relative humidity for a time in excess of three years. The nodes are battery operated and communicate wireless to small Arduino-based concentrators connected to the Internet and to a cloud storage. Data from all the nodes are made available on the curator’s smart phones in real time, so that the entire site can be monitored from everywhere. The nodes have the capability of locally storing all the measurements for quality assurance and if either the internet connection is not available or the power supply is missing, the proposed system has the possibility of off-line manually uploading data to the cloud after having transferred them from the nodes to a battery-operated receiver. The monitoring campaigns, still in progress, are carried out in two historical sites: the National Museum of Colombia in Bogotà and the historical site of the Puente di Boyacá in Tunja

Cryptic Diversity of African Tigerfish (Genus Hydrocynus) Reveals Palaeogeographic Signatures of Linked Neogene Geotectonic Events

The geobiotic history of landscapes can exhibit controls by tectonics over biotic evolution. This causal relationship positions ecologically specialized species as biotic indicators to decipher details of landscape evolution. Phylogeographic statistics that reconstruct spatio-temporal details of evolutionary histories of aquatic species, including fishes, can reveal key events of drainage evolution, notably where geochronological resolution is insufficient. Where geochronological resolution is insufficient, phylogeographic statistics that reconstruct spatio-temporal details of evolutionary histories of aquatic species, notably fishes, can reveal key events of drainage evolution. This study evaluates paleo-environmental causes of mitochondrial DNA (mtDNA) based phylogeographic records of tigerfishes, genus Hydrocynus, in order to reconstruct their evolutionary history in relation to landscape evolution across Africa. Strong geographical structuring in a cytochrome b (cyt-b) gene phylogeny confirms the established morphological diversity of Hydrocynus and reveals the existence of five previously unknown lineages, with Hydrocynus tanzaniae sister to a clade comprising three previously unknown lineages (Groups B, C and D) and H. vittatus. The dated phylogeny constrains the principal cladogenic events that have structured Hydrocynus diversity from the late Miocene to the Plio-Pleistocene (ca. 0–16 Ma). Phylogeographic tests reveal that the diversity and distribution of Hydrocynus reflects a complex history of vicariance and dispersals, whereby range expansions in particular species testify to changes to drainage basins. Principal divergence events in Hydrocynus have interfaced closely with evolving drainage systems across tropical Africa. Tigerfish evolution is attributed to dominant control by pulses of geotectonism across the African plate. Phylogenetic relationships and divergence estimates among the ten mtDNA lineages illustrates where and when local tectonic events modified Africa's Neogene drainage. Haplotypes shared amongst extant Hydrocynus populations across northern Africa testify to recent dispersals that were facilitated by late Neogene connections across the Nilo-Sahelian drainage. These events in tigerfish evolution concur broadly with available geological evidence and reveal prominent control by the African Rift System, evident in the formative events archived in phylogeographic records of tigerfish

Environmental monitoring in the cultural heritage field

Environmental conditions significantly affect the conservation state of the cultural heritage arte- facts. Temperature and relative humidity are directly related to the degradation of multimateric artefacts both stored in indoor sites and exposed to outdoor conditions. Furthermore, the presence of aggressive gases in the atmosphere can have harmful effects on the long-lasting preservation of cultural heritage as- sets. Therefore, an effective and flexible environmental monitoring system is often required in order to assess if the environmental conditions are suitable for the proper conservation of the artefacts or if some specific action has to be taken for their safeguard. However, several constraints are involved in the design and deployment of environmental monitoring systems to be installed in cultural heritage sites, such as reliability of the system and data quality, operative life, real-time operation, maintenance cost, sensor size and communication range. The proposed monitoring system has been specifically developed for the cultural heritage field trying to achieve a good trade-off among all of these constraints. Nevertheless, its characteristics and flexibility make it suitable for many other applications. The proposed system has been employed in several monitoring campaigns in Italy and abroad. As an example of its application, data acquired during a campaign held in Colombia, are reported in the paper

Influence of vegetation in urban noise levels

El objetivo del estudio fue evaluar la capacidad de la vegetación para mitigar el ruido en el valle de Aburrá. La metodología comprendió dos fases: la primera consistió en la revisión de información secundaria relacionada con dicha función de la vegetación, lo que permitió obtener las bases conceptuales para el posterior desarrollo experimental. En la segunda fase se realizó la medición de los niveles de ruido a 10 m de la fuente sonora (vía de alto tráfico vehicular) en zonas verdes públicas urbanas con diferentes coberturas vegetales (arbórea, arbustiva y arbórea-arbustiva) y sin vegetación. Los resultados no arrojaron diferencias significativas entres los sitios con vegetación y sin ella, lo que permite inferir que en las condiciones del estudio, caracterizadas por contar con unos pocos individuos arbóreos o arbustivos dispersos y poco densos, la vegetación no cumple un papel significativo en la disminución del ruido. Por lo tanto, para su control en zonas urbanas deben tomarse medidas diferentes a la plantación de árboles, o establecer barreras vivas más anchas, largas, altas y densas.The objective of the study was to assess the capacity of vegetation to reduce the noise in the Aburrá valley. The methodology comprised two phases: the first was the revision of secondary information related to the role of vegetation and to obtain the conceptual bases for further experimental development. The second phase was the measurement of noise levels 10 m from the sound source (high traffic road) in urban public green zones with different plant coverage (tree, shrub, and a mixture of trees and shrubs) and without vegetation. Results showed no significant differences between the sites with and without vegetation, allowing us to infer that under conditions of the study, characterized by having few individuals of trees and shrubs dispersed, the vegetation does not play a significant role in reducing noise. Therefore, for its control in urban areas measures other than the planting of trees must be taken, or wider, longer, denser, and higher live barriers should be established

Naturaleza urbana. Plataforma de experiencias

Naturaleza Urbana presenta experiencias autogestionadas que, con el tiempo, se han posicionado como ejercicios alternativos de identificación, monitoreo y recuperación de la biodiversidad urbana. En otros casos, el modelo comunidad-gobierno ha permitido desarrollar diagnósticos y propuestas de gestión corresponsables y sistémicas, entendiendo por esto último iniciativas que nacen desde los valores mismos que cada comunidad le atribuye a su biodiversidad. Del mismo modo, se presentan esfuerzos gubernamentales que han enriquecido la visión ambiental de los principales instrumentos de planificación urbana, por ejemplo, integrando la condición propiamente urbana como oportunidad para aumentar la oferta ambiental de la ciudad, fortaleciendo las funciones y procesos de la biodiversidad y revitalizando, con ello, la calidad de vida del entorno urbano. Por su parte, las universidades y los centros de investigación se han sumado a la ola emergente de generación de conocimiento en biodiversidad urbana (fenómeno nacional e internacional), han brindado evidencia científica de su valor para el bienestar humano y han propuesto reflexiones y lineamientos cualitativos de biodiversidad, con miras a hacer del ordenamiento un ejercicio más coherente con cada contexto territorial en particular.Bogotá, D. C., ColombiaInstituto de Investigación de Recursos Biológicos Alexander von Humbold

Urban Nature

Preservation, restoration, monitoring of biodiversity and promotion of native species, in their strict and classical sense, could be unviable strategies in the cities. Management systems such as the protected areas acquire profoundly different connotations and objectives from the traditional ones when thought of in the context of a city. Similarly, although ecological restoration seeks to return to a baseline ecosystem, there is little that we know about the vegetation present on the urban borders of the main Colombian cities prior to the 20th century. Finally, the models for potential distribution of species could produce unreliable results, because their methodological bases were not conceived based on urban dynamics. In this context, to de ne urban biodiversity and what strategy must be applied for its conservation implies a challenge that, beyond being scienti c, is necessarily social and cultural and involves planning and design. Innovation is inevitable.Bogotá, D. C