Spatial analysis and heritage conservation. Leveraging 3-D data and GIS for monitoring earthen architecture

This paper discusses new advances in heritage site monitoring using a geo-spatial method for assessing the state of preservation of earthen architecture overtime as a preventive conservation measure. The proposed method leverages a comprehensive (quantitative–qualitative) approach that gathers multi-temporal data including environmental information collected by means of environmental loggers, qualitative vulnerability assessment of mud-brick walls, and surface change detection information obtained by comparing terrestrial laser scanning point cloud capturing the decay of building's wall features over time. Producing a detailed spatial understanding of the conservation issues that affect mud-brick walls in large earthen sites, this method can be used by conservators to rapidly identify which buildings require immediate intervention and lay the basis for future evaluation of the conservation actions undertaken. To test the effectiveness of the proposed geospatial model in producing a comprehensive view of the environmental risk and pattern of decay that affect mudbrick structures, this paper presents analyses and results obtained in a six-year study at Çatalhöyük, Turkey. Our results corroborate the effectiveness of the proposed method and prove that it can be successfully employed to create preventive conservation measures at other earthen sites inside and outside the Near East

Intra-site Digital Documentation of the Ancient Maya city of Palenque, Mexico

Since archaeological and historical sites occur in relatively restricted areas, they are non-renewable resources, and like natural resources, are sensitive to human and natural intervention and should be cared for, curated, and preserved for local, national, and international communities. Unfortunately, over the last two decades, climate change, growing political instability, and looting have led to the deterioration of numerous Mesoamerican archaeological sites. In this scenario, digital documentation and remote sensing technologies become invaluable resources to record, monitor, and preserve the diverse Maya cultural heritage of the Southern Mexican state of Chiapas. Current efforts in digitizing and mapping archaeological sites in Mesoamerica mostly use an inter-site approach that leverages airborne Light Detection and Ranging (LiDAR). Nonetheless, the high cost of commercial LiDAR and its current limits in capturing excavated vertical structures urged us to explore alternative approaches to digital documentation able to inform site monitoring and physical conservation and to develop multimodal 3-D survey workflows that can be adopted throughout Mesoamerica. This paper thus presents the preliminary results of our intra-site digital documentation work at the World Heritage site of Palenque, Mexico. It also discusses the potential of integrating intra-site and inter-site digital documentation technologies, such as Unmanned Aerial Systems, image-based modeling, terrestrial laser scanning, and drone-based airborne LiDAR with ground truthing and physical conservation interventions to foster built heritage interpretation, conservation, and preservation in Mexico and in other countries with a high concentration of heritage sites but limited research funding

Distribuição horizontal da macrofauna bentônica na praia do Cassino, extremo sul do Brasil

A distribuição horizontal da macrofauna bentônica na praia do Cassino, Rio Grande do Sul, Brasil foi estudada durante o período de um ano (junho 2004 a maio de 2005) com base em coletas mensais. Foram escolhidos três locais, com 50 m de distância um do outro, sendo que em cada local foram fundeadas três transversais 2 m equidistantes. Cada transversal estendeu-se da base das dunas primárias até aproximadamente 1 m de profundidade no infralitoral. A distância dos níveis de coleta em cada transversal foi de 20 m até o limite superior da zona de varrido, a partir do qual a distância foi de 10 m. Em algumas ocasiões foi evidenciada variação espacial horizontal de alguns dos principais táxons, bem como da comunidade bentônica dentro de uma escala de 50 m e 100 m. Esta variação foi provavelmente reflexo da ação das marés meteorológicas que causam abrupta elevação do nível do mar