Mapping and Analysis of Geodiversity Indices in the Xingu River Basin, Amazonia, Brazil

Abstract

From the 1990s, geodiversity studies have been widely carried out in order to understand, describe and preserve the natural heritage of the abiotic environment. Geodiversity assessments have principally been conducted using geological (minerals, rocks and fossils), geomorphological (landforms and processes) and pedological variables. This concept has been widespread and consolidated in scientific circles, where early studies focused on methods that assessed the spatial variability of the geodiversity, with a particular focus on quantitative aspects. In this study, a geodiversity quantification methodology (Pereira et al. 2013) has been applied to the Xingu River basin (Amazônia, Brazil), which covers approximately 51 million hectares. This methodology is based on measuring and integrating abiotic elements, which are spatialised using thematic maps at scales varying between 1:250,000 and 1:1,000,000 and using a 1:25,000 systematic linkage grid. This methodology was adapted for the Amazonian environment by including parameters related to river channel patterns, as approximately 12.6 % of the area is a fluvial environment (channels and floodplains). After applying the methodology, geodiversity indices varying between 4 and 32 were obtained, and a geodiversity hot spot in the basin was identified in the region known as "Volta Grande do Xingu" (The Great Bend of the Xingu). The results of the study highlight the fragility of legal tools for environmental protection of the area, primarily those related to aspects of the physical environment. Although large portions of the basin are partially or fully protected (as indigenous lands and conservation units), the area with the greatest geodiversity is precisely the one which has fewer legal protection devices and is where the Belo Monte hydroelectric power plant is being built.

Inventory and Quantitative Assessment of Geosites and Geodiversity Sites: a Review

“…The main aim of this paper is to conduct a review and present a systematic approach to inventory and quantification methods applied to geological heritage and geodiversity sites, under the scope of geoconservation strategies. The procedures for the assessment of geodiversity as a whole, independently of the value of the different elements, is another research domain that has recently been under development by several researchers (for instance, Serrano et al 2009;Pellitero et al 2011Pellitero et al , 2014Hjort and Luoto 2012;Pereira et al 2013;Silva et al 2014) but it is out of scope of this paper.…”

Kernel Density Applied to the Quantitative Assessment of Geodiversity

“…The assessment of geodiversity is a recent issue concerning the evaluation of natural diversity. While the first attempts to quantify geodiversity were mainly limited to topographical/ relief features (Xavier-da- Silva et al 2001;Serrano and Flaño 2007;Benito-Calvo et al 2009;Zwolinski 2009;Hjort and Luoto 2010;Muller 2011;Manosso 2012;Pellitero 2012), other approaches tried to considerer all types of geodiversity elements (Carcavilla et al 2007;Forte 2014;Silva et al 2015). More recently, other authors made new approaches to geodiversity assessment (Argyriou et al 2016;Manosso and Nóbrega 2016;Najwer et al 2016;Kaskela and Kotilainen 2017;Stepisnik and Trenchovska 2017).…”

Exploring Hawaiian long-term insular geodiversity dynamics

“…Broadly, geodiversity and its quantification have their roots in geoconservation and scientific applications (Gray 2013, Zwoliński et al 2017, with a focus on geoheritage and geotourism (Zwoliński and Stachowiak 2012, Knight et al 2015, Newsome andDowling 2017), nature conservation (Burek andProsser 2008, Pellitero et al 2011), and land management (Pereira et al 2013, Seijmonsbergen et al 2014, Pellitero et al 2015, Silva et al 2015, Najwer et al 2016, Araujo and Pereira 2017. More recently, (com-ponents of) geodiversity have been used to explain the distribution of biodiversity resulting from landscape patterns (Hjort et al 2015, Bailey et al 2017.…”