Rarity

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Armando Caldeira-pires - One of the best experts on this subject based on the ideXlab platform.

  • Destruction mitigation of thermodynamic Rarity by metal recycling
    Ecological Indicators, 2020
    Co-Authors: Daniel Seabra, Armando Caldeira-pires
    Abstract:

    Abstract Thermodynamic Rarity is defined as the exergy needed to take a mineral from the dispersed state in the earth's crust —the thanatia state — and transform it into a commodity using the prevailing technologies. This study develops a method to evaluate the destruction mitigation of thermodynamic Rarity by metal recycling processes. The thermodynamic Rarity of gold, palladium, silver, and copper was measured. Next, we evaluated the thermodynamic Rarity of a printed circuit board (PCB), in which the palladium, gold, and silver that are recycled in the PCB — and that are critical from the perspective of thermodynamics — represent approximately 0.12% of the weight and approximately 91% of the thermodynamic Rarity. Finally, we evaluated the destruction mitigation of thermodynamic Rarity accomplished by the process of recycling the above four metals in the PCB, calculated as approximately 99%. The energy needed to recycle the four metals of interest in the PCB was approximately 5% of the energy needed for the primary production.

  • The thermodynamic Rarity concept: A systematic review
    Ecological Indicators, 2020
    Co-Authors: Daniel Seabra, Armando Caldeira-pires
    Abstract:

    Abstract The concept of thermodynamic Rarity allows the assessment of the exergy needed to extract metals from common ores considering that mineral reserves have a significant exergy value. Estimates show that the reserves of some rare minerals may be exhausted in the next decades; this will cause a severe abiotic depletion that will make the production of certain commodities unfeasible and result in supply risks. This work presents the main scientific contributions to the evolution of the thermodynamic Rarity concept, which began with the application of exergy analysis to the environmental-economic characterization of the minerals industry. The methodology used in this work is a longitudinal systematic review, considering the “research thematic area” and its subdomains. The search was performed in two large databases of scientific documents, Scopus and Web of Science. The results present the quantitative evolution of the main publications as well as a bibliometric analysis and a qualitative characterization of the contents of the main articles. The main period of this review was from 1983 to 2018, and it included 630 publications. The three main sets of keywords detected were a) “theory-of-exergetic-cost”; b) “exergy-replacement-cost”; and c) “thermodynamic-Rarity”. The concepts that evolved to the idea of thermodynamic Rarity during the period analyzed in the study are a) the theory of the Exergy Cost, suggested in 1986; b) the Concentration Exergy of minerals, elaborated in 2008; c) the Concentration Exergy Cost, of 2008; d) Thanatia, developed between 2008 and 2013; and lastly, e) the Exergy Replacement Cost (ERC), developed between 2008 and 2013, which represents the exergy needed to concentrate a mineral from the Thanatia state to the average concentration in a mine (mine state). The concept of Thermodynamic Rarity was published in a book in 2014 and in an article in 2015. It consists of the ERC plus the exergy needed to convert ore from the mine into a commodity. The thermodynamic Rarity concept was used in 2017 in the proposition of the “Thermodynamic Criticality” and in 2018 as a method to assess the monetary losses caused by the inability to recover metals used in small amounts in vehicle recycling. In addition, in 2018 thermodynamic Rarity was used to suggest specific recommendations in ecodesing.

Fernando Roberto Martins - One of the best experts on this subject based on the ideXlab platform.

  • Forms of Rarity of tree species in the southern Brazilian Atlantic rainforest
    Biodiversity and Conservation, 2010
    Co-Authors: Alessandra Nasser Caiafa, Fernando Roberto Martins
    Abstract:

    The assessment of species Rarity considers local abundance (scarce or abundant population), habitat affinity (stenoecious or euryecious species), and geographic distribution (stenotopic or eurytopic species). When analyzed together these variables classify species into eight categories, from common species to those having small populations, unique habitats, and restricted geographic distribution (form 7), as proposed by Rabinowitz in 1981. Based on these categories, it is possible to calculate the frequency of the different forms of Rarity of the species present in a given site. The Brazilian Atlantic rainforest is considered a hotspot of the world biodiversity harboring many endemic species, which have restricted geographic distribution. Our objective was to identify the forms of Rarity of tree species and their proportions in the southern portion of the Brazilian Atlantic rainforest using Rabinowitz’s forms of Rarity. All the seven forms of Rarity are present in the 846 tree species we analyzed: 46% eurytopic and 54% stenotopic, 73% euryecious and 27% stenoecious, 76% locally abundant and 24% locally scarce species. Eurytopic, euryecious locally abundant species accounted for 41.1%, whereas 58.9% were somehow rare: 4.5% eurytopic, euryecious locally scarce, 0.2% eurytopic, stenoecious locally abundant, 0.1% eurytopic, stenoecious locally scarce, 19.5% stenotopic, euryecious locally abundant, 8.0% stenotopic, euryecious locally scarce, 15.6% stenotopic, stenoecious locally abundant, and 11.0% stenotopic, stenoecious locally scarce. Considering that the most restrictive forms of Rarity precedes extinction, the application of Rabinowitz’s system demonstrated that most tree species of the southern Brazilian Atlantic rainforest are threatened due to their restricted geographic distribution, restriction to a single habitat, reduced local abundance, or even to a combination of these variables.

Mark W. Schwartz - One of the best experts on this subject based on the ideXlab platform.

  • Patterns of Rarity and taxonomic group size in plants
    Biological Conservation, 2005
    Co-Authors: Felipe Domínguez Lozano, Mark W. Schwartz
    Abstract:

    Abstract The objective of this research is to examine the extent to which phylogenetic and geographical drivers of Rarity may interact to help us better predict distributions of rare taxa. This information is useful to conservation biologists when considering plans for the effective capture of biological diversity within reserve systems. We use 33 floras, distributed globally among five biomes, to assess pattern of Rarity across taxonomic group size for plants. We show that small plant families (1–10 taxa) contain consistently fewer rare taxa than expected, while rare plants are proportionately over-represented in large plant families (>100 taxa). We also examine the distribution of species within families. The degree to which species are inequitably distributed among families varied systematically across floristic biomes. Mediterranean floras, in particular, are characterized by a greater than expected fraction of their species pool concentrated within large families, suggesting a high propensity for Rarity simply by virtue of having a higher proportion of their constituent taxa within groups with a high likelihood of Rarity. Finally, an analysis of a suite of floras using a common system of identifying Rarity shows that the fraction of species within floras that are rare is predicted both by flora size and by a general metric (the Gini coefficient) of inequality among family sizes. Together, these patterns suggest a high degree of predictability in the distribution of Rarity in plants that may reflect underlying natural speciation and extinction processes.

  • Taxon size predicts rates of Rarity in vascular plants
    Ecology Letters, 2001
    Co-Authors: Mark W. Schwartz, Simberloff
    Abstract:

    We surveyed Rarity in the vascular plants of the continental U.S.A. and Canada and the vascular plants of Hawaii to test the hypothesis that rates of Rarity are independent of taxonomic group size. We demonstrated that taxonomic groups of plants with few species consistently contained fewer than the expected numbers of rare species. This pattern was apparent at the levels of genus, family, order and class. We also found that the pattern remained when we examined rates of Rarity by comparing sister taxa that share a common ancestor. This pattern may arise from either differential speciation and extinction patterns or taxonomic bias in species designations (lumping and splitting). The pattern of lineages with few species demonstrating reduced rates of Rarity is opposite to that previously observed in mammals and birds. If the protection of representatives from a diversity of lineages is a conservation objective, plant conservation is facilitated by the fact that relatively few species-poor lineages contain rare species.

Daniel Seabra - One of the best experts on this subject based on the ideXlab platform.

  • Destruction mitigation of thermodynamic Rarity by metal recycling
    Ecological Indicators, 2020
    Co-Authors: Daniel Seabra, Armando Caldeira-pires
    Abstract:

    Abstract Thermodynamic Rarity is defined as the exergy needed to take a mineral from the dispersed state in the earth's crust —the thanatia state — and transform it into a commodity using the prevailing technologies. This study develops a method to evaluate the destruction mitigation of thermodynamic Rarity by metal recycling processes. The thermodynamic Rarity of gold, palladium, silver, and copper was measured. Next, we evaluated the thermodynamic Rarity of a printed circuit board (PCB), in which the palladium, gold, and silver that are recycled in the PCB — and that are critical from the perspective of thermodynamics — represent approximately 0.12% of the weight and approximately 91% of the thermodynamic Rarity. Finally, we evaluated the destruction mitigation of thermodynamic Rarity accomplished by the process of recycling the above four metals in the PCB, calculated as approximately 99%. The energy needed to recycle the four metals of interest in the PCB was approximately 5% of the energy needed for the primary production.

  • The thermodynamic Rarity concept: A systematic review
    Ecological Indicators, 2020
    Co-Authors: Daniel Seabra, Armando Caldeira-pires
    Abstract:

    Abstract The concept of thermodynamic Rarity allows the assessment of the exergy needed to extract metals from common ores considering that mineral reserves have a significant exergy value. Estimates show that the reserves of some rare minerals may be exhausted in the next decades; this will cause a severe abiotic depletion that will make the production of certain commodities unfeasible and result in supply risks. This work presents the main scientific contributions to the evolution of the thermodynamic Rarity concept, which began with the application of exergy analysis to the environmental-economic characterization of the minerals industry. The methodology used in this work is a longitudinal systematic review, considering the “research thematic area” and its subdomains. The search was performed in two large databases of scientific documents, Scopus and Web of Science. The results present the quantitative evolution of the main publications as well as a bibliometric analysis and a qualitative characterization of the contents of the main articles. The main period of this review was from 1983 to 2018, and it included 630 publications. The three main sets of keywords detected were a) “theory-of-exergetic-cost”; b) “exergy-replacement-cost”; and c) “thermodynamic-Rarity”. The concepts that evolved to the idea of thermodynamic Rarity during the period analyzed in the study are a) the theory of the Exergy Cost, suggested in 1986; b) the Concentration Exergy of minerals, elaborated in 2008; c) the Concentration Exergy Cost, of 2008; d) Thanatia, developed between 2008 and 2013; and lastly, e) the Exergy Replacement Cost (ERC), developed between 2008 and 2013, which represents the exergy needed to concentrate a mineral from the Thanatia state to the average concentration in a mine (mine state). The concept of Thermodynamic Rarity was published in a book in 2014 and in an article in 2015. It consists of the ERC plus the exergy needed to convert ore from the mine into a commodity. The thermodynamic Rarity concept was used in 2017 in the proposition of the “Thermodynamic Criticality” and in 2018 as a method to assess the monetary losses caused by the inability to recover metals used in small amounts in vehicle recycling. In addition, in 2018 thermodynamic Rarity was used to suggest specific recommendations in ecodesing.

Alessandra Nasser Caiafa - One of the best experts on this subject based on the ideXlab platform.

  • Forms of Rarity of tree species in the southern Brazilian Atlantic rainforest
    Biodiversity and Conservation, 2010
    Co-Authors: Alessandra Nasser Caiafa, Fernando Roberto Martins
    Abstract:

    The assessment of species Rarity considers local abundance (scarce or abundant population), habitat affinity (stenoecious or euryecious species), and geographic distribution (stenotopic or eurytopic species). When analyzed together these variables classify species into eight categories, from common species to those having small populations, unique habitats, and restricted geographic distribution (form 7), as proposed by Rabinowitz in 1981. Based on these categories, it is possible to calculate the frequency of the different forms of Rarity of the species present in a given site. The Brazilian Atlantic rainforest is considered a hotspot of the world biodiversity harboring many endemic species, which have restricted geographic distribution. Our objective was to identify the forms of Rarity of tree species and their proportions in the southern portion of the Brazilian Atlantic rainforest using Rabinowitz’s forms of Rarity. All the seven forms of Rarity are present in the 846 tree species we analyzed: 46% eurytopic and 54% stenotopic, 73% euryecious and 27% stenoecious, 76% locally abundant and 24% locally scarce species. Eurytopic, euryecious locally abundant species accounted for 41.1%, whereas 58.9% were somehow rare: 4.5% eurytopic, euryecious locally scarce, 0.2% eurytopic, stenoecious locally abundant, 0.1% eurytopic, stenoecious locally scarce, 19.5% stenotopic, euryecious locally abundant, 8.0% stenotopic, euryecious locally scarce, 15.6% stenotopic, stenoecious locally abundant, and 11.0% stenotopic, stenoecious locally scarce. Considering that the most restrictive forms of Rarity precedes extinction, the application of Rabinowitz’s system demonstrated that most tree species of the southern Brazilian Atlantic rainforest are threatened due to their restricted geographic distribution, restriction to a single habitat, reduced local abundance, or even to a combination of these variables.