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Canga, or ironstone, ecosystems are hotspots of old-growth plant diversity and highly specialized cave invertebrates. These ancient metalliferous habitats are amongst the most threatened ecosystems because of the destruction caused by large-scale iron ore mining. International debate on biodiversity offsets is increasing because these mechanisms are seen as tools for potentially balancing economic development with conservation biodiversity. Leading mining companies worldwide, including some of the largest iron ore producers in Brazil, are signatories to offset principles and best practices that aim to achieve no net loss of habitats, species or ecosystem functions. We aimed to analyse whether Brazilian legal requirements for biodiversity offsets result in the achievement of conservation outcomes or in elevated threat of extinction in canga ecosystems. We evaluated technical reports that support decision-making related to environmental licensing for iron ore mining and specific offset proposals linked to the Atlantic Forest Act. We found a relevant net loss in canga ecosystems and observed shortcomings related to the equivalency and transparency of offset principles. These deficiencies are mainly related to lax norms and regulations and the absence of an integrated database for accessing information on environmental licensing processes. We argue that both policy flaws and low engagement by the Brazilian mining industry in implementing offset principles have increased the threat of extinction in canga ecosystems.

A recent state provision allows quarzitic campo rupestre (QCR) set-asides as in-kind compensation for ironstone campo rupestre (ICR) suppression in the Atlantic Forest, which induces out-of-kind compensation. However, the recently published state provision defines no clear parameters to demonstrate “ecological equivalence” as an in-kind compensation. We evaluated whether there is ecological equivalence between and ICR and QCR in the Brazilian Atlantic Forest. We show marked geological, pedological, floristic, structural, and functional differences between ICR and QCR. There is evidence that the new compensation rules only partially offset loss of biodiversity and ecosystem services hosted by ICR, determining limited effectiveness of the legislation for ICR conservation in the Atlantic Forest. We conclude that the development of clear compensation parameters based on scientific evidence and quantitative indicators is a priority gap for the conservation of ICR under increasing mining pressure.

Insufficient knowledge about ecology of weed macrophytes from a large-scale perspective narrows the necessary decision-making for biodiversity conservation. The present study aimed to assess the occurrence frequency of Egeria densa in lotic and lentic/semi-lotic environments from a Brazilian dammed river, as well as to quantify the attributed explanation (pure or combined) by limnological and spatial variables on species occurrence frequency. Between 2006 and 2010, we repeatedly visited sample points classified as lotic (45) or lentic/semi-lotic environments (23) to collect data on species occurrence and limnological variables. We also generated spatial variables derived from latitude and longitude of sample points. E. densa showed a recurrent occurrence in the sample points classified as lentic/semi-lotic. Both spatial variables (16) and limnological variables (total phosphorus, nitrate, nitrite, transparency and turbidity) significantly contributed to explaining the species occurrence frequency. Forty-nine percent of the occurrence frequency variation was accounted purely by spatial variables. However, less than five percent of occurrence frequency variation was accounted purely by limnological variables. The several dams placed along the river determined the lentic/semi-lotic environments formation and regulated the dispersion processes of individuals of E. densa, consequently causing a recurrent occurrence of this species in particular environmental classes.

Irreversible losses of natural areas and damage to ecosystem services are caused by large-scale mining. These effects are prominent in Minas Gerais, which is home to a mining industry with hundreds of tailings dams concentrated in global hotspots: the Cerrado and the Atlantic Forest. We present an overview of the spatial overlap between protected areas (PAs), priority conservation areas (PCAs), tailings dams, and their influence areas. A total of 218 dams accumulated environmental costs and liability that are represented by 2.24 thousand million m(3) of tailings and industrial waste. Most dams (≈ 70%) are located in PCAs, 45 dams in conservation units, 58 in their respective buffer zones, and 51 in special protection areas. We have identified an urgent need to implement adequate public policies to establish management and monitoring mechanisms in PAs and PCAs and to address a scenario of high potential for socioenvironmental damage associated with tailings dams.

The Iron Quadrangle (IQ) is one of the main iron ore producing regions of the world. The exploitation of its reserves jeopardizes the high biological endemism associated with this region. This work aimed to understand the diversity and bacterial potential associated with IQ caves. Floor and ceiling samples of seven ferruginous caves and one quartzite cave were collected, and their microbial relative abundance and diversity were established by 16S rRNA gene amplicon sequencing data. The results showed that ferruginous caves present higher microbial abundance and greater microbial diversity compared to the quartzite cave. Many species belonging to genera found in these caves, such as Pseudonocardia and Streptacidiphilus, are known to produce biomolecules of biotechnological interest as macrolides and polyketides. Moreover, comparative analysis of microbial diversity and metabolic potential in a biofilm in pendant microfeature revealed that the microbiota associated with this structure is more similar to the floor rather than ceiling samples, with the presence of genera that may participate in the genesis of these cavities, for instance, Ferrovum, Geobacter, and Sideroxydans. These results provide the first glimpse of the microbial life in these environments and emphasize the need of conservation programs for these areas, which are under intense anthropogenic exploration.

Digital, Biocontrol and plant growth-promoting bacteria (PGPB) are important agricultural bioinoculants. This study aimed to prospect new potential bioinoculants for a more sustainable agriculture from ferruginous caves of the Brazilian Iron Quadrangle. Culturable bacteria, from seven caves and one canga soil sample, were evaluated for biocontroller activity of the phytopathogens Xanthomonas citri subsp. Citri—Xcc306 (citrus canker), Fusarium oxysporum—Fo (fusariosis), and Colletotrichum lindemuthianum—Cl89 (bean anthracnose). The ability of the superior candidates to solubilize inorganic phosphate, fix nitrogen, and produce hydrolytic enzymes and siderophores was then analyzed. Out of 563 isolates, 47 inhibited the growth of Xcc306 in vitro, of which 9 reduced citrus canker up to 68% when co-inoculated with the pathogen on host plants. Twenty of the 47 inhibited Fo growth directly by 51–73%, and 15 indirectly by 75–81%. These 15 inhibited Cl89 growth in vitro (up to 93% directly and 100% indirectly), fixed nitrogen, produced proteases and siderophores, showed motility ability, produced biofilm, and all but one solubilized inorganic phosphate. Therefore, 15 (2.66%) bacterial isolates, from the genera Serratia, Nissabacter, and Dickeya, act simultaneously as biocontrollers and PGPBs, and could be important candidates for future investigations in planta as an alternative to minimize the use of pesticides and chemical fertilizers through sustainable agricultural management practices., Ciencias Exactas y Naturales

Serratia liquefaciens strain FG3 (SlFG3), isolated from the flower of Stachytarpheta glabra in the Brazilian ferruginous fields, has distinctive genomic, adaptive, and biotechnological potential. Herein, using a combination of genomics and molecular approaches, we unlocked the evolution of the adaptive traits acquired by S1FG3, which exhibits the second largest chromosome containing the largest conjugative plasmids described for Serratia. Comparative analysis revealed the presence of 18 genomic islands and 311 unique protein families involved in distinct adaptive features. S1FG3 has a diversified repertoire of genes associated with Nonribosomal peptides (NRPs/PKS), a complete and functional cluster related to cellulose synthesis, and an extensive and functional repertoire of oxidative metabolism genes. In addition, S1FG3 possesses a complete pathway related to protocatecuate and chloroaromatic degradation, and a complete repertoire of genes related to DNA repair and protection that includes mechanisms related to UV light tolerance, redox process resistance, and a laterally acquired capacity to protect DNA using phosphorothioation. These findings summarize that SlFG3 is well-adapted to different biotic and abiotic stress situations imposed by extreme conditions associated with ferruginous fields, unlocking the impact of the lateral gene transfer to adjust the genome for extreme environments, and providing insight into the evolution of prokaryotes. Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brazil (CAPES)CAPES [001, CFP 51/2013, 3385/2013]; National Council of Technological and Scientific Development (CNPq)National Council for Scientific and Technological Development (CNPq) [481226/2013-3]; Foundation of Protection to Research of the State of Minas Gerais - FAPEMIG [APQ-02387-14, APQ-02357-17]; CNPqNational Council for Scientific and Technological Development (CNPq); Fundect-MS [TO 141/2016, TO 007/2015, 007/2015 SIAFEM 025139]; UFOP grants; Laboratory of Biochemistry and Molecular Biology of the Faculty of Agrarian and Veterinary Sciences UNESP, Jaboticabal campus Thanks to all members of the Laboratory of Biochemistry and Molecular Biology (LBBM, Federal University of Ouro Preto, UFOP) and to the Laboratory of Biochemistry and Molecular Biology of the Faculty of Agrarian and Veterinary Sciences UNESP, Jaboticabal campus, for their support. This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brazil (CAPES) - Finance Code 001 - (the BIGA Project, CFP 51/2013, process 3385/2013), National Council of Technological and Scientific Development (CNPq Process 481226/2013-3), and Foundation of Protection to Research of the State of Minas Gerais - FAPEMIG (process APQ-02387-14 and process APQ-02357-17). LMM, JCS, AMV, NFA and JAF have a research fellowship from CNPq. NFA has grants from Fundect-MS (TO 141/2016 and TO 007/2015) and Fundect-MS (007/2015 SIAFEM 025139). LAGM and LMM have UFOP grants. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

The campo rupestre is a Neotropical azonal vegetation. Its disjoint distribution and the fact that it is an old climatic buffered infertile landscape (OCBIL) have been associated with the high diversity and endemism observed in this environment. Here, we tested whether a micro-endemic species from campo rupestre shows: (1) limited zygotic gene flow; (2) lower gametic than zygotic gene flow structure; (3) substrate-driven genetic structure and (4) no evidence of Pleistocene local extinction or recolonization. By sequencing intergenic plastid regions, phenotyping inter simple sequence repeats (ISSR) and modelling present and past species suitability distributions for Vellozia auriculata we conclude that (1) zygotic gene flow is limited; (2) gametic gene flow is recurrent, but limited by elevation and distance; (3) there is no support for genetic structure driven by substrate and (4) Pleistocene climatic changes did not restrict the species to refugia, with local persistence. As long-term gene flow restrictions may lead to differentiation and speciation, our data helps to corroborate that the campo rupestre is both a cradle (due to low zygotic gene flow, prolonged isolation and consequent differentiation) and a lineage museum (due to local survival during climate oscillations). We highlight two distinct evolutionarily significant units (ESU), providing information for better conservation practice.

The management of long-lived mining wastes is a complex environmental challenge, but the subject is little discussed among the public, scientific community, and policymakers. The negative environmental impacts caused by mining wastes are severe and cause damage to human health and the loss and degradation of natural ecosystems. With the objective of stimulating discussion to advance the development of measures to contain threats to biodiversity and to mitigate negative impacts, we present an overview of total volumes of mining waste disposal in tailings dams and dump piles, discriminating them by ore type and biome. We highlight the major environmental risks and challenges associated with tropical forests, savannas, and freshwater ecosystems and possible limitations and advances in public policies and governance. The scale of this challenge is global, as some data show, for example, Brazil generated 3.6 billion tons of solid mining waste in dump piles in the period between 2008 and 2019. The volume is equivalent to 62% of the global mass of nonfuel minerals removed from the planet’s crust in 2006. Numerous socio-environmental disasters are caused by catastrophic mining dam failures, and over the last 34 years, an average of one failure has occurred every three years in Brazil.

This study aims to map the spatial distribution of Atlantic cloud forest and assess its protection status in the Serra da Mantiqueira, southeastern Brazil, using a combination of predictive distribution modelling and remote sensing techniques. The potential distribution of cloud forests in the Serra da Mantiqueira was predicted using a combination of three algorithms for different environmental variables, including climatic, hydrometeorological, a topographic variable and a fog-related variable. After estimating the potential cloud forest distribution, remote sensing mapping techniques were used to approximate actual cloud forest area. Four land-use classes were distinguished: cloud forest, plantation forest, a ‘high-altitude complex’, and ‘other covers’. Actual mapped cloud forest areas were compared with locations of existing protected areas to assess the status of regional cloud forest protection. Predicted cloud forest distribution was excellent, with conditions above 1500 m.a.s.l. generally the most suitable for cloud forest occurrence. Actual cloud forest occurrence mapped with remote sensing imagery was 52% of the predicted potential area with differences likely due to past forest loss and the presence of non-forest (‘high-altitude complex’) vegetation. Much of the mapped cloud forest area is under nominal protection, with most areas falling into the ‘Protected Area with Sustainable Use of Natural Resources’ category. The combined use of predictive distribution modelling and remotely sensed observations successfully mapped cloud forest extent in the study area. The results reinforce the need to assign high conservation priority to the Serra da Mantiqueira as a whole and to create a core area with full protection status.

The ferruginous rupestrian grasslands (FRG) in the Iron Quadrangle (IQ) are ecosystems characterized by rocky soils with reduced availability of water and nutrients, but high levels of metals. In order to comprehend the interference of microorganisms on the adaptive process of endemic plant Mimosa calodendrum (Fabaceae), bacteria associated with its roots and rhizosphere were isolated. Fourteen isolates were obtained and subsequently grown in the presence of different concentrations of arsenic (As) species. The isolate Mc250, an Alcaligenes faecalis strain, resisted to 10 mM of As (III) and 800 mM of As (V). In the presence of this strain, atomic spectrometer detected a reduction of 55% for As (III) and 72% for As (V) respectively in 10 mM and 500 mM solution. Scanning electron microscopy of this isolate demonstrated morphological modification and EDX spectroscopy revealed the presence of both As species adsorbed on the membrane, justifying the removal observed in the in vitro assays. To validate this potential removal of As in vivo, tomato plants were used as grown model in the presence and absence of A. faecalis in soil previously contaminated with 5 mM of As (III). After 14 days, plants from contaminated soil had their growth improved when compared to untreated control plants. All these results suggest for the first time that plant-associated bacteria from FRG-IQ present potential for soil rhizoremediation and may benefit the adaptive processes of plants in extreme environments including application in recovering degraded areas.

Made available in DSpace on 2021-06-25T10:44:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01 Here we present and analyze the complete genome of Alcaligenes faecalis strain Mc250 (Mc250), a bacterium isolated from the roots of Mimosa calodendron, an endemic plant growing in ferruginous rupestrian grasslands in Minas Gerais State, Brazil. The genome has 4,159,911 bp and 3,719 predicted protein-coding genes, in a single chromosome. Comparison of the Mc250 genome with 36 other Alcaligenes faecalis genomes revealed that there is considerable gene content variation among these strains, with the core genome representing only 39% of the protein-coding gene repertoire of Mc250. Mc250 encodes a complete denitrification pathway, a network of pathways associated with phenolic compounds degradation, and genes associated with HCN and siderophores synthesis; we also found a repertoire of genes associated with metal internalization and metabolism, sulfate/sulfonate and cysteine metabolism, oxidative stress and DNA repair. These findings reveal the genomic basis for the adaptation of this bacterium to the harsh environmental conditions from where it was isolated. Gene clusters associated with ectoine, terpene, resorcinol, and emulsan biosynthesis that can confer some competitive advantage were also found. Experimental results showed that Mc250 was able to reduce (∼60%) the virulence phenotype of the plant pathogen Xanthomonas citri subsp. citri when co-inoculated in Citrus sinensis, and was able to eradicate 98% of juveniles and stabilize the hatching rate of eggs to 4% in two species of agricultural nematodes. These results reveal biotechnological potential for the Mc250 strain and warrant its further investigation as a biocontrol and plant growth-promoting bacterium. Núcleo de Pesquisas em Ciências Biológicas (NUPEB) Universidade Federal de Ouro Preto Departamento de Ciências Biológicas (DECBI) Instituto de Ciências Exatas e Biológicas (ICEB) Universidade Federal de Ouro Preto (UFOP) Instituto Pristino Departamento de Bioquimica (DBQ) Instituto de Quimica (IQ) Universidade de São Paulo (USP) Instituto de Biotecnologia Aplicada a Agropecuária (BIOAGRO) Universidade Federal de Vicosa (UFV) Departamento de Tecnologia Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV) Universidade Estadual Paulista (UNESP) Faculdade de Computação (FACOM) Universidade Federal de Mato Grosso do Sul Departamento de Tecnologia Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV) Universidade Estadual Paulista (UNESP)

Atlantic Tropical Brazil is a landscape area located along the coast of the Atlantic Ocean and in the inland sector of Brazil. It is on the South American Platform, and it occupies parts of a craton, three Brazilian orogenic systems, and a large Phanerozoic sedimentary basin. The soils are complexly diverse, with many morphological characteristics and different classes, and pedogenesis that ranges from intense to weak. Most of this area has climates with high relative air humidity and abundant and well-distributed rainfall throughout the year. The combination of moving air masses and topographic relief promotes great humidity in the landscape, with high rainfall rates, underground recharge, and surface discharge, in addition to high water yield and considerable seasonal stability of flow rates. These features support predominantly forested vegetation, known as Atlantic Forest, which shelters a very rich and endemic biological diversity that is threatened; however, more than 70% of its original cover has been destroyed.

Made available in DSpace on 2019-10-06T15:59:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-10-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Microorganisms associated with plants have a great biotechnological potential, but investigations of these microorganisms associated with native plants in peculiar environments has been incipient. The objective of this study was to analyze the plant growth-promoting bacteria potential of cultivable bacteria associated with rare plants from the ferruginous rocky fields of the Brazilian Iron Quadrangle. The roots and rhizospheres of nine endemic plants species and samples of a root found in a lateritiric duricrust (canga) cave were collected, the culturable bacteria isolated and prospected for distinct biotechnological and ecological potentials. Out of the 148 isolates obtained, 8 (5.4%) showed potential to promote plant growth, whereas 4 (2.7%) isolates acted as biocontrol agents against Xanthomonas citri pathotype A (Xac306), reducing the cancrotic lesions by more than 60% when co-inoculated with this phytopathogen in Citrus sinensis plants. Moreover, other 4 (2.7%) isolates were classified as potential bioremediation agents, being able to withstand high concentrations of arsenite (5 mM As3+) and arsenate (800 mM As5+), by removing up to 35% and 15% of this metalloid in solution, respectively. These same four isolates had a positive influence on the growth of both the roots and the aerial parts when inoculated with tomato seeds in the soil contaminated with arsenic. This is the first time that an investigation highlights the potentialities of bacteria associated with rare plants of ferruginous rocky fields as a reservoir of microbiota of biotechnological and ecological interest, highlighting the importance of conservation of this area that is undergoing intense anthropic activity. Graphical abstract: [Figure not available: see fulltext.]. Programa de Pós-graduação em Biotecnologia Núcleo de Pesquisas em Ciências Biológicas Universidade Federal de Ouro Preto Departamento de Ciências Biológicas (DECBI) Instituto de Ciências Exatas e Biológicas (ICEB) Universidade Federal de Ouro Preto (UFOP) Departamento de Tecnologia Universidade Estadual Paulista UNESP, Campus de Jaboticabal Instituto Prístino Departamento de Tecnologia Universidade Estadual Paulista UNESP, Campus de Jaboticabal CAPES: 3385/2013 CNPq: 481226/2013-3 FAPEMIG: APQ-02387-14 CAPES: CFP 51/2013

Ironstone ranges are considered hotspots for higher plants α and β diversity. The lack of studies and the intense degradation of the ironstone ranges, due to mining, motivated us to compile, for the first time, a list of vascular plants collected on iron-rich derived substrates from ancient landscape of south-eastern Brazil. All existing records in the Brazilian Virtual Herbarium of Flora and Fungi for each of the 43 municipalities containing ironstone ranges were downloaded, resulting in 17,954 vouchers identified to the species level. We found 2,933 species belonging to 160 families and 818 genera. For the first time, we identified 148 species mentioned in endangered flora official lists and 48 narrow endemic species. Collecting efforts must still be supported to properly sample the vegetation since, for 143 sites, less than 10 records/site were found. This dataset will assist with the indication of dozens of plant species whose threat criteria must be urgently assessed to subsidise public policies on the use and conservation of the Brazilian flora.

A educação ambiental (EA), enquanto campo epistemológico, pode auxiliar no despertar da compreensão do papel do indivíduo no ambiente. Neste trabalho, apresenta-se o resultado da parceria entre o Mestrado Profissional em Ensino de Ciências da Universidade Federal de Ouro Preto e o Instituto Prístino, com o objetivo de desenvolver uma cartilha de EA, envolvendo o ecossistema de canga, para professores e alunos do ensino fundamental II. Em Minas Gerais, os ecossistemas ferruginosos – conhecidos como “cangas” – apresentam características abióticas que resultaram em um dos ambientes com maior endemismo vegetal do Brasil. Atuando como reserva hídrica que abastece mananciais da região metropolitana de Belo Horizonte, as cangas estão na lista dos ecossistemas mais ameaçados, em especial pela mineração. Este artigo fornece conceitos, peculiaridades, importâncias, ameaças e desafios, além de exercícios de fixação e discussão contextualizada, sendo, portanto, uma ferramenta diferenciada para o ensino de Ciências. Environmental Education (EE), while an epistemological field, may assist to awake the comprehension of individuals’ role within the environment. In this work, we present the result of a partnership between the Professional Masters Studies in Science Teaching from the Federal University of Ouro Preto and the Prístino Institute, aiming to develop an EE textbook involving the canga ecosystem for teachers and students of the basic education. In Minas Gerais, ferruginous ecosystems – known as “Cangas” – present abiotic characteristics that resulted in one of the environments with higher plant endemism in Brazil. Acting as a water reservoir that supplies water sources of the metropolitan region of Belo Horizonte, the Cangas are on the list of the most endangered ecosystems, especially by mining. This article provides concepts, peculiarities, importance, threats and challenges, in addition to fixation exercises and contextualized discussion being, therefore, a differentiated tool for Science teaching.

The Atlantic Forest encompasses a high level of biodiversity, endemism and degradation; hence, it is a biome of particular interest for biological conservation. We aimed to investigate the actual geographic distribution of tree species and, among the indicator species of each vegetation type, the conservation status and potential distribution of each species along a vegetation gradient of the Subtropical Atlantic Forest. We analysed the species’ relative constancy to determine their actual distribution, obtained 21 indicator species of the different vegetation types and modelled their potential distribution using the maximum entropy algorithm. The potential distribution models were pooled to yield a single map, which was used to predict the distribution of climatic suitability for these species in South America. Our results showed that the actual geographic distribution is restricted for most species (~72 %). Araucaria angustifolia and Euterpe edulis were categorized as threatened species. The sum of the indicator-species maps showed reduced climatic suitability across most of South America. The southern region of Brazil and the southeastern Brazilian highlands, as well as a few areas of seasonal forests on higher elevations of the Bolivian Chiquitania and Andean Piedmont, exhibited the best climatic suitability. Elevation was the most important variable in our models. Given the concerning level of forest degradation and the presence of endangered and geographic restricted species, our results are a relevant contribution to biodiversity conservation in the Subtropical Atlantic Forest areas, highlighting their floristic and environmental uniqueness and, therefore, the urgent necessity of preserving their biological heritage.

We combined distribution data of bryophyte species with protected areas in the Brazilian Atlantic Forest, using models of potential distribution of species, in order to assess the effectiveness and representativeness of Conservation Units for bryophyte species. We performed potential distribution models for ten bryophyte species classified as bio-indicators for environmental quality and/or endemic to the Atlantic Forest, or endemic to Brazil (key species). Data from online herbarium collections, literature, and sampling were used to estimate the potential distribution of the species, based on the MAXENT method. We performed an intersection between the maps with > 50% of environmental suitability for the occurrence of the studied species and the maps of the Brazilian protected areas. Areas with the greatest potential presence of bryophyte species not superimposed on protected areas were considered areas of gaps in protection. The habitat suitability of the models for nine species was explained by the Mean Diurnal Temperature Range. The consensus map of high environmental suitability for all species showed significant gaps in knowledge about their distribution. However, three centers of potential distribution were recognizable: one in the Northeast, one Central and another one in the Southeast. The total potentially suitable area overlapped with 83 Conservation Units (only 27%), less than adequate for efficient conservation of the species. The Central Corridor was the region with the highest environmental suitability but also has only a few Conservation Units in the Atlantic Forest, and is therefore a priority for conducting inventories and creating reserves.

Current techniques for estimating the extent of occurrence (EOO) of species, especially those with a naturally disjunct distribution and limited available data, lead to overestimations of their geographic distributions. Accurate EOO estimates are of great importance because they are used to assess conservation status. Topological methods, such as those proposed by the International Union for Conservation of Nature (IUCN), are not able to estimate the geographical distribution of these species accurately because they do not consider the abiotic characteristics suitable to maintain viable populations. In this study, we propose the use of ecological niche models (ENMs) to estimate the EOO. We use the Maximum Entropy (MaxEnt) algorithm and the topological method suggested by IUCN (α-hull method) to estimate the EOO for a species with disjunct distribution and limited available data. The estimate obtained using the ENM was considered the most accurate because only areas with suitable abiotic conditions were taken into account. Thus, analyses related to the conservation status of species become more accurate, especially when evaluating the effects of potential threats in the potential areas occupied by the taxon. The estimate obtained from ENM can also assist the design of conservation strategies for the species, by indicating areas for specific surveys and assessing changes in the EOO over time.

During the Pleistocene a fauna composed of large (biomass > 44 kg) and giant mammals (biomass > 1000 kg) that are usually associated with open environments lived in the Brazilian Intertropical Region. We present here new information concerning the paleoecology and chronology of some species of this megafauna. Carbon isotope analyses were performed for a better understanding of the paleoecology of the species Eremotherium laurillardi (Lund, 1842), Notiomastodon platensis (Ameghino, 1888) and Toxodon platensis (Owen, 1849). The δ13C data allow attributing a generalist diet to these species, which varied according to the kind of habitat in which they lived. In more open habitats all species were grazers; in mixed habitats E. laurillardi and T. platensis were mixed feeders, and N. platensis was grazer; and in more closed habitats all species were mixed feeders.

In order to develop niche models for tree species characteristic of thecerrado vegetation (woody savannas) of central South America, and tohindcast their distributions during the Last Glacial Maximum and Last Inter-Glacial, we compiled a dataset of tree species checklists for typical cerradovegetation (n=282) and other geographically co-occurring vegetationtypes, e.g. seasonally dry tropical forest (n=355). We then performed anIndicator Species Analysis to select ten species that best characterizetypical cerrado vegetation and developed niche models for them using theMaxent algorithm. We used these models to assess the probability ofoccurrence of each species across South America at the following timeslices: Current (0 ka pre-industrial), Holocene (6 ka BP), Last GlacialMaximum (LGM - 21 ka BP), and Last Interglacial (LIG - 130 ka BP). Theniche models were robust for all species and showed the highest probabilityof occurrence in the core area of the Cerrado Domain. The palaeomodelssuggested changes in the distributions of cerrado tree species throughoutthe Quaternary, with expansion during the LIG into the adjacentAmazonian and Atlantic moist forests, as well as connections with otherSouth American savannas. The LGM models suggested a retraction ofcerrado vegetation to inter-tableland depressions and slopes of the CentralBrazilian Highlands. Contrary to previous hypotheses, such as thePleistocene Refuge Theory, we found that the widest expansion of cerradotree species seems to have occurred during the LIG, most probably due toits warmer climate. On the other hand, the postulated retractions duringthe LGM were likely related to both decreased precipitation andtemperature. These results are congruent with palynological andphylogeographic studies in the Cerrado Domain.

The workshop ‘ Species distribution models: applications, challenges and perspectives ’ held at Belo Horizonte (Brazil), 29–30 August 2011, aimed to review the state-of-the-art in species distribution modelling (SDM) in the neotropical realm. It brought together researchers in ecology, evolution, biogeography and conservation, with different backgrounds and research interests. The application of SDM in the megadiverse neotropics—where data on species occurrences are scarce—presents several challenges, involving acknowledging the limitations imposed by data quality, including surveys as an integral part of SDM studies, and designing the analyses in accordance with the question investigated. Specific solutions were discussed, and a code of good practice in SDM studies and related field surveys was drafted.

ISSN 1948-6596 news and update workshop summary The application of species distribution models in the megadi- verse Neotropics poses a renewed set of research questions Species distribution models: applications, challenges and perspectives – Belo Horizonte, Brazil, 29 th –30 th August 2011 The community of researchers and technicians interested in biogeography is large and growing in Brazil, with members coming from fields as di- verse as ecology, evolution and conservation. The increment in the number of postgraduate pro- grams in ecology and evolutionary biology is linked to many research questions about the causes and dynamics of species’ ranges, as well as about their consequences for short-term evolu- tionary processes. As a result, the use (and abuse) of species distribution models (SDMs) as a tool in research and technical studies has grown rapidly in recent years. Systems that integrate biodiver- sity databases (e.g. SpeciesLink 1 ) allow one to ob- tain distributional information about many spe- cies; and easy-to-use SDM software (e.g. MaxEnt 2 , Phillips et al. 2004, or openModeller 3 , Munoz et al. 2011) is also available online. The easy avail- ability of data and SDM tools provides a powerful means for answering questions about the geo- graphic distribution of species. Potential users include non-specialist researchers, untrained post- graduate students and government technicians. But is this helping to develop a sound and solidly grounded knowledge of the distribution of Neotropical diversity? In order to unite the Brazilian community of SDM users and provide them with a better under- standing of the technique, the Postgraduate Course on Plant Biology of the Universidade Fed- eral de Minas Gerais organized a workshop in Belo Horizonte last August. This workshop allowed more than 100 students and technicians to meet and discuss with researchers working with SDMs. The main conclusions of the meeting were that there is a growing interest in using the technique to study species’ distributions and find unknown populations of rare species, and that there is a need for a code of good practice in both field sur- veys and SDM applications. These conclusions have been already discussed elsewhere (Kamino et al. 2011). Here we develop further one of the problems identified during the workshop: the lack of clear questions in many studies using SDMs; in other words, the mere application of species dis- tribution modelling as a fashionable technique often ‘justifies’ a study. Reviews summarizing the most important challenges for SDMs (e.g. Araujo and Guisan 2006, Zimmermann et al. 2010, Peterson et al. 2011) typically present how users view the field and what problems they perceive in each step in the modelling process. However, things move fast in this emerging field of research because, while the number of studies using SDMs increases steadily (see Fig. 1 in Lobo et al. 2010), the technique is also used to address completely new questions. Thus, the challenges to their application are them- selves changing. We believe that the most impor- tant of these challenges are theoretically rather than methodologically grounded, although we recognize that both kinds of problems overlap to some extent. Here we outline the basic questions that we believe SDM users must take into account while studying current species’ distributions. Soberon (2007) provides perhaps the best starting point to understand the theoretical prob- lems of SDMs (see also Colwell and Rangel 2009; Soberon 2010). The first problem is the definition of a clear research question. Here it is important to discriminate between theoretical questions such as “Why is this species here?” – which are more interesting in the long run – from those that are eminently practical such as “Where is this spe‐ cies?” – which unfortunately seem to be the most common. But even practical questions stimulated 1 http://www.splink.org.br; last accessed 10/11/2011 2 http://www.cs.princeton.edu/~schapire/maxent/; last accessed 10/11/2011 3 http://openmodeller.sourceforge.net/; last accessed 10/11/2011 frontiers of biogeography 4.1, 2012 — © 2012 the authors; journal compilation © 2012 The International Biogeography Society

RESUMOKAMINO, L.H.Y. (2009). Modelos de Distribuição Geográfica Potencial: Aplicaçãocom Espécies da Flora Ameaçada de Extinção da Floresta Atlântica. Tese (Doutorado) Instituto Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte.Orientador: João Renato StehmannModelos de distribuição geográfica têm sido utilizados como uma importanteferramenta na biologia da conservação, gerando mapas de distribuição potencial deespécies raras, endêmicas e ameaçadas de extinção. Entre os algoritmos mais utilizadosestá o Maxent, capaz de gerar predições com poucos pontos de presença. O objetivoprincipal deste trabalho é avaliar a aplicabilidade de modelos gerados pelo Maxent paraencontrar novas populações de plantas ameaçadas de extinção da Floresta Atlântica. Oprimeiro capítulo avalia duas espécies arbóreas com ampla distribuição geográfica(Melanoxylon brauna Schott e Dalbergia nigra (Vell.) Allemao ex Benth., Fabaceae),sendo que os dados de ocorrência apresentam baixa precisão geográfica, e as variáveisambientais baixa resolução. Para gerar os modelos foram utilizados os métodos MaxentLPT e o Maxent T10. Os mapas resultantes podem ser interpretados como umaaproximação razoável da distribuição potencial das espécies, com menos de 25 pontosde ocorrência. A taxa de acerto para M. brauna foi de 63% (LPT) e 83%(T10), enquantoque para D. nigra foi de 40% (LPT) e 75% (T10). De acordo com os resultados dotrabalho de campo, os mapas gerados pelos modelos Maxent T10 obtiveram umamelhor acurácia em relação aos modelos Maxent LPT. Considerando o histórico desobreexploração ocorrida no passado e a área de ocupação encontrar-se severamentexviifragmentada, sugere-se que as espécies em estudo sejam mantidas na categoriaVulnerável nas listas de espécies ameaçadas de extinção conforme os critérios da IUCN.O segundo capítulo avalia a modelagem para uma espécie herbácea com distribuiçãogeográfica restrita (Petunia mantiqueirensis T. Ando & Hashim., Solanaceae) comapenas oito pontos de ocorrência, com coordenadas mais precisas que as espéciesarbóreas estudadas no primeiro capítulo. Os modelos apresentaram uma taxa de acertode 87%, sendo considerado estatisticamente significante. Foram registradas nove novaspopulações da espécie em áreas previstas pelos mapas gerados. Os modelos dedistribuição geográfica potencial associados a trabalhos de campo mostraram-se úteispara aumentar o conhecimento sobre a distribuição geográfica atual de espéciesameaçadas de extinção.PALAVRAS-CHAVE: Modelos de distribuição geográfica potencial,MAXENT, espécies ameaçadas de extinção, Floresta Atlântica, Melanoxylon brauna,Dalbergia nigra, Petunia mantiqueirensis. ABSTRACTKAMINO, L.H.Y. (2009). Potential Models of Species Geographical Distribution: anessay with threatened species from Atlantic Forest. Ph.D. Thesis Instituto CiênciasBiológicas, Universidade Federal de Minas Gerais, Belo Horizonte. Advisor: JoãoRenato Stehmann.Potential Models of Species Distribution have been used as important tools inconservation biology, producing maps of expected distribution of rare, endemic andthreatened species. One of the most used algorithms is Maxent, that can predictdistribution with a few occurrence data. The main goal of this work is to evaluate thepredictive models generated by Maxent, as a tool to help finding new populations ofplants threatened of extinction in the Atlantic Forest. In the first chapter two tree specieswith large extent of occurrence are evaluated (Melanoxylon brauna Schott e Dalbergianigra (Vell.) Allemao ex Benth., Fabaceae), and the data of occurrence acquired fromherbarium sheets were of low geographic precision. To generate the models were usedthe Maxent LPT and T10 methods. The resulting maps exhibit na acceptable approachof the species potential distribution, with less then 25 ocurrence data. The set rate for M.brauna was of 63% (LPT) and 83% (T10), and for D. nigra of 40% (LPT) and 75%(T10), respectively. According to the results of the field surveys, the maps generated bythe T10 algorithm had a better accuracy than the LPTs. Considering the level offragmentation and the history of over exploitation of the occurrence area of the species,they are both recommended to be maintained as Vunerable, according to IUCN criteriafor threatened species. The second chapter evaluate the predictive model for one herbspecie of restricted distribution (Petunia mantiqueirensis T. Ando & Hashim.,xixSolanaceae), with only eight known registries, but with more precise references than thetrees of the first chapter. The models showed a set rate of 87%, what are consideredstatistically significant. Nine new populations of P. mantiqueirensis were found inpredicted areas of the model. The Potential Models of Geographical Distributionassociated with field trips were useful to enlarge the knowledge about the occupancyarea of threatened plant species.KEYWORDS: Potential Models of Species Geographical Distribution, Maxent,Threatened Species, Atlantic Forest, Melanoxylon brauna, Dalbergia nigra, Petuniamantiqueirensis.

Estima-se que, em poucos anos, muitas espécies poderão ser extintas, principalmente as endêmicas, que ocorrem em ambientes específicos e que sofrem com a perda e fragmentação de habitats causados pelas mudanças na cobertura da terra, sobretudo por fatores antrópicos. Para as espécies que possuem distribuição geográfica restrita, como é o caso das espécies Scinax cabralensis e Bokermannohyla sagarana, endêmicas da Serra do Cabral MinasGerais, a perda de habitat torna-se o fator mais influente no declínio populacional e na vulnerabilidade à extinção. A Serra do Cabral está sob fortes ameaças devido ao fogo predatório, conversões da cobertura vegetal nativa em monoculturas de Eucalyptus e Pinus e pastagem para o gado, levando a perda da biodiversidade local. Esta dissertação modelou a distribuição potencial de duas espécies de anfíbios endêmicos da Serra do Cabral, acessando áreas perdidas para monoculturas de Eucaliptus e Pinus bem como a área protegidapela unidade de conservação (Parque Estadual da Serra do Cabral). Utilizou-se o algoritmo MAXENT para modelar a associação entre adequalibilidade ambiental, variáveis bioclimáticas e de uso do solo. Ademais, recomendações sobre mudança de status de conservação das espécies são discutidas. O cálculo de perda de habitat, baseado nas áreas de silvicultura subtraídas da área modelada de adequabilidade ambiental (modelo sem inclusão de cobertura vegetal baseado em variáveis climáticas, declividade e altitude), mostrou que 10,99% da área adequada para a ocorrência de S. cabralensis e 10,58% da área adequada para B. sagarana foram perdidas devido à alteração da cobertura vegetal para monoculturas de Pinus e Eucalyptus considerando as distribuições que não possuem associação da vegetação na adequabilidade. De acordo com o modelo sem a variável vegetação, somente 15,16% da área com adequabilidade para Scinax cabralensis e 16,75% para Bokermannohyla sagarana estão protegidos pela Unidade de Conservação (UC). Tendo em vista os modelos desenvolvidos e a situação crítica da Serra do Cabral é proposta a mudança de status de conservação de Scinax cabralensis. Habitat loss and fragmentation are the main causes of species extinctions. Changes in land use lead to global environmental impacts and are mostly caused by humans. Many species are likely to become extinct in a few years, especially those that are endemic and occupy specific habitats. For species with restricted distribution, such as Scinax cabralensis and Bokermannohyla sagarana, endemic from the Serra do Cabral, in the southeastern of Brazil, habitat loss is likely to be the main cause of population decline and vulnerability to extinction. Species withsimilar attributes should be focused for conservation because their small range makes them more vulnerable to extinction due to decreases in genetic diversity, demographic stochasticity and environmental fluctuations. The Serra do Cabral is under pressure from illegal fires, cattle ranching and changes in land cover with Eucalyptus and Pinus plantations replacing native vegetation. All these changes are expected to decrease local biodiversity, and the assessment of their impacts is of utmost importance to assess the likelihood of species permanence. Thisthesis aims to provide baseline data for effective protection planning of two endemic frog species from the Serra do Cabral, analyzing to what extent land cover affects their distribution. Models of environmental suitability were generated using the software Maxent and climatic/topographic data. Vegetation was included as an additional variable in a second model. Habitat loss was estimated as the area covered by silviculture subtracted from the area predicted as suitable by the model without the variable vegetation. Habitat loss was 10,99%for S. cabralensis and 10,58% for B. sagarana. The model including vegetation cover showed only 15.16% of the predicted suitable area for Scinax cabralensis to be protected within the only a conservation unit at the region, as well as only 16.75% of the suitable area for Bokermannohyla sagarana. Given the above mentioned, propose changes in the conservation status of the Scinax cabralensis in the IUCN red list.

A Modelagem de distribuição geográfica potencial tem sido utilizada como uma importante ferramenta no manejo de espécies invasoras. A modelagem gera mapas que indicam áreas ambientalmente adequadas à ocorrência dessas espécies, sendo esses mapas resultados de procedimentos de otimização (correlações entre os registros de ocorrência da espécie alvo com variáveis ambientais). Estudos que analisam variáveis ambientais explicativas (chamadas de preditores ambientais) de padrões de ocorrência de espécies invasoras também têm contribuído no manejo dessas plantas. Entretanto, para determinadas comunidades biológicas, como por exemplo, macrófitas aquáticas, os estudos sobre essas abordagens apresentam investigações metodológicas que ainda necessitam de avaliação crítica. Nesse sentido, essa tese apresentará dois capítulos com discussões sobre os principias paradigmas metodológicos dos estudos sobre preditores ambientais ou distribuição geográfica potencial de macrófitas aquáticas, focando em espécies invasoras. No primeiro capítulo realizamos uma análise crítica da modelagem de distribuição geográfica potencial de macrófitas aquáticas, baseando-se em um estudo de caso com as invasoras Egeria densa e Eichhornia crassipes no rio São Francisco, Brasil. Nessa pesquisa avaliamos: a diferença entre a modelagem de macrófitas flutuantes e submersas fixa; o melhor conjunto de registros das espécies (registro de campo ou informações de herbário/artigo) ou de preditores ambientais (bioclimáticos ou limnológicos) nesses modelos; a influência da profundidade da coleta dos dados limnológicos (superfície x fundo) no desempenho dos modelos; e a importância da seleção estatística de preditores ambientais no processo de otimização. Os modelos foram computados a partir de processos de otimização (correlação entre os registros da espécie e preditores ambientais) através do algoritmo Maxent, sendo o teste binomial utilizado para comparar o desempenho dos modelos. Os modelos gerados para E. crassipes (flutuante) apresentaram erros de veracidade nos pontos de registros da espécie (independentemente da origem dos dados), sendo sua capacidade de deriva para ambientes com correnteza a provável causa desse viés metodológico. Modelos optimizados com registros de campo, preditores limnológicos coletados na superfície e/ou com seleção de preditores não colineares apresentaram os melhores desempenhos, independente da espécie alvo. O segundo capítulo da tese teve por objetivo investigar a presença de estrutura espacial na ocorrência de E. densa em ambientes semi-lóticos do rio São Francisco e, consequentemente, identificar e particionar a explicação do conjunto de preditores ambientais (limnológicos ou bioclimáticos) ou do A Modelagem de distribuição geográfica potencial tem sido utilizada como uma importante ferramenta no manejo de espécies invasoras. A modelagem gera mapas que indicam áreas ambientalmente adequadas à ocorrência dessas espécies, sendo esses mapas resultados de procedimentos de otimização (correlações entre os registros de ocorrência da espécie alvo com variáveis ambientais). Estudos que analisam variáveis ambientais explicativas (chamadas de preditores ambientais) de padrões de ocorrência de espécies invasoras também têm contribuído no manejo dessas plantas. Entretanto, para determinadas comunidades biológicas, como por exemplo, macrófitas aquáticas, os estudos sobre essas abordagens apresentam investigações metodológicas que ainda necessitam de avaliação crítica. Nesse sentido, essa tese apresentará dois capítulos com discussões sobre os principias paradigmas metodológicos dos estudos sobre preditores ambientais ou distribuição geográfica potencial de macrófitas aquáticas, focando em espécies invasoras. No primeiro capítulo realizamos uma análise crítica da modelagem de distribuição geográfica potencial de macrófitas aquáticas, baseando-se em um estudo de caso com as invasoras Egeria densa e Eichhornia crassipes no rio São Francisco, Brasil. Nessa pesquisa avaliamos: a diferença entre a modelagem de macrófitas flutuantes e submersas fixa; o melhor conjunto de registros das espécies (registro de campo ou informações de herbário/artigo) ou de preditores ambientais (bioclimáticos ou limnológicos) nesses modelos; a influência da profundidade da coleta dos dados limnológicos (superfície x fundo) no desempenho dos modelos; e a importância da seleção estatística de preditores ambientais no processo de otimização. Os modelos foram computados a partir de processos de otimização (correlação entre os registros da espécie e preditores ambientais) através do algoritmo Maxent, sendo o teste binomial utilizado para comparar o desempenho dos modelos. Os modelos gerados para E. crassipes (flutuante) apresentaram erros de veracidade nos pontos de registros da espécie (independentemente da origem dos dados), sendo sua capacidade de deriva para ambientes com correnteza a provável causa desse viés metodológico. Modelos optimizados com registros de campo, preditores limnológicos coletados na superfície e/ou com seleção de preditores não colineares apresentaram os melhores desempenhos, independente da espécie alvo. O segundo capítulo da tese teve por objetivo investigar a presença de estrutura espacial na ocorrência de E. densa em ambientes semi-lóticos do rio São Francisco e, consequentemente, identificar e particionar a explicação do conjunto de preditores ambientais (limnológicos ou bioclimáticos) ou do fator espaço nesse padrão de ocorrência, sendo essa investigação pioneira para de regiões tropicais. Entre 2006 e 2010, realizamos 12 expedições para coletar dados limnológicos e de ocorrência da espécie em 68 pontos amostrais, sendo coletadas informações adicionais de 19 variáveis bioclimáticas do BioClim. Realizamos análise multivariada (NMDS) e teste t para avaliar o ajuste da espécie para ambientes semi-lóticos do rio e correlogramas para testar autocorrelação espacial na variável resposta. Aplicamos seleções de modelos automáticos para identificar o conjunto de preditores ambientais e filtros espaciais explicativos do padrão de ocorrência da espécie e partição de variância para descriminar a explicação atribuída aos preditores ambientais e/ou espaciais nesses padrões. Os resultados confirmaram o ajuste de E. densa para ambientes lênticos do rio e a presença de estrutura espacial na variável resposta. Os modelos mais parcimoniosos indicaram a condutividade, fosfato inorgânico, fósforo total, transparência, turbidez e pH como os principais preditores ambientais da ocorrência de E. densa pelos ambientes semi-lóticos do rio. Nos modelos selecionados, a explicação atribuída ao fator espaço foi superior à indicada para os preditores ambientais, sendo a limitação da dispersão de E. densa influenciada pelos barramentos físicos desses ecossistemas. Em síntese, esta tese apresentou uma análise crítica sem precedentes das questões metodológicas e conceituais no que diz respeito à distribuição geográfica potencial ou predadores ambientais de macrófitas aquáticas invasoras, proporcionando uma ampliação do conhecimento sobre o manejo dessas plantas. Palavras-chave: Maxent, limnologia, modelagem, plantas aquáticas, seleção de modelos. The geographic distribution modelling is an important tool, which has been used for the management of invasive species. The modelling creates maps that indicate environmentally suitable areas for the occurrence of target species. Such maps are the result of optimization procedures (correlations between the occurrence records of the target species and environmental variables). Studies that analyze explanatory environmental variables about the patterns of occurrence of invasive species have also contributed to the control of invasive plants. However, for certain biological communities, for instance macrophytes, studies with such approaches still lack methodological investigations with critical evaluation. This thesis comprises two chapters that discuss major methodological paradigms about the studies of environmental predictors and potential geographic distribution of aquatic plants, using invasive species as study models. The first chapter refers to a critical analysis of the potential geographic distribution modelling of aquatic macrophytes, analyzing two invasive species, Egeria densa and Eichhornia crassipes, in the São Francisco River, northeastern Brazil. This research evaluates: differences between the modelling of floating and submerged fixed macrophytes; best records of the species (field records or herbarium/article information) or environmental predictors (Bioclimatic or limnological) in such models; the influence of the depth of collection of limnological data on the performance of the models; and the importance of statistic treatment of environmental predictors during optimization process. The models were computed after optimization process performed using the Maxent algorithm, and binomial tests were used to compare the efficiency of the models. The models for E. crassipes (floating species) showed veracity errors on the recorded points of occurrence (regardless of the data source), which is probably due to its capacity to drift in environments with water flow, causing such methodological bias. Optimized models with field records, limnologic predictors collected on the surface and/or with selected non-collinear predictors performed better than those generated using records obtained from herbaria/articles, with bioclimatic or limnologic predictors collected on the deep, and/or without statistical selection of environmental predictors. The second chapter analyzes the presence of spatial structure in the occurrence of E. densa in semi-lotic regions of the São Francisco River. Also, we identified and partitioned the explanation of the set of environmental predictors (limnology or bioclimatic) or of the space factor on its occurrence pattern. Between 2006 and 2010, we conducted 12 expeditions to collect limnologic and occurrence data of the analyzed species at 68 sampling points. Additionally, the information of 19 bioclimatic variables were collected from BioClim. We performed multivariate analysis (NMDS) and t test to evaluate the adjustment of E. densa to semi-lotic environments of the river, and used correlograms to test spatial autocorrelation in the response variable. We applied automatic selection of models to identify the set of environmental predictors and spatial filters that explain both the patterns of occurrence of E. densa and the partition of variance. The results confirmed the adjustment of E. densa for lentic environments, and the presence of space structure. The most parsimonious model indicated that conductivity, inorganic phosphate, total phosphorus, transparency, turbidity, and pH are the main environmental predictors of the occurrence of E. densa for semi-lotic environments in river. Selected models show that the explanation attributed to the space factor was greater than that of environmental predictors, and that physical barriers in these ecosystems limited the dispersion of E. densa. In short, this thesis provides an unprecedented critical analysis of the methodological and conceptual issues concerned to the potential geographic distribution or environmental predictors of invasive aquatic macrophytes, allowing new insights into the knowledge and management of such plants.

A face da Terra está em constante transformação. Em consonância com isso, as espécies vegetais, em particular, estão sempre se (re)organizando em diferentes escalas de tempo e espaço em associação com as mudanças de fatores bióticos e físicos. Em especial na América do Sul, próximo a latitude que marca o Trópico de Capricórnio, nota-se uma grande diversidade de fitofisionomias. Padrões disjuntos de espécies denunciam uma possível comunicação pretérita entre formações vegetacionais semelhantes, mas hoje separadas por extensas áreas com vegetação e ambiente contrastantes. Com o objetivo de investigar a comunicação entre as formações vegetacionais que ocorrem, principalmente, na região central do continente Sul Americano, este trabalho pretende, através da Modelagem de Distribuição Potencial de Espécies, para o presente e passado, propor uma possível conexão ou corredor de dispersão das espécies arbóreas com distribuição disjunta nos Domínios Andino e Atlântico. Para isso, foram extraídos do banco de dados NeoTropTre listagens de espécies e dados Bioclimáticos. Foi feita uma modelagem das correlações atuais entre os padrões de variação da composição atual da flora arbórea, como resposta, e variáveis climáticas e espaciais como preditoras. As variáveis preditoras selecionadas foram empregadas em modelagens da distribuição atual e pretérita de três subconjuntos de espécies com distribuição disjunta (florestas nebulares, estacionais e pluviais). Foram construídos modelos preditivos para os últimos períodos Último Interglacial e Glacial Máximo do Pleistoceno, para o período do Holoceno Médio e Atual. As previsões geradas foram representativas de acordo com os parâmetros utilizados para a validação dos modelos. Os modelos gerados mostram uma possível mudança de ocupação das espécies ao longo dos períodos considerados. Para o período do Último Interglacial, o modelo sugere a formação de uma conexão ou corredor de dispersão entre os Domínios Andino e Atlântico localizada em região sub-tropical. O modelo para o período do Último Glacial Máximo, também sugere a formação de um corredor de dispersão ligando os Domínios formado em região tropical. Para os períodos Holoceno Médio e o Atual não há formação de corredores de dispersão que ligam os dois domínios. Para esses dois últimos períodos podemos observar a formação de dois Núcleos distintos representando os Domínios Andino e Atlântico em um padrão disjunto. O resultado alcançado com a modelagem sugere que o clima é um importante fator que promove a separação entre os dois Domínios Andino e Atlântico ao longo do tempo. The face of the Earth is keep changing. In agree with this, the plant species, in particular, are always (re)organizing themselves in different scales of time and space, in association with biotic and physic factors changes. Especially in South America, it is possible to observe a great vegetation mosaic that suggests an environmental dynamism. Near to the latitude that marks the Capricorn Tropic, we can notice a big diversity of phytophysiognomy that, although they are distinct, they have some resemblance in its floristic composition. Furthermore, disjunct species pattern shows a possible past link between similar vegetations groups, but today, separated for extensive areas with contrasting environmental and vegetation. With the aim of investigate the link between the groups of vegetation that occur, mainly, in South Americas central region, this study intends, through Potential Species Distribution Modeling, to the present and past time, propose a possible connection or a dispersal corridor of the tree species with disjunct pattern in the Andes and Atlantic Domains. In order to do that, the data were extracted from NeoTropTree data base listing of species and environmental of WorldClim 1.4. Was made a modelling of currents correlations between the patterns of variations of the currents composition of the tree flora, how answer, and climates variables and spaces with predictors. The predictors variables selected, were employed in modelling of currents and past distributions of three subset (cloud, seasonal and rain forest). The past modeling were applied to the last pre-Glacial and Pleistocene Glacial periods, and to Middle-Holocene episodes. The generated predictions were representative according to the used parameters for the models validation. The generated models show a possible change in the species occupation over the considered period with the connections formation between the Andes and Atlantic Domains in the Last Integlacial and Last Maximo Glacial, suggesting, therefore, the formation of species dispersal corridor, nowadays, disjuncts

A constante redução dos habitats naturais é a grande responsável pela perda crescente de diversidade biológica. Sendo assim,entender a relação espacial entre uma espécie e seu habitat pode ser uma importante ferramenta de conservação. Esta pesquisa avaliou a acurácia e a similaridade de predições do habitat para quatro espécies da Mata Atlântica usando o método bayesiano Pesos de Evidências(WoE) e a Máxima Entropia(MaxEnt). As análises para WoE obtiveram um valor superiora 0.7 no teste TSS(TrueSkillStatistics) para três das quatro espécies modeladas, enquanto MaxEnt obteve valor superior a0.7 para todas as quatro. As avaliações de duplo sentido, Similaridade Recíproca entre as classificações de WoE e MaxEnt, ficaram no limite de 33-38% para a menor similaridade e 73-86% para a maior. Os resultados sugerem que o método de Pesos de Evidências como possível método alternativo para modelagem de adequabilidade do habitat, com vantagens claras na exploração das dimensões do nicho ecológico de espécies modeladas. Contudo, mais pesquisas são necessárias para melhor entender suas limitações e para identificar eventuais melhorias de desempenho do modelo.

Táxons endêmicos são aqueles com ocorrência restrita a uma área específica. O interesse por estes táxons vem auxiliando na elaboração de medidas conservacionistas por todo o mundo. A flora do Brasil, extremamente rica, é constituída por cerca de 41.215 espécies de plantas vasculares, das quais, aproximadamente, 18.080 são endêmicas. No estado de Minas Gerais existem cerca de 2.158 espécies endêmicas. A Serra do Espinhaço, localizada em Minas Gerais, é classificada como um centro de endemismo. Dentro da Serra do Espinhaço, em sua porção extremo-sul, está inserido o Quadrilátero Ferrífero, uma área de alto valor minerário que sofre com o aumento das atividades antrópicas locais nos últimos anos. O Quadrilátero Ferrífero é classificado como uma região prioritária para conservação, e o conhecimento de sua flora endêmica ressalta o foco da importância dessa conservação. Desta forma, os objetivos deste trabalho são: conhecer a flora endêmica do Quadrilátero Ferrífero e avaliar o padrão de riqueza de endemismos da região e modelar a distribuição geográfica potencial das espécies endêmicas. O levantamento das espécies endêmicas foi realizado a partir de consultas à bibliografia, coleções botânicas e coletas em campo. Resultando em 27 famílias botânicas, 50 gêneros e 95 espécies. Destas, 92 são angiospermas, duas monilófitas e apenas uma licófita. O mapa de riqueza gerado a partir dos registros das espécies sugeriu a existência de 13 áreas de endemismos no Quadrilátero Ferrífero. A análise de similaridade florística entre elas, a partir uso do coeficiente de Jaccard, comprovou a baixa similaridade, apresentando-se maior entre Itatiaiuçu (IA) e Sabará (SA) (0,50), com três espécies em comum. Os modelos de distribuição potencial foram gerados pelos algoritmos Distância Ambiental Eucludidana, BIOCLIM e MaxEnt. Seus resultados sugeriram áreas potencialmente mais ricas em espécies endêmicas, principalmente associadas às altitudes mais elevadas e consequentemente com maiores interesses pelas atividades minerárias. O presente trabalho evidencia a necessidade de medidas conservacionistas na área de estudo, que abriga um elevado número de espécies endêmicas, poucas Unidades de Conservação de Proteção Integral e excessivas atividades antrópicas nos últimos anos. Endemic taxon are those with occurrence restricted to a specific area. The interest in these taxon has been assisting in the development of conservation measures throughout the world. The flora of Brazil, extremely rich, consists of approximately 41.215 species of vascular plants, of which about 18.080 are endemic. In the state of Minas Gerais there are about 2,158 endemic species. The Espinhaço Range, located in Minas Gerais, is classified as a center of endemism. Within the Espinhaço Range, in the far south portion, is inserted the Quadrilátero Ferrífero, a high value mining area that suffers with the increase of local anthropogenic activities in recent years. The Quadrilátero Ferrífero, is classified as a priority area for conservation and the knowledge of its endemic flora emphasizes the importance of conservation. So, the objectives of this study are: to know the endemic flora of the Quadrilátero Ferrífero, to evaluate patterns of endemism richness of the region and model the potential geographical distribution of endemic species. The survey of the endemic species was conducted from bibliography research, botanical collections and gathering in the field. The result is 27 botanic families, 50 gender and 95 species. Of these, 92 are angiosperms, two are monilophytas and only one is a lycophytes. The map of richness generated from the records of the species suggested the existence of 13 areas of endemism in the Quadrilátero Ferrífero. The analysis of floristic similarity between them, using the Jaccard coefficient, showed low similarity, presenting higher level among Itatiaiuçu (IA) and Sabará (SA) (0.50), with three species in common. The Potential Models of Species Distribution were generated by the algorithms Environmental Euclidean Distance, BIOCLIM and MaxEnt. Their results suggested areas potentially richer in endemic species, mainly associated with higher altitudes and therefore with greater interest by mining activities. This study highlights the necessity for conservation measures in the study area, which protects a large number of endemic species, few Units of Integral Protection Conservation and excessive human activities in recent years.

A família Bromeliaceae é composta por 58 gêneros e aproximadamente 3.172 espécies e com distribuição quase exclusivamente neotropical. O Brasil é um importante representante da diversidade de Bromeliaceae possuindo 42 gêneros e 1.207 espécies, sendo que 85% destes táxons são endêmicos ao seu território. Em Minas Gerais, devido ao número de espécies endêmicas, dois ambientes são de especial importância para a família: os campos rupestres e os campos de altitude. Entretanto, os trabalhos de levantamentos florísticos com a família não contemplam satisfatoriamente essas áreas. Os objetivos desse trabalho são: 1) Realizar o levantamento florístico e o tratamento taxonômico das espécies de Bromeliaceae no Parque Nacional do Caparaó, uma área de campo de altitude inserido numa matriz florestal de Mata Atlantica, localizado na divisa entre Minas Gerais e Espírito Santo (Capítulo I); 2) entender os padrões na distribuição das espécies de Bromeliaceae nas serras do sudeste do Brasil e avaliar a influência das variáveis climáticas na composição de espécies (Capítulo II). Para o levantamento florístico e tratamento taxonômico foram realizadas coletas no parque entre setembro de 2010 a outubro de 2011. O material foi depositado no herbário BHCB da Universidade Federal de Minas Gerais. Cada espécie identificada foi descrita, e posteriormente foram elaboradas chaves de identificação e ilustrações. Para as análises florísticas foram compilados levantamentos de 18 áreas com altitude acima de 800 m, localizadas no sudeste brasileiro. Foram realizadas análises de similaridade, ordenação e regressões múltiplas. O Parque Nacional do Caparaó apresentou 45 espécies de Bromeliaceae distribuídas em 11 gêneros, sendo Vriesea (16 espécies), Aechmea, Neoregelia e Nidularium (cinco espécies cada um) os gêneros mais diversos. A subfamília Bromelioideae foi a mais representativa com seis gêneros e 21 espécies, seguida por Tillandsioideae (três gêneros/20 espécies) e Pitcairnioideae (dois gêneros/4 espécies). A matriz florística contou com 199 espécies das quais 80% apresentaram registro em menos de três localidades. A composição de espécies é influenciada pela sazonalidade da precipitação (9,1%) e principalmente pela interação da variável climática com a estrutura espacial entre as áreas estudadas (61,9%). As localidades apresentaram distribuição ordenada em um gradiente leste-oeste, em que as áreas inseridas no domínio da Mata Atlântica se associaram e foram substituídas por áreas de Cerrado, no sentido do aumento da sazonalidade da precipitação. The Bromeliaceae family is composed by 58 genera and approximately 3172 species and distributed almost exclusively in the neotropical zone. Brazil is an important representative of the diversity of bromeliads with 42 genera and 1207 species, where 85% of these taxa are endemic to its territory. Two environment are particularly important for the family in Minas Gerais state, due to the number of endemic species: campos rupestres and campos de altitude. However, the floristic survey about this family do not include these areas satisfactorily. The aims of this study are: 1) Conduct the floristic surveys and taxonomic treatment of Bromeliaceae species in Caparaó National Park, an area of campo de altitude located on the border between Minas Gerais and Espirito Santo states (Chapter I), 2) to understand the distribution patterns of Bromeliaceae species in the mountains of southeastern Brazil and assess the influence of climatic variables on species composition (Chapter II). The floristic surveys were done in the area between September 2010 and October 2011. The material were deposited in the herbarium BHCB of Federal University of Minas Gerais. Each species identified was described, and were developed identification keys and illustrations. For the floristic analysis were compiled floristic surveys of 18 areas with an altitude above 800 m, located in southeastern Brazil. Analysis of similarity, ordering and multiple regressions were done. The Caparaó National Park presented 45 bromeliads species distributed in 11 genera, being Vriesea (16 species), Aechmea, Neoregelia and Nidularium (five species each) the most diverse genera. The subfamily Bromelioideae was the most representative with six genera and 21 species, followed by Tillandsioideae (three genera/20 species) and Pitcairnioideae( two genera/4 species). The floristic matrix included 199 species of which 80% were registered in less than three locations. The species composition is influenced by the precipitation seasonality (9.1%) and mainly by the interaction of climate variable with spatial structure among the studied areas (61.9%). Areas belonging to the rain forest were grouped and were gradually replaced by areas included in the cerrado, showing a gradient in the direction of increased seasonality of precipitation.

A eficiência de ações conservacionistas depende do conhecimento da distribuição geográfica das espécies. Porém, esse conhecimento está longe de ser alcançado para a maioria das espécies, principalmente para as que ocorrem em ambientes montanhosos tropicais, como os campos rupestres da Cadeia do Espinhaço, caracterizados por formar ilhas de vegetação nas partes mais altas das serras isoladas pela variação altitudinal. Essa descontinuidade e a dificuldade de acesso agravam a falta de conhecimento sobre a distribuição das espécies, que seria essencial para se estudar os processos evolutivos e ecológicos tão marcantes nesses ambientes. Vellozia auriculata e V. gigantea são exemplos desse problema, sendo conhecidas, inicialmente, pela distribuição em uma ou duas serras próximas, com novas ocorrências encontradas em esforços de levantamento da distribuição direcionados para essas espécies. Os modelos de distribuição de espécies (MDEs) têm se mostrado uma ferramenta útil para prever a distribuição das espécies e guiar pesquisas de campo para encontrar novos registros. O objetivo desse estudo foi utilizar o algoritmo Maxent para localizar novas populações de espécies endêmicas na Cadeia do Espinhaço e auxiliar medidas de ampliação, criação e manejo de Unidades de Conservação, além de quantificar a amplitude ambiental das ocorrências dessas espécies. Os MDEs associam os dados de ocorrência das espécies e a informação ambiental disponível para definir condições adequadas onde as populações possam ser mantidas e extrapolar a distribuição das espécies no espaço geográfico. A quantidade e a qualidade dos dados de ocorrência são cruciais para um bom resultado de predição dos modelos e aplicação à conservação. Contudo, além de escassos, a maioria dos dados encontra-se enviesada resultando em mapas com alto grau de incerteza. Diante disso, testou-se a influência do tamanho amostral e do viés espacial na predição de diferentes algoritmos (Bioclim, Domain, Distância Ambiental Euclidiana e Maxent) nesses ambientes marcados por grande diversidade de relevo, geologia e ambiental, utilizando essas duas espécies como exemplo. Novas localidades foram encontradas para ambas as espécies, sendo sete para V. auriculata e cinco para V. gigantea. Diante das ameaças antrópicas, da potencialidade de apresentarem uma viii diferença genética significativa do conhecido para a espécie, principalmente em extremos de distribuição, e da classificação Em Perigo, as espécies necessitam urgência de manejo e conservação. Os mapas gerados com números amostrais pequenos geraram predições satisfatórias para serem utilizados em ações exploratórias para guiar pesquisas de campo para todos os algoritmos, exceto para Bioclim, sendo que amostras maiores geraram mapas mais acurados. O Domain foi geralmente o menos sensível à influência do tamanho amostral e o menos influenciado pelo viés espacial, na qual foram mostrados um dos mais altos valores de AUC, com mapas praticamente idênticos aos gerados com a amostragem ótima, com todos os dados de ocorrência. A nova amostragem realizada em campo a partir dos registros conhecidos das espécies foi essencial para aumentar a acurácia dos mapas e encontrar novos registros em campo. Como esse é o primeiro tratamento dessa abordagem metodológica para os campos rupestres, os resultados obtidos tanto com a aplicação quanto com a avaliação de métodos podem servir de guia para estudos futuros de distribuição com espécies na Cadeia do Espinhaço, além de servir de comparação entre as diferentes abordagens de aplicabilidade e avaliação metodológica em modelagem de distribuição de espécies. The effectiveness of conservation actions depends on the knowledge of the geographical distribution of species. However, this knowledge is far from being achieved for most species, especially those occurring in mountainous tropical environments, such as the rocky fields (campos rupestres) of the Espinhaço Range, characterized by forming islands of vegetation in the higher parts of mountains isolated by altitudinal variation. This discontinuity and difficulty of access aggravate the lack of knowledge about the distribution of species, which would be essential for studying the evolutionary and ecological processes in these environments. Vellozia auriculata and V. gigantea are examples of this problem as they were initially known by the occurrence in only one or a couple of hills. New records have been found in survey efforts targeted for these species. Species distribution models (SDMs) have proved to be a useful tool to predict the distribution of species and guide field research in order to find new records. The aim of this study was to use the algorithm Maxent to locate new populations of endemic species in the Espinhaço Range and to assist actions to expand, creation and management of protected areas, in addition to quantify the environment range of the occurrences of these species. The SDMs associate species occurrence data and environmental information available to set appropriate conditions where populations can be maintained, and extrapolate the distribution of species in geographic space. The quantity and quality of occurrence data are the crucial points to a successful outcome prediction models and application to conservation. However, beyond scarce, most data are biased resulting in maps with high degree of uncertainty. Therefore, we tested the influence of sample size and the spatial bias in the prediction of different algorithms (Bioclim, Domain, Environmental Euclidean Distance and Maxent) in these environments marked by great topographical, geological and environmental diversity, using these two species as an example. New locations were found for both species, seven for V. auriculata and five for V. gigantea. Due to anthropogenic threats, potentiality of presenting a genetical divergence, especially in extremes of distribution, and the classification of "Endangered", these species need urgent conservation and management. In this study, the maps generated by all algorithms, except for BIOCLIM, from small sample x numbers generated satisfactory prediction for use in exploratory actions to guide field surveys, with larger samples generating more accurate maps. Domain was generally less sensitive to the influence of sample size and less influenced by the bias space, showing one of the highest AUC values, and almost identical to the maps generated from optimal sampling, including all the occurrence data. New sampling conducted in the field from the known records of the species was essential to increase the accuracy of the maps and find new records in the field. Because this is the first study using this methodological approach in the rocky fields, the results obtained with both the application and the evaluation of methods may serve as a guide for future studies of species distribution in the Espinhaço Range, and may also be used to comparison between different approaches of applicability and methodological evaluation in species distribution modeling.