Biogeographical patterns, ecological drivers, and evolutionary mechanisms of plant invasions

Understanding and predicting organisms’ responses to novel environments is a key issue for global change biology. In this dissertation, I study biogeographical patterns of plant invasions in Brazil, explore some of their ecological drivers, and disentangle the gene-level mechanisms that cause introduced organisms to become successful or failed invaders. I found that, for the invasive flora of Brazil, species were not introduced to new regions at random and that a species’ reason for introduction and continent of origin were associated. Asian ornamental and African forage plants are overrepresented, and two families (Poaceae and Fabaceae) dominate the invasive flora of Brazil. To address the reason for the observed patterns, I studied 18 Pinus species introduced to Brazil. I found that biotic resistance reduced the rate of spread, but did not prevent invasions from happening. Also, mean values of species traits did not explain which species would have become naturalized or invasive. The number of source populations introduced for each species was the factor that best explained the observed pattern of invasion. These findings indicate that forests might not resist invasion by Pinus and support the hypothesis that propagule pressure is a driver of invasions with propagule diversity being a component of this mechanism. Next, I surveyed the ecological literature to explore reasons why invasive species are not always invasive. I found intraspecific variation in invasion success and explanations for this variation: low propagule pressure, abiotic resistance, biotic resistance, genetic constraints, and mutualist release. Finally, to understand mechanisms leading to variation in invasion success, I analyzed the spread of Pinus taeda in six forestry provenance trials. I found that range expansions of introduced P. taeda resulted from an interaction between genetic provenance and climate and that temperature and precipitation predict the invasive performance of particular provenances. Further, I found genotypes can occupy climate niche spaces different from those observed in their native ranges. Overall, my work demonstrates genotypes respond to climate in distinct ways, and these interactions affect the ability of populations to expand their ranges. The introduction of adapted genotypes is a key driver of naturalization of populations of introduced species

The naturalized flora of Brazil : a step towards identifying future invasive non-native species

Introduções de espécies mediadas por humanos são um dos fatores determinantes do Antropoceno. Espécies exóticas podem formar populações invasoras que afetam a biodiversidade, serviços ecossistêmicos e agropecuária. Neste trabalho, eu avalio os dados sobre espécies naturalizadas no Brasil da lista de plantas com semente da flora do Brasil e testo as hipóteses de que regiões mais populosas e biomas com menor área natural remanescente contêm mais espécies naturalizadas. A Mata Atlântica teve o maior número de espécies naturalizadas, enquanto o Pampa teve a maior proporção de espécies naturalizadas em relação ao total de espécies no bioma. O número de espécies naturalizadas foi afetado tanto pelo número de habitantes quanto pela proporção de vegetação remanescente nos biomas. A família Poaceae conteve o maior número de espécies naturalizadas em todos os biomas e, junto com as famílias Asteraceae e Fabaceae, foram as três famílias com maior número de espécies naturalizadas em cinco biomas. Não houve registro de espécies naturalizadas em todos os seis biomas. Entretanto, das 46 espécies naturalizadas em cinco biomas, metade são Poaceae. Os resultados indicam que a flora brasileira é atualmente composta por espécies nativas e naturalizadas. Análises formais dos riscos de invasão biológica e potenciais impactos negativos causados por espécies naturalizadas devem ajudar na definição de prioridades de manejo e na alocação de recurso para controle.Human-mediated species introductions are one of the defining factors of the Anthropocene. Non-native species can form invasive populations that affect biodiversity, ecosystem services, or farming. Here I summarized data on naturalized vascular species from the Brazilian list of seed plants and tested the hypotheses that more populated regions and biomes with less remaining natural vegetation harbor more naturalized species. The Atlantic Forest had the largest number of naturalized species, whereas the Pampa had the highest proportion of naturalized species in relation to the biome's total richness. The number of naturalized species was affected both by human population size and proportion of remaining natural vegetation. Family Poaceae had the highest numbers of naturalized species in all biomes, and, together with Asteraceae and Fabaceae, forms the top three families in number of naturalized species in five of the biomes. There were no records of species naturalized in all six biomes. However, of the 46 species naturalized in five out of six biomes, half were Poaceae. The results indicate that the Brazilian flora is currently composed both by native and naturalized species. Assessments of invasion risks and of impacts by naturalized species could help set management priorities and resource allocation towards control

Invasion and managment of Pinus taeda in mountain top grasslands of Pico Paraná State Park, Paraná, Brazil

Espécies exóticas invasoras são espécies introduzidas e estabelecidas que produzem descendentes viáveis e que se propagam a distâncias significativas da planta-mãe, podendo causar danos ao meio ambiente. O presente estudo teve como objetivo realizar as primeiras avaliações sobre esse processo de invasão e uma ação de manejo da planta exótica invasora Pinus taeda em três morros no Parque Estadual do Pico Paraná, Paraná, Brasil. O manejo foi realizado mecanicamente, com corte das plantas, e as primeiras respostas sobre a cobertura vegetal e a riqueza de espécies foram mensuradas dez meses após a ação de corte. Os resultados indicam que a população da espécie invasora no local do estudo tem aproximadamente 36 anos, que as plantas crescem num ritmo inferior à média de outros ambientes, que sob a influência de pínus a vegetação nativa apresentou menor porcentagem de cobertura e, finalmente, que após o corte e derrubada de pínus a vegetação apresentou menor riqueza. O manejo teve custo total de R$199,00 por hectare. Concluiu-se que os campos de altitude são habitats suscetíveis a invasão biológica por pínus e que o período de 10 meses foi insuficiente para se obterem conclusões consistentes sobre o controle mecânico por corte raso.Palavras-chave:Espécies exóticas invasoras; invasão biológica; Pinus taeda; Campos de Altitude; Parque Estadual do Pico Paraná. AbstractInvasion and managment of Pinus taeda in mountain top grasslands of Pico Paraná State Park, Paraná, Brazil. Invasive alien species are introduced from other ecosystems and establish, producing viable descendency that spread for significant distances from the mother plants, potentially cause damage to the environment. The aim of the current study is to evaluate the first responses of the invasion process and the results of Pinus taeda control on three mountain areas in the Pico Paraná State Park, Southern Brazil. The control was conducted mechanically by felling adult trees and pulling out seedlings. The first responses were measured ten months after felling, measuring plant coverage and species richness. Results indicate that the population of invasive pines in these areas is around 36 years old, growing at a slower rate when compared to the average growth in other habitats, that the pine trees impact the native vegetation by producing lower coverage and finally, that after felling the pine trees the native vegetation showed lower richness. The control method had a cost of R$ 199,00 (about US$100) per hectare. Conclusions are that high mountain grasslands are susceptible habitats for biological invasion by pine trees and that recurrent work needs to be done for more consistent elucidations.Keywords:Invasive alien species; biological invasion; Pinus taeda; grasslands; Atlantic Forest; invasive conifers. Invasive alien species are introduced from other ecosystems and establish, producing viable descendency that spread for significant distances from the mother plants, potentially cause damage to the environment. The aim of the current study is to evaluate the first responses of the invasion process and the results of Pinus taeda control on three mountain areas in the Pico Paraná State Park, Southern Brazil. The control was conducted mechanically by felling adult trees and pulling out seedlings. The first responses were measured ten months after felling, measuring plant coverage and species richness. Results indicate that the population of invasive pines in these areas is around 36 years old, growing at a slower rate when compared to the average growth in other habitats, that the pine trees impact the native vegetation by producing lower coverage and finally, that after felling the pine trees the native vegetation showed lower richness. The control method had a cost of R$ 199,00 (about US$ 100) per hectare. Conclusions are that high mountain grasslands are susceptible habitats for biological invasion by pine trees and that recurrent work needs to be done for more consistent elucidations

The economic costs of biological invasions in Central and South America: a first regional assessment

Invasive alien species are responsible for a high economic impact on many sectors worldwide. Nevertheless, there is a scarcity of studies assessing these impacts in Central and South America. Investigating costs of invasions is important to motivate and guide policy responses by increasing stakeholders’ awareness and identifying action priorities. Here, we used the InvaCost database to investigate (i) the geographical pattern of biological invasion costs across the region; (ii) the monetary expenditure across taxa and impacted sectors; and (iii) the taxa responsible for more than 50% of the costs (hyper-costly taxa) per impacted sector and type of costs. The total of reliable and observed costs reported for biological invasions in Central and South America was USD 102.5 billion between 1975 and 2020, but about 90% of the total costs were reported for only three countries (Brazil, Argentina and Colombia). Costs per species were associated with geographical regions (i.e., South America, Central America and Islands) and with the area of the countries in km2. Most of the expenses were associated with damage costs (97.8%), whereas multiple sectors (77.4%), agriculture (15%) and public and social welfare (4.2%) were the most impacted sectors. Aedes spp. was the hyper-costly taxon for the terrestrial environment (costs of USD 25 billion) and water hyacinth (Eichhornia crassipes) was the hyper-costly taxon for the aquatic environment (USD 179.9 million). Six taxa were classified as hyper-costly for at least one impacted sector and two taxa for at least one type of cost. In conclusion, invasive alien species caused billions of dollars of economic burden in Central and South America, mainly in large countries of South America. Costs caused by invasive alien species were unevenly distributed across countries, impacted sectors, types of costs and taxa (hyper-costly taxa). These results suggest that impacted sectors should drive efforts to manage the species that are draining financial sources.info:eu-repo/semantics/publishedVersio

The naturalized flora of Brazil: a step towards identifying future invasive non-native species

Abstract Human-mediated species introductions are one of the defining factors of the Anthropocene. Non-native species can form invasive populations that affect biodiversity, ecosystem services, or farming. Here I summarized data on naturalized vascular species from the Brazilian list of seed plants and tested the hypotheses that more populated regions and biomes with less remaining natural vegetation harbor more naturalized species. The Atlantic Forest had the largest number of naturalized species, whereas the Pampa had the highest proportion of naturalized species in relation to the biome's total richness. The number of naturalized species was affected both by human population size and proportion of remaining natural vegetation. Family Poaceae had the highest numbers of naturalized species in all biomes, and, together with Asteraceae and Fabaceae, forms the top three families in number of naturalized species in five of the biomes. There were no records of species naturalized in all six biomes. However, of the 46 species naturalized in five out of six biomes, half were Poaceae. The results indicate that the Brazilian flora is currently composed both by native and naturalized species. Assessments of invasion risks and of impacts by naturalized species could help set management priorities and resource allocation towards control

Ten years after the Brazilian survey on invasive alien species: advances, gaps, and future directions

http://dx.doi.org/10.5007/2175-7925.2016v29n1p133Em 2004, o Ministério do Meio Ambiente contratou a elaboração do Informe Nacional sobre Espécies Exóticas Invasoras, cujos objetivos eram a coleta, a sistematização e a divulgação de informações no Brasil. Neste artigo, revisamos o que existia de conhecimento científico e normativas legais sobre invasões biológicas no Brasil antes do Informe, fazemos uma avaliação dos avanços e lacunas nos 10 anos pós-Informe e sugerimos direções futuras. Encontramos 143 artigos científicos e 65 marcos legais sobre espécies exóticas invasoras publicados entre 1999 e 2014. Os dados indicam que o Informe Nacional representa um divisor de águas para o tema no Brasil, a partir do qual aumentou a frequência da publicação de normas legais e pesquisas científicas. Identificamos avanços, ainda que aquém do necessário para considerar o tema consolidado no país. Os avanços obtidos se devem em parte à mobilização do terceiro setor e a grupos de pesquisa trabalhando separadamente. Para os próximos anos devem ser promovidos projetos de pesquisa, manejo e gestão mais ambiciosos e relevantes para fazer avançar o tema no país, contribuir para seu avanço em termos globais, embasar ações práticas de manejo e consolidar um arcabouço legal integrado que efetivamente permita-nos prevenir, manejar e controlar invasões biológicas.http://dx.doi.org/10.5007/2175-7925.2016v29n1p133In 2004, the Brazilian Ministry of Environment issued a call for projects for a national survey on invasive alien species aimed at collecting, organizing and disseminating information on invasive alien species in Brazil. In this paper we review the existing scientific knowledge and legal regulations on biological invasions in Brazil prior to the National Survey, the progress made since then, the gaps persisting ten years later, and make recommendations for future work. We found 143 scientific papers and 65 legal regulations on invasive alien species published between 1999 and 2014. Data indicate the National Survey is a milestone on the subject in Brazil, as the publication of regulations and articles increased significantly after 2005. Although numerous advances were identified, they are not suficient for the topic to be considered consolidated in Brazil. Advances made were greatly due to the mobilization of civil society organizations and research groups working separately. More ambitious and relevant research and management projects are required in upcoming years to ensure the advancement of invasion science in Brazil in ways that may also contribute internationally. Finally, consolidating management practices and actions into an integrated legal framework is key to effectively enable the prevention, management and control of biological invasions.

Adaptive evolution and phenotypic plasticity during naturalization and spread of invasive species: implications for tree invasion biology

Although the genetic aspects of biological invasions are receiving more attention in the scientific literature, analyses of phenotypic plasticity and genotype-by-environment interactions are still seldom considered in tree invasion biology. Previous studies have shown that invasions of tree species can be affected by intraspecific phenotypic plasticity, pre-adaptation, and post-introduction evolution, and we suggest there are opportunities for new developments in this field. Here, we present a description of the use of quantitative and molecular genetics in tree invasion biology, and propose an approach based on common garden experiments, quantitative and molecular genetic methods to investigate the role of adaptive evolution, phenotypic plasticity, and genotype-by-environment interactions in tree invasions, particularly at the infraspecific level. We illustrate the utility of this approach using examples from quantitative genetic studies of Pinus and an example from a classical reciprocal common garden experiment with Acer species. By using this approach, researchers can test hypotheses about the role and strength of genetic and environmental effects on population-level invasiveness and gain insights into evolutionary processes that occur during biological invasions. Moreover, knowledge of phenotypic plasticity and local adaption of tree populations may help researchers improve assessments of invasion risk

Invasive species and the Global Strategy for Plant Conservation: how close has Brazil come to achieving Target 10?

Abstract Target 10 of the Global Strategy for Plant Conservation establishes that "Effective management plans are in place to prevent new biological invasions and to manage important areas for plant diversity that are invaded" by 2020. The rationale for the target is that invasive alien species are a major threat to native plants, and thus should be excluded from areas reserved for the conservation of plant species, especially when endemic and/or threatened. In Brazil, although most management plans report the presence of invasive alien species and the need for management in federal protected areas, there are only a very limited number of management plans implemented. The national strategy on invasive alien species, published as CONABIO Resolution 05/2009, has not been implemented, so progress on policies and legislation focused on invasive alien species at the federal level has been slow. In order to reach an effective development of public policies in Brazil, federal environmental agencies must function as focal points and be in charge of coordinating actions aimed at (1) identifying priority areas for preventing and managing biological invasions, and (2) managing invasive alien species and reduce their impacts