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

A new invasive species in South America: Pinus oocarpa Schiede ex Schltdl.

Conifers have a long history of introductions into many parts of the world and are among the most notorious plant invaders. At least 20 species of the genus Pinus are now considered to be invasive in at least one region of the southern hemisphere. Here, we present a quantitative report of invasion by Pinus oocarpa in a relatively undisturbed vegetation of the Cerrado region of Brazil. The invasion front of P. oocarpa was 458 m distant from the area of introduction, which represents a mean rate of spread of 12.72 m year-1. The average density of invasive plants was 561 ind ha-1, with a maximum density of 1,212 ind ha-1. It is currently unknown if the studied invasive population has produced negative impacts on the invaded ecosystem. However, it would be safe to assume that with the observed densities and rate of spread, P. oocarpa could affect the native community that it invaded. An early response targeting the eradication of the invasive population could prevent these ecological costs

Invasions across secondary forest successional stages: effects of local plant community, soil, litter, and herbivory on Hovenia dulcis seed germination and seedling establishment

Species abilities for seed germination and seedling survival under different situations are good predictors of their capacity to colonize a broad range of habitats. Biotic conditions related to understory cover, and abiotic factors such as litter thickness and soil moisture can be determinants of plant establishment. We evaluated seed germination, seedling survival, and growth of the invasive tree Hovenia dulcis under experimental field conditions in three successional stages (open, semi-open, and closed vegetation) of a fragmented seasonal deciduous forest in southern Brazil. Our hypotheses were that H. dulcis seed germination, seedling survival, and seedling growth decrease along the successional gradient, that these factors are positively affected by soil moisture and percentage of bare soil, and negatively affected by understory cover and litter thickness. We also tested the hypothesis that herbivory on H. dulcis would decrease along the successional gradient. Our main finding was that H. dulcis can germinate and establish along all forest successional stages because it is shadetolerant. Abiotic factors were more important than biotic factors for seed germination. Soil moisture positively affected seed germination while litter thickness negatively influenced seed germination. Percentage of bare soil negatively influenced seedling survival. Germination rates were higher in closed vegetation, whereas seedling survival was higher in semi-open vegetation, and growth rates were higher in open vegetation. There was no difference in herbivory among successional stages. The results of our study show that intermediate forest succession stages congregate the most favorable conditions for H. dulcis establishment, likely making them more susceptible to invasion.Fil: Dechoum, Michele. Universidade Federal de Santa Catarina; BrasilFil: Zenni, Rafael D.. Universidade do Brasília; BrasilFil: Castellani, Tania. Universidade Federal de Santa Catarina; BrasilFil: Zalba, Sergio Martín. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rejmánek, M.. University of California at Davis; Estados Unido

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

A interpretação hermenêutica da norma jurídica e a análise do termo “trânsito em julgado da sentença” a partir da construção dos significados na obra tratactus logico-philosophicus de wittgenstein / Hermenetic interpretation of the legal standard and analysis of the term “transit in judgment of the sentence” from the construction of the meanings in wittgenstein's tratactus logico-philosophicus

Este trabalho apresenta a importância da interpretação hermenêutica da norma jurídica, vez que esta “concede vida” ao comando legal, evidenciando a importância de aspectos como linguagem, linguística e logica, seguindo com a análise do termo “Trânsito em Julgado”. Examinando os termos trazidos pelo legislador, investiga-se a construção da interpretação normativa dentro do tempo e do espaço, levando em conta fatos que possam influenciar dentro do ordenamento jurídico, para que chegando a uma conclusão quanto a determinada proposição legal, seja esta a mais próxima da realidade para a qual foi escrita e posteriormente interpretada. Embasado na interpretação hermenêutica da linguagem, parte-se da teoria emergente do livro Tratactus Logico-Philosophicus, de Wittgenstein, avultando a importância das investigações para o autor, a qual se da no mundo dos fatos, onde ocorre a totalidade inserida dentro de um espaço logico e temporal. Analisa-se o pressuposto de que os fatos descrevem a realidade, onde se utiliza da figuração para “montar” a correspondência dos objetos ou situações, exprimindo a realidade apreendida. Para Wittgenstein, a correspondência por semelhança entre figuração e realidade configura a forma logica, representando o sentido. Visando analisar o termo “trânsito em julgado” dentro do tempo e espaço, pauta-se a pesquisa pela linha da linguagem, figuração e análise histórica de fatores subjetivos que demonstram a necessidade da população brasileira em determinados períodos, mostrando os anseios na construção normativa que ira vigorar dentro do ordenamento jurídico, bem como no processo da interpretação normativa desde o inicio do vigor até a contemporaneidade

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

Evolutionary dynamics of tree invasions: complementing the unified framework for biological invasions

Evolutionary processes greatly impact the outcomes of biological invasions. An extensive body of research suggests that invasive populations often undergo phenotypic and ecological divergence from their native sources. Evolution also operates at different and distinct stages during the invasion process. Thus, it is important to incorporate evolutionary change into frameworks of biological invasions because it allows us to conceptualize how these processes may facilitate or hinder invasion success. Here, we review such processes, with an emphasis on tree invasions, and place them in the context of the unified framework for biological invasions. The processes and mechanisms described are pre-introduction evolutionary history, sampling effect, founder effect, genotype-by-environment interactions, admixture, hybridization, polyploidization, rapid evolution, epigenetics and second-genomes. For the last, we propose that co-evolved symbionts, both beneficial and harmful, which are closely physiologically associated with invasive species, contain critical genetic traits that affect the evolutionary dynamics of biological invasions. By understanding the mechanisms underlying invasion success, researchers will be better equipped to predict, understand and manage biological invasions

IPBES Invasive Alien Species Assessment: Chapter 1. Introducing biological invasions and the IPBES thematic assessment of invasive alien species and their control

Chapter 1: Introducing biological invasions and the IPBES thematic assessment of invasive alien species and their control of the Thematic Assessment Report on Invasive Alien Species and their Control of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services