Increasing air temperature and atmospheric CO2 levels may affect the distribution of invasive species. Whereas there is wide knowledge on the effect of global change on temperate species, responses ...of tropical invasive species to these two global change drivers are largely unknown. We conducted a greenhouse experiment on Terminalia catappa L. (Combretaceae), an invasive tree species on Brazilian coastal areas, to evaluate the effects of increased air temperature and CO2 concentration on seed germination and seedling growth on the island of Santa Catarina (Florianópolis, Brazil). Seeds of the invasive tree were subjected to two temperature levels (ambient and +1.6 °C) and two CO2 levels (ambient and ~650 ppmv) with a factorial design. Increased temperature enhanced germination rate and shortened germination time of T. catappa seeds. It also increased plant height, number of leaves and above‐ground biomass. By contrast, increased atmospheric CO2 concentration had no significant effects, and the interaction between temperature and CO2 concentration did not affect any of the measured traits. Terminalia catappa adapts to a relatively broad range of environmental conditions, being able to tolerate cooler temperatures in its invasive range. As T. catappa is native to tropical areas, global warming might favour its establishment along the coast of subtropical South America, while increased CO2 levels seem not to have significant effects on seed germination or seedling growth.
The detection and control of invasive alien species in marine ecosystems is especially challenging because it is difficult to visualize the full extension of an invasion, while control options are ...often limited. The invasive scleractinian coral
Tubastraea coccinea
have spread over 8000 km of the Atlantic coastline, from Florida in the USA to southern Brazil, mainly in association with oil and gas platforms. This invasive coral threatens endemic species, reduces native coral recruitment, and modifies communities and trophic interactions, posing a relevant threat to shallow Atlantic reefs. The main aim of our study was to assess the effectiveness of an ongoing
T
.
coccinea
control program by analyzing the results of control interventions on population structure and cover of the target species in its southern Atlantic limit of distribution. We also describe the reproductive effort of
T. coccinea
in a 12-month time span. Between 2012 and 2019, almost 14,000 colonies were removed, most of them of small size (< 5 polyps). The highest reproductive effort was observed in September. Changes in
T. coccinea
cover, population structure and potential local propagule supply were observed. Control activities led to a reduction in up to half the cover of the invaded area, maintained the majority of the population in non-reproductive sizes, and consequently lowered the potential local propagule supply. Our paper highlights the fundamental role of control in preventing the local spread of
T. coccinea
. Recommendations on management frequency and timing are also discussed in order to contribute to the improvement of management efficiency.
Civil society can play a relevant role in supporting local environmental management, as volunteer efforts can be carried out at low cost and therefore be sustained over time. We present in this paper ...the assessment of the effectiveness of a volunteer program for the control of invasive pines in a protected area (PA) in a coastal zone of southern Brazil. Volunteer work has been ongoing for 8 years and the current state of invasion was compared with three simulation scenarios of species distribution that considered suitable habitats for pine invasion. Our results suggest that management actions have been effective. In the absence of any control efforts, pine trees would cover a high percentage of suitable habitats within the PA. Eliminating adult pine trees that function as seed sources and not allowing the next generation to reach maturity has been an efficient control strategy that has led to changes in the population structure of pines in the PA. Reaching neighboring private property owners is key for the future effective control of pines in the area, as all sources of pine seeds need to be eliminated. The approach used in our study may be applied to broader spatial scales to provide a baseline for management efforts needed to effectively control non-native invasive species.
Restoration techniques tailored to grasslands are needed to improve the effectiveness of restoration in tropical landscapes. In this study, we investigated the joint effects of plant–soil legacies ...and soil inocula in native and invaded Cerrado grasslands to evaluate whether different microbial origins affect plant–soil feedbacks and the likelihood of restoration. Using two grass species, we measured aboveground biomass, and several plant traits over two growth cycles. Species responded differently to inocula and legacies. The legacy of the invasive Urochloa eminii and invaded soil inocula positively affected mycorrhizal colonization. The legacy of Diectomis fastigiata, a commonly used species in Cerrado restoration, resulted in a negative self‐feedback potentially limiting its effectiveness for restoration. The success of the invasive species was in part due to its broad ecological niche and its ability to cope with a broad range of soil conditions. Our research suggests soil inocula and legacies could be used to aid restoration efforts in the tropics, allowing restoration practitioners to stimulate the growth of species targeting functional traits for a given ecosystem.
Invasive non‐native trees cause structural and functional changes in plant communities, which tend to increase over time since invasion. Native vegetation responses after control operations provide ...important information for restoration.
We evaluated the effects of time since invasion and of pine control on plant community structure and on functional traits in a coastal open ecosystem in southern Brazil. We compared richness, diversity, abundance and cover of woody and non‐woody native plant species, as well as species composition and community‐weighted means (CWM) based on functional traits (dispersal syndrome, fruit type, maximum height and shade tolerance) of plant communities, in four conditions: a non‐invaded area, an area where pines were controlled (managed area), an area of recent invasion and an area invaded longer ago.
Woody species abundance, richness and diversity declined over time since invasion. However, while abundance recovered to the point of not differing from the non‐invaded condition in areas where pines were controlled, species diversity and richness were lower in the managed area than in the area that was never invaded. The effects of pine invasion on richness and diversity of non‐woody plants did not increase over time, but plant cover progressively diminished.
Woody and non‐woody species composition varied between the four conditions. Species composition similarity was lower between conditions for non‐woody than for woody species. CWM differed between the older invasion and the other conditions, determined especially by native plant height and shade tolerance. Taller plants and more shade tolerant native species were exclusively sampled in the older invasion.
Synthesis and application: Pine invasion reduced species abundance, plant cover, richness and diversity, altering the composition of plant community. The escalation of negative temporal effects of pine invasion was observed on the composition of woody and non‐woody species and on functional traits. Although pine control favoured the natural regeneration of non‐woody species, diversity of woody species in the area submitted to pine control was lower than in the non‐invaded condition. Restoration activities are therefore required to increase woody species diversity. These results provide relevant guidance for the restoration of coastal ecosystems following invasive pine control.
Resumo
Árvores exóticas invasoras causam profundas mudanças estruturais e funcionais em comunidades vegetais, as quais tendem a se acentuar em função do tempo de invasão. Respostas da vegetação nativa ao controle de espécies exóticas invasoras fornecem embasamento importante para a restauração de áreas invadidas.
Nós avaliamos o efeito do tempo de invasão e do controle de Pinus elliottii em parâmetros estruturais e funcionais de comunidades vegetais em um ecossistema costeiro no sul do Brasil. Comparamos riqueza, diversidade, abundância e cobertura de espécies nativas lenhosas e não lenhosas, assim como a composição de espécies e CWM (community‐weighted means) com base em atributos funcionais (síndrome de dispersão, tipo de fruto, altura máxima, tolerância à sombras) dessas comunidades vegetais, em quatro condições: área não invadida, área previamente invadida e na qual o controle de pínus foi realizado, área invadida recentemente e área invadida há mais tempo.
A abundância, riqueza e diversidade de espécies de espécies lenhosas declinaram com o aumento do tempo de invasão. Entretanto, enquanto a abundância foi recuperada em áreas onde os pínus foram controlados, não diferindo de áreas não invadidas, a riqueza e a diversidade de espécies lenhosas foram menores em áreas nas quais o controle foi feito quando comparadas às áreas não invadidas. Os efeitos em termos de riqueza e diversidade de espécies não lenhosas não foram acentuados com o tempo de invasão, mas a cobertura diminuiu progressivamente.
A composição de espécies lenhosas e não lenhosas variou entre as quatro condições. Uma menor similaridade da composição de espécies entre as condições foi observada para espécies não lenhosas do que para espécies lenhosas. CWM diferiu entre a invasão mais avançada e as demais condições, determinada especialmente pela altura e pela tolerância à sombra. Plantas mais altas e espécies tolerantes à sombra foram exclusivamente amostradas na área de invasão mais avançada.
Síntese e aplicações. A invasão por pínus levou à redução em abundância, cobertura, riqueza e diversidade de espécies, alterando a composição de espécies em comunidades invadidas. A intensificação dos efeitos temporais negativos da invasão foi observada na composição de espécies lenhosas e não lenhosas e na estrutura funcional das comunidades vegetais. Apesar das ações de controle terem favorecido a regeneração natural de espécies não lenhosas, a diversidade de espécies lenhosas foi menor em áreas submetidas ao controle quando comparadas com áreas não invadidas. Assim, ações de restauração são necessárias para aumentar a diversidade de espécies lenhosas. Esses resultados provêem diretrizes para a restauração de ecossistemas costeiros após o controle de árvores exóticas invasoras.
Pine invasion reduced native species abundance, plant cover, richness and diversity, with an increase over time since invasion. Species diversity and richness were lower in the managed area than in the area that had not been invaded. Restoration activities are therefore required to increase native species diversity.
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•Salix × rubens (hybrid crack willow) is invading Brazilian riparian ecosystems•Most individuals occurred exclusively along watercourses and floodplains•Water transport can facilitate ...hybrid crack willow dissemination•Cultivation and transport must include measures to prevent biological invasions•Such measures have still not been established by the government
Human activities have been increasing pressure on riparian zones, affecting social benefits these ecosystems provide. Invasive species use river corridors as pathways to spread and consequently impact these ecosystems. Willows (Salix spp.) are important tree invaders worldwide. The invasiveness of Salix × rubens and its possible detrimental effects on Brazilian ecosystems have never been addressed. We hereby report the occurrence and invasion of S. × rubens in the highlands of southern Brazil, providing guidelines for the control of established populations and recommendations for safe cultivation to reduce invasions and environmental impacts. Through rapid field surveys and car-conducted roadside surveys performed in different seasons, S. × rubens individuals were located, counted and georeferenced. We registered 1929 individuals growing mainly along watercourses at altitudes between 826 and 1648 m above sea level. Our data provide evidence that S. × rubens has developed populations more than 100 m away from plantations in less than 50 years, likely facilitated by water transport, occasionally forming pure stands along rivers and floodplains. We concluded that S. × rubens is invading riparian ecosystems and thus must be acknowledged as an invasive species in Brazil.
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.
Resumo Na meta 10 da Estratégia Global para a Conservação de Plantas está estabelecido que, até 2020, planos de manejo efetivos serão implementados para impedir novas invasões biológicas e para manejar áreas importantes para a diversidade de plantas e que estejam invadidas. A justificativa para a meta é que espécies exóticas invasoras usualmente são uma grande ameaça de extinção a plantas nativas, e assim devem ser excluídas de áreas que são destinadas à conservação de espécies vegetais, especialmente aquelas que são endêmicas e/ou estejam ameaçadas de extinção. No Brasil, apesar da maior parte dos planos de manejo de unidades de conservação federais reportarem a presença de espécies exóticas invasoras nessas áreas, um número bem limitado de planos já foi implementado. A Resolução CONABIO 05/2009, que estabelece uma estratégia nacional sobre espécies exóticas invasoras, não foi colocada em prática, sendo lentos os avanços em políticas e legislação focadas em espécies exóticas invasoras em nível federal. Para que políticas efetivas sejam desenvolvidas no Brasil, órgãos federais da área ambiental devem funcionar como pontos focais e coordenar ações para (1) identificar áreas prioritárias para a prevenção e o manejo de invasões biológicas, e (2) para manejar espécies exóticas invasoras, reduzindo impactos pelas mesmas provocados.
Invasion by non-native species is one of the major threats to the conservation of biodiversity and to the provision of ecosystem services by protected areas. Invasive species often co-occur in ...protected areas, represented by sparse, isolated individuals or populations in different stages in the process of invasion. Species invasiveness, habitat invasibility and impact also differ between ecosystems, so the risk of invasion varies. Besides, prioritization is required due to constraints on time, financial and other resources. Priority-setting is therefore key to help protected area managers invest efforts on biological invasions that offer the best chances of producing large-scale positive results at the lowest cost possible. A priority-setting scheme for the control of invasive non-native species in natural areas is presented in this paper. The scheme, based on field observations of species occurrences, was applied to the Itatiaia National Park (Brazil). Priorities are calculated from a combination of three criteria attributed to each occurrence: species risk of invasion considering local ecosystems, invasion stage, and species frequency. Data collected in the field in the Itatiaia National Park were used to calculate priorities for 50 non-native species (six animals and 44 plants) in four locations in the Park. The highest priorities were attributed to species of high risk in an early stage of invasion occurring in one site, whereas a few widespread species of low risk were given lower priority. The scheme has proven functional for setting priorities for the control of non-native species in the Itatiaia National Park and in many other protected areas in Brazil.
Furcraea foetida (L.) Haw. (Asparagaceae) is a non-native invasive plant in Brazilian coastal ecosystems. This study focused on characterizing its population structure in coastal dune vegetation in ...southern Brazil. We also assessed which community structure characteristics were associated with its invasion and verified whether its growth negatively affected richness, diversity, and cover of local plant communities. We registered 67 individuals of F. foetida, most of them large and potentially reproductive. The species was positively associated with greater cover and height of native plant species which seems to promote the establishment of F. foetida by reducing extreme temperatures at the ground level. Overall, F. foetida plants growth did not result in changes in cover, richness or diversity of the studied plant communities. However, changes in cover of dominant native species might be a consequence of growth of F. foetida plants. These changes could result in changes in the structure of local plant communities which must be assessed in long-term studies. From a preventive perspective, immediate control actions, public awareness campaigns and legal regulations are essential to minimize F. foetida impacts to local biodiversity.
In South American forests, the Japanese raisin tree (Hovenia dulcis Thunb.) is an invasive tree that produces capsuled fruits attached to peduncles that grow thick and fleshy when ripe. Several ...frugivorous birds are reported to be dispersal agents of H. dulcis. The spread of H. dulcis propagules to non-invaded sites was evaluated at a local spatial scale in deciduous forests in Southern Brazil, in order to propose management strategies to prevent the arrival of propagules of such species in non-invaded sites. Seed arrival via birds was assessed by five 0.6 × 0.6 m seed traps in each of the 10 × 10 m plots in non-invaded sites at different distances from invaded sites. Seed arrival was also compared between control plots and plots where all H. dulcis trees were felled within a 30m radius from the center of plots. A limitation in short distance seed dispersal by birds was observed in the study area. There was a negative exponential relationship between number of seeds and distance from H. dulcis trees to non-invaded sites, and a positive exponential dependence of the number of seeds found in seed traps on the basal area of H. dulcis. Felling H. dulcis trees was effective in reducing the arrival of seeds in non-invaded sites, resulting in significantly fewer seeds in managed plots than in control plots.
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