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Insect–plant interactions occur in several ways and have considerable environmental and ecological importance. Many feeding strategies have evolved among herbivorous insects, with host–herbivore systems likely being influenced by trophobionts with ants. We investigated how these interactions vary across elevation gradients by evaluating the structure of the herbivorous insect community and ants associated with Baccharis dracunculifolia at three distinct elevations (800, 1100, and 1400 m a.s.l.) on a mountain in southeastern Brazil. Moreover, we evaluated the diversity and specialisation of interactions between herbivores and host plants along the elevational gradient. We sampled herbivores and ants on 60 plants at each elevation (totalling 180 plant individuals). Herbivore species composition differed among elevations, as did interaction diversity and specialisation. Richness and abundance of chewing insects increased with elevation, while β‐diversity among patches of the host plant was higher at the lowest elevation, probably due to the patchy occurrence of B. dracunculifolia. Richness and abundance of sap‐sucking insects were higher at the intermediate elevation, possibly due to local environmental conditions. We observed a positive relationship between ant and herbivore trophobiont richness on B. dracunculifolia. We found that interactions were more specialised and less diverse at higher elevations compared to the lowest elevation. Changes in vegetation and environmental variables shaped species distributions and their ecological interactions along the elevation gradient. Our study demonstrates that increased elevation changes the structure and patterns of interactions of the herbivore insect guilds associated with the host plant B. dracunculifolia. Ant effects depend on the context, the environment, and the species of ants involved, and are essential for the presence of insect trophobionts.

Abstract. Three specimens of Anopheles darlingi Root were found in the Volta Grande environmental reserve, an area influenced by the Rio Grande dam constructed by the Volta Grande hydroelectric plant in Conceição das Alagoas, Minas Gerais, Brazil. The mosquito An. darlingi is one of the main vectors of human malaria in Brazil due to feeding preference for human blood, a factor that is accentuated by endophilic behavior. The information recorded here may be helpful to local entomological surveillance toward monitoring impacts generated by hydroelectric reservoir formation, as the presence of this vector in this type of environment indicates a potential risk for malaria transmission.Keywords: Hydropower; Malaria; Monitoring; Mosquitoes; Vectors. Primeiro registro de Anopheles darlingi Root (Diptera, Culicidae) na Região do Reservatório de Volta Grande, Conceição das Alagoas, Minas Gerais, BrasilResumo. Três espécimes de Anopheles darlingi Root foram encontrados na reserva ambiental Volta Grande, na área de influência da barragem do Rio Grande construída pela usina hidrelétrica de Volta Grande, em Conceição das Alagoas, Minas Gerais, Brasil. O mosquito An. darlingi é um dos principais vetores da malária humana no Brasil, devido à sua preferência alimentar por sangue humano, um fator que é acentuado pelo comportamento endofílico da espécie. O presente relato poderá ser útil à vigilância entomológica local para monitoramento dos impactos gerados pela formação do reservatório hidrelétrico, uma vez que a presença deste vetor neste tipo de ambiente indica um risco potencial de transmissão da malária.

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Restoration of tropical riparian forests is challenging, since these ecosystems are the most diverse, dynamic, and complex physical and biological terrestrial habitats. This study tested whether biodiversity can predict ecosystem functions in a human-impacted tropical riparian forest. We explored the effects of several biodiversity components (taxonomic or functional groups) on different ecosystem functions associated with restored riparian forests. Overall, 49% of the biodiversity components showed positive effects on ecosystem functions, each component to a different degree. In general, our results showed that both taxonomic and functional biodiversity had strong effects on ecosystem functions indicating that floral and faunal biodiversity enhanced the multifunctionality of these restored riparian tropical forests. These findings indicate that in restored riparian forests, recovery of biodiversity is followed by improvement in important ecosystem functions that are the basis for successful restoration. Future research and policy for restoration programs must focus on restoring elementary faunal and floral components of biodiversity in order to promote ecosystem multifunctionality.

24The interaction between hemiparasites and their host plants is an important structuring 25 mechanism for plant communities. The mistletoe Struthanthus flexicaulis (Loranthaceae) is 26 widely distributed in the campo rupestre ecosystem and likely has an important role in 27 structuring the communities of which its hosts are part. The main goals of this study were to 28 investigate the effects of parasitism by S. flexicaulis on host plants in a degraded area of 29 campo rupestre and to determine how parasitism affects characteristics of the structure of this 30 plant community over time. We found that parasitized plants had smaller crowns and branch 31 growth, and suffered lower mortality compared to non-parasitized plants. Parasitism by S. 32 flexicaulis decreased dominance and increased the diversity and evenness of plants in the 33 community over time. Parasitism leads to competition with the host for water and nutrients, 34 which may decrease the performance of the host and, consequently, leading to host death. 35The high mortality of the most abundant plant species led to a restructured woody plant 36 community. These results reinforce the importance of parasitic plants as key species for 37 maintaining species diversity in plant communities. 38 39 Chain 41 42 43 44 45 46 47 48 49 3 50 51 52 53 54 Identifying the factors that control the distribution, abundance and diversity of species 55 is important to understand the structuring of ecological communities. Communities are 56 structured according to climatic and historical variations (e.g. dispersion and speciation, 57 migration and extinction), local physical conditions and interactions among species [1, 2]. 58 On a local scale, abiotic factors have an important influence on the structuring of plant 59 communities, such as the availability of water and soil nutrients [34] in addition to 60 interactions with other organisms, such as microbes and arbuscular mycorrhizal fungi [5, 6, 61 7]. In turn, the distribution of plant communities strongly affects the community structure of 62 other organisms that directly depend on them as resources, such as herbivores and parasitic 63 plants [8, 9, 10]. 64 Among parasitic plants, hemiparasites are those capable of photosynthesis, but 65 depend on their hosts for water and nutrients [11]. The susceptibility to attack by 66 hemiparasitic plants (determined by chemical, physiological and physical processes at the 67 parasite-host interface) varies between plant species, and therefore, local abundance and the 68 degree of susceptibility of plants in a community are key factors for the successful 69 colonization of hemiparasites in the environment [12, 13, 14]. In addition, the seeds of the 70 hemiparasitic plants are mostly dispersed by birds, which can lead to a differential deposition 71 of seeds on the host plants according to the preferences of the birds for certain perches [15, 72 16, 17]. Generally, larger plants with more branched tops are more attractive perches for 4 73birds, leading to a greater abundance...

Magnetic fields have been observed in massive Ap/Bp stars and presumably are also present in the radiative zone of solar-like stars. Yet, to date there is no clear understanding of the dynamics of the magnetic field in stably stratified layers. A purely toroidal magnetic field configuration is known to be unstable, developing mainly non-axisymmetric modes. Rotation and a small poloidal field component may lead to a stable configuration. Here we perform global MHD simulations with the EULAG-MHD code to explore the evolution of a toroidal magnetic field located in a layer whose Brunt-Väisälä frequency resembles the lower solar tachocline. Our numerical experiments allow us to explore the initial unstable phase as well as the long-term evolution of the magnetic field. During the first Alfven cycles, we observe the development of the Tayler instability with the prominent longitudinal wavenumber, m = 1. Rotation decreases the growth rate of the instability, and eventually suppresses it. However, after a stable phase, sudden energy surges lead to the development of higher order modes even for fast rotation. These modes extract energy from the initial toroidal field. Nevertheless, our results show that sufficiently fast rotation leads to a lower saturation energy of the unstable modes, resulting in a magnetic topology with only a small fraction of poloidal field which remains steady for several hundreds of Alfven travel times. At this stage, the system becomes turbulent and the field is prone to turbulent diffusion. The final toroidal-poloidal configuration of the magnetic field may represent an important aspect of the field generation and evolution in stably-stratified layers.