Biological invasions are currently an important cause of environmental degradation, but they also offer important insights on how species respond to changes in the environment. Invasive species affect native ecosystems, but they are also affected by them. Our new study evaluated how invasive populations of a non-native pine responded to climate and other environmental factors. Our results show that many plants at the forefront of six different invasions are growing faster and being more productive than the plants originally planted 40 years ago. Taken together, the capacity for adaptation to different conditions and evolution of increased growth rates make Pinus taeda an invasive species that requires management and control before its spread reaches large areas.

Amazon and Cerrado‐forested streams show natural fluctuations in leaf litter quantity along the time and space, suggesting a change on litter quality input. These natural fluctuations of leaf litter have repercussion on the organic matter cycling and consequently effects on leaf decomposition in forested streams. The effects of the quantity of leaf litter with contrasting traits on consumption by larvae of shredder insects from biomes with different organic matter dynamics have still been an understudied question. The Trichoptera Phylloicus spp. is a typical shredder in tropical headwater streams and keep an important role in leaf litter decomposition. Here, we assessed the consumption by shredder Phylloicus spp., from Amazonia and Cerrado biomes, on higher (Maprounea guianensis) and lower quality leaves (Inga laurina) in different proportions and quantities. Experiments were performed concomitantly in microcosms approaches, simulating Cerrado and Amazonian streams. Higher leaf consumption occurred in Cerrado microcosms. Litter quantity influenced negatively leaf consumption by shredders in Cerrado, in opposition to Amazonia, where consumption was not affected by leaf quantity. In both sites, we observed higher consumption by shredders in treatment with only M. guianensis and no difference between other treatments with mixture of leaves. In treatment with litter of I. laurina, we noted the use of substrate for case building (due to the higher leaf toughness), affecting the fragmentation process. Therefore, our results indicate that leaf litter quality drives the preference of consumption by Phylloicus larvae in Cerrado and Amazonia streams.

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Riparian forests provide abundant plant litter -mostly in the form of dead leaves (hereafter litter) -for both forest soils and adjacent stream ecosystems, supporting terrestrial and aquatic detritus-based food webs. Although the fate of litter is predominantly dependent on its chemical and physical traits, there is limited availability of data on those traits over large spatial scales or empirical comparisons of traits across tropical biomes. We filled this gap by exploring the differences and similarities of nine litter traits and their dependence on phylogenetics for 68 plant species from riparian forests across three continental-scale, South American biomes: Amazon, Atlantic Forest and Cerrado. All three biomes produced litter with similar percentages of carbon (C) and phosphorus (P), C:P mass ratios, specific leaf area and toughness. However, litter from the driest biome (Cerrado) was better defended chemically (higher phenolic content) and had lower nutritional quality (higher C:nitrogen [N] mass ratio) but showed lower nutritional limitation (lower N:P mass ratio) than litter from more humid biomes. We found no phylogenetic signal for traits after constructing a phylogenetic tree across all biomes, suggesting that trait differences across biomes were environmentally determined. However, a strong phylogenetic signal was observed for P in the Atlantic Forest, which indicates that closely related species have similar %P in that biome. Our Divergent litter traits of riparian plant species between humid and drier biomes within the tropics

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Terrestrial leaf litter is an essential energy source in forest streams and in many tropical streams, including Cerrado, litter undergoes biological decomposition mainly by fungi. However, there is a limited understanding of the contribution of isolated fungal species to in-stream litter decomposition in the tropics. Here we set a full factorial microcosms experiment using four fungal species (Aquanectria penicillioides, Lunulospora curvula, Pestalotiopsis submerses, and Pestalotiopsis sp.) incubated in isolation, two litter types (rapid and slow decomposing litter) and two nutrient levels (natural and enriched), all characteristics of Cerrado streams, to elucidate the role of isolated fungal species on litter decomposition. We found that all fungal species promoted litter mass loss but with contributions that varied from 1 to 8% of the initial mass. The fungal species decomposed 1.5 times more the slow decomposing litter and water nutrient enrichment had no effect on their contribution to mass loss. In contrast, fungal biomass was reduced by nutrient enrichment and was different among fungal species. We showed fungal contribution to decomposition depends on fungal identity and litter type, but not on water nutrients. These findings suggest that the identity of fungal species and litter types may have more important repercussions to in-stream decomposition than moderate nutrient enrichment in the tropics.