Running waters contribute substantially to global carbon fluxes through decomposition of terrestrial plant litter by aquatic microorganisms and detritivores. Diversity of this litter may influence instream decomposition globally in ways that are not yet understood. We investigated latitudinal differences in decomposition of litter mixtures of low and high functional diversity in 40 streams on 6 continents and spanning 113° of latitude. Despite important variability in our dataset, we found latitudinal differences in the effect of litter functional diversity on decomposition, which we explained as evolutionary adaptations of litter-consuming detritivores to resource availability. Specifically, a balanced diet effect appears to operate at lower latitudes versus a resource concentration effect at higher latitudes. The latitudinal pattern indicates that loss of plant functional diversity will have different consequences on carbon fluxes across the globe, with greater repercussions likely at low latitudes.

No abstract

No abstract

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

Para avaliação da efetividade das ações de restauração, o estudo de indicadores ecológicos torna-se necessário para verificação do potencial de sustentabilidade das áreas restauradas, dentre os processos ecológicos importantes para funcionalidade dos ecossistemas encontram-se o aporte de serapilheira e sua decomposição no solo. Este estudo objetivou avaliar como a deposição da serapilheira e a decomposição de detritos foliares são influenciadas pelas idades de restauração. Para isso, foram realizadas coletas mensais do material de serapilheira, tanto em áreas em processo de restauração como em ecossistema de referência. A produção de serapilheira foi menor nas áreas em processo de restauração, do que nos ecossistemas de referência. Contudo, o componente folha teve uma maior porcentagem nas áreas em restauração. As taxas de decomposição não apresentaram diferenças significativas entre as áreas de estudo, contudo houve diferenças quanto a variações temporais, sendo mais acelerada no período de seca, em todas as áreas.