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Aim Location Time Period Major Taxa Studied Methods Results Main Conclusions The relationship between body size and trophic position (BS–TP) typically exhibits a positive correlation in aquatic foodwebs, but the strength of this relationship is contingent on ecosystem type and climate. Different hypotheses have been proposed to elucidate climate and ecosystem type effects on the BS–TP relationship for ray‐finned fish. However, our understanding of whether such a relationship evolved in a correlated fashion, spanning various climates and ecosystem types, remains limited.Temperate and tropical marine and freshwater ecosystems.Present to millions of years ago.Ray‐finned fish.We used a phylogenetic tree and TP and BS data of more than a thousand freshwater and marine ray‐finned fishes, from distinct climates and ecosystems, to investigate patterns on macroevolutionary time scales of the evolutionary correlation of BS and TP. As part of our investigation, we also ran analyses excluding herbivores and detritivores from the dataset, then further focusing solely on carnivores.We found distinct patterns of the BS–TP evolutionary correlation for different climates and ecosystems. The evolutionary correlation between BS and TP was significant for all ecosystem type–climate combinations, except for tropical freshwater ecosystems. The results remained consistent even after accounting for phylogenetic uncertainty and when excluding herbivores and detritivores from the analysis.We found a weaker evolutionary correlation between BS and TP in tropical freshwater ecosystems. These findings are consistent with the stronger BS–TP relationship between extant taxa in temperate climates compared to the tropics, illustrating how evolutionary dynamics might have influenced the trophic structure of fish and contributed to shaping macroecological patterns of the BS–TP relationship. Our findings suggest that limitations that hinder evolutionary integration between BS and TP might be primarily attributed to energetic constraints imposed by temperature and the availability of C‐rich food resources at the base of the foodweb. [ABSTRACT FROM AUTHOR]

The diversity effect on decomposition, through the litter-mixing effects plays a central role in determining the nutrient and carbon dynamics in ecosystems. However, the litter-mixing effects are centered on a leaf litter perspective. Important aspects related to intraspecific interaction and biomass concentration are rarely evaluated, even though they could be essential to determine the litter decomposition dynamics. To our knowledge, we introduced a new perspective to evaluate whether and how the interaction between flower and leaf litter affects the occurrence, direction, and magnitude of litter-mixing effects in terrestrial and aquatic ecosystems. We performed laboratory experiments using flower and leaf litter from the yellow trumpet tree Tabebuia aurea (Silva Manso) Benth. and Hook. f. ex. S. Moore as a model. To obtain realistic results, we manipulated various scenarios of flower : leaf litter biomass proportion and measured 13 functional traits. Litter-mixing effects were consistent in both aquatic and terrestrial environments, with faster decomposition of both litter types in mixtures compared to their monocultures (synergistic effects). Litter-mixing effects were stronger in the terrestrial environment and at higher flower : leaf litter biomass proportions. Our results indicate that synergistic outcomes are mainly associated with complementary effects. Flower litter had a higher concentration of labile C compounds, N, P, and K and lower lignin concentrations, representing a labile litter, while leaf litter had a higher concentration of lignin, Ca, Mg, and Na, representing a refractory litter. Our results demonstrate the importance of litter-mixing effects between flower and leaf litter via complementary effects. These results shed light on the secondary consequences of flower litter on decomposition, suggesting that species with high reproductive investment in flower biomass may play an important role in the nutrient and carbon recycling of diverse plant communities, exerting a pivotal role in biogeochemical dynamics. [ABSTRACT FROM AUTHOR]

The diversity effect on decomposition, through the litter-mixing effects, plays a central role in determining the nutrient and carbon dynamics in ecosystems. However, the litter-mixing effects are centered on a leaf litter perspective. Important aspects related to intraspecific interaction and biomass concentration are rarely evaluated, even though they could be essential to determine the litter decomposition dynamics. Here, we introduced a new perspective to evaluate whether and how the interaction between flower and leaf litter affects the occurrence, direction, and magnitude of litter-mixing effects in terrestrial and aquatic ecosystems. We performed laboratory experiments using flower and leaf litter from the yellow trumpet tree Tabebuia aurea (Silva Manso) Benth. & Hook. f. ex. S. Moore as a model. To obtain realistic results and a mechanistic understanding, we used different scenarios of flower:leaf litter biomass proportion and measured 13 functional traits, respectively. Litter-mixing effects were consistent in both aquatic and terrestrial environments, with faster decomposition of both litter types in mixtures compared to their monocultures (synergistic effects). Litter-mixing effects were stronger in the terrestrial environment and higher flower:leaf litter biomass proportion. Our results indicate that synergistic results are mainly associated with complementary effects. Flower litter had a higher concentration of nutrients important to decomposition, such as N, P, K, and water-holding capacity, while leaf litter had a higher concentration of Ca, Mg, and Na. To our knowledge, this is the first study to demonstrate the importance of litter-mixing effects between flower and leaf litter. This result sheds light on the secondary consequences of flower litter on decomposition, suggesting that species with high reproductive investment in flower biomass may play an important role in the nutrient and carbon recycling of diverse plant communities, exerting a pivotal role in biogeochemical dynamics. [ABSTRACT FROM AUTHOR]

The diversity effect on decomposition, through the litter-mixing effects, plays a central role in determining the nutrient and carbon dynamics in ecosystems. However, the litter-mixing effects are centered on a leaf litter perspective. Important aspects related to intraspecific interaction and biomass concentration are rarely evaluated, even though they could be essential to determine the litter decomposition dynamics. Here, we introduced a new perspective to evaluate whether and how the interaction between flower and leaf litter affects the occurrence, direction, and magnitude of litter-mixing effects in terrestrial and aquatic ecosystems. We performed laboratory experiments using flower and leaf litter from the yellow trumpet tree Tabebuia aurea (Silva Manso) Benth. & Hook. f. ex. S. Moore as a model. To obtain realistic results and a mechanistic understanding, we used different scenarios of flower:leaf litter biomass proportion and measured 13 functional traits, respectively. Litter-mixing effects were consistent in both aquatic and terrestrial environments, with faster decomposition of both litter types in mixtures compared to their monocultures (synergistic effects). Litter-mixing effects were stronger in the terrestrial environment and higher flower:leaf litter biomass proportion. Our results indicate that synergistic results are mainly associated with complementary effects. Flower litter had a higher concentration of nutrients important to decomposition, such as N, P, K, and water-holding capacity, while leaf litter had a higher concentration of Ca, Mg, and Na. To our knowledge, this is the first study to demonstrate the importance of litter-mixing effects between flower and leaf litter. This result sheds light on the secondary consequences of flower litter on decomposition, suggesting that species with high reproductive investment in flower biomass may play an important role in the nutrient and carbon recycling of diverse plant communities, exerting a pivotal role in biogeochemical dynamics. [ABSTRACT FROM AUTHOR]

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 findings suggest that litter from more humid biomes was higher in nitrogen, although more phosphorus‐limited, than litter produced in drier climates such as that of the Cerrado biome. [ABSTRACT FROM AUTHOR]

We utilized laboratory microcosms to evaluate the effects of a benthic sediment bioturbator (Heteromastus similis; Polychaeta; conveyor-belt deposit feeder) on vertical distributions of C[H.sub.4] in sediment and net C[H.sub.4] fluxes across sediment-water-air interfaces. The effect of H. similis on sediment C[H.sub.4] concentration ([C[H.sub.4]]) varied depending on sediment depth and was strongest at higher animal densities. In comparison with defaunated controls, microcosms with the highest density of H. similis exhibited an increase in [C[H.sub.4]] of 3.7-fold, on average, at the sediment surface (0-2 cm), but these concentrations decreased by ~2-fold in deeper sediment layers (2-8 cm). However, irrespective of sediment depth, the density of H. similis resulted in an overall nonlinear reduction of bulk sediment [C[H.sub.4]]. Most of the observed C[H.sub.4] losses from the sediment were due to C[H.sub.4] oxidation, but the bioturbatory activities of H. similis also promoted significant increases in [C[H.sub.4]] in both the water column and the microcosm headspace. These results suggest that benthic invertebrates can mediate C[H.sub.4] turnover between compartments in aquatic ecosystems, with further consequences for the coupling between benthic-pelagic food chains via the methanotrophic-mediated microbial loop, as well as increase C[H.sub.4] emissions to the atmosphere. Des microcosmes de laboratoire nous ont servi a evaluer les effets d'un perturbateur biologique des sediments benthiques (Heteromastus similis; polychete qui se nourrit de sediments par convoyage) sur la repartition verticale de C[H.sub.4] dans le sediment et les flux nets de C[H.sub.4] a travers les interfaces sediment-eau-air. L'effet d'H. similis sur les concentrations de C[H.sub.4] ([C[H.sub.4]]) varie en fonction de la profondeur du sediment et est maximal aux plus fortes densites d'animaux. En comparaison des temoins sans animaux, les microcosmes avec les densites les plus elevees d'H. similis montrent une augmentation de [C[H.sub.4]] de 3,7 fois en moyenne a la surface des sediments (0-2 cm), mais ces concentration diminuent de ~2 fois dans les couches plus profondes de sediment (2-8 cm). Cependant, quelle que soit la profondeur des sediments, la densite d'H. similis cause une reduction generale non lineaire du [C[H.sub.4]] du sediment global. La plupart des pertes de C[H.sub.4] observees dans les sediments sont dues a l'oxydation de C[H.sub.4]; cependant, les activites de perturbation biologique d'H. similis provoquent aussi des augmentations significatives de [C[H.sub.4]], tant dans la colonne d'eau que dans l'espace de tete du microcosme. Ces resultats laissent croire que les invertebres benthiques peuvent servir d'agents dans le circulation du C[H.sub.4] entre les compartiments des ecosystemes aquatiques, avec des consequences additionnelles sur le couplage des chaines alimentaires benthique et pelagique par l'intermediaire de la boucle microbienne methanotrophique, ainsi que sur l'accroissement des emissions de C[H.sub.4] vers l'atmosphere. [Traduit par la Redaction], Introduction Inland aquatic ecosystems such as wetlands, rice fields, and shallow lakes are major sources of the C[H.sub.4] that is released into the atmosphere (Bartlett and Harriss 1993; Whiting and [...]