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Ecotones between tropical forests and lakes compose an ecosystem interconnection with a high abundance of terrestrial invertebrates, which represent an outstanding resource for the aquatic fauna. However, there is still little quantitative information on tropical forest contribution in terms of invertebrate inputs into lacustrine systems and the factors controlling this flux.To quantify the terrestrial invertebrate contribution into tropical lakes, we selected six lakes located in the Atlantic rainforest, south‐eastern Brazil, and used pan traps placed in the lakeshore. We focused on total abundance, biomass, and richness of insect orders. To assess the influence of forest and lake morphometry on terrestrial invertebrate inputs into lakes, we measured the forest–lake distance and considered the morphometric characteristics of each lake.Distance from forest negatively affected the invertebrate biomass reaching the lakes. The dissimilarity across different ecotones also increased with distance from the forest. Perimeter‐to‐area ratio negatively affected the invertebrate abundance, suggesting that more dendritic lakes receive more invertebrates from the forest.We estimated that annually, on average 21 tons of terrestrial invertebrates fall into the studied lakes, representing a massive food resource for the aquatic ecosystem. Hence, if the distance from the forest increases due, for instance, to severe drought or deforestation, it will create an herbaceous environment unable to provide such a quantity of insects to the water ecosystems, compromising aquatic and terrestrial trophic webs dynamics. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the relative importance of abiotic factors and biotic resistance (expressed as species richness of native macroinvertebrates), through a correlative niche-based model, to explain the abundance of the non-native mollusk Melanoides tuberculata. A total of 478 sites were sampled in six reservoirs in a Brazilian semi-arid region in June, September, December (2014) and March (2015). A niche-based model (BRT's), which included all tested predictor variables explained 41.7% total variation in M. tuberculata abundance. Water depth had the highest relative importance (19.0% of relative contribution) followed by temperature (17.2%) and sediment organic matter content (15.4%). The native macroinvertebrate richness explained only 8.0%, evidencing the smaller role of biotic resistance in explaining M. tuberculata abundance. Our results suggest that factors associated with the extent of species' niches are more important and can determine the multiple invasion processes of this mollusk, especially in terms of population growth and spread. The low explanatory power of biotic resistance on the abundance and distribution of the invasive mollusk may not necessarily indicate a lack of resistance by the native community, and M. tuberculata is not widespread enough to occupy the total potential range. [ABSTRACT FROM AUTHOR]