Riparian ecosystems are suffering anthropogenic threats that reduce biodiversity and undermine ecosystem services. However, there is a great deal of uncertainty about the way species composition of assemblages is related to ecosystem function, especially in a landscape fragmentation context.Here, we assess the impact of habitat loss and disturbance on Functional Diversity (FD) components Functional Redundancy (FRed), Functional Evenness (FEve), and Functional Richness (FRic) of riparian forest bird assemblages to evaluate (a) how FD components respond to riparian forest width reduction and vegetation disturbance; (b) the existence of thresholds within these relationships; (c) which of the main birds diet guild (frugivores, insectivores, and omnivores) respond to such thresholds. We predict that FD components will be affected negatively and nonlinearly by riparian changes. However, guilds could have different responses due to differences of species sensitivity to fragmentation and disturbance. We expect to find thresholds in FD responses, because fragmentation and disturbance drive loss of specific FD components.Our results show that FRed and FEve were linearly affected by width and disturbance of riparian habitats, respectively. FRed was significantly lower in riparian forests assemblages below 400 m wide, and FEve was significantly higher above 60% disturbance. These responses of FD were also followed to the decline in insectivores and frugivores richness in riparian forests most affected by these changes.Consequently, our study suggests communities do not tolerate reduction in riparian forest width or disturbance intensification without negative impact on FD, and this becomes more critical for riparian area <400‐m wide or with more than 60% disturbance. This minimum riparian width required to maintain FRed is greater than the minimum width required for riparian forests by Brazilian law. Thus, it is important to consider mechanisms to expand riparian habitats and reduce the disturbance intensity in riparian forests so that riparian bird community FD may be effectively conserved.

Identifying deforested areas with high potential for natural forest recovery can be used as an aid for ecological restoration projects at large-scale. However, accurate predictions that infer the resilience (i.e. recovery rate after deforestation) and stability (i.e. the ability of the ecosystem to maintain its functions) of early second-growth forests are scarce at a regional scale. Here, we investigated the effect of climate, soil and topography on the resilience and stability of 165 early second-growth forests throughout the Brazilian Atlantic Forest. We also built prediction maps of potential resilience and stability to identify where reforestation could be optimized in the early stages of forest succession. We assessed the resilience and stability through an interannual plant primary productivity time series using a normalized difference vegetation index. Our analysis reveals that resilience was mainly associated with isothermality (i.e. diurnal temperature oscillation relative to the annual temperature oscillation) and precipitation of the warmest quarter. In turn, stability was mainly associated with the probability of bedrock occurrence, annual precipitation and precipitation seasonality. The prediction maps show a spatial pattern in which potential resilience and stability increase from north to south of the Atlantic Forest. Forest restoration can be optimized in regions with high potential resilience and stability, such as an isolated area on the north coast in the Bahia state and the southern region. However, restoration may require active practices and management in regions with low potential for both ecosystem properties, such as the north inland in the Bahia and Minas Gerais states. This ecosystemic approach can help achieve Atlantic Forest restoration commitments.