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Chronic anthropogenic disturbances and climate change have been recognized as drivers of biological reorganization across human‐modified tropical landscapes, also negatively affecting the reproductive output of some plant species. Here, we investigated to what extent these drivers affect the reproductive output of Cenostigma microphyllum, a disturbance‐adapted tree species endemic to the Caatinga dry forest. The production of flowers/inflorescence, fruits and seeds was estimated for 105 plants (≥3 cm diameter at soil height) across 11 forest stands (20 × 50 m each), covering gradients of chronic disturbances (e.g. goat and livestock herbivory; wood extraction; and removal of non‐timber forest products) and aridity at the Catimbau National Park. We documented that when the drivers were analysed in isolation, the fruit‐set was positively associated with increased wood extraction, and the fruit‐set and total number of seeds/plots were reduced under increasing aridity. We also verified a complex interaction between wood extraction and aridity emerged. In forest stands, the combination of high levels of aridity and wood extraction leads to a decrease in the fruit‐set and total number of seeds/plots. Conversely, the fruit‐set and total number of seeds/plots increased in stands exposed to lower aridity but high levels of wood extraction. Our results suggest that chronic disturbances and aridity affect plant fitness in a complex way including both negative and positive effects on attributes related to plant reproductive performance, which could result in both proliferation and population decline in the same landscape. Although C. microphyllum benefits from anthropogenic disturbances and is considered a disturbance‐adapted species, it apparently does not benefit from increases in aridity, which is an expected future scenario for the Caatinga dry forest. [ABSTRACT FROM AUTHOR]

The ability of dry forests to deliver ecosystem services of both local and global relevance depends on the capacity of those forests to recover from constant disturbances in human-modified landscapes. Here we examine the effects posed by biomass, chronic human disturbances and aridity on the recovery of reproductive functional diversity by edible fruit plant assemblages following slash-and-burn agriculture in a Caatinga dry forest, in northeastern Brazil. The edible fruit plant assemblages were described across 24 forest stands, including regenerating stands of varying age (4 to 50 yr old) and old-growth stands, adopting a large set of reproductive traits as floral sizes, reproductive systems, and pollination systems. Such a chronosequence covered a gradient relative to aboveground biomass, aridity, and chronic anthropogenic disturbances (CAD). We observed that edible fruit plant assemblages across both regenerating and old-growth forest stands exhibited similar taxonomic diversity scores. This pattern is also figured in the recovery of reproductive traits, which is relatively fast as regenerating forest scores are generally similar or higher to those in old-growth forests. Generally, regenerating forest stands support more specialized reproductive traits and strategies than old-growth forest stands [e.g., edible fruit plants with very large flowers (>30 mm), specialized pollination systems, large fruits (>1.5 ≤3.0 mm), and medium-sized seeds (>0.6 ≤1.5 cm). However, the functional diversity of specialist reproductive traits decreased with increases in the levels of biomass and aridity, isolated, but was also impacted by the interactive effect. Considering the effects of biomass, CAD or aridity individually, we observed that biomass itself was responsible for most of the effects (42.8%), while 52.3% of the reproductive traits were negatively affected by CAD or aridity, which seems to be a major force against the recovery. [Display omitted] • Secondary forests harbor similar abundance of edible fruit plants as mature forests. • Aridity reduces the species richness of edible fruit plant assemblages. • Secondary forests harbor more specialized traits and strategies than mature forests. • The successional trajectory goes from specialized to generalist traits. • Aridity act as a strong environmental filter against regeneration. [ABSTRACT FROM AUTHOR]

• Chronic anthropogenic disturbances and aridity pose negative or positive effects on reproductive traits of edible fruit assemblages in a Caatinga dry forest. • Seventy-five percent of the edible fruit species have specialized reproductive strategies that are negatively affected by chronic disturbances and/or aridity. • Chronic disturbances and aridity negatively affect specialized reproductive traits and strategies of edible fruit assemblages. • Aridity mediates the effects of chronic disturbances mainly on the abundance of specialized reproductive strategies of edible fruit assemblages. • The functional diversity of specialized reproductive strategies of edible fruit assemblages was negatively affected by aridity. Chronic anthropogenic disturbances and climate change are the main threats to biodiversity, acting as potential drivers of assembly reorganization in human-modified tropical landscapes. We aimed to understand how the reproductive traits of edible fruit plant assemblages respond to chronic disturbances and aridity in the Caatinga, a dry forest in northeastern Brazil housing a human population that greatly depends on natural resources for subsistence and is threatened by increasing aridity. The study was carried out across 20 permanent plots of Caatinga, covering gradients of chronic disturbances (livestock grazing, wood extraction and non-timber product exploitation) and aridity (1051 mm to 664 mm). We registered 24 native plant species with fruits that are edible for humans, which were classified according to their flowering/fruiting pattern, floral size and reward, sexual and reproductive systems, pollination systems, and fruit types. They were also grouped into two categories of reproductive strategies (generalists and specialists). We documented that chronic disturbances and aridity pose more negative than positive effects on the reproductive traits of edible fruit plants in terms of trait richness (negative: 29% of the traits; positive: 3.2%) and abundance (negative: 19.3%; positive: 3.2%). In general, we observed that 79.2% of the studied species had at least one reproductive trait that was negatively reduced by increased chronic disturbance and/or aridity in terms of trait richness and abundance. Overall, 75% of the edible fruit species have specialized reproductive strategies that were negatively affected by chronic disturbances and/or aridity. Specifically, individual or combined effects of chronic anthropogenic disturbances or aridity negatively impacted the richness and abundance of specialized reproductive traits such as supra-annual flowering and fruiting patterns and obligatory cross-pollinated edible fruit species. Also, in terms of richness, the reproductive functional diversity of specialized reproductive strategies was negatively affected by increasing aridity. Our findings indicate that in the expected future scenarios of increased land-use and climate change, the Caatinga could face a collapse in the offer of edible fruits to local human communities by impacting the provision of this ecosystem service. [ABSTRACT FROM AUTHOR]