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Copyright of Boletín de la Asociación Española de Entomología is the property of Asociacion Espanola de Entomologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tropical peat swamp forests are major global carbon (C) stores highly vulnerable to human intervention. In Peruvian Amazonia, palm swamps, the prevalent peat ecosystem, have been severely degraded through recurrent cutting of Mauritia flexuosa palms for fruit harvesting. While this can transform these C sinks into significant sources, the magnitude of C fluxes in natural and disturbed conditions remains unknown. Here, we estimated emissions from degradation along a gradient comprising undegraded (Intact), moderately degraded (mDeg) and heavily degraded (hDeg) palm swamps. C stock changes above- and below-ground were calculated from biomass inventories and peat C budgets resulting from the balance of C outputs (heterotrophic soil respiration (Rh), dissolved C exports), C inputs (litterfall, root mortality) and soil CH4 emissions. Fluxes spatiotemporal dynamics were monitored (bi)monthly over 1–3 years. The peat budgets (Mg C ha−1 year−1) revealed that medium degradation reduced by 88% the soil sink capacity (from − 1.6 ± 1.3 to − 0.2 ± 0.8 at the Intact and mDeg sites) while high degradation turned the soil into a high source (6.2 ± 0.7 at the hDeg site). Differences stemmed from degradation-induced increased Rh (5.9 ± 0.3, 6.2 ± 0.3, and 9.0 ± 0.3 Mg C ha−1 year−1 at the Intact, mDeg, and hDeg sites) and decreased C inputs (8.3 ± 1.3, 7.1 ± 0.8, and 3.6 ± 0.7 Mg C ha−1 year−1 at the same sites). The large total loss rates (6.4 ± 3.8, 15.7 ± 3.8 Mg C ha−1 year−1 under medium and high degradation), originating predominantly from biomass changes call for sustainable management of these peatlands. [ABSTRACT FROM AUTHOR]

We investigated the distribution patterns of galling insects in veredas with varying degrees of drying in the Brazilian Cerrado. We tested if the insect gall diversity is higher in degraded veredas (dry veredas) compared to preserved (wet veredas) ones, as predicted by the hygrothermal stress hypothesis. Additionally, we also tested whether the composition of galling insects varied along the veredas and if species richness and abundance of galling insects are higher in the upstream zone of the veredas. In total, we recorded 99 species of galling insects, distributed across 54 plant species and 24 botanical families. We found that galling species richness was high in degraded veredas compared to preserved ones, while the abundance of galling insects was higher in preserved veredas than in degraded ones. When examining the different zones along the veredas, we observed variations in the richness and abundance of galling insects in preserved veredas. Specifically, the galling insect richness was higher in the upstream and middle zones compared to the downstream zone, while the abundance of galling insects was higher in the middle zone compared to the upstream zone. However, in the degraded veredas, there were no significant differences in galling species richness and abundance among the zones studied. The composition of galling insect species differed significantly between degraded and preserved veredas, with a higher faunal similarity observed in preserved veredas for both the downstream and upstream zones compared to degraded veredas (upstream zone). Our results indicate a preference of galling insects for more hygrothermally stressed environments, such as dry veredas and upstream zones of wet veredas. [ABSTRACT FROM AUTHOR]

Dominance of neotropical tree communities by a few species is widely documented, but dominant trees show a variety of distributional patterns still poorly understood. Here, we used 503 forest inventory plots (93,719 individuals ≥2.5 cm diameter, 2609 species) to explore the relationships between local abundance, regional frequency and spatial aggregation of dominant species in four main habitat types in western Amazonia. Although the abundance-occupancy relationship is positive for the full dataset, we found that among dominant Amazonian tree species, there is a strong negative relationship between local abundance and regional frequency and/or spatial aggregation across habitat types. Our findings suggest an ecological trade-off whereby dominant species can be locally abundant (local dominants) or regionally widespread (widespread dominants), but rarely both (oligarchs). Given the importance of dominant species as drivers of diversity and ecosystem functioning, unravelling different dominance patterns is a research priority to direct conservation efforts in Amazonian forests., (© 2023 The Authors. Ecology Letters published by John Wiley & Sons Ltd.)