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The Amazon Reef System (ARS) is one of the most important shallow and mesophotic reef ecosystems in the South Atlantic Ocean. The ARS consists mainly of extensive beds of calcareous algae interspersed by assemblages of octocorals and sponges. The enormous freshwater discharge from the Amazon River forms a plume along the extensive Amazon continental shelf, for which the hydroid community is still largely unknown. The aim of this study is to document the diversity and distribution of hydroids from the ARS, as well as to infer the influence of the plume on species composition in the different zones. Samples were collected at ninety-six stations between 15 and 240 m deep on the Amazon shelf. A total of 37 species were recorded in the studied area. Hydroid assemblages are richer in zones under lower river plume influence, and species composition differs significantly between zones with and without plume influence (PERMANOVA, p = 0.0025). The dissolved oxygen and nitrate ranges were the environmental variables significantly correlated with the hydroid distribution. This study is the first surveying the hydroid species composition and richness in the ARS, highlighting the presence of a typical reef biota and that further faunal studies in underexplored areas of the Atlantic should reveal the distribution of many poorly known hydroids species.

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Reference conditions are difficult to find in the Anthropocene but essential for effective biodiversity conservation. Aquatic ecosystems in the Andes-Amazon transition zone of Colombia are now at high risk due to expanded human activities after peace agreements in 2016 ended armed conflict because lands formerly controlled by FARC and other armed groups are now prone to agricultural and urban expansion. Particularly, expanding human land use may reduce fish diversity across the altitudinal gradient, especially in the premontane streams (i.e., <500 m a.s.l.) because lands are more amenable to human use than at greater altitudes. We evaluated fish α-diversity (measured as species richness, total abundance, and effective species number) and ß-diversity (spatial and temporal) in 12 sites over 8 years bracketing the end of armed conflict. All α-diversity and ß-diversity analyses were evaluated relative to categorical altitude (< or >500 m) and continuous altitude. Strong differences in fish community structure among sites occurred as a function of altitude. Fish communities exhibit altitudinal biodiversity gradients that are consistent in space and time, and that need to be accounted for conservation and management considerations. Our results provide a reference to identify short- and long-term changes due to impending human land use at a critical moment for the conservation of tropical fish diversity. Similar studies in other areas of the upper Amazon Basin are needed to evaluate effects of subsequent human activities on diversity patterns and our study area to compare to reference conditions reported here.

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Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream results. Understanding how best to fill existing gaps and account for biases is necessary to improve our current information most effectively. Two current main approaches for obtaining and improving data include (1) curation of biological collections, and (2) fieldwork. However, the comparative effectiveness of these approaches in improving biodiversity data remains little explored. We used the Flora de Bogotá project to study the magnitude of change in species richness, spatial coverage, and sample coverage of plant records based on curation versus fieldwork. The process of curation resulted in a decrease in species richness (synonym and error removal), but it significantly increased the number of records per species. Fieldwork contributed to a slight increase in species richness, via accumulation of new records. Additionally, curation led to increases in spatial coverage, species observed by locality, the number of plant records by species, and localities by species compared to fieldwork. Overall, curation was more efficient in producing new information compared to fieldwork, mainly because of the large number of records available in herbaria. We recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity, to identify bias and gaps at the regional scale that can then be targeted with fieldwork. The stepwise strategy would enable fieldwork to be planned more cost-effectively given the limited resources for biodiversity exploration and characterization.

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Since their discovery, rumen ciliates of domestic cattle have been reported from various geographic locations. However, until now there is only one taxonomic inventory of ciliates associated with Brazilian cattle. The present study aimed to assess the community composition, relative abundance, richness, and density of rumen ciliates in Brazilian cattle, whose feeding diets were supplemented with crescent urea levels. Across all treatments analyzed, one subclass, two orders, three families, 11 genera, and 31 species of ciliates were identified. The ciliate community composition and species richness varied among the four treatments used. However, the total ciliate density was not affected by the experimental diets. We described a new entodiniid morphotype, Entodinium caudatum m. orbonuclearis, and recorded Oligoisotricha bubali for the second time in Brazil.

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Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna—particularly insects—associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.

Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.

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Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the faunaparticularly insectsassociated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.

Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.

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Hass avocado fruit diseases are one of the main marketing constraints in Colombia. To identify and reveal the diversity of fungi associated with diseases in fruits and peduncles, symptomatic samples were collected from 67 farms in the 9 main Hass avocado-producing municipalities of the department of Cauca located in southwestern Colombia. A total of 237 monosporic isolates were obtained that were subjected to DNA extraction, amplification of the ITS region, sequencing and functional diversity analysis based on Hill numbers by municipality and altitude. The results indicated that the genera Pseudocercospora, Diaporthe, Colletotrichum, Neofusiococcum, Lasiodiplodia and Pestatoliopsis were associated with fruit diseases. The genus with the highest number of effective species was Colletotrichum. The ITS region revealed 100% identity of the species Pseudocercospora norchiensis, which was the first report of this pathogen in the crop. There was a greater richness and diversity of associated species in the three municipalities, revealing that the higher the altitude was, the lower the richness and diversity of fungi associated with fruit diseases. These results will provide a better understanding of the identification and diversity of pathogenic microorganisms present in avocado production systems in this region of Colombia.

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Amphibians are the most threatened species-rich vertebrate group, with species extinctions and population declines occurring globally, even in protected and seemingly pristine habitats. These 'enigmatic declines' are generated by climate change and infectious diseases. However, the consequences of these declines are undocumented as no baseline ecological data exists for most affected areas. Like other neotropical countries, Costa Rica, including Área de Conservación Guanacaste (ACG) in north-western Costa Rica, experienced rapid amphibian population declines and apparent extinctions during the past three decades. To delineate amphibian diversity patterns within ACG, a large-scale comparison of multiple sites and habitats was conducted. Distance and time constrained visual encounter surveys characterised species richness at five sites-Murciélago (dry forest), Santa Rosa (dry forest), Maritza (mid-elevation dry-rain forest intersect), San Gerardo (rainforest) and Cacao (cloud forest). Furthermore, species-richness patterns for Cacao were compared with historic data from 1987-8, before amphibians declined in the area. Rainforests had the highest species richness, with triple the species of their dry forest counterparts. A decline of 45% (20 to 11 species) in amphibian species richness was encountered when comparing historic and contemporary data for Cacao. Conservation efforts sometimes focus on increasing the resilience of protected areas, by increasing their range of ecosystems. In this sense ACG is unique containing many tropical ecosystems compressed in a small geographic space, all protected and recognised as a UNESCO world heritage site. It thus provides an extraordinary platform to understand changes, past and present, and the resilience of tropical ecosystems and assemblages, or lack thereof, to climate change.

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The food chain length represents how much energy reaches different trophic levels in food webs. Environmental changes derived from human activities have the potential to affect chain length. We explore how habitat area and edges affect chain length through: (1) a bottom-up effect of abundance ('pyramid hypothesis'); (2) the truncation of the highest trophic level ('trophic-rank hypothesis'); and (3) changes in species connectivity patterns ('connectivity hypothesis'). We built plant-leaf miner-parasitoid food webs in 19 remnants of a fragmented Chaco forest from central Argentina. On each remnant, we constructed food webs from different locations at the forest interior and edges. For each food web, we registered the abundance of species, the species richness of each trophic level, estimated the connectivity of their networks, and the average food chain length. We used structural equation models to evaluate the direct and indirect effects of habitat area and edge/interior location on food chain length mediated by species richness, abundance and connectivity. We found no direct effects of habitat area on chain length but chains were longer at forest edges than at their interior. The three mechanisms were supported by our results, although they showed different strengths. First, we found that the interior favours a bottom-up abundance effect from herbivores to parasitoids that positively affected chain length; second, we found that the forest area positively affects plant richness, which has a strong effect on the number of resources used by consumers, with a positive effect on chain length. Third, the remnant area and interior position favoured plant richness with a negative effect on the abundance of parasitoids, which had a positive effect on chain length. In general, the strongest effects on chain length were detected through changes in abundance rather than species richness although abundance was less affected by habitat fragmentation. We evaluated for the first time the effects of human-driven habitat fragmentation on the length of trophic chains in highly diverse plant-herbivore-parasitoid networks. Despite the loss of species, small habitat fragments and edges embedded in the agricultural matrix can support interaction networks, making them conservation targets in managed landscapes.

El largo de cadenas tróficas representa cuanta energía alcanza diferentes niveles tróficos en redes tróficas. Los cambios ambientales producto de las actividades humanas tienen el potencial de afectar el largo de las cadenas tróficas. Exploramos como el área de hábitat y los bordes afectan el largo de cadenas tróficas a través de: (1) un efecto ascendente de la abundancia ('hipótesis pirámide'); (2) el truncamiento del nivel trófico superior ('hipótesis de ranking trófico'); y (3) cambios en los patrones de conectividad ('hipótesis de conectividad'). Construimos redes tróficas entre plantas-minadores de hoja-parasitoides en 19 remanentes de bosque Chaqueño serrano altamente fragmentado en el centro de Argentina. Para cada remanente construimos redes tróficas en distintas ubicaciones en el borde e interior del bosque. Para cada red trófica registramos la abundancia media de las especies, la riqueza de cada nivel trófico, estimamos la conectividad de las redes y el largo de cadenas tróficas promedio. Utilizamos modelos de ecuaciones estructurales para evaluar los efectos directos e indirectos del área y la ubicación borde/interior sobre el largo de cadenas tróficas mediado por la riqueza de especies, la abundancia y la conectividad. No encontramos efectos directos del área de hábitat sobre el largo de cadenas, pero las cadenas fueron más largas en los bordes que en el interior. Los tres mecanismos propuestos fueron apoyados por los resultados, pero mostraron distinta fuerza. Primero, encontramos que el interior de los bosques favorece los efectos ascendentes de la abundancia desde los herbívoros a los parasitoides lo que afectó positivamente al largo de las cadenas; segundo, encontramos que el área de bosque afectó positivamente a la riqueza de especies, lo que tuvo un efecto positivo en el largo de cadenas. Tercero, el área de bosque remanente y la ubicación en el interior favorecieron la riqueza de plantas, influyendo negativamente en la abundancia de parasitoides lo que tuvo un efecto positivo en el largo de cadenas. En general, los efectos más fuertes sobre el largo de cadenas se detectaron a través de cambios en la abundancia más que en la riqueza, aunque la abundancia fue menos afectada por la fragmentación del hábitat que la riqueza de especies. En este estudio evaluamos por primera vez los efectos de la fragmentación del hábitat por causas humanas sobre el largo de cadenas tróficas en redes tróficas altamente diversas de plantas, herbívoros y parasitoides. A pesar de la pérdida de especies, los fragmentos pequeños y los bordes de bosque inmersos en una matriz agrícola pueden sostener redes de interacciones, convirtiéndolos en objetivos de conservación en paisajes manejados.

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RESUMEN Un total de 326 helmintos parásitos fueron recuperados de 94 especímenes de Halichoeres bivittatus (Pisces: Labridae) en dos sitios de la zona arrecifal en los límites del Parque Nacional Sistema Arrecifal Veracruzano, Veracruz, México, el suroeste del Golfo de México: Punta Gorda (n = 51) y Mata de Uva (n = 43). Los peces fueron capturados entre mayo y septiembre de 2001. Cada muestra se analizó a nivel de comunidad componente e infracomunidad. Tres especies de helmintos se localizaron en intestino: Nicolla halichoeri (Digenea) considerándose nuevo registro de localidad, Procamallanus (Spirocamallanus) garnotus (Nematoda) es nuevo registro de hospedero, y las larvas de Tetraphyllidea gen. sp. (Cestoda) fueron los parásitos con mayor prevalencia e intensidad promedio para cada sitio. La riqueza de especies para ambos sitios fue de S = 3 y el índice de diversidad de Shannon-Wiener (Punta Gorda, H'= 0,42; Mata de Uva, H'= 0,49) fueron inferiores a los registrados para las comunidades hospedero-parásito de lábridos y de hospederos de la localidad. No hubo correlación entre el número total de especies o el número total de helmintos con respecto a la longitud total o el peso del hospedero. El análisis de las curvas de especies acumuladas para la comunidad componente sugirió, que el inventario de especies de helmintos estaba casi completo para ambos sitios. La abundancia de larvas del céstodo ubica a H. bivittatus como hospedero intermediario del parásito.

ABSTRACT A total of 326 parasitic helminths were obtained from 94 specimens of Halichoeres bivittatus (Pisces: Labridae) at two sites in the reef zone at the limits of the Veracruz Reef System National Park, Veracruz, Mexico, southwestern Gulf of Mexico: Punta Gorda (n = 51) and Mata de Uva (n = 43). Fish were caught from May to September 2001. Each sample was examined at the levels of the component community and infracommunity. Three parasitic helminth species were found in intestines: Nicolla halichoeri (Digenea: Plagiorchiida: Opecoelidae) is a new geographic record, Procamallanus (Spirocamallanus) garnotus (Nematoda) is a new host record, and larvae of Tetraphyllidea gen. sp. (Cestoda) were the parasites with the highest prevalence and the average intensity at both sites. Species richness (S = 3) and the Shannon-Wiener diversity index (H'= 0,42; 0,49) were lower than those previously estimated for the labrid host-parasite community in the study area. No correlations between the total number of species or the total number of helminths and the total length or weight of the host were observed. An analysis of the accumulated curve for the component community suggested that the inventory of helminth species was almost complete for both sites. The abundance of cestode larvae infers H. bivittatus is an intermediate host of the parasite.

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For more than three decades, major efforts in sampling and analyzing tree diversity in South America have focused almost exclusively on trees with stems of at least 10 and 2.5 cm diameter, showing highest species diversity in the wetter western and northern Amazon forests. By contrast, little attention has been paid to patterns and drivers of diversity in the largest canopy and emergent trees, which is surprising given these have dominant ecological functions. Here, we use a machine learning approach to quantify the importance of environmental factors and apply it to generate spatial predictions of the species diversity of all trees (dbh ≥ 10 cm) and for very large trees (dbh ≥ 70 cm) using data from 243 forest plots (108,450 trees and 2832 species) distributed across different forest types and biogeographic regions of the Brazilian Amazon. The diversity of large trees and of all trees was significantly associated with three environmental factors, but in contrasting ways across regions and forest types. Environmental variables associated with disturbances, for example, the lightning flash rate and wind speed, as well as the fraction of photosynthetically active radiation, tend to govern the diversity of large trees. Upland rainforests in the Guiana Shield and Roraima regions had a high diversity of large trees. By contrast, variables associated with resources tend to govern tree diversity in general. Places such as the province of Imeri and the northern portion of the province of Madeira stand out for their high diversity of species in general. Climatic and topographic stability and functional adaptation mechanisms promote ideal conditions for species diversity. Finally, we mapped general patterns of tree species diversity in the Brazilian Amazon, which differ substantially depending on size class.

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Fruit flies (Diptera: Tephritoidea) are the main pests over important fruits and vegetables. In this research was evaluated the tritrophic interactions of fruit flies and their parasitoids occurring in native fruits in the Chaco Biome. Fruit sampling was carried out monthly in three areas of vegetation communities in Chaco Biome: Forested Steppic Savanna, Wooded Steppic Savanna, Park Steppic Savanna, Porto Murtinho-MS, Brazil, from April 3, 2017, to November 16, 2018 (totaling 20 samples). Fruits of 33 plant species were examined for fruit flies and parasitoids from these three Chaco locations. Sixteen species of fruit plants were infested by 11 species of fruit flies: five species of Anastrepha Schiner (Tephritidae): Anastrepha fraterculus (Wiedemann), Anastrepha obliqua (Macquart), Anastrepha sororcula Zucchi, Anastrepha turpiniae Stone, Anastrepha zenildae Zucchi, and six of Neosilba McAlpine (Lonchaeidae): Neosilba bifida Strikis and Prado, Neosilba certa (Walker), Neosilba glaberrima (Wiedemann), Neosilba inesperata Strikis and Prado, Neosilba pendula (Bezzi), Neosilba zadolicha McAlpine and Steyskal. Three species of parasitoids: Doryctobracon areolatus (Szepliget) and Utetes anastrephae (Viereck) (Braconidae) parasitized Anastrepha spp., and Aganaspis pelleranoi (Figitidae) parasitized Neosilba spp. All fruit flies and parasitoid species reported here are new records for the Chaco Biome. Furthermore, the following trophic associations are new records worldwide: Anastrepha obliqua in Sideroxylon obtusifolium; Anastrepha zenildae, Neosilba inesperata, and Neosilba zadolicha in Eugenia myrcianthes; Anastrepha fraterculus, Anastrepha sororcula, Neosilba pendula, and Neosilba inesperata in Campomanesia adamantium; Anastrepha spp. in Garcinia gardneriana and Agonandra brasiliensis.

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Amazonian forests function as biomass and biodiversity reservoirs, contributing to climate change mitigation. While they continuously experience disturbance, the effect that disturbances have on biomass and biodiversity over time has not yet been assessed at a large scale. Here, we evaluate the degree of recent forest disturbance in Peruvian Amazonia and the effects that disturbance, environmental conditions and human use have on biomass and biodiversity in disturbed forests. We integrate tree-level data on aboveground biomass (AGB) and species richness from 1840 forest plots from Peru's National Forest Inventory with remotely sensed monitoring of forest change dynamics, based on disturbances detected from Landsat-derived Normalized Difference Moisture Index time series. Our results show a clear negative effect of disturbance intensity tree species richness. This effect was also observed on AGB and species richness recovery values towards undisturbed levels, as well as on the recovery of species composition towards undisturbed levels. Time since disturbance had a larger effect on AGB than on species richness. While time since disturbance has a positive effect on AGB, unexpectedly we found a small negative effect of time since disturbance on species richness. We estimate that roughly 15% of Peruvian Amazonian forests have experienced disturbance at least once since 1984, and that, following disturbance, have been increasing in AGB at a rate of 4.7 Mg ha-1 year-1 during the first 20 years. Furthermore, the positive effect of surrounding forest cover was evident for both AGB and its recovery towards undisturbed levels, as well as for species richness. There was a negative effect of forest accessibility on the recovery of species composition towards undisturbed levels. Moving forward, we recommend that forest-based climate change mitigation endeavours consider forest disturbance through the integration of forest inventory data with remote sensing methods.

Los bosques amazónicos son reservorios y sumideros de carbono, contribuyendo a la mitigación del cambio climático. Si bien experimentan perturbaciones, el efecto de estas en la biomasa y biodiversidad a través del tiempo no ha sido evaluado a gran escala. En este estudio, evaluamos el grado de perturbación forestal reciente en la Amazonía peruana y los efectos de las perturbaciones, condiciones ambientales y actividad antrópica sobre la biomasa y la biodiversidad en bosques perturbados. Los datos de biomasa aérea y riqueza de especies forestales provenientes de 1,840 subparcelas del Inventario Nacional Forestal y de Fauna Silvestre (INFFS) se analizaron en conjunto con la información de detección de cambios de cobertura forestal derivadas de perturbaciones detectadas a partir de series de tiempo de índices de diferencia de humedad normalizados (NDMI) a partir de imágenes Landsat. Nuestros resultados muestran un claro efecto negativo de la intensidad de las perturbaciones sobre la riqueza de especies arbóreas. Este efecto también fue observado en los valores de recuperación de biomasa aérea y riqueza de especies arbóreas hacia niveles no perturbados, así como en la recuperación de la composición florística. El tiempo transcurrido desde la perturbación tuvo un efecto mayor sobre la biomasa aérea que sobre la riqueza de especies. Mientras el tiempo desde una perturbación forestal tuvo un efecto positivo sobre la biomasa área, se observó un pequeño efecto negativo sobre la riqueza de especies. Estimamos que aproximadamente el 15% de los bosques en la Amazonía peruana han experimentado una perturbación al menos una vez desde 1984, y que, tras esta, han aumentado en biomasa aérea en una tasa de 4.7 Mg ha−1 año−1 durante los primeros 20 años posteriores al evento de perturbación. Además, el efecto positivo de la cubierta forestal circundante fue evidente tanto para la biomasa aérea como para su recuperación hacia niveles no perturbados, así como para los valores de riqueza de especies. La accesibilidad a bosques tuvo un efecto negativo en la recuperación de la composición de especies hacia niveles no perturbados. Recomendamos que los esfuerzos de mitigación de cambio climático basados en bosques tengan en cuenta las perturbaciones forestales mediante el análisis integrado de información de inventarios forestales con métodos de teledetección.

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The kinetic hypothesis of biodiversity proposes that temperature is the main driver of variation in species richness, given its exponential effect on biological activity and, potentially, on rates of diversification. However, limited support for this hypothesis has been found to date. I tested the fit of this model to the variation of tree-species richness along a continuous latitudinal gradient in the Americas. I found that the kinetic hypothesis accurately predicts the upper bound of the relationship between the inverse of mean annual temperature (1/kT) and the natural logarithm of species richness, at a broad scale. In addition, I found that water availability and the number of days with freezing temperatures explain part of the residual variation of the upper bound model. The finding of the model fitting on the upper bound rather than on the mean values suggest that the kinetic hypothesis is modeling the variation of the potential maximum species richness per unit of temperature. Likewise, the distribution of the residuals of the upper bound model in function of the number of days with freezing temperatures suggest the importance of environmental thresholds rather than gradual variation driving the observable variation in species richness.

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This data paper summarizes the data of a first survey of terrestrial ferns at Mashpi Biodiversity Reserve, an Ecuadorian Chocó forest relict, one of the most biodiverse areas in the world. We established 10 permanent plots of 400 m2 distributed in two elevational levels (800 and 1000 m a.s.l.) to register all species per plot and the abundance per species. In addition, we measured two morphological leaf functional traits of the species. We include a file with three tables, the first one includes a species list with scientific names and vouchers. The second one includes the abundance of each species per plot. The third one contains measurements of the leaf length and leaf thickness of several leaf samples of 28 species, representing the leaf functional traits of the species. This article also includes a table with coordinates and elevations of the plots and five figures with information about the number of genus and species per family, geographic location of plots and, the methodology for data collection. These data can be useful for plant ecologists to assess future changes of fern species composition and leaf functional traits of ferns caused by climate change and other threats at the study area.

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The Caatinga is an exclusively Brazilian biome, and is the largest and most biodiverse Seasonal Tropical Dry Forest in the world. Despite that, the mammalian fauna, especially small mammals, is the least studied of all Brazilian biomes. In order to fill gaps and provide detailed information on small mammals (Didelphimorphia, Rodentia) in the Caatinga biome, we compiled reliable records focusing on richness, composition and some biometric data. These records came from mammal collections, papers, theses, books, and unpublished data, prioritizing records with vouchers housed in scientific collections. We compiled a total of 3133 records from 816 locations, resulting in a richness of 47 native species (12 marsupials and 35 rodents, plus three exotic rodents, Rattus rattus, Rattus norvegicus, and Mus musculus). This dataset includes records of three new species for the biome and its transition zone: the rodents Calomys mattevii, Holochilus oxe, and Nectomys squamipes. Of the total number of records, 1808 (57.71%) are from consulting activities, 95 (3.03%) are from zoonoses studies and 104 (3.32%) are from the National Plague Service (SNP). All nine Brazilian states with territory in the Caatinga have sampling data for small mammals, but the number of records and localities are unevenly distributed, with the state of Rio Grande do Norte having the lowest number of records and locations sampled. Our dataset is the first of its kind for the Caatinga biome and has considerable potential value for studies of habitat use, landscape ecology, macroecology, biogeography, and conservation. There are no copyright restrictions on the data. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

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Species invasion is a major threat to marine biodiversity and function; thus, studying the effects of recently reported exotic species is extremely important. Several soft coral species (Alcyonacea) have invaded the Atlantic Ocean but their effects are poorly known. Here, we investigated the effects of the invasive species Sarcothelia sp. (Alcyonacea, Xeniidae) on native benthic shallow reef communities in Brazil. We hypothesized that increasing Sarcothelia sp. abundance would be related to species richness decreases and native community structure changes. Multivariate analysis showed significant dissimilarity between invaded (high Sarcothelia sp. abundance) and non-invaded areas (high abundance of the octocoral Neospongodes atlantica and zoantharians). The invaded area showed less species composition variability (i.e., homogenization) than non-invaded ones. Within the invaded area we observed that Sarcothelia sp. abundance reduced species richness. The lowest native benthic richness (10 taxa) was observed in a transect with the highest invader cover, while the transect with the lowest Sarcothelia sp. cover presented 26 native taxa. These findings are likely related to the invasive novel functional traits, i.e., invader growth form and allelochemicals. A clear inverse abundance pattern between invasive Sarcothelia sp. and N. atlantica, indicated an intense competition between octocorals. Our study showed remarkable evidence of negative impacts of invasive soft corals on reef biodiversity. There is an urgent need for experiments evaluating changes in different ecological processes and to implement management actions.

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Given the importance of species diversity as a tool for assessing recovery during forest regeneration and active restoration, robust approaches for assessing changes in tree species diversity over time are urgently needed. We assessed changes in tree species diversity during natural regeneration over 12-20 years in eight 1-ha monitoring plots in NE Costa Rica, six second-growth forests and two old-growth reference forests. We used diversity profiles to show successional trajectories in measures of observed, asymptotic and standardized tree diversity and evenness as well as sample completeness. We randomly subsampled 1-ha plot data to evaluate how well smaller spatial subsamples would have captured temporal trajectories. Annual surveys in eight 1-ha plots were missing substantial numbers of rare or infrequent species. Older second-growth sites showed consistent declines in tree diversity, whereas younger sites showed fluctuating patterns or increases. Subsample areas of 0.5 ha or greater were sufficient to infer the diversity of abundant species, but smaller subsamples failed to capture temporal trajectories of species richness and yielded positively biased estimates of evenness. In tropical forest regions with high levels of diversity, species diversity from small sample plots should be assessed using methods that incorporate abundance information and that standardize for sample coverage. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

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Invasive plants are a prominent threat to ecosystems and economies worldwide. Knowing the identity of invasive plants is critical for preventing their introduction and spread. Yet several lines of evidence, including spatial and taxonomic biases in reporting and the ongoing emergence of new invasives, suggest that we are missing basic information about the identity of invasive plants. Using a database of invasive plants reported in the peer-reviewed literature between 1959 and 2020, we examined trends in the accumulation of new invasive plants over time and estimated the size of the current pool of invasive plants both continentally and globally. The number of new invasive plants continues to increase exponentially over time, showing no sign of saturation, even in the best studied regions. Moreover, a sample-size based rarefaction-extrapolation curve of reported taxa suggests that what is documented in the current literature (3008 taxa) only captures 64% of the likely number of invasive plants globally (4721 taxa ± 132 SE). These estimates varied continentally; less than half of invasive plant taxa have likely been identified in Oceania and Central and South Americas. Studies that included multiple invasive plants (e.g., floristic studies) were much more efficient at adding new taxa to our global understanding of what is invasive (identifying 4.2 times more new taxa than single-taxon studies). With more potential invaders arriving every day, this analysis highlights a critical gap in our knowledge of the current invasive plant pool. Expanding invasion science to better encompass understudied geographic areas and increasing the numbers of floristic surveys would greatly improve our ability to accurately and efficiently identify what taxa are invasive. Preventing invasive plant introductions is incumbent upon knowing the identity of invasive plants. Thus, large knowledge gaps remain in invasion ecology that hinder efforts to proactively prevent and manage invasive plants.

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ABSTRACT The SISBIOTA-BRASIL was a three-year multimillion-dollar research program of the Brazilian government to document plants and animals in endangered/understudied areas and biomes in Brazil. Distributional patterns and the historical events that generated them are extensively unknown regarding Brazilian fauna and flora. This deficiency hinders the development of conservation policies and the understanding of evolutionary processes. Conservation decisions depend on precise knowledge of the taxonomy and geographic distribution of species. Given such a premise, we proposed to research the diversity of Diptera of the Brazilian western arc of Amazon, Cerrado, and Pantanal in the states of Mato Grosso, Mato Grosso do Sul, and Rondônia. Three important biomes of the South American continent characterize these Brazilian states: Amazon forest, Cerrado (Brazilian Savannah), and Pantanal. Besides their ecological relevance, these biomes historically lack intensive entomological surveys. Therefore, they are much underrepresented in the Brazilian natural history collections and in the scientific literature, which is further aggravated by the fact that these areas are being exponentially and rapidly converted to commercial lands. Our project involved over 90 collaborators from 24 different Brazilian institutions and one from Colombia among researchers, postdocs, graduate and undergraduate students, and technicians. We processed and analyzed nearly 300,000 specimens from ~60 families of Diptera collected with a large variety of methods in the sampled areas. Here, we provide a detailed overview of the genera and species diversity of 41 families treated. Our results point to a total of 2,130 species and 514 genera compiled and identified for the three states altogether, with an increase of 41% and 29% in the numbers of species and genera known for the three states combined, respectively. Overall, the 10 most species-rich families were Tachinidae, Cecidomyiidae, Tabanidae, Psychodidae, Sarcophagidae, Stratiomyidae, Bombyliidae, Syrphidae, Tephritidae, and Asilidae. The 10 most diverse in the number of genera were Tachinidae, Stratiomyidae, Asilidae, Mycetophilidae, Syrphidae, Tabanidae, Muscidae, Dolichopodidae, Sarcophagidae, and Chloropidae. So far, 111 scientific papers were published regarding taxonomic, phylogenetic, and biogeographical aspects of the studied families, with the description of 101 new species and three new genera. We expect that additional publications will result from this investigation because several specimens are now curated and being researched by specialists.