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1.
Sci Rep ; 15(1): 3992, 2025 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-39893237

RESUMEN

Habitat degradation from human activities affects essential microhabitats, threatening ecological processes like foraging, mating, locomotion, predator evasion, and competition among reptiles. We assessed how microhabitat selection and body temperature of the endangered lizard Liolaemus cuyumhue respond to differences in vegetation composition and thermal conditions between a disturbed site and an undisturbed site impacted by oil and gas activities in Argentina. During five expeditions between September 2022 and March 2023, we searched for L. cuyumhue and collected data on body temperature, substrate and air temperatures, body mass, snout-vent length, sex, and habitat characteristics. We also measured operative temperatures and assessed vegetation cover and microhabitat availability at each site. Our results showed significant differences in microhabitat characteristics and selection between sites. The undisturbed site had higher vegetation and lower operative temperatures, while the disturbed site had higher temperatures and lower vegetation, especially in summer. Lizards at the disturbed site showed higher body temperatures, suggesting stressful thermal conditions, and preferred microhabitats with lower bare ground cover. Capturing lizards in the disturbed site required more effort than in the undisturbed site. This study emphasizes the impact of habitat disturbance on the thermal environment and behavior of L. cuyumhue. Conservation efforts should prioritize maintaining and restoring vegetation to support the species' thermoregulation needs, especially under global warming.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Lagartos , Estaciones del Año , Animales , Lagartos/fisiología , Argentina , Calor , Masculino , Femenino , Temperatura Corporal/fisiología , Especies en Peligro de Extinción
2.
Oecologia ; 207(2): 29, 2025 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-39893289

RESUMEN

Plant communities with higher species richness and phylogenetic diversity can increase the diversity of herbivores and their enemies through trophic interactions. However, whether these two features of plant communities have the same positive influence on other guilds through non-trophic mechanisms requires further exploration. Dung beetles represent an ideal system for testing such impacts, as they do not have a specialized trophic interaction with plants and are sensitive to changes in vegetation structure and the associated microclimate. We used a dataset of dung beetles collected from forest sites, restoration plots, and cattle pastures to (a) determine whether the richness and phylogenetic diversity of plants within restoration plots influence the total biomass and the taxonomic, functional, and phylogenetic diversity of dung beetles; and (b) determine if the establishment of restoration plots allows to recover the abundance and diversity of dung beetle communities, relative to what is found in livestock pastures. In the restoration plots, the abundance of Scarabaeinae beetles and the total biomass, functional originality, and phylogenetic diversity of dung beetles were positively related to the number of plant species, but only the abundance of Scarabaeinae and total biomass of all dung beetles were positively related to the plant phylogenetic diversity. Finally, the restoration plots allowed a threefold increase in the total biomass of dung beetles relative to the biomass found in pastures. We discuss how restoration plots with high plant species richness and phylogenetic diversity can favor the recovery of dung beetle communities by potentially creating more niche opportunities.


Asunto(s)
Biodiversidad , Biomasa , Escarabajos , Filogenia , Animales , Plantas , Herbivoria , Bosques , Ecosistema
3.
PLoS One ; 20(2): e0316472, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39899503

RESUMEN

Africa is entering a new fire paradigm, with climate change and increasing anthropogenic pressure shifting the patterns of frequency and severity. Thus, it is crucial to use available information and technologies to understand vegetation dynamics during the post-fire recovery processes. The main objective of this study was to evaluate the seasonal spatio-temporal trends of vegetation recovery in response to fires across Africa, from 2001 to 2020. Non-parametric tests were used to analyze MODIS Normalized Difference Vegetation Index (NDVI) products comparing the following three-month seasonal periods: December-February (DJF), March-May (MAM), June-August (JJA), and September-November (SON). We evaluated the seasonal spatial trends of NDVI in burned areas by hemisphere, territory, or country, and by land cover types, and fire recurrences, with a focus on forested areas. The relationships between the seasonal spatial trend and three climatic variables (i.e. maximum air temperature, precipitation, and vapor pressure deficit) were then analyzed. For the 8.7 million km2 burned in Africa over the past 22 years, we observed several seasonal spatial trends of NDVI. The highest proportions of areas with increasing trend (p < 0.05) was recorded in MAM for both hemispheres, with 22.0% in the Northern Hemisphere and 17.4% in the Southern Hemisphere. In contrast, areas with decreasing trends (p < 0.05), showed 4.8-5.5% of burned area in the Northern Hemisphere, peaking in JJA, while the Southern Hemisphere showed a range of 7.1 to 10.9% with the highest proportion also in JJA. Regarding land cover types, 48.0% of fires occurred in forests, 24.1% in shrublands, 16.6% in agricultural fields, and 8.9% in grasslands/savannas. Consistent with the overall trend, the area exhibiting an increasing trend in NDVI values (p < 0.05) within forested regions had the highest proportion in MAM, with 19.9% in the Northern Hemisphere and 20.6% in the Southern Hemisphere. Conversely, the largest decreasing trend (p < 0.05) was observed in DJF in the Northern Hemisphere (2.7-2.9%) and in JJA in the Southern Hemisphere (7.2-10.4%). Seasonally, we found a high variability of regeneration trends of forested areas based on fire recurrences. In addition, we found that of the three climatic variables, increasing vapor pressure deficit values were more related to decreasing NDVI levels. These results indicate a strong component of seasonality with respect to fires, trends of vegetation increase or decrease in the different vegetation covers of the African continent, and they contribute to the understanding of climatic conditions that contribute to vegetation recovery. This information is helpful for researchers and decision makers to act on specific sites during restoration processes.


Asunto(s)
Cambio Climático , Estaciones del Año , África , Incendios , Análisis Espacio-Temporal , Bosques , Ecosistema
4.
Mol Biol Rep ; 52(1): 196, 2025 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-39903394

RESUMEN

Bees play a critical role as pollinators in ecosystem services, contributing significantly to the sexual reproduction and diversity of plants. The Caatinga biome in Brazil, home to around 200 bee species, provides an ideal habitat for these species due to its unique climate conditions. However, this biome faces threats from anthropogenic processes, making it urgent to characterise the local bee populations efficiently. Traditional taxonomic surveys for bee identification are complex due to the lack of suitable keys and expertise required. As a result, molecular barcoding has emerged as a valuable tool, using genome regions to compare and identify bee species. However, little is known about Caatinga bees to develop these molecular tools further. This study addresses this gap, providing an updated list of 262 Caatinga bee species across 86 genera and identifying ~ 40 primer sets to aid in barcoding these species. The findings highlight the ongoing work needed to fully characterise the Caatinga biome's bee distribution and species or subspecies to support more effective monitoring and conservation efforts.


Asunto(s)
Código de Barras del ADN Taxonómico , Ecosistema , Abejas/genética , Abejas/clasificación , Animales , Código de Barras del ADN Taxonómico/métodos , Brasil , Polinización/genética , Filogenia , Biodiversidad
5.
Environ Monit Assess ; 197(2): 181, 2025 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-39847166

RESUMEN

Freshwater ecosystems under the influence of human activities are subject to multiple environmental stressors that lead to biodiversity loss and habitat modification. In recent years, various organisms have been used as bioindicators to detect environmental changes by their ability to perceive changes in community attributes. A good example is the semiaquatic bugs (Hemiptera, infra order Gerromorpha) that act as predators and are sensitive to subtle changes in environmental conditions. Our research aimed to investigate the responses of Gerromorpha communities, genera, and species along an environmental gradient in 45 Amazon streams. The environmental gradient was assessed utilizing the Habitat Integrity Index (HII) across the sampled streams, yielding a collection of 2.212 specimens representing three families, seven genera, and 36 species. The habitat integrity, represented by the HII, showed a positive relationship between species richness and the richness of genera of Gerromorpha, underscoring that both species and genera respond to environmental change in the analyzed habitats. Brachymetra lata (Gerridae), Rhagovelia jubata, and R. elegans (Veliidae) were the most sensitive taxa with a positive relationship to HII. Streams characterized by higher anthropogenic disturbance and reduced riparian vegetation were associated with a biodiversity pattern marked by increased abundance and frequency of generalist species and reduced genus frequency within the Veliidae family. We hope that the results of this study will contribute to future biomonitoring programs in response to habitat and species loss, aiming to assist decision-making to protect and restore riparian vegetation areas.


Asunto(s)
Biodiversidad , Ecosistema , Monitoreo del Ambiente , Heterópteros , Ríos , Animales , Monitoreo del Ambiente/métodos , Ríos/química , Brasil
6.
Neotrop Entomol ; 54(1): 24, 2025 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-39821717

RESUMEN

The diverse ecosystems of the Amazon biome play a vital role in the maintenance of biodiversity and delivering essential ecosystem services at both local and global levels. Small-bodied generalist insects, such as those from the order Odonata, contribute significantly to these services and are recognized as sensitive bioindicators of environmental quality. The present study evaluated the diversity and distribution of adult odonates in the Legal Amazonia zone of the Brazilian state of Maranhão, to identify the key environmental drivers shaping local odonate communities. We sampled 27 streams along a landscape gradient ranging from degraded to preserved conditions within the Pindaré River basin. Our findings reveal that environmental integrity positively influences the odonate diversity and abundance, with degraded environment favoring generalist species. These generalist species are particularly vulnerable to habitat loss, particularly the reduction of dense vegetation. Notably, the discovery of Erythrodiplax unimaculata in Maranhão highlights the importance of the study in a region with limited research on the group. The study underscores the urgent need for continuous biodiversity monitoring and conservation strategies to mitigate the impacts of widespread environmental disturbances in the region.


Asunto(s)
Biodiversidad , Ecosistema , Odonata , Brasil , Animales , Odonata/clasificación , Ríos , Conservación de los Recursos Naturales
7.
PLoS One ; 20(1): e0317571, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39841713

RESUMEN

Ice-free areas are habitats for most of Antarctica's terrestrial biodiversity. Although fungal communities are an important element of these habitats, knowledge of their assemblages and ecological functions is still limited. Herein, we investigated the diversity, composition, and ecological functionality of fungal communities inhabiting sediments from ice-free areas across pristine and anthropogenically impacted sites in the Fildes Peninsula on King George Island, Antarctica. Samples were collected from both pristine and disturbed areas. We used the internal transcribed spacer (ITS1) region via Illumina sequencing of 34 sediment samples for fungal identification. The Ascomycota (14.6%) and Chytridiomycota (11.8%) were the most dominant phyla, followed by Basidiomycota (8.1%), Rozellomycota (7.0%), Mucoromycota (4.0%), while 34.9% of the fungal diversity remained unidentified. From a total of 1073 OTUs, 532 OTUs corresponded to 114 fungal taxa at the genus level, and 541 OTUs remained unassigned taxonomically. The highest diversity, with 18 genera, was detected at site A-3. At the genus level, there was no preference for either pristine or disturbed sites. The most widely distributed genera were Betamyces (Chytridiomycota), occurring in 29 of the 34 sites, and Thelebolus (Ascomycota), detected in 8 pristine sites and 7 disturbed sites. The Glomeraceae gen. incertae sedis was more common in disturbed sites. A total of 23 different ecological guilds were recorded, with the most abundant guilds being undefined saprotrophs, plant pathogens, plant saprotrophs, pollen saprotrophs, and endophytes. The fungal communities did not show significant differences between pristine and disturbed sites, suggesting that the anthropogenic impact is either not too intense or prolonged, that the spatial distance between the sampled sites is small, and/or that the environmental factors are similar. Although our study revealed a high fungal diversity with various ecological specializations within these communities, nearly one-third of the diversity could not be assigned to any specific taxonomic category. These findings highlight the need for further taxonomic research on fungal species inhabiting ice-free areas. Without identifying the species present, it is difficult to assess potential biodiversity loss due to environmental changes and/or human activities.


Asunto(s)
Biodiversidad , Hongos , Regiones Antárticas , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Islas , Ecosistema , Filogenia , Sedimentos Geológicos/microbiología , Micobioma/genética
8.
Environ Monit Assess ; 197(2): 142, 2025 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-39776261

RESUMEN

Landscape metrics (LM) play a crucial role in fields such as urban planning, ecology, and environmental research, providing insights into the ecological and functional dynamics of ecosystems. However, in dynamic systems, generating thematic maps for LM analysis poses challenges due to the substantial data volume required and issues such as cloud cover interruptions. The aim of this study was to compare the accuracy of land cover maps produced by three temporal aggregation methods: median reflectance, maximum normalised difference vegetation index (NDVI), and a two-date image stack using Sentinel-2 (S2) and then to analyse their implications for LM calculation. The Google Earth Engine platform facilitated data filtering, image selection, and aggregation. A random forest algorithm was employed to classify five land cover classes across ten sites, with classification accuracy assessed using global measurements and the Kappa index. LM were then quantified. The analysis revealed that S2 data provided a high-quality, cloud-free dataset suitable for analysis, ensuring a minimum of 25 cloud-free pixels over the study period. The two-date and median methods exhibited superior land cover classification accuracy compared to the max NDVI method. In particular, the two-date method resulted in lower fragmentation-heterogeneity and complexity metrics in the resulting maps compared to the median and max NDVI methods. Nevertheless, the median method holds promise for integration into operational land cover mapping programmes, particularly for larger study areas exceeding the width of S2 swath coverage. We find patch density combined with conditional entropy to be particularly useful metrics for assessing fragmentation and configuration complexity.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Estaciones del Año , Monitoreo del Ambiente/métodos , Imágenes Satelitales , Sistemas de Información Geográfica
9.
J Morphol ; 286(1): e70025, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39828958

RESUMEN

A major goal of evolutionary ecology is to understand the interaction between ecological differences and the functional morphology of organisms. Studies of this type are common among flying birds but less so in penguins. Penguins (Spheniscidae) are the most derived extant underwater flying birds using their wings for swimming and beak when foraging. The Humboldt Penguin (Spheniscus humboldti) and Magellanic Penguin (S. magellanicus) occur along the coast of South America and their morphology was compared in allopatry and sympatry throughout their ranges. Measurements included: mass, tarsus length, four beak/head dimensions, bite force, wing loading, and aspect ratio. A thin-plate spline/relative warp analysis was also used to detect subtle differences in wing shape. Both species generally overlapped in trait morphology, but Magellanic Penguins showed greater trait diversity. Wing morphology was more homogenous between species than beak morphology indicating a similar mode of locomotion but potential differences in prey procurement. Morphological character displacement in sympatry was only evident in beak length. Local adaptation was common in other traits, and Punta Norte (Argentina) was often distinct in having high variation, notably in beak depth, wing loading, and wing shape (relative warp 1). This may be attributed to the fact that penguins here dive deep and forage farther from their colony; they also have a greater colony size that may contribute to greater intraspecific competition for resources. These results support a potentially optimal wing design for aquatic movement, which likely applies to other penguin species. Differences in morphology may also be related to differences between Atlantic and Pacific ecosystems.


Asunto(s)
Pico , Spheniscidae , Alas de Animales , Animales , Spheniscidae/anatomía & histología , Spheniscidae/fisiología , América del Sur , Alas de Animales/anatomía & histología , Pico/anatomía & histología , Ecosistema , Evolución Biológica
10.
PeerJ ; 13: e18412, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39802187

RESUMEN

Acoustic communities are acoustically active species aggregations within a habitat, where vocal interactions between species can interfere their communication. The acoustic adaptation hypothesis (AAH) explains how the habitat favors the transmission of acoustic signals. To understand how bird acoustic communities are structured, we tested the effect of habitat structure on the phylogenetic structure, and on the phylogenetic and vocal diversity of acoustic communities in a semi-arid zone of Mexico. From autonomous recordings in three types of vegetation (crop fields, tetecheras, and mesquiteras), which differ in terms of complexity and canopy openness, we evaluated sound attenuation, and estimated metrics of phylogenetic structure and diversity as well as acoustic diversity with the use of two indices. Mesquiteras showed greater vegetation density, more attenuation, more vocal diversity, as well as a phylogenetic structure that tended towards overdispersion, in contrast to crop fields that showed less vegetation density, less attenuation, less vocal diversity and more phylogenetic relatedness, while tetecheras showed intermediate patterns. Phylogenetic structure was explained by vegetation density and excess attenuation. The higher vocal diversity, phylogenetic structure tended towards overdispersion. These results suggest a role for environmental filters in the crop fields, where more closely related species with similar vocal characteristics coexist (supporting AAH), and probably competitive exclusion in the mesquiteras, where more distantly related species coexist, promoting vocal diversity. This study offers information about the influence of habitat on the acoustic community structure, which could inform our understanding of the distribution of species from acoustic perspective.


Asunto(s)
Aves , Ecosistema , Filogenia , Vocalización Animal , México , Animales , Aves/fisiología , Vocalización Animal/fisiología , Acústica , Biodiversidad
11.
Sensors (Basel) ; 25(2)2025 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-39860677

RESUMEN

Developing the capacity to monitor species diversity worldwide is of great importance in halting biodiversity loss. To this end, remote sensing plays a unique role. In this study, we evaluate the potential of Global Ecosystem Dynamics Investigation (GEDI) data, combined with conventional satellite optical imagery and climate reanalysis data, to predict in situ alpha diversity (Species richness, Simpson index, and Shannon index) among tree species. Data from Sentinel-2 optical imagery, ERA-5 climate data, SRTM-DEM imagery, and simulated GEDI data were selected for the characterization of diversity in four study areas. The integration of ancillary data can improve biodiversity metrics predictions. Random Forest (RF) regression models were suitable for estimating tree species diversity indices from remote sensing variables. From these models, we generated diversity index maps for the entire Cerrado using all GEDI data available in orbit. For all models, the structural metric Foliage Height Diversity (FHD) was selected; the Renormalized Difference Vegetation Index (RDVI) was also selected in all species diversity models. For the Shannon model, two GEDI variables were selected. Overall, the models indicated performances for species diversity ranging from (R2 = 0.24 to 0.56). In terms of RMSE%, the Shannon model had the lowest value among the diversity indices (31.98%). Our results suggested that the developed models are valuable tools for assessing species diversity in tropical savanna ecosystems, although each model can be chosen based on the objectives of a given study, the target amount of performance/error, and the availability of data.


Asunto(s)
Biodiversidad , Árboles , Clima Tropical , Árboles/clasificación , Tecnología de Sensores Remotos/métodos , Pradera , Ecosistema , Imágenes Satelitales , Madera
12.
Vet Parasitol Reg Stud Reports ; 57: 101175, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39855863

RESUMEN

Parasites significantly influence ecosystems by controlling host populations and spreading diseases, thereby impacting ecological balances. In the Neotropics, hematophagous bat flies and mites are common ectoparasites of bats. The state of Mato Grosso, Brazil, hosts a diverse bat fauna across its Amazon Forest, Cerrado, and Pantanal habitats. We described bat flies and wing mites associated with bats in an urban area in the Amazon-Cerrado transition. Despite the expected diversity of bat in the study area, we expect to find a low number of ectoparasites species, as urban areas are typically associated with reduced parasite diversity. Bats were captured using mist nets, and ectoparasites collected manually or with tweezers and identified under the stereomicroscope. We found 10 species of ectoparasites (seven bat flies and three wingmites) from 181 bats across 22 species. The study found low ectoparasite diversity, possibly due to the small number of bats captured or the constraints found in the urban environment. Most observed bat-ectoparasite associations were consistent with previous studies, but some unexpected associations suggested possible contamination or transient relationships. This research fills a gap in the knowledge of bat ectoparasites in Mato Grosso, contributing to understanding bat-ectoparasite dynamics in diverse habitats.


Asunto(s)
Quirópteros , Dípteros , Infestaciones Ectoparasitarias , Animales , Quirópteros/parasitología , Brasil/epidemiología , Dípteros/clasificación , Infestaciones Ectoparasitarias/veterinaria , Infestaciones Ectoparasitarias/parasitología , Infestaciones Ectoparasitarias/epidemiología , Ácaros/clasificación , Ácaros/fisiología , Infestaciones por Ácaros/veterinaria , Infestaciones por Ácaros/parasitología , Infestaciones por Ácaros/epidemiología , Ecosistema , Ciudades , Biodiversidad , Masculino , Femenino
13.
PLoS One ; 20(1): e0317356, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39854366

RESUMEN

Knowledge of the potential distribution and locations of poorly known threatened species is crucial for guiding conservation strategies and new field surveys. The painted tree-rat (Callistomys pictus) is a monospecific, rare, and endangered echimyid rodent endemic to the southern Bahia Atlantic Forest in Brazil. There have been no records of the species published in the last 20 years, and the region has experienced significant forest loss and degradation. According to the IUCN, only 13 specimens had been previously reported, with 12 found in the north of Ilhéus and adjacent municipalities, and one recorded approximately 200 km away from this region, suggesting that its distribution might be wider. We aimed to search for unpublished and more recent records of the C. pictus, by consulting the gray literature (including Environmental Impact Study (EIA) reports, Brazilian Red Lists, and management plans of protected areas), scientific collections, online databases, and mastozoologists working in the region. We estimated the species' potential distribution using Ecological Niche Modeling to identify regions, municipalities, and protected areas most likely to support this species, based on factors such as climate suitability and forest cover. We reported three new sightings of the species, including the first within a protected area. We estimated suitable climate conditions across 23,151 km2, of which 9,225 km2 has a high potential for harboring the species. The area between Itacaré and Valença needs more extensive survey efforts as it has high habitat suitability and only one record has been confirmed there so far. Meanwhile, the region between Una and Ilhéus urgently requires habitat conservation initiatives. While the species may have a broader distribution than previously thought, its known occurrences are limited to a few locations, and suitable habitats are underrepresented in protected areas. Additionally, the rarity of sightings continues to indicate a concerning conservation status.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Especies en Peligro de Extinción , Animales , Brasil , Especies en Peligro de Extinción/tendencias , Bosques , Murinae/fisiología
14.
PLoS One ; 20(1): e0315904, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39854398

RESUMEN

Bauxite mining has been caused severe changes in the natural ecosystems of the Amazon, but the restoration of these areas is mandatory by federal law in Brazil. The recolonization of fauna is crucial to establishing the ecological functions of recovering forests, and the small nonflying mammals can stand out in this process. Assessing taxonomic and functional diversity parameters, we demonstrated that in the early stages of forest recovery post-bauxite mining, between 6 and 11 years, it is possible to restore approximately 45% of the richness of small non-flying mammal species from the original habitats, that in this case were altered Primary Forests. However, the species richness parameter alone does not reflect the recovery of taxonomic or functional diversity at this stage of forest succession. Although 34.8% of the species composition is shared between the Altered Primary Forest and Forest Areas in Restoration, the abundance distribution per species is less balanced in the latter habitat. The areas did not exhibit significant difference between the functional divergence and functional evenness of ecological functions performed by small nonflying mammals; however, they present differences in terms of the functional richness. We also observed that some functional traits of species, such as larger body mass, are more closely related to the structural characteristics of the Primary Forest, such as high basal area values, litter and percentage forest cover. In the forest recovery areas, we observed a predominance of terrestrial species and those with granivorous and insectivorous diets. Furthermore, our results highlight the importance of applying different taxonomic and functional diversity parameters to understand better the fauna recovery patterns in degraded areas undergoing restoration.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Bosques , Mamíferos , Minería , Animales , Brasil , Conservación de los Recursos Naturales/métodos , Ecosistema
15.
Sci Total Environ ; 962: 178426, 2025 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-39813835

RESUMEN

Environmental characteristics drastically shape the host-parasite associations under natural conditions. This is the case of parasites such as avian haemosporidians which naturally infect birds and are transmitted by insect vectors. Landscape characteristics are known to determine the epidemiology of transmission of these parasites in the wild, but the strength of these factors may differ at different spatial scales. We studied the effects of the landscape structure and environmental variables on the prevalence and richness of lineages of avian haemosporidian parasites (genera Plasmodium, Haemoproteus and Leucocytozoon) infecting birds in a highly diverse area of Antioquia, Colombia. We screened blood samples from 678 individuals across 90 bird species for number of infections, prevalence and richness of haemosporidian lineages in sites surrounding three hydroelectric dams. We obtained environmental and landscape structure variables around the bird sampling points at different spatial scales (from 50 to 500 m radii, every 50 m) and selected the most important ones. We modelled the relationships between parasite infection variables and landscape structural and environmental characteristics. Effects of landscape structure on variables reflecting haemosporidian infections varied according to the selected scale of analyses. The scale of the effect of landscape structure was larger for the number of infections and prevalence (Average = 350 and 425 m radius) than for lineage richness (Average = Plasmodium 219 m, Haemoproteus 244 m). Agricultural patch density notably increased number of infection rates (pseudo-R2 = 0.68). The number of infections and the richness of Haemoproteus lineages correlated with agricultural connectivity at larger scales (500 m). Haemosporidian prevalence was primarily linked with proportion forest and agricultural covers. Haemoproteus richness was influenced by connectivity and NDVI - Normalized Difference Vegetation Index (pseudo-R2 = 0.83), while Plasmodium richness was affected by anthropogenic density, edge density, forest proportion, and temperature (pseudo-R2 = 0.79). Changes in parasite infection and prevalence remain difficult to predict, as each parasite-host system is susceptible to many unaccounted variables. This study found that transformed landscapes, particularly density of anthropogenic and agricultural patches nearby increases haemosporidian parasites at different scales. These findings underscore the complex interplay between landscape structure and haemosporidian infections in avian hosts in tropical ecosystems.


Asunto(s)
Enfermedades de las Aves , Aves , Haemosporida , Animales , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/parasitología , Colombia/epidemiología , Interacciones Huésped-Parásitos , Ecosistema , Infecciones Protozoarias en Animales/epidemiología , Prevalencia
16.
J Environ Manage ; 374: 124102, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39799773

RESUMEN

The Eastern Boundary Upwelling Systems (EBUS) sustains some of the most productive marine systems on Earth. Within each of these systems, the upwelling process exhibits spatial and temporal variation resulting in marked differences in upwelling intensity and seasonality along extensive coastlines. The study of this variation is well needed, given the magnitude of the services provided by upwelling, and the impending impacts of global warming on EBUS. The critical link between the physical variability associated with upwelling intensity and its consequences on socio-ecological variables remain severely understudied. This study aimed to address such a gap by exploring the influence of coastal upwelling intensity on socio-ecological attributes of co-management units named Marine Exploitation Areas for Benthic Resources (MEABRs), along one the most productive ecosystems of the world: The southern Humboldt Current system. We evaluated the non-linear influence of upwelling on 1) the harvest of economically important resources, 2) the number of exploited species, 3) number and gender distribution of fishers involved, and 4) fishery activities. Our data indicated that on the one hand the annual harvest of commercial species, and all the exploited resources combined, were consistently higher in MEABRs associated with intermediate to high upwelling intensities. On the other hand, the harvest of kelp, the number of species harvested, and the number of fishers per MEABR increased towards low upwelling intensities, showing signals of fishery diversification. Interestingly, representation of female fishers increased towards high upwelling intensities, suggesting that multiple factors account for the variation in this, and other socio-ecological variables examined. Our study provides first-hand information about harvest levels and the allocation of fishery activities and gender distribution when MEABRs associated with different upwelling intensities are compared. Such information will assist in the identification of ecological and social vulnerabilities in a global warming scenario.


Asunto(s)
Ecosistema , Explotaciones Pesqueras , Conservación de los Recursos Naturales , Animales , Calentamiento Global
17.
J Environ Manage ; 374: 124066, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39805159

RESUMEN

Fires are increasingly affecting tropical biomes, where landscape-fire interactions remain understudied. We investigate the fire-proneness-the likelihood of a land use or land cover (LULC) type burning more or less than expected based on availability-in the Brazilian Atlantic Forest (AF). This biodiversity hotspot is increasingly affected by fires due to human activities and climate change. Using a selection ratio-based approach, we analyzed fire-LULC interactions in 40,869 fires over a 35-year period (1987-2022) across various ecoregions in the AF. Our findings revealed that secondary forests, forest areas that have regrown after major disturbances, burned 61% more than expected by chance, whereas old-growth forests, native forests that have developed over very long periods, burned 57% less than expected, highlighting a nearly inverse relationship in their fire-proneness. Interestingly, our data indicate that pastures in the AF are less prone to fire than expected, despite being considered among the land uses that burn the most in Brazil. Other LULCs showed variable fire-proneness, with some differences between ecoregions. Over time, the fire-proneness of secondary forests decreased, likely due to forest aging and changes in land management practices. We emphasize the necessity for tailored fire management strategies that address the unique vulnerabilities of secondary forests, particularly in the context of ongoing restoration efforts aimed at increasing native forests. Effective measures, including the implementation of 'fire-smart management' practices and enhancing the perceived value of secondary forests among local communities, are crucial for mitigating fire risks. Integrating these strategies with incentive-based approaches can bolster fire prevention, ensuring the long-term success of restoration programs. Our study provides a framework for understanding fire-landscape dynamics in tropical forests and offers actionable insights for practitioners working to safeguard these biomes from the escalating threat of wildfires.


Asunto(s)
Incendios , Bosques , Brasil , Cambio Climático , Conservación de los Recursos Naturales , Biodiversidad , Ecosistema
18.
Sci Adv ; 11(3): eadn4004, 2025 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-39813344

RESUMEN

Coral reefs can mitigate flood damages by providing protection to tropical coastal communities whose populations are dense, growing fast, and have predominantly lower-middle income. This study provides the first fine-scale, regionally modeled valuations of how flood risk reductions associated with hybrid coral reef restoration could benefit people, property, and economic activity along Florida and Puerto Rico's 1005 kilometers of reef-lined coasts. Restoration of up to 20% of the regions' coral reefs could provide flood reduction benefits greater than costs. Reef habitats with the greatest benefits are shallow, nearshore, and fronting low-lying, vulnerable communities, which are often where reef impacts and loss are the greatest. Minorities, children, the elderly, and those below the poverty line could receive more than double the hazard risk reduction benefits of the overall population, demonstrating that reef restoration as a nature-based solution can have positive returns on investment economically and socially by providing protection to the most vulnerable people.


Asunto(s)
Conservación de los Recursos Naturales , Arrecifes de Coral , Análisis Costo-Beneficio , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Florida , Puerto Rico , Humanos , Inundaciones/economía , Ecosistema , Restauración y Remediación Ambiental/economía , Restauración y Remediación Ambiental/métodos , Poblaciones Vulnerables
19.
Sci Rep ; 15(1): 2073, 2025 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-39814950

RESUMEN

During the mating season, reproductive individuals of numerous insect species gather in rendezvous areas, which increases mating opportunities. Male hymenopterans often have to move considerable distances during a particular season, searching or waiting for receptive females. Such behavior is likely driven by a complex combination of individual and species-specific traits, environmental influence, and landscape cues. Our field study aimed to determine factors affecting the occurrence of Vespula spp. drones, focusing on the influence of vegetation traits, atmospheric factors and diel effects, and the species occurrence proportion in an invaded area in Patagonia. Our results indicate that the probability of drone presence over different types of vegetation is affected both by plant species and height. Also, weather and time of day influence the number of individuals simultaneously gathering, as higher abundances of flying drones are found in early hours, warmer days and at low cloud cover. Lastly, through mid-flight drone captures, we determined that both V. germanica and V. vulgaris drones are found concurrently in the same rendezvous areas. This constitutes the first exploratory field study reporting the heterospecific occurrence of Vespula spp. drones and overall, our results contribute to the understanding of yellowjackets mating systems.


Asunto(s)
Conducta Sexual Animal , Animales , Masculino , Conducta Sexual Animal/fisiología , Especies Introducidas , Femenino , Ecosistema , Estaciones del Año , Ambiente
20.
Am J Bot ; 112(1): e16455, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39799390

RESUMEN

PREMISE: The movement of lineages into novel areas can promote ecological opportunity and adaptive radiation, leading to significant species diversity. Not all studies, however, have identified support for ecological opportunity associated with novel intercontinental colonizations. To gain key insights into the drivers of ecological opportunity, we tested whether intercontinental dispersals resulted in ecological opportunity using the Hydrangeaceae-Loasaceae clade, which has numerous centers of diversity across the globe. METHODS: A time-calibrated phylogeny was reconstructed from four molecular markers. We tested for bursts of speciation rates followed by a decrease as expected phylogenetic patterns under an ecological opportunity model. Ancestral ranges were estimated using historical biogeographic analyses to examine the relationships of ancestral distributions and habitats with speciation and extinction rates. RESULTS: Hydrangeaceae and Loasaceae originated in arid Mesoamerica, then dispersed into South America, Eurasia, and eastern North America. Six clades experienced increased diversification rates, but those increases were not associated with transitions into new continental areas. Mentzelia section Bartonia was the only clade that exhibited a burst of speciation followed by a decrease. Both families originated in arid environments and experienced multiple transitions into mesic and tropical environments, but Loasaceae experienced a higher speciation-to-extinction ratio than Hydrangeaceae in the western Nearctic. CONCLUSIONS: Dispersal between continents did not trigger speciation rate shifts in Loasaceae and Hydrangeaceae. Instead, shifts occurred in regions inhabited by intrafamilial relatives and were likely driven by climate change in the Miocene, where species in drier microhabitats diversified into newly created habitats.


Asunto(s)
Filogenia , Evolución Biológica , Especiación Genética , Filogeografía , Dispersión de las Plantas , América Central , Biodiversidad , Ecosistema , América del Sur
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